Table of Contents i

TABLE OF CONTENTS

Introduction ..........................................................................................................................1

Background..................................................................................................................... 2

Addressing Data Needs ................................................................................................... 3

Public Health Uses.......................................................................................................... 3

Data Presented for Biochemical Indicators...................................................................... 4

Interpreting the Data ...................................................................................................... 5

Sources of Information on Nutrition Monitoring to Help Interpret the Data.................. 6

The National Health and Nutrition Examination Survey (NHANES)............................. 7

Data Analysis.................................................................................................................. 7

References..................................................................................................................... 10

1 Water-Soluble Vitamins ....................................................................................................13

B Vitamins and Related Biochemical Compounds ........................................................... 14

Background Information............................................................................................... 14

Highlights..................................................................................................................... 18

Figure H.1.a Age-adjusted geometric mean concentrations of serum folate 

in the U.S. population aged 4 years and older by gender 

or race/ethnicity, NHANES 1988–2006 .............................................................19

Figure H.1.b Age-adjusted geometric mean concentrations of RBC folate 

in the U.S. population aged 4 years and older by gender

or race/ethnicity, NHANES 1988–2006 .............................................................19

Figure H.1.c Age-adjusted geometric mean concentrations of serum 

vitamin B12 in the U.S. population aged 4 years and older 

by gender or race/ethnicity, NHANES 1991–2006 .............................................20

Figure H.1.d Prevalence estimates of low serum vitamin B12, 

high plasma methylmalonic acid, and high plasma total 

homocysteine concentrations in U.S. persons 60 years and older, 

NHANES 2003–2006 ........................................................................................20

Detailed Observations................................................................................................... 20

Table 1.1.a.1 Serum folate: Concentrations ..............................................................................22

Figure 1.1.a Serum folate: Concentrations by age group .........................................................23

Tables 1.1.a.2–5 Serum folate: Concentrations by race/ethnic group .............................................24

Table 1.1.b Serum folate: Concentrations by survey cycle .....................................................26

Figure 1.1.b Serum folate: Concentrations by survey cycle .....................................................27

Table 1.2.a.1 Red blood cell folate: Concentrations..................................................................28

Figure 1.2.a Red blood cell folate: Concentrations by age group .............................................29

Tables 1.2.a.2–5 Red blood cell folate: Concentrations by race/ethnic group .................................30

Table 1.2.b Red blood cell folate: Concentrations by survey cycle .........................................32

Figure 1.2.b Red blood cell folate: Concentrations by survey cycle .........................................33

Table 1.2.c Red blood cell folate: Prevalence (< 95 ng/mL)....................................................34

Table 1.2.d Red blood cell folate: Prevalence by survey cycle (< 95 ng/mL) ...........................35

Table 1.3.a.1 Serum pyridoxal-5’-phosphate: Concentrations...................................................36

Figure 1.3.a Serum pyridoxal-5’-phosphate: Concentrations by age group ..............................37

Tables 1.3.a.2–5 Serum pyridoxal-5’-phosphate: Concentrations by race/ethnic group ..................38

Table 1.3.c Serum pyridoxal-5’-phosphate: Prevalence (< 20 nmol/L)....................................40

Table 1.4.a.1 Serum 4-pyridoxic acid: Concentrations..............................................................42

Figure 1.4.a. Serum 4-pyridoxic acid: Concentrations by age group.........................................43

Tables 1.4.a.2–5 Serum 4-pyridoxic acid: Concentrations by race/ethnic group.............................44
ii 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.5.a.1 Serum vitamin B12: Concentrations....................................................................46

Figure 1.5.a Serum vitamin B12: Concentrations by age group...............................................47

Tables 1.5.a.2–5 Serum vitamin B12: Concentrations by race/ethnic group...................................48

Table 1.5.b Serum vitamin B12: Concentrations by survey cycle ...........................................50

Figure 1.5.b Serum vitamin B12: Concentrations by survey cycle ...........................................51

Table 1.5.c Serum vitamin B12: Prevalence (< 200 pg/mL) ...................................................52

Table 1.5.d Serum vitamin B12: Prevalence by survey cycle (< 200 pg/mL) ...........................53

Table 1.6.a.1 Plasma total homocysteine: Concentrations.........................................................54

Figure 1.6.a Plasma total homocysteine: Concentrations by age group....................................55

Tables 1.6.a.2–5 Plasma total homocysteine: Concentrations by race/ethnic group........................56

Table 1.6.b Plasma total homocysteine: Concentrations by survey cycle ................................58

Figure 1.6.b Plasma total homocysteine: Concentrations by survey cycle ................................59

Table 1.6.c Plasma total homocysteine: Prevalence (> 13 μmol/L) .........................................60

Table 1.6.d Plasma total homocysteine: Prevalence by survey cycle (> 13 μmol/L) .................61

Table 1.7.a.1 Plasma methylmalonic acid: Concentrations........................................................62

Figure 1.7.a Plasma methylmalonic acid: Concentrations by age group...................................63

Tables 1.7.a.2–5 Plasma methylmalonic acid: Concentrations by race/ethnic group.......................64

Table 1.7.b Plasma methylmalonic acid: Concentrations by survey cycle................................66

Figure 1.7.b Plasma methylmalonic acid: Concentrations by survey cycle................................67

Table 1.7.c Plasma methylmalonic acid: Prevalence (> 271 nmol/L)......................................68

Table 1.7.d Plasma methylmalonic acid: Prevalence by survey cycle (> 271 nmol/L)..............69

References..................................................................................................................... 70

Vitamin C........................................................................................................................ 72

Background Information .............................................................................................. 72

Highlights..................................................................................................................... 74

Figure H.1.e Age-adjusted prevalence estimates of vitamin C deficiency 

in the U.S. population aged 6 years and older by race/ethnicity 

or gender, NHANES 2003–2006........................................................................74

Figure H.1.f Prevalence estimates of vitamin C deficiency and of low vitamin C 

concentrations in the U.S. population aged 6 years and older 

by age group, NHANES 2003–2006...................................................................74

Detailed Observations................................................................................................... 75

Table 1.8.a.1 Serum vitamin C: Concentrations.......................................................................76

Figure 1.8.a Serum vitamin C: Concentrations by age group ..................................................77

Tables 1.8.a.2–5 Serum vitamin C: Concentrations by race/ethnic group ......................................78

Table 1.8.b Serum vitamin C: Concentrations by survey cycle...............................................80

Figure 1.8.b Serum vitamin C: Concentrations by survey cycle ..............................................81

Table 1.8.c Serum vitamin C: Prevalence (< 11.4 μmol/L).....................................................82

Table 1.8.d Serum vitamin C: Prevalence by survey cycle (< 11.4 μmol/L).............................83

References..................................................................................................................... 84

2 Fat-Soluble Vitamins and Nutrients..................................................................................87

Vitamins A and E and Carotenoids.................................................................................. 88

Background Information............................................................................................... 88

Highlights..................................................................................................................... 91

Figure H.2.a Age-adjusted geometric mean concentrations of serum vitamin E 

in the U.S. population aged 6 years and older by gender or race/ethnicity, 

NHANES 1988–2006 ........................................................................................92

Detailed Observations................................................................................................... 92

Table 2.1.a.1 Serum vitamin A: Concentrations .......................................................................94

Figure 2.1.a Serum vitamin A: Concentrations by age group...................................................95

Tables 2.1.a.2–5 Serum vitamin A: Concentrations by race/ethnic group.......................................96

Table 2.1.b Serum vitamin A: Concentrations by survey cycle ...............................................98

Figure 2.1.b Serum vitamin A: Concentrations by survey cycle ...............................................99 

Table 2.1.c.1 Serum vitamin A: Prevalence (< 20 μg/dL) ........................................................100

Table 2.1.c.2 Serum vitamin A: Prevalence (> 100 μg/dL) ......................................................101

Table 2.1.d.1 Serum vitamin A: Prevalence by survey cycle (< 20 μg/dL) ................................102

Table 2.1.d.2 Serum vitamin A: Prevalence by survey cycle (> 100 μg/dL) ..............................103
Table of Contents iii

Table 2.2.a.1 Serum retinyl palmitate: Concentrations ...........................................................104

Figure 2.2.a Serum retinyl palmitate: Concentrations by age group.......................................105

Tables 2.2.a.2–5 Serum retinyl palmitate: Concentrations by race/ethnic group...........................106

Table 2.2.b Serum retinyl palmitate: Concentrations by survey cycle ...................................108

Figure 2.2.b Serum retinyl palmitate: Concentrations by survey cycle ..................................109

Table 2.3.a.1 Serum retinyl stearate: Concentrations ..............................................................110

Tables 2.3.a.2–5 Serum retinyl stearate: Concentrations by race/ethnic group..............................112

Table 2.3.b Serum retinyl stearate: Concentrations by survey cycle .....................................114

Figure 2.3.b Serum retinyl stearate: Concentrations by survey cycle .....................................115

Table 2.4.a.1 Serum vitamin E: Concentrations......................................................................116

Figure 2.4.a Serum vitamin E: Concentrations by age group.................................................117

Tables 2.4.a.2–5 Serum vitamin E: Concentrations by race/ethnic group.....................................118

Table 2.4.b Serum vitamin E: Concentrations by survey cycle .............................................120

Figure 2.4.b Serum vitamin E: Concentrations by survey cycle .............................................121

Table 2.4.c Serum vitamin E: Prevalence (< 500 μg/dL) ......................................................122

Table 2.4.d Serum vitamin E: Prevalence by survey cycle (< 500 μg/dL) ..............................123

Table 2.5.a.1 Serum gamma-tocopherol: Concentrations........................................................124

Figure 2.5.a Serum gamma-tocopherol: Concentrations by age group ...................................125

Tables 2.5.a.2–5 Serum gamma-tocopherol: Concentrations by race/ethnic group .......................126

Table 2.5.b Serum gamma-tocopherol: Concentrations by survey cycle ...............................128

Figure 2.5.b Serum gamma-tocopherol: Concentrations by survey cycle ...............................129

Table 2.6.a.1 Serum alpha-carotene: Concentrations ..............................................................130

Figure 2.6.a Serum alpha-carotene: Concentrations by age group..........................................131

Tables 2.6.a.2–5 Serum alpha-carotene: Concentrations by race/ethnic group .............................132

Table 2.6.b Serum alpha-carotene: Concentrations by survey cycle ......................................134

Figure 2.6.b Serum alpha-carotene: Concentrations by survey cycle ......................................135

Table 2.7.a.1 Serum trans-beta-carotene: Concentrations........................................................136

Figure 2.7.a Serum trans-beta-carotene: Concentrations by age group ...................................137

Tables 2.7.a.2–5 Serum trans-beta-carotene: Concentrations by race/ethnic group .......................138

Table 2.7.b Serum trans-beta-carotene: Concentrations by survey cycle ...............................140

Figure 2.7.b Serum trans-beta-carotene: Concentrations by survey cycle ...............................141

Table 2.8.a.1 Serum cis-beta-carotene: Concentrations............................................................142

Tables 2.8.a.2–5 Serum cis-beta-carotene: Concentrations by race/ethnic group...........................144

Table 2.8.b Serum cis-beta-carotene: Concentrations by survey cycle ...................................146

Figure 2.8.b Serum cis-beta-carotene: Concentrations by survey cycle ...................................147

Table 2.9.a.1 Serum beta-cryptoxanthin: Concentrations........................................................148

Figure 2.9.a Serum beta-cryptoxanthin: Concentrations by age group...................................149

Tables 2.9.a.2–5 Serum beta-cryptoxanthin: Concentrations by race/ethnic group.......................150

Table 2.9.b Serum beta-cryptoxanthin: Concentrations by survey cycle ...............................152

Figure 2.9.b Serum beta-cryptoxanthin: Concentrations by survey cycle ...............................153

Table 2.10.a.1 Serum lutein/zeaxanthin: Concentrations..........................................................154

Figure 2.10.a Serum lutein/zeaxanthin: Concentrations by age group .....................................155

Tables 2.10.a.2–5 Serum lutein/zeaxanthin: Concentrations by race/ethnic group .........................156

Table 2.10.b Serum lutein/zeaxanthin: Concentrations by survey cycle .................................158

Figure 2.10.b Serum lutein/zeaxanthin: Concentrations by survey cycle..................................159

Figure 2.11.a.1 Serum trans-lycopene: Concentrations...............................................................160

Figure 2.11.a Serum trans-lycopene: Concentrations by age group..........................................161

Tables 2.11.a.2–5 Serum trans-lycopene: Concentrations by race/ethnic group..............................162

Table 2.11.b Serum trans-lycopene: Concentrations by survey cycle.......................................164

Figure 2.11.b Serum trans-lycopene: Concentrations by survey cycle ......................................165

Table 2.12.a.1 Serum total lycopene: Concentrations ...............................................................166

Figure 2.12.a Serum total lycopene: Concentrations by age group ..........................................167

Tables 2.12.a.2–5 Serum total lycopene: Concentrations by race/ethnic group ..............................168

References................................................................................................................... 170
iv 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Vitamin D ..................................................................................................................... 172

Background Information............................................................................................. 172

Highlights................................................................................................................... 175

Figure H.2.b Age-adjusted geometric mean concentrations of serum 

25-hydroxyvitamin D in the U.S. population aged 12 years and 

older by gender or race/ethnicity, NHANES 1988–2006 ..................................175

Figure H.2.c Age-adjusted prevalence estimates of serum 25-hydroxyvitamin D 

concentrations < 30 and 30 to < 50 nmol/L in the U.S. population 

aged 1 year and older by race/ethnicity, NHANES 2003–2006 .........................176

Figure H.2.d Age- adjusted prevalence estimates of serum 25-hydroxyvitamin D 

concentrations < 40 nmol/L in the U.S. population aged 1 years 

and older by race/ethnicity, NHANES 2003–2006 ...........................................176

Detailed Observations................................................................................................. 177

Table 2.13.a.1 Serum 25-hydroxyvitamin D: Concentrations...................................................178

Figure 2.13.a Serum 25-hydroxyvitamin D: Concentrations by age group ..............................179

Tables 2.13.a.2–5 Serum 25-hydroxyvitamin D: Concentrations by race/ethnic group ..................180

Table 2.13.b Serum 25-hydroxyvitamin D: Concentrations by survey cycle ..........................182

Figure 2.13.b Serum 25-hydroxyvitamin D: Concentrations by survey cycle ..........................183

Table 2.13.c.1 Serum 25-hydroxyvitamin D: Prevalence (< 30 nmol/L)....................................184

Table 2.13.c.2 Serum 25-hydroxyvitamin D: Prevalence (30 to < 50 nmol/L) ..........................185

Table 2.13.c.3 Serum 25-hydroxyvitamin D: Prevalence (< 40 nmol/L)....................................186

Table 2.13.c.4 Serum 25-hydroxyvitamin D: Prevalence (> 125 nmol/L)..................................187

Table 2.13.d.1 Serum 25-hydroxyvitamin D: Prevalence by survey cycle (< 30 nmol/L) ...........188

Table 2.13.d.2 Serum 25-hydroxyvitamin D: Prevalence by survey cycle (30 to < 50 nmol/L) ..189

Table 2.13.d.3 Serum 25-hydroxyvitamin D: Prevalence by survey cycle (< 40 nmol/L) ...........190

Table 2.13.d.4 Serum 25-hydroxyvitamin D: Prevalence by survey cycle (> 125 nmol/L) .........191

References................................................................................................................... 192

Fatty Acids..................................................................................................................... 193

Background Information............................................................................................. 193

Highlights................................................................................................................... 196

Figure H.2.e Geometric mean concentrations of plasma fatty acids in the 

U.S. population from fasted adults 20 years and older, 

NHANES 2003–2004 ......................................................................................197

Figure H.2.f Geometric mean concentrations of plasma eicosapentaenoic 

acid in the U.S. population from fasted adults 20 years and 

older by race/ethnicity, NHANES 2003–2004 ..................................................198

Figure H.2.g Geometric mean concentrations of plasma docosahexaenoic 

acid in the U.S. population from fasted adults 20 years and 

older by race/ethnicity, NHANES 2003–2004 ..................................................198

Detailed Observations................................................................................................. 198

Table 2.14.a.1 Plasma myristic acid (14:0): Concentrations......................................................200

Figure 2.14.a Plasma myristic acid (14:0): Concentrations by age group.................................201

Tables 2.14.a.2–5 Plasma myristic acid (14:0): Concentrations by race/ethnic group.....................202

Table 2.15.a.1 Plasma palmitic acid (16:0): Concentrations......................................................204

Figure 2.15.a Plasma palmitic acid (16:0): Concentrations by age group.................................205

Tables 2.15.a.2–5 Plasma palmitic acid (16:0): Concentrations by race/ethnic group.....................206

Table 2.16.a.1 Plasma stearic acid (18:0): Concentrations.........................................................208

Figure 2.16.a Plasma stearic acid (18:0): Concentrations by age group....................................209

Tables 2.16.a.2–5 Plasma stearic acid (18:0): Concentrations by race/ethnic group........................210

Table 2.17.a.1 Plasma arachidic acid (20:0): Concentrations ....................................................212

Figure 2.17.a Plasma arachidic acid (20:0): Concentrations by age group ...............................213

Tables 2.17.a.2–5 Plasma arachidic acid (20:0): Concentrations by race/ethnic group ...................214

Table 2.18.a.1 Plasma docosanoic acid (22:0): Concentrations.................................................216

Figure 2.18.a Plasma docosanoic acid (22:0): Concentrations by age group ............................217

Tables 2.18.a.2–5 Plasma docosanoic acid (22:0): Concentrations by race/ethnic group ................218
Table of Contents v

Table 2.19.a.1 Plasma lignoceric acid (24:0): Concentrations ...................................................220

Figure 2.19.a Plasma lignoceric acid (24:0): Concentrations by age group ..............................221

Tables 2.19.a.2–5 Plasma lignoceric acid (24:0): Concentrations by race/ethnic group ..................222

Table 2.20.a.1 Plasma myristoleic acid (14:1n-5): Concentrations............................................224

Figure 2.20.a Plasma myristoleic acid (14:1n-5): Concentrations by age group .......................225

Tables 2.20.a.2–5 Plasma myristoleic acid (14:1n-5): Concentrations by race/ethnic group...........226

Table 2.21.a.1 Plasma palmitoleic acid (16:1n-7): Concentrations............................................228

Figure 2.21.a Plasma palmitoleic acid (16:1n-7): Concentrations by age group.......................229

Tables 2.21.a.2–5 Plasma palmitoleic acid (16:1n-7): Concentrations by race/ethnic group...........230

Table 2.22.a.1 Plasma cis-vaccenic acid (18:1n-7): Concentrations ...........................................232

Figure 2.22.a Plasma cis-vaccenic acid (18:1n-7): Concentrations by age group ......................233

Tables 2.22.a.2–5 Plasma cis-vaccenic acid (18:1n-7): Concentrations by race/ethnic group ..........234

Table 2.23.a.1 Plasma oleic acid (18:1n-9): Concentrations......................................................236

Figure 2.23.a Plasma oleic acid (18:1n-9): Concentrations by age group.................................237

Tables 2.23.a.2–5 Plasma oleic acid (18:1n-9): Concentrations by race/ethnic group.....................238

Table 2.24.a.1 Plasma eicosenoic acid (20:1n-9): Concentrations.............................................240

Figure 2.24.a Plasma eicosenoic acid (20:1n-9): Concentrations by age group ........................241

Tables 2.24.a.2–5 Plasma eicosenoic acid (20:1n-9): Concentrations by race/ethnic group ............242

Table 2.25.a.1 Plasma docosenoic acid (22:1n-9): Concentrations............................................244

Figure 2.25.a Plasma docosenoic acid (22:1n-9): Concentrations by age group.......................245

Tables 2.25.a.2–5 Plasma docosenoic acid (22:1n-9): Concentrations by race/ethnic group...........246

Table 2.26.a.1 Plasma nervonic acid (24:1n-9): Concentrations ...............................................248

Figure 2.26.a Plasma nervonic acid (24:1n-9): Concentrations by age group...........................249

Tables 2.26.a.2–5 Plasma nervonic acid (24:1n-9): Concentrations by race/ethnic group ..............250

Table 2.27.a.1 Plasma linoleic acid (18:2n-6): Concentrations..................................................252

Figure 2.27.a Plasma linoleic acid (18:2n-6): Concentrations by age group.............................253

Tables 2.27.a.2–5 Plasma linoleic acid (18:2n-6): Concentrations by race/ethnic group.................254

Table 2.28.a.1 Plasma alpha-linolenic acid (18:3n-3): Concentrations......................................256

Figure 2.28.a Plasma alpha-linolenic acid (18:3n-3): Concentrations by age group .................257

Tables 2.28.a.2–5 Plasma alpha-linolenic acid (18:3n-3): Concentrations by race/ethnic group .....258

Table 2.29.a.1 Plasma gamma-linolenic acid (18:3n-6): Concentrations ...................................260

Figure 2.29.a Plasma gamma-linolenic acid (18:3n-6): Concentrations by age group ..............261

Tables 2.29.a.2–5 Plasma gamma-linolenic acid (18:3n-6): Concentrations by race/ethnic group ..262

Table 2.30.a.1 Plasma eicosadienoic acid (20:2n-6): Concentrations ........................................264

Figure 2.30.a Plasma eicosadienoic acid (20:2n-6): Concentrations by age group....................265

Tables 2.30.a.2–5 Plasma eicosadienoic acid (20:2n-6): Concentrations by race/ethnic group........266

Table 2.31.a.1 Plasma homo-gamma-linolenic acid (20:3n-6): Concentrations..........................268

Figure 2.31.a Plasma homo-gamma-linolenic acid (20:3n-6): Concentrations by age group .....269

Tables 2.31.a.2–5 Plasma homo-gamma-linolenic acid (20:3n-6): Concentrations by race/ethnic 

group.................................................................................................................270

Table 2.32.a.1 Plasma arachidonic acid (20:4n-6): Concentrations...........................................272

Figure 2.32.a Plasma arachidonic acid (20:4n-6): Concentrations by age group......................273

Tables 2.32.a.2–5 Plasma arachidonic acid (20:4n-6): Concentrations by race/ethnic group..........274

Table 2.33.a.1 Plasma eicosapentaenoic acid (20:5n-3): Concentrations...................................276

Figure 2.33.a Plasma eicosapentaenoic acid (20:5n-3): Concentrations by age group ..............277

Tables 2.33.a.2–5 Plasma eicosapentaenoic acid (20:5n-3): Concentrations by race/ethnic group ..278

Table 2.34.a.1 Plasma docosatetraenoic acid (22:4n-6): Concentrations...................................280

Figure 2.34.a Plasma docosatetraenoic acid (22:4n-6): Concentrations by age group ..............281

Tables 2.34.a.2–5 Plasma docosatetraenoic acid (22:4n-6): Concentrations by race/ethnic group ..282
vi 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.35.a.1 Plasma docosapentaenoic-3 acid (22:5n-3): Concentrations ..............................284

Figure 2.35.a Plasma docosapentaenoic-3 acid (22:5n-3): Concentrations by age group .........285

Tables 2.35.a.2–5 Plasma docosapentaenoic-3 acid (22:5n-3): Concentrations by race/ethnic 

group.................................................................................................................286

Table 2.36.a.1 Plasma docosapentaenoic-6 acid (22:5n-6): Concentrations ..............................288

Figure 2.36.a Plasma docosapentaenoic-6 acid (22:5n-6): Concentrations by age group .........289

Tables 2.36.a.2–5 Plasma docosapentaenoic-6 acid (22:5n-6): Concentrations by race/ethnic 

group.................................................................................................................290

Table 2.37.a.1 Plasma docosahexaenoic acid (22:6n-3): Concentrations...................................292

Figure 2.37.a Plasma docosahexaenoic acid (22:6n-3): Concentrations by age group ..............293

Tables 2.37.a.2–5 Plasma docosahexaenoic acid (22:6n-3): Concentrations by race/ethnic 

group.................................................................................................................294

References................................................................................................................... 296

3 Trace Elements................................................................................................................299

Iron-Status Indicators .................................................................................................... 300

Background Information............................................................................................. 300

Highlights................................................................................................................... 303

Figure H.3.a Age-adjusted prevalence estimates of low body iron in 

U.S. children and women by race/ethnicity, NHANES 2003–2006 ..................303

Figure H.3.b Prevalence estimates of low serum ferritin, high serum soluble 

transferrin receptor, and low serum body iron in U.S. women 

12–49 years of age, NHANES 2003–2006........................................................303

Figure H.3.c Age-adjusted prevalence estimates of low and high serum ferritin 

in U.S. men and women aged12–49 years, NHANES 1999–2006....................304

Figure H.3.d Age-adjusted geometric mean concentrations of serum ferritin 

in U.S. women aged 12–49 years by race/ethnicity, NHANES 1988–2006.......305

Detailed Observations................................................................................................. 305

Table 3.1.a.1 Serum ferritin: Concentrations..........................................................................308

Figure 3.1.a Serum ferritin: Concentrations by age group .....................................................309

Tables 3.1.a.2–5 Serum ferritin: Concentrations by race/ethnic group .........................................310

Table 3.1.b Serum ferritin: Concentrations by survey cycle .................................................312

Figure 3.1.b Serum ferritin: Concentrations by survey cycle .................................................313

Table 3.1.c.1 Serum ferritin: Prevalence (< 12 ng/mL for children).........................................314

Table 3.1.c.2 Serum ferritin: Prevalence (< 15 ng/mL for women)..........................................315

Table 3.1.c.3 Serum ferritin: Prevalence (> 150 ng/mL for women)........................................316

Table 3.1.d.1 Serum ferritin: Prevalence by survey cycle (< 12 ng/mL for children) ................317

Table 3.1.d.2 Serum ferritin: Prevalence by survey cycle (< 15 ng/mL for women) .................318

Table 3.1.d.3 Serum ferritin: Prevalence by survey cycle (< 15 ng/mL for males) ....................319

Table 3.1.d.4 Serum ferritin: Prevalence by survey cycle (> 150 ng/mL for women) ...............320

Table 3.1.d.5 Serum ferritin: Prevalence by survey cycle (> 200 ng/mL for males) ..................321

Table 3.2.a.1 Serum soluble transferrin receptor: Concentrations ...........................................322

Figure 3.2.a Serum soluble transferrin receptor: Concentrations by age group ......................323

Tables 3.2.a.2–5 Serum soluble transferrin receptor: Concentrations by race/ethnic group ..........324

Table 3.2.b Serum soluble transferrin receptor: Concentrations by survey cycle ..................326

Figure 3.2.b Serum soluble transferrin receptor: Concentrations by survey cycle ..................327

Table 3.2.c Serum soluble transferrin receptor: Prevalence (> 4.4 mg/L for women) ............328

Table 3.2.d Serum soluble transferrin receptor: Prevalence by survey cycle (> 4.4 mg/L for 

women) ............................................................................................................329

Table 3.3.a.1 Body iron: Concentrations ................................................................................330

Figure 3.3.a Body iron: Concentrations by age group............................................................331

Tables 3.3.a.2–5 Body iron: Concentrations by race/ethnic group ...............................................332

Table 3.3.b Body iron: Concentrations by survey cycle .......................................................334

Figure 3.3.b Body iron: Concentrations by survey cycle .......................................................335

Table 3.3.c.1 Body iron: Prevalence (< 0 mg/kg for children) .................................................336

Table 3.3.c.2 Body iron: Prevalence (< 0 mg/kg for women)...................................................337
Table of Contents vii

Table 3.3.d.1 Body iron: Prevalence by survey cycle (< 0 mg/kg for children) ........................338

Table 3.3.d.2 Body iron: Prevalence by survey cycle (< 0 mg/kg for women) ..........................339

References................................................................................................................... 340

Iodine ............................................................................................................................ 342

Background Information............................................................................................. 342

Highlights................................................................................................................... 344

Figure H.3.e Median concentrations of urinary iodine in the U.S. population 

aged 6 years and older by age group and gender, NHANES 2001–2006............344

Figure H.3.f Age-adjusted geometric mean concentrations of urinary iodine 

in the U.S. population aged 6 years and older by gender or 

race/ethnicity, NHANES 1988–2006................................................................345

Detailed Observations................................................................................................. 345

Table 3.4.a.1 Urinary iodine: Concentrations.........................................................................346

Figure 3.4.a Urinary iodine: Concentrations by age group ....................................................347

Tables 3.4.a.2–5 Urinary iodine: Concentrations by race/ethnic group ........................................348

Table 3.4.b Urinary iodine: Concentrations by survey cycle ................................................350

Figure 3.4.b Urinary iodine: Concentrations by survey cycle ................................................351

Table 3.5.a.1 Urinary iodine (crea corr)*: Concentrations.......................................................352

Figure 3.5.a Urinary iodine (crea corr): Concentrations by age group ...................................353

Tables 3.5.a.2–5 Urinary iodine (crea corr): Concentrations by race/ethnic group .......................354

Table 3.5.b Urinary iodine (crea corr): Concentrations by survey cycle ...............................356

Figure 3.5.b Urinary iodine (crea corr): Concentrations by survey cycle ...............................357

References................................................................................................................... 358

4 Isoflavones and Lignans..................................................................................................361

Background Information............................................................................................. 362

Highlights................................................................................................................... 364

Figure H.4.a Geometric mean concentrations of urinary isoflavones and lignans 

in the U.S. population aged 6 years and older, NHANES 2003–2006...............365

Detailed Observations................................................................................................. 365

Table 4.1.a.1 Urinary genistein: Concentrations.....................................................................366

Figure 4.1.a Urinary genistein: Concentrations by age group ................................................367

Table 4.1.a.2–5 Urinary genistein: Concentrations by race/ethnic group ....................................368

Table 4.1.b Urinary genistein: Concentrations by survey cycle ............................................370

Figure 4.1.b Urinary genistein: Concentrations by survey cycle ............................................371

Table 4.2.a.1 Urinary genistein (crea corr): Concentrations ....................................................372

Figure 4.2.a Urinary genistein (crea corr): Concentrations by age group ...............................373

Tables 4.2.a.2–5 Urinary genistein (crea corr): Concentrations by race/ethnic group ...................374

Table 4.2.b Urinary genistein (crea corr): Concentrations by survey cycle ...........................376

Figure 4.2.b Urinary genistein (crea corr): Concentrations by survey cycle ...........................377

Table 4.3.a.1 Urinary daidzein: Concentrations......................................................................378

Figure 4.3.a Urinary daidzein: Concentrations by age group .................................................379

Tables 4.3.a.2–5 Urinary daidzein: Concentrations by race/ethnic group.....................................380

Table 4.3.b Urinary daidzein: Concentrations by survey cycle .............................................382

Figure 4.3.b Urinary daidzein: Concentrations by survey cycle .............................................383

Table 4.4.a.1 Urinary daidzein (crea corr): Concentrations.....................................................384

Figure 4.4.a Urinary daidzein (crea corr): Concentrations by age group ................................385

Tables 4.4.a.2–5 Urinary daidzein (crea corr): Concentrations by race/ethnic group ....................386

Table 4.4.b Urinary daidzein (crea corr): Concentrations by survey cycle ............................388

Figure 4.4.b Urinary daidzein (crea corr): Concentrations by survey cycle ............................389

Table 4.5.a.1 Urinary equol: Concentrations ..........................................................................390

Figure 4.5.a Urinary equol: Concentrations by age group .....................................................391

Tables 4.5.a.2–5 Urinary equol: Concentrations by race/ethnic group .........................................392

Table 4.5.b Urinary equol: Concentrations by survey cycle .................................................394

Figure 4.5.b Urinary equol: Concentrations by survey cycle .................................................395
viii 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.6.a.1 Urinary equol (crea corr): Concentrations .........................................................396

Figure 4.6.a Urinary equol (crea corr): Concentrations by age group.....................................397

Tables 4.6.a.2–5 Urinary equol (crea corr): Concentrations by race/ethnic group.........................398

Table 4.6.b Urinary equol (crea corr): Concentrations by survey cycle ................................400

Figure 4.6.b Urinary equol (crea corr): Concentrations by survey cycle ................................401

Table 4.7.a.1 Urinary ODMA**: Concentrations ...................................................................402

Figure 4.7.a Urinary ODMA: Concentrations by age group..................................................403

Tables 4.7.a.2–5 Urinary ODMA: Concentrations by race/ethnic group .....................................404

Table 4.7.b Urinary ODMA: Concentrations by survey cycle .............................................406

Figure 4.7.b Urinary ODMA: Concentrations by survey cycle .............................................407

Table 4.8.a.1 Urinary ODMA (crea corr): Concentrations......................................................408

Figure 4.8.a Urinary ODMA (crea corr): Concentrations by age group.................................409

Tables 4.8.a.2–5 Urinary ODMA (crea corr): Concentrations by race/ethnic group.....................410

Table 4.8.b Urinary ODMA (crea corr): Concentrations by survey cycle .............................412

Figure 4.8.b Urinary ODMA (crea corr): Concentrations by survey cycle .............................413

Table 4.9.a.1 Urinary enterodiol: Concentrations...................................................................414

Figure 4.9.a Urinary enterodiol: Concentrations by age group ..............................................415

Tables 4.9.a.2–5 Urinary enterodiol: Concentrations by race/ethnic group ..................................416

Table 4.9.b Urinary enterodiol: Concentrations by survey cycle ..........................................418

Figure 4.9.b Urinary enterodiol: Concentrations by survey cycle...........................................419

Table 4.10.a.1 Urinary enterodiol (crea corr): Concentrations ..................................................420

Figure 4.10.a Urinary enterodiol (crea corr): Concentrations by age group .............................421

Tables 4.10.a.2–5 Urinary enterodiol (crea corr): Concentrations by race/ethnic group .................422

Table 4.10.b Urinary enterodiol (crea corr): Concentrations by survey cycle .........................424

Figure 4.10.b Urinary enterodiol (crea corr): Concentrations by survey cycle..........................425

Table 4.11.a.1 Urinary enterolactone: Concentrations..............................................................426

Figure 4.11.a Urinary enterolactone: Concentrations by age group .........................................427

Tables 4.11.a.2–5 Urinary enterolactone: Concentrations by race/ethnic group .............................428

Table 4.11.b Urinary enterolactone: Concentrations by survey cycle .....................................430

Figure 4.11.b Urinary enterolactone: Concentrations by survey cycle......................................431

Table 4.12.a.1 Urinary enterolactone (crea corr): Concentrations.............................................432

Figure 4.12.a Urinary enterolactone (crea corr): Concentrations by age group ........................433

Tables 4.12.a.2–5 Urinary enterolactone (crea corr): Concentrations by race/ethnic group ............434

Table 4.12.b Urinary enterolactone (crea corr): Concentrations by survey cycle.....................436

Figure 4.12.b Urinary enterolactone (crea corr): Concentrations by survey cycle.....................437

References................................................................................................................... 438

5 Acrylamide Hemoglobin Adducts...................................................................................443

Background Information............................................................................................. 444

Highlights................................................................................................................... 445

Figure H.5.a Geometric mean glycidamide-to-acrylamide hemoglobin adduct ratio 

in the U.S. population aged 3 years and older, NHANES 2003–2004...............446

Detailed Observations................................................................................................. 446

Table 5.1.a.1 Acrylamide hemoglobin adduct: Concentrations...............................................448

Figure 5.1.a Acrylamide hemoglobin adduct: Concentrations by age group ..........................449

Tables 5.1.a.2–5 Acrylamide hemoglobin adduct: Concentrations by race/ethnic group ..............450

Table 5.2.a.1 Glycidamide hemoglobin adduct: Concentrations.............................................452

Figure 5.2.a Glycidamide hemoglobin adduct: Concentrations by age group ........................453

Tables 5.2.a.2–5 Glycidamide hemoglobin adduct: Concentrations by race/ethnic group ............454

Table 5.3.a.1 Glycidamide-to-acrylamide hemoglobin adduct ratio: Concentrations ..............456

Figure 5.3.a Glycidamide-to-acrylamide hemoglobin adduct ratio: Concentrations 

by age group......................................................................................................457

Tables 5.3.a.2–5 Glycidamide-to-acrylamide hemoglobin adduct ratio: Concentrations 

by race/ethnic group..........................................................................................458
Table of Contents ix

References................................................................................................................... 461

Appendices.........................................................................................................................465

Appendix A: NHANES Reports Related to Nutritional Status.................................... 466

Appendix B: Information Presented in the Report....................................................... 468

Appendix C: Cutoff Values Used to Generate Prevalence Estimates............................. 470

Appendix D: References for Analytical Methods for Biochemical Indicators ............... 471

Appendix E: Confidence Interval Estimation for Percentiles........................................ 473

Appendix F: Limit of Detection Table......................................................................... 478

Appendix G: Selected References of Descriptive NHANES Papers on 

Diet-and-Nutrition Biochemical Indicators .......................................................... 480

* crea corr, creatinine corrected

** ODMA, O-desmethylangolensin
x 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population
1

Introduction

•	 Background

•	 Addressing Data Needs

•	 Public Health Uses

•	 Data Presented for Each Biochemical Indicator

•	 Interpreting the Data

•	 Useful Sources of Information about Using Nutrition 

Monitoring to Interpret Data

•	 The National Health and Nutrition Examination 

Survey (NHANES)

•	 Data Analysis

•	 References

Introduction
2 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Introduction

Background

The National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population 

is a series of publications that provide ongoing assessment of the U.S. population’s nutritional 

status by measuring blood or urine concentrations of diet-and-nutrition biochemical indicators. 

The Centers for Disease Control and Prevention’s (CDC) Division of Laboratory Sciences at the 

National Center for Environmental Health (NCEH/DLS) conducted the laboratory analyses 

for 58 biochemical indicators presented in this 2012 report, which is the second in this series. 

CDC measured these indicators in specimens from a representative sample of the U.S. population 

during all or part of the four-year period from 2003 through 2006. Where available, data are also 

presented on changes of biochemical indicator concentrations over time since 1999. Similarly, 

data are also presented on the prevalence of low or high biochemical indicator concentrations 

during 2003–2006, and on changes in the prevalence over time since 1999. The first report of this 

series was published in July 2008 and contains information on 27 biochemical indicators from 

all or part of the four-year period from 1999 through 2002. Both reports can be accessed online: 

http://www.cdc.gov/nutritionreport.

Characteristic First report, 2008 Second report, 2012

Years of NHANES covered 1999–2002 2003–2006

Number of indicators covered 27 58

Concentrations by race/ethnic group Yes Yes

Central 95% reference intervals No Yes

Graphic representation of age patterns No Yes

Concentrations over time No Yes (1999-2006)

Prevalence estimates No Yes

Prevalence estimates over time No Yes (1999-2006)

CDC’s National Health and Nutrition Examination Survey (NHANES), conducted by the 

National Center for Health Statistics (NCHS), collected the specimens for this report. NHANES 

is a series of surveys designed to collect data on the health and nutritional status of the U.S. 

population. This report covers biochemical measurements—one important facet in the assessment 

of the U.S. population’s nutritional status. Other nutrition-related aspects from NHANES, 

such as dietary intake, supplement usage, hematologic measurements, and anthropometric body 

measurements are not covered.

In this report, a biochemical indicator means a nutrient (e.g., vitamin, fatty acid, trace element), 

a metabolite (e.g., homocysteine, methylmalonic acid), or a dietary indicator with potential 

health relevance (e.g., isoflavone, lignan) measured in blood or urine. Although most biochemical 

indicators presented in this report enter the human body from foods or supplements, the body 

itself produces some indicators in response to dietary intake or environmental exposure. Blood 

and urine concentrations reflect the amount of nutrients and dietary compounds actually in the 

body or passing through the body from all these sources.
Introduction 3

The biochemical indicator sections and new biochemical indicators covered in this report are:

Biochemical indicator sections New biochemical indicators

•	 Water-soluble vitamins •	 Vitamin B6

•	 Fat-soluble vitamins and nutrients •	 Vitamin C

•	 Trace elements (iron indicators and iodine) •	 Fatty acids

•	 Isoflavones and lignans •	 Iron status: Transferrin receptor and body iron

•	 Acrylamide hemoglobin adducts •	 Acrylamide hemoglobin adducts

Addressing Data Needs

This report is the second CDC product containing reference information on NCEH/DLS 

measurement data for a wide range of biochemical indicators of diet and nutrition from the most 

recent continuous NHANES survey, starting in 1999. In this comprehensive report, information 

on changes in concentrations of a large number of biochemical indicators during 1999–2006 

is presented for the first time. Prevalence information on low or high biochemical indicator 

concentrations is also presented for the first time.

NCHS has historically released or commissioned a variety of products presenting NHANES 

results. Among these are Data Briefs, Data Tables, Advance Data, Series Reports, and Reports 

through the Life Sciences Research Office (LSRO). NHANES Series Reports (mainly Series 

11) and LSRO Reports from surveys prior to the continuous NHANES have been of particular 

value to the nutrition community (see Appendix A). The NHANES Web site provides current 

information on results and products from this survey: http://www.cdc.gov/nchs/about/major/

nhanes/survey_results_and_products.htm. 

Public Health Uses

This report’s primary objective is to inform public health scientists and policy makers about the 

concentrations of biochemical indicators of diet and nutrition in the general U.S. population and 

in selected subpopulations. These data will help physicians, scientists, and public health offcials 

assess inadequate or excess intake and will inform analyses on the relation between biochemical 

indicators and health outcomes. Other objectives and potential public health uses of the 

information include

•	 Establishing and improving on existing population reference levels that can be used to 

determine whether an individual or a group has an unusually high or low concentration 

of a diet-and-nutrition biochemical indicator.

•	 Determining whether the nutritional status of special population groups, such as 

minorities, children, women of childbearing age, or the elderly, is different from that of 

other groups, or whether such nutritional status needs improvement.

•	 Tracking trends over time in the population’s biochemical indicator concentrations.

•	 Assessing the effectiveness of public health efforts to improve the diet and nutritional 

status of the U.S. population.

•	 Guide research to perform more in-depth analyses of the NHANES data and to 

generate hypotheses for future nutrition and human health studies.
4 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Data Presented for Each Biochemical Indicator

This report contains tables and figures of descriptive statistics on the distribution of blood and 

urine concentrations during all or part of the four-year period from 2003 through 2006 for 

each diet-and-nutrition biochemical indicator. Statistics include unadjusted geometric means 

and selected percentiles with confidence intervals. For some biochemical indicators, additional 

information is included, as available, in the form of

•	 Tables and figures describing biochemical indicator concentrations across survey cycles 

during all or part of the eight-year period from 1999 through 2006. Statistics include 

unadjusted geometric means and selected percentiles with confidence intervals. 

•	 Tables describing the prevalence of low or high concentrations of selected biochemical 

indicators during all or part of the four-year period from 2003 through 2006 and tables 

describing the prevalence across survey cycles during all or part of the eight-year period 

from 1999 through 2006. Statistics include unadjusted percentages with confidence 

intervals and estimated total number of persons affected.

See Appendix B for an overview of the type of information presented for each biochemical 

indicator. The data are grouped by age, gender, and race/ethnicity. The majority of the 

biochemical indicators reviewed in this report, with the exception of vitamin C and body iron, 

have a long upper tail (skewed right). For these biochemical indicators, a geometric mean provides 

a better estimate of central tendency because it is less influenced by high values than is the 

arithmetic mean. However, the arithmetic mean is presented for vitamin C and body iron as the 

distributions for these biochemical indicators were reasonably symmetric. Scientists can use the 

presented percentile levels to determine those serum, blood, or urine indicator concentrations 

common to people in the U.S. population and those that are unusual. Frequently, the central 

95% reference interval (2.5th to 97.5th percentile) is used to describe normal concentrations in 

a population. Concentrations outside the reference interval are considered unusual. For urine 

measurements, data are shown for both the concentration and for the concentration corrected for 

the urinary creatinine level. 

We present the following information for each biochemical indicator during all or part of 2003–

2006:

•	 A table that presents the geometric mean and selected percentile (2.5th–97.5th, so called 

central 95% reference interval) concentrations by age, gender, or race/ethnicity (1-level 

stratified).

•	 A figure that presents the geometric mean concentrations by age and gender or by age 

and race/ethnicity (2-level stratified). 

•	 Four detailed tables that present the geometric mean and selected percentile (5th or 10th, 

50th, 90th or 95th) concentrations by age, gender, and race/ethnicity (3-level stratified). 

The first table is for the overall U.S. population stratified by age and gender, while the 

next three tables present data for each racial/ethnic group (Mexican American, nonHispanic black, and non-Hispanic white) stratified by age and gender.

If data are available for multiple two-year survey cycles from 1999–2006, we present tables with 

geometric mean and selected percentile (5th–95th) concentrations by age, gender, or race/ethnicity 

for each available two-year survey cycle, as well as corresponding figures for selected percentiles 

(1-level stratified).
Introduction 5

For biochemical indicators that have accepted cutoff values for low or high concentrations or 

for both (e.g., folate, vitamins A, B6, B12, C, D, E, ferritin, iodine)—suggesting deficiency or 

excess of certain micronutrients—we present tables with prevalence estimates by age, gender, or 

race/ethnicity during all or part of 2003–2006 (1-level stratified). We also present tables with 

prevalence estimates by age, gender, or race/ethnicity for each available two-year survey cycle from 

1999–2006 to allow evaluation of changes in prevalence estimates over time (1-level stratified). 

See Appendix C for a complete listing of the cutoff values and populations described in this 

report.

Background text provides general information for each indicator to aid with interpreting the data. 

To address sources of these nutrients, biochemical pathways in the body, and known health 

effects, the text contains a brief overview about each indicator.

Each chapter contains highlights followed by detailed observations that are derived from this report’s 

data tables and figures. 

The highlights are presented directly after the background text. They summarize important 

observations and discuss them in a public health context. For example, we present figures 

highlighting prevalence information by demographic subgroups. Where long-term trending 

information beyond the continuous NHANES is available and of public health interest, we 

present figures showing changes in biochemical indicator concentrations from NHANES III 

(1988–1994) to NHANES 1999–2002 and NHANES 2003–2006. The detailed observations

describe selected categorical differences between demographic subgroups derived from the data 

tables and figures that follow next. Each chapter is concluded by a list of pertinent references.

Interpreting the Data

Blood or urine concentrations of biochemical indicators can help in assessing the adequacy of 

intake for the U.S. population. These measurements indicate cumulative intakes from foods, some 

fortified with micronutrients (e.g., iron, thiamin, riboflavin, niacin, folate, vitamin A, vitamin 

D), and from dietary supplements that contain vitamins, minerals, or both. However, blood or 

urine concentrations of biochemical indicators can also be influenced by factors other than diet, 

such as various diseases or exposures. For those nutrients without defined adequate intakes (e.g., 

carotenoids, isoflavones), biochemical indicators are useful for assessing intake without regard to 

adequacy.

Dietary deficiencies are well documented, and they have characteristic signs and symptoms. In 

addition, recent findings have determined that less than optimal biochemical concentrations 

(representing suboptimal status) have been associated with risks of adverse health effects. These 

health effects include cardiovascular disease, stroke, impaired cognitive function, cancer, eye 

diseases, poor bone health, and other conditions. Adverse health effects, including toxicity, are also 

possible from consuming excess amounts of certain nutrients and data to assist in the assessment 

of excessive intake is a feature of this report. Determining the concentrations of a biochemical 

indicator that may indicate risk for disease and the concentrations that are of negligible health 

concern requires future research studies that are separate from this report. In collaboration with 

other agencies and institutions, CDC encourages, and itself conducts research on the relationship 

between biochemical indicators and health effects.
6 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

This report contains unadjusted geometric means, 

selected percentiles, and prevalence estimates of low or 

high concentrations of diet-and-nutrition biochemical 

indicators for the civilian, noninstitutionalized U.S. 

population. A limited interpretation of relative 

differences between population groups is possible by 

identifying groups with nonoverlapping confidence 

intervals. However, one should be careful about 

interpreting the observed differences as causal. 

The intent is to describe the characteristics of the 

population and of selected subgroups, not to explain 

why the groups display certain characteristics or why 

they differ from each other. Furthermore, differences 

in biochemical indicator concentrations of selected 

subgroups do not necessarily imply health status problems. And for several reasons, one should use 

caution when drawing temporal conclusions from comparisons of serial cross-sectional NHANES 

survey cycles. One of these reasons is that different or improved methods of measurement may 

be employed across the NHANES survey cycles. Another reason is that there are demographic 

changes to the U.S. population over time. Finally, sampling differences could explain some of the 

observed changes from one cycle to the next. More in-depth statistical analyses, such as developing 

models to adjust simultaneously for many covariates and taking into consideration interactions 

between two or more variables, are beyond the scope of this report. Nonetheless, unadjusted 

geometric means, selected percentiles, and prevalence estimates provided in this report are useful 

to summarize reference information for blood or urine concentrations of diet-and-nutrition 

biochemical indicators for the civilian, noninstitutionalized population in the United States and 

selected subgroups. We hope that the report will stimulate scientists to examine the data further 

through analyzing the raw data available at: http://www.cdc.gov/nchs/nhanes.htm.

Laboratories may use different methods for measuring the indicators reported here. However, 

different methods may result in different method-specific reference intervals. Consequently, to 

apply these results, health science professionals should check with their particular laboratory to be 

sure that their methods compare closely to those used in this report (see Appendix D).

Sources of Information on Nutrition Monitoring to Help Interpret 

the Data

Information about dietary intake is critical to research examining the reasons for nutritional 

inadequacies. Such information is also critical to programs seeking to improve diet and nutritional 

status. Selected NCHS Advance Data Reports provide useful overviews (see Appendix A). Also of value 

are the U.S. Department of Agriculture’s (USDA) databases on food surveys and food composition: 

What We Eat in America (WWEIA) is the dietary intake interview section of NHANES (http://

www.ars.usda.gov/foodsurvey).

The Food and Nutrient Database for Dietary Studies (FNDDS) (http://www.ars.usda.gov/

Services/docs.htm?docid=12089) is a database of foods, their nutrient values, and weights for 

typical food portions. This database is used to generate data for the WWEIA survey through 

application of the nutrient values from the National Nutrient Database for Standard Reference 

(http://www.ars.usda.gov/Services/docs.htm?docid=8964).
Introduction 7

The National Health and Nutrition Examination Survey (NHANES)

CDC laboratory scientists used biological specimens obtained from NHANES participants to 

measure biochemical indicators of diet and nutrition for this publication. NHANES is a series of 

NCHS-conducted surveys designed to collect data on the health and nutritional status of the U.S. 

population. This is the only national survey that collects biological samples. The NHANES surveys 

began in 1960 with the first Health Examination Survey (HES 1). The nutritional component was 

added in the early 1970s in NHANES I. In 1999, NHANES became a continuous survey, sampling 

the U.S. population annually and releasing the data in two-year cycles. 

NHANES collects information on a wide range of health-related behaviors, conducts physical 

examinations, and collects samples for laboratory tests. Because of physical examination and 

biological measures, NHANES is unique in its ability to examine public health issues in the U.S. 

population, such as risk factors for cardiovascular disease. To select a representative sample of the 

civilian, noninstitutionalized population in the United States, the survey sampling plan follows 

a complex, stratified, multistage, probability-cluster design. The civilian, noninstitutionalized 

population consists of persons who are neither in the military nor institutionalized (e.g., they are 

not residents of nursing homes, college dormitories, or prisons). 

The NHANES protocol includes a home interview followed by a standardized physical 

examination at a mobile examination center. As part of the examination, for participants aged 1 

year and older, blood is obtained by venipuncture. Urine specimens are collected from participants 

aged 6 years and older. By design, approximately half of the participants are evaluated after an 

overnight fast; for the other half of the participants, there is approximately an equal distribution 

between those who fasted less than 3 hours and those who fasted between 3 and 8 hours before 

providing a biological sample. Because weather can adversely affect the mobile examination 

centers, data are collected in northern latitudes in summer and in southern latitudes in winter. 

This seasonal-latitude structure might indirectly affect biochemical indicators.

Additional detailed information about the design and conduct of the NHANES survey is available 

at http://www.cdc.gov/nchs/nhanes.htm. Information about how biological specimens are 

collected is available at (http://www.cdc.gov/nchs/data/nhanes/blood.pdf) and included in the 

Laboratory Procedures Manual at http://www.cdc.gov/nchs/data/nhanes/lab1-6.pdf and at http://

www.cdc.gov/nchs/data/nhanes/lab7-11.pdf.

Data Analysis

NCHS has developed a comprehensive Web-based tutorial (http://www.cdc.gov/nchs/tutorials/

Nhanes/index.htm) to help users better understand the complex survey design and to help them 

analyze NHANES data.

Because the NHANES sample design is a complex, multistage probability sample, officials 

use sample weights when estimating the mean or other descriptive metrics. These weights are 

post-stratified to the U.S. Census Bureau estimates of the U.S. population to adjust for the 

unequal probability of selection into the survey and possible bias resulting from nonresponse. 

Demographic data files released by NCHS for each NHANES two-year survey cycle include a 

two-year interview weight and a medical examination weight. All estimates in this report use the 

appropriate medical examination weight. The selected medical examination weight depends on 

whether the specimens tested constitute a random subsample of all the eligible participants and 

how many survey cycles are combined to produce the estimate. 
8 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Combining data over multiple survey cycles can produce estimates with increased statistical 

reliability. In cases of combined estimates, new weights were constructed. For example, a four-year 

estimate for the years 2003–2006 was based on a four-year weight, which was created by assigning 

half the two-year weight for 2003–2004 or half the two-year weight for 2005–2006, depending 

when the person was sampled. 

Results are shown for the total population and by age group, gender, and race/ethnicity, as defined 

in NHANES. For these analyses, race/ethnicity is presented as Mexican American, non-Hispanic 

black, and non-Hispanic white. Other racial or ethnic groups are sampled, but the proportion 

of the total population represented by these other groups is not large enough to produce valid 

estimates. Thus, this report does not include separate estimates for other racial subcategories. The 

other racial/ethnic groups, however, are included in the overall estimates.

Data were analyzed by use of the statistical software package Statistical Analysis System (SAS, 

Version 9.2) and SUDAAN (Release 10.0). SUDAAN uses sample weights and calculates variance 

estimates that account for the complex survey design. Guidelines for the analysis of NHANES 

data are provided by NCHS at: http://www.cdc.gov/nchs/nhanes/nhanes2003-2004/analytical_

guidelines.htm.

Standard error estimates were calculated by use of the Taylor series (linearization) method within 

SUDAAN. The degrees of freedom for variance estimation are generated by subtracting the 

number of strata from the number of primary sampling units (PSUs). 

Geometric means were calculated by taking the log of each concentration, calculating the mean 

of those log values, then taking the antilog of that mean (the calculation can be done by use of 

any log base, such as 10 or e). The confidence interval uses the standard error and mean on the 

log scale and the appropriate critical value from the t-distribution to calculate upper and lower 

confidence limits on the log scale. The confidence intervals of geometric means in this report are 

based on taking the antilog of those upper and lower confidence intervals.

Percentile estimates were calculated by use of linear interpolation. Confidence intervals for 

percentiles were calculated by the Woodruff method (1952). This method uses the standard error 

of the empirical distribution function at the selected percentile and constructs a 95% confidence 

interval, followed by back-transforming by use of the inverse of the empirical distribution (see 

Appendix E for more details). We used the unweighted sample size and assumed an average 

design effect of 1.4 as the criteria to estimate percentiles of sufficient precision (U.S. Centers for 

Disease for Control and Prevention 1996; Table 1 in Appendix B). In order for percentiles to be 

considered reliable, at least 112 persons had to be represented to allow estimation of the 10th and 

90th percentiles, 224 persons for the 5th and 95th percentiles, and 448 persons for the 2.5th and 

97.5th percentiles. We flagged and footnoted percentiles where these requirements were not met.

Prevalence estimates for low or high concentrations of biochemical indicators are the weighted 

percentage of persons who fall below or above a predefined cutoff value (see Appendix C). The 

confidence intervals for prevalence estimates are based on a logit transformation that ensures 

the confidence interval limits cannot fall outside of 0 and 1. We used the relative standard error 

(RSE) as a criterion for prevalence estimates of sufficient precision. The RSE is calculated as a 

percentage by dividing the standard error of the estimate by the estimate value and multiplying by 

100. Prevalence estimates associated with a RSE between 30% and less than 40% are flagged and 

footnoted in this report. Estimates are not provided if they are associated with an RSE equal to or 

greater than 40%.
Introduction 9

Estimates of the total number of persons who met the definition of having low or high 

concentrations of biochemical indicators were generated by multiplying the weighted prevalence 

estimate by the population size of interest, derived from the current population survey (CPS) at 

the midpoint of the available two-year cycle. Confidence intervals for the estimated total, while 

not presented, are calculated by multiplying the population size of interest by the upper and 

lower limits of the 95% confidence interval for the weighted prevalence. CPS-based population 

tables for NHANES by age, gender, and race/ethnicity are on the NHANES Web page for a 

given survey cycle, available at http://www.cdc.gov/nchs/nhanes/response_rates_CPS.htm. When 

estimates of the total count are based on combined survey cycles (2003–2006), the 2003–2004 

CPS-based population table at the above link was used. 

Figures in the highlight section that present age-adjusted geometric mean concentrations from 

NHANES III (1988–1994), NHANES 1999–2002, and NHANES 2003–2006 or age-adjusted 

prevalence estimates by demographic subgroups have been generated in SUDAAN by use of agestandardizing proportions from the 2000 U.S. Census population (using direct standardization). 

Statistically significant differences between age-adjusted geometric means and age-adjusted 

prevalences were assessed through pairwise comparisons. A reader should take care when 

interpreting these age-adjusted figures in isolation. The magnitude of an age-adjusted geometric 

mean or age-adjusted prevalence is completely arbitrary, and it depends upon the chosen standard 

population. Additionally, age-adjusted geometric means or age-adjusted prevalences can mask 

important information about trends if age-specific rates do not have a consistent relationship. 

It is worth noting that while NHANES 1999–2004 provided a race/ethnicity variable that was 

an analytic link to the NHANES III race/ethnicity variable called RIDRETH2, this variable is 

not included in the NHANES 2005–2006 demographics file. Therefore, the codes of the race/

ethnicity variable called RIDRETH1 were used in displaying age-adjusted geometric means by 

race/ethnicity for NHANES 1999–2002 and NHANES 2003–2006. RIDRETH1 includes 

all multi-racial responses in the Other category; whereas, RIDRETH2 includes multi-racial 

responses for Non-Hispanics with primary race White or Black in the Non-Hispanic White or 

Non-Hispanic Black categories. This means that there are slightly fewer people coded as nonHispanic white and non-Hispanic black through RIDRETH1 than for RIDRETH2; however, 

this difference does not affect the Mexican American category.

The limit of detection (LOD) is the level at which the measurement has a 95% probability of 

being greater than zero (Taylor 1987). For calculation of geometric means, concentrations less 

than the LOD were assigned a value equal to the LOD divided by the square root of 2. If the 

proportion of results less than the LOD (< LOD) was greater than 40%, geometric means were 

not calculated. Percentile estimates less than the LOD were reported as “< LOD”. Most of the 

indicators had very few results below the LOD value, so that the choice of statistical analysis to 

handle these results makes little practical difference. There were a few exceptions, however (e.g., 

serum cis-beta-carotene, retinyl palmitate and retinyl stearate; urinary O-desmethylangolensin and 

equol), where a larger proportion of results were < LOD. Appendix F contains a table of LOD 

values for each biochemical indicator, as well as the unweighted percent of data values that were < 

LOD for each survey cycle. LOD values may change over the time period of the report as a result 

of changes in analytical methods. We used the higher of the two LOD values for the analysis of 

the combined four-year data for 2003–2006.
10 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Due to changes to analytical methods for plasma total homocysteine, serum 25-hydroxyvitamin 

D, and serum ferritin, an adjustment equation was applied to the data, as described in the 

NHANES documentation:

•	 http://www.cdc.gov/nchs/nhanes/nhanes1999-2000/LAB06.htm#Component_

Description

•	 http://www.cdc.gov/nchs/nhanes/nhanes2003-2004/L06VID_C.htm

•	 http://www.cdc.gov/nchs/nhanes/nhanes2003-2004/L06TFR_C.htm#Analytic_Notes.

For biochemical indicators measured in urine, we present separate tables for the concentration 

of the indicator expressed as “per volume of urine” (uncorrected table) and the concentration of 

the indicator expressed as “per gram of creatinine” (creatinine-corrected table). Comparison of 

an individual participant’s result to population data in the tables requires correction for urinary 

dilution; thus, an individual creatinine-corrected result is needed and should be compared 

to the creatinine-corrected data tables. Otherwise, health scientists may compare means and 

percentiles from other studies to the tables having either of the corresponding units. We used the 

uncorrected tables to compare urine concentrations across groups. Because instrument responses 

are measured in units of weight per volume, LOD calculations were performed by use of the 

concentration of the indicator expressed as per volume of urine. For this reason, LOD results for 

urine measurements in Appendix F are in weight per volume of urine. In the creatinine-corrected 

tables, a result for a geometric mean or a percentile was reported as < LOD if the corresponding 

geometric mean or percentile was < LOD in the uncorrected table. Thus, for example, if the 

5th percentile for males was < LOD in the uncorrected table, it would also be < LOD in the 

creatinine-corrected table.

References

Taylor JK. Quality assurance of chemical measurements. Chelsea (MI): Lewis Publishing; 1987.

U.S. Centers for Disease Control and Prevention. NHANES analytic guidelines, the Third National Health and 

Nutrition Examination Survey, NHANES III (1988–94). Hyattsville (MD): National Center for Health Statistics; 

October 1996 [cited 2011]. Available at: http://www.cdc.gov/nchs/data/nhanes/nhanes3/nh3gui.pdf. 

Woodruff RS. Confidence intervals for medians and other position measures. J Am Stat Assoc. 

1952;57:622–627.


1. Water-Soluble Vitamins 13

1. Water-Soluble Vitamins

B Vitamins and Related Biochemical Compounds

•	 Folate (serum and red blood cell)

•	 Vitamin B6

» Pyridoxal-5’-phosphate

» 4-Pyridoxic acid

•	 Vitamin B12

•	 Homocysteine

•	 Methylmalonic acid

Vitamin C (Ascorbic Acid)
14 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

B Vitamins and Related Biochemical Compounds

Background Information

Sources and Physiological Functions. Folate, vitamins B6, and B12 belong to the group of 

water-soluble B vitamins that occur naturally in food. Leafy green vegetables (such as spinach and 

turnip greens), fruits (such as citrus fruits and juices), and dried beans and peas are all natural 

sources of folate. Folic acid is the synthetic form of folate found in supplements and added 

to fortified foods. Because of wide consumption of fortified foods in the United States, these 

products have become an important contributor of folic acid to the U.S. diet. Folate functions as 

a coenzyme in single-carbon transfers in the metabolism of nucleic and amino acids. It is therefore 

especially important during periods of rapid cell division and growth, such as occurs during 

pregnancy and infancy.

The most abundant dietary sources of vitamin B6 are meats, whole grains (with the highest 

concentrations of B6 in the germ and aleuronic layer), vegetables, and nuts. Vitamin B6 is used as 

a cofactor for nearly 200 biochemical reactions in the human body, mostly related to amino acid 

metabolism. Its three major forms are pyridoxine (the major form in plants) and pyridoxal and 

pyridoxamine (the two most abundant forms in humans and animals); pyridoxal-5’-phosphate 

(PLP) is the most biologically active coenzyme form. 4-Pyridoxic acid (4PA) is the end product of 

vitamin B6 catabolism.

Vitamin B12 (cobalamin) is found naturally in animal foods, including fish, meat, poultry, eggs, 

milk, and milk products. For vegetarians, fortified breakfast cereals are a particularly valuable 

source of vitamin B12. The current Dietary Guidelines for Americans list vitamin B12 as a 

nutrient of concern for specific population groups. The guidelines recommend that persons 

50 years and older consume foods fortified with vitamin B12 or dietary supplements (U.S. 

Department of Agriculture and U.S. Department of Health and Human Services 2010). Vitamin 

B12 functions as a coenzyme for a critical methyl transfer reaction that converts homocysteine to 

methionine and for a separate reaction that converts L-methylmalonyl-coenzyme A to succinylcoenzyme A.

Homocysteine (Hcy) is an amino acid naturally found in the blood. Plasma Hcy concentrations 

are strongly influenced by diet as well as by genetic factors. Elevated concentrations of total 

Hcy (tHcy; the sum of free, protein-bound, and disulfides) are found in people whose folate, 

vitamin B12, or vitamin B6 status is suboptimal (Selhub 1993) and in people with impaired renal 

function (Wollensen 1999).

Methylmalonic acid (MMA) is a dicarboxylic acid naturally found in the blood. Plasma MMA 

concentrations are elevated when serum vitamin B12 concentrations are low or intermediate; such 

concentrations are therefore a useful diagnostic test for confirming vitamin B12 deficiency (Baik 

1999). As with plasma tHcy, MMA concentrations are also elevated in people with impaired renal 

function (Rasmussen 1990).

Health Effects. A chronic dietary deficiency of either folate or vitamin B12 causes macrocytic 

anemia, although strict dietary deficiencies are rare. Due to the wide abundance of vitamin B6 

in foods, dietary deficiencies of vitamin B6 are also rare. Signs of vitamin B6 deficiency include 

dermatitis, glossitis (inflammation of the tongue), depression, confusion, convulsions, and 

anemia. Symptoms do not appear immediately, however, for ~80% of the vitamin B6 in the 

body is stored in muscle tissue and will remain stable until intake has been low for several weeks 

(Coburn 1990). Certain drugs (e.g., alcohol, methotrexate, anticonvulsants, sulfa drugs) may 

interfere with the absorption or utilization of folate, and disorders of the small bowel that limit 
1. Water-Soluble Vitamins 15

absorption (e.g., Crohn’s disease, jejunal bypass surgery) can cause folate deficiency (Halsted 

1990). Drugs that react with carbonyl groups have the potential to interact with PLP. Isoniazid—

used in the treatment of tuberculosis—and L-DOPA have been shown to reduce plasma PLP 

concentrations, and a small decrease in vitamin B6 status has been seen in women taking highdose oral contraceptives (Institute of Medicine 1998). Most people who develop a vitamin 

B12 deficiency have an underlying stomach or intestinal disorder that limits the absorption of 

vitamin B12. Subtly reduced cognitive function resulting from early vitamin B12 deficiency is 

sometimes the only symptom of these intestinal disorders. Severe vitamin B12 deficiency can 

cause permanent nerve damage and dementia. Hematologic signs, however, are not always present 

in vitamin B12 deficiency, and hematologic signs and neurologic abnormalities can be inversely 

correlated (Baik 1999).

Clinical trials have shown that folic acid supplementation effectively reduces the number of neural 

tube birth defects (NTDs) (Czeizel 1992; MRC Vitamin Study Research Group 1991). Thus, 

the U.S. Public Health Service recommended that every woman who could become pregnant 

consume at least 400 micrograms (μg) of folic acid each day (U.S. Centers for Disease Control 

and Prevention 1992). This recommendation has also been incorporated into the current Dietary 

Guidelines for Americans, which list folate as a nutrient of concern for specific population groups 

(U.S. Department of Agriculture 2010). Since 1998, the U.S. Food and Drug Administration 

(FDA) has required the addition of folic acid to enriched breads, cereals, flours, corn meals, 

pastas, rice, and other grain products (U.S. Food and Drug Administration 1996). After the 

introduction of fortification, NTD rates have decreased by 36% (U.S. Centers for Disease 

Control and Prevention 2010); nevertheless, in the era of folic acid fortification, NTD rates are 

still highest among Hispanic women (Williams 2005). The higher prevalence in Hispanics could 

be due to their lower consumption of total folic acid, which is specifically true for less acculturated 

populations (Hamner 2011). This suggests that there may be factors in addition to folate status, 

such as genetic or environmental factors, that modulate NTD prevalence and possibly lead to 

higher folate requirements for some population groups. Recent observational studies have also 

suggested other potential benefits of the U.S. folic acid fortification, such as decreased prevalence 

of inadequate serum and RBC folate concentrations (Pfeiffer 2007), and declines in the 

incidence of stroke (Yang 2006) and neuroblastoma (French 2003). Potential roles of B vitamins 

in modulating the risk for diseases (e.g., heart disease, cancer, and cognitive impairment) are 

currently being studied. Two national health objectives that relate to folate and maternal, infant, 

and child health are part of the objectives for Healthy People 2020: Objective MICH HP2020-14 

(increase the proportion of women of childbearing potential with intake of at least 400 μg of folic 

acid from fortified foods or dietary supplements) and Objective MICH HP2020-15 (reduce the 

proportion of women of childbearing potential who have low red blood cell folate concentrations) 

(http://www.healthypeople.gov/HP2020/).

Intake Recommendations. The recommended dietary allowance (RDA) for both men and 

women is 400 μg per day of dietary folate equivalents (DFEs). DFEs adjust for the nearly 50% 

lower bioavailability of dietary folate compared to the bioavailability of folic acid: 1 mg of dietary 

folate equivalent equals 0.6 mg of folic acid from fortified food or from a supplement taken on an 

empty stomach (Institute of Medicine 1998). The RDA for vitamin B6 is 1.3 mg for both men and 

women (19–50 years), 1.7 mg for men and 1.5 mg for women aged 51 years and older, and 1.9 

mg for pregnant women (2.0 mg if lactating) (Institute of Medicine 1998). The RDA for vitamin 

B12 for adults is 2.4 μg per day. Because as many as 10 to 30% of older people may be unable to 

absorb naturally occurring vitamin B12, it is advisable for people older than 50 years to meet their 

RDA mainly by consuming foods fortified with vitamin B12 or by taking a supplement containing 

vitamin B12. People with vitamin B12 deficiency caused by a lack of intrinsic factor or intestinal 

malabsorption require parenteral B12 treatment (Institute of Medicine 1998).
16 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Prolonged consumption of very high daily intakes of folic acid has the potential to delay the 

diagnosis of anemia among adults with vitamin B12 deficiency. This may result in increased 

risk of progressive, unrecognized neurological damage from untreated vitamin B12 deficiency. 

Consequently, the Institute of Medicine (1998) set the Tolerable Upper Intake Level (UL) for 

folic acid intake for adults (aged 19 years and older) at 1000 μg per day. The UL is defined as 

the “maximum daily intake levels at which no risk of adverse health effects is expected for almost 

all individuals in the general population—including sensitive individuals—when the nutrient is 

consumed over long periods of time” (Institute of Medicine 2000). Because no data were available 

for children, the Institute of Medicine used the UL for adults adjusted by weight: 300–800 mg 

per day, depending on the age group. Folate intake from food 

is not associated with any health risk. The UL for vitamin B6 

for adults is 100 mg per day (Institute of Medicine 1998). If 

more is ingested through supplements, sensory neuropathy, 

dermatological lesions, and reversible nerve damage to the 

arms and legs can occur. No adverse effects have been seen, 

however, from getting large amounts of vitamin B6 through 

food sources (Institute of Medicine 1998). No adverse effects 

have been associated with excess vitamin B12 intake from food 

or supplements in healthy individuals, and no UL has been set 

(Institute of Medicine 1998).

Biochemical Indicators and Methods. Folate status can be 

assessed by measuring serum or plasma folate, which provides 

information on recent intake, and red blood cell (RBC) folate, 

indicative of body folate stores and long-term nutritional status. 

Vitamin B6 status is typically assessed by measuring the level of 

one or more of the B6 vitamers in serum or plasma. Serum PLP 

is generally viewed as the best single indicator of status. Serum 

or urinary 4PA, the end product of vitamin B6 catabolism, is an 

indicator of recent intake. Vitamin B12 status can be assessed by measuring serum or plasma total 

cobalamins or serum holo-transcobalamin II, the transport protein of absorbed cobalamin. Urinary 

or serum MMA is a specific functional indicator of vitamin B12 status. Plasma tHcy is a functional 

indicator of folate, vitamin B6, and/or B12 status, but it is not specific for either vitamin. As B 

vitamin concentrations decrease, plasma tHcy concentrations increase. 

Clinical laboratories typically use conventional units for measuring concentrations of folate 

(nanograms per milliliter [ng/mL]) and vitamin B12 (picograms [pg]/mL) and international 

system (SI) units for vitamin B6 (nanomole per liter [nmol/L]), tHcy (micromole [mmol]/L), and 

MMA (nmol/L). Conversion factors to SI units are as follows: 1 ng/mL = 2.266 nmol/L for folate 

and 1 pg/mL = 0.738 picomol (pmol)/L for vitamin B12.

Traditionally, folate has been measured by microbiologic assay; however, in clinical settings, 

radioprotein-binding assays or commercial non-radio-protein-binding assays on automated 

clinical analyzers offering high throughput are used (Shane 2011). In research settings, 

chromatography-based methods, nowadays coupled to tandem mass spectrometry (LC-MS/MS), 

are often used to measure individual forms of folate in serum or whole blood (Pfeiffer 2010). 

International reference materials for serum folate from the U.S. National Institute of Standards 

and Technology (NIST) and the United Kingdom National Institute for Biological Standards and 

Control (NIBSC), with certified or reference values by higher-order reference methods (LC-MS/

MS), have been available only for the last few years: NIST SRM 1955 and 1950, and NIBSC 

03/178. A reference material for whole blood folate has been available from the NIBSC (95/528) 
1. Water-Soluble Vitamins 17

for several years; however, the value assignment for this material was by consensus of various 

protein-binding and microbiological assays. Because of observed method differences in measuring 

folate concentrations (Gunter 1996, Pfeiffer 2010), caution should be used in comparing other 

datasets to the tables in this report. Method-specific cutoff values and reference intervals for use in 

medical diagnostics have been suggested previously (Life Sciences Research Office 1994, Gunter 

1996) and may be required until clinical assays have been standardized. 

Vitamin B6 forms in serum are most commonly measured by high performance liquid 

chromatography (HPLC) with fluorometric detection; chemical derivatization (sample, online, 

or post-column) is almost always used to enhance PLP fluorescence (Rybak 2004). Enzymatic 

(radioactive or nonradioactive) and microbiological methods have also been employed (Coburn 

2000). LC-MS/MS methods are emerging (Midttun 2005). The comparability of methods could 

be improved (Rybak 2005); such improvement is expected to occur in the future due to the new 

availability of NIST SRM 1950 and 3950 (certified concentrations for serum PLP by LC-MS/MS). 

Serum vitamin B12 is commonly measured by competitive protein-binding assay (Carmel 2011). 

Research methods for tHcy determination are HPLC with fluorescence detection or coupled to 

tandem mass spectrometry; clinical methods are based on immunoassay or enzymatic principle 

(Refsum 2004). MMA is measured by gas chromatography coupled to mass spectrometry (GCMS) or by LC-MS/MS (Pedersen 2011). The comparability among methods for serum vitamin 

B12, plasma Hcy, and MMA is superior to that for folate. The following international reference 

materials are available: NIBSC 03/178 for serum vitamin B12 (consensus value); and NIST SRM 

1955 and 1950 for plasma tHcy (certified concentration by LC-MS/MS or GC-MS).

Data in NHANES. Folate and vitamin B12 data presented in this report were generated by 

use of the commercial BioRad Quantaphase II radio-protein-binding assay kit. This is the same 

method used during the first four years of the continuous NHANES survey (1999-2002) and 

during NHANES III (1988-1994) (Yetley 2011). The BioRad assay measures approximately 

35% lower than the traditional microbiologic assay (Life Sciences Research Office 1994). As a 

result, the conventional cutoff values of less than 3 ng/mL for low serum folate concentrations, 

representing a negative folate balance at the time the blood sample was drawn, and less than 

140 ng/mL for low RBC folate concentrations (Life Sciences Research Office 1984) should 

be adjusted to less than 2 ng/mL and less than 95 ng/mL, respectively (Wright 1998). A 2005 

WHO Technical Consultation on folate and vitamin B12 deficiencies estimated blood folate and 

vitamin B12 concentrations below which plasma metabolite concentrations (tHcy for folate and 

MMA for vitamin B12) became elevated. It arrived at the following consensus cutoff values: 4 

ng/mL (10 nmol/L) for serum folate, 151 ng/mL (340 nmol/L) for RBC folate, and 203 pg/mL 

(150 pmol/L) for serum vitamin B12 (de Benoist 2008). Because the folate data used to derive 

these cutoff values were generated with the microbiologic assay, the cutoff values are not directly 

applicable to data generated with the BioRad radio-protein-binding assay. For this report, we used 

cutoff values of 2 ng/mL and 95 ng/mL, respectively, to estimate the prevalence of low serum and 

RBC folate concentrations. To estimate the prevalence of low serum vitamin B12 concentrations, 

we used a cutoff value of 200 pg/mL. This cutoff value is very close to the WHO consensus cutoff 

value and has been widely used in previous studies (Carmel 2011).

Vitamin B6 data presented in this report include serum PLP and 4PA. They were generated by use 

of HPLC with post-column derivatization and fluorometric detection (Rybak 2004; Rybak 2009). 

We used a cutoff value of 20 nmol/L to indicate low serum PLP concentrations. This cutoff value 

was used by the Institute of Medicine as the basis for the Estimated Average Requirement (EAR) 

(1998); it may overestimate the vitamin B6 requirement for health maintenance of more than half 

the group.
18 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

tHcy data presented in this report were generated by use of 

the commercial Abbott fluorescence polarization immunoassay 

kit. MMA data were generated through a GC-MS method. 

Frequently used cutoff values for elevated concentrations of 

plasma tHcy and MMA are 13 μmol/L (Jacques 1999) and 271 

nmol/L (Allen 1990), respectively.

Monitoring the folate status of the U.S. population over time 

has been a priority (Yetley 2011). It has been so first because 

serum and RBC folate results from NHANES II (1976–1980) 

(Senti 1985) and NHANES III (1988–1994) (Wright 1998) 

suggested that the folate status of some population groups might 

be of public health concern; a second reason was to assess the 

impact of folic acid fortification (Pfeiffer 2007). Vitamin B12 

status of the U.S. population has been monitored during the 

second phase of NHANES III (1991–1994) (Wright 1998) 

and during eight years of the continuous survey (1999–2006). 

Plasma metabolite concentrations have also been monitored 

during several years of the continuous survey (tHcy 1999–2006; 

MMA 1999–2004). 

Pfeiffer et al. (2007) showed that the introduction of folic acid 

fortification has substantially increased serum and RBC folate 

concentrations in each age group. Serum vitamin B12 concentrations, however, did not change 

appreciably. Circulating tHcy concentrations from prefortification to postfortification decreased 

by approximately 10% in a national sample of the U.S. population (Pfeiffer 2008).

For more information on B vitamins and related biochemical indicators, see the Institute of 

Medicine’s Dietary Reference Intake reports (Institute of Medicine 1998) and fact sheets from 

the National Institutes of Health (NIH), Office of Dietary Supplements (http://ods.od.nih.gov/

Health_Information/Information_About_Individual_Dietary_Supplements.aspx).

Highlights

Blood concentrations of water-soluble B vitamins (folate, vitamins B6 and B12) in the U.S. 

population showed the following demographic patterns and characteristics:

•	 The highest concentrations were generally found in the youngest age group, except 

for RBC folate and the vitamin B6 catabolite 4-pyridoxic acid where the highest 

concentrations were found in the oldest age group.

•	 No consistent pattern was observed with regard to gender.

•	 A specific race/ethnic pattern was observed: non-Hispanic blacks had the lowest folate 

and the highest vitamin B12 status, non-Hispanic whites had the highest folate and the 

lowest vitamin B12 status, and Mexican Americans had intermediate folate and vitamin 

B12 status.

•	 In the era of folic acid fortification, the prevalence of folate deficiency was very low 

throughout the population.

•	 The likelihood of being vitamin B6 and B12 deficient was higher in persons 40 years 

and older compared to younger persons.
1. Water-Soluble Vitamins 19

Monitoring the continued effect of the U.S. folic acid fortification program of enriched grains 

and cereal products on serum and RBC folate concentrations is of great public health interest. 

Serum folate concentrations more than doubled and RBC folate concentrations increased by 

approximately 50% after the introduction of fortification in 1998. Regardless of gender or race/

ethnicity, we observed small decreases (< 10%) in serum and RBC folate concentrations from the 

earlier (1999–2002) to the later (2003–2006) post-fortification period (Figures H.1.a and H.1.b). 

However, during the first eight years post-fortification covered in this report (1999–2006), the 

prevalence of low serum (< 2 ng/mL) and RBC folate (< 95 ng/mL) concentrations was less than 

1% in the U.S. population, including women of childbearing age, regardless of race/ethnicity 

(data not shown). Folate deficiency was virtually non-existent in the general population, and it 

may be limited to persons with malabsorption, alcohol abusers, or consumers of certain drugs.

a a a a a 

a 

b b 

b 

b 

b 

b 

c c 

c 

c c 

c 

0 

2 

4 

6 

8 

10 

12 

14 

16 

18 

20 

Total 

population 

Males Females Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Serum folate (ng/mL) 

1988-1994 1999-2002 2003-2006 

Figure H.1.a. Age-adjusted geometric mean concentrations of serum 

folate in the U.S. population aged 4 years and older by gender or 

race/ethnicity, National Health and Nutrition Examination Survey, 

1988–2006. 

Error bars represent 95% confidence intervals. Within a demographic group, bars 

not sharing a common letter differ (p < 0.05). Age adjustment was done using 

direct standardization.

a a a a 

a 

a 

b b b 

b 

b 

b 

c c c c 

c 

c 

0 

50 

100 

150 

200 

250 

300 

350 

Total 

population 

Males Females Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Red blood cell folate (ng/mL) 

1988-1994 1999-2002 2003-2006 

Figure H.1.b. Age-adjusted geometric mean concentrations of RBC folate 

in the U.S. population aged 4 years and older by gender or race/ethnicity, 

National Health and Nutrition Examination Survey, 1988–2006. 

Error bars represent 95% confidence intervals. Within a demographic group, bars 

not sharing a common letter differ (p < 0.05). Age-adjustment was done using 

direct standardization.

Because of the close relationship of folate and vitamin B12 in one-carbon metabolism, it is of 

interest to see whether serum vitamin B12 concentrations changed since the introduction of folic 

acid fortification and whether there are differences among race/ethnic groups. We observed a small 

increase in serum vitamin B12 concentrations from pre- (1991–1994) to post-fortification (1999–

2002). We then found similar concentrations during 2003–2006 for the total population and for 

males and females (Figure H.1.c). The increase from pre- to post-fortification was observed for 

non-Hispanic whites, but not for non-Hispanic blacks and Mexican Americans; the latter two 

groups had higher serum vitamin B12 concentrations than non-Hispanic whites during both preand post-fortification. 

Assessing the extent of inadequate vitamin B12 status in the older U.S. population is challenging 

because serum vitamin B12 is not sensitive enough, plasma tHcy is not specific, and both plasma 

MMA and tHcy are artificially elevated when renal function is impaired, which is common in older 

persons. As expected, we found a higher prevalence of elevated plasma MMA (17%) or tHcy (19%) 

concentrations, potentially indicating suboptimal vitamin B12 status, than we found in the prevalence 

of low serum vitamin B12 concentrations (4%) in older persons (Figure H.1.d). Defining better 

cutoff values for vitamin B12 status biomarkers remains a continued area of research (Bailey 2011).
20 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

a a a a a 

a b b b a a 

b b b b a a 

b 

0 

100 

200 

300 

400 

500 

600 

Total 

population 

Males Females Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Serum vitamin B12 (pg/mL) 

1991-1994 1999-2002 2003-2006 

Figure H.1.c. Age-adjusted geometric mean concentrations of serum 

vitamin B12 in the U.S. population aged 4 years and older by gender 

or race/ethnicity, National Health and Nutrition Examination Survey, 

1991–2006. 

Error bars represent 95% confidence intervals. Within a demographic group, bars 

not sharing a common letter differ (p < 0.05). Age adjustment was done using 

direct standardization. 

0 

5 

10 

15 

20 

25 

Serum B12 

< 200 pg/mL 

Plasma MMA 

> 271 nmol/L Plasma tHcy  > 13 mol/L 

Prevalence (%) 

Figure H.1.d. Prevalence estimates of low serum vitamin B12 (B12), 

high plasma methylmalonic acid (MMA), and high plasma total 

homocysteine (tHcy) concentrations in U.S. persons 60 years and older, 

National Health and Nutrition Examination Survey, 2003–2006. 

Data shown for plasma MMA are from NHANES 2003–2004 only. Error bars 

represent 95% confidence intervals.

Detailed Observations

The selected observations mentioned below are derived from the tables and figures presented next. 

Statements about categorical differences between demographic groups noted below are based on 

non-overlapping confidence limits from univariate analysis without adjusting for demographic 

variables (e.g., age, gender, race/ethnicity) or other blood concentration determinants (e.g., dietary 

intake, supplement usage, smoking, BMI). A multivariate analysis may alter the size and statistical 

significance of these categorical differences. Furthermore, additional significant differences of 

smaller magnitude may be present despite their lack of mention here (e.g., if confidence limits 

slightly overlap or if differences are not statistically significant before covariate adjustment has 

occurred). For a selection of citations of descriptive NHANES papers related to these biochemical 

indicators of diet and nutrition, see Appendix G.

Geometric mean concentrations (NHANES 2003–2006):

•	 Serum and RBC folate concentrations followed a U-shaped age pattern, with the lowest 

concentrations seen in adolescents and young adults, respectively (Tables 1.1.a.1 and 

1.2.a.1; Figures 1.1.a and 1.2.a).

•	 Serum PLP concentrations declined from childhood to adolescence, then stabilized 

in older age groups (Table 1.3.a.1 and Figure 1.3.a). Serum 4PA concentrations were 

lowest in adolescence and increased steadily through the oldest age group (Table 1.4.a.1 

and Figure 1.4.a).

•	 Serum vitamin B12 concentrations declined from childhood to adolescence and then 

stabilized in older age groups (Table 1.5.a.1), while plasma MMA concentrations were 

relatively stable through young adulthood, and then increased with age (Table 1.7.a.1 

and Figure 1.7.a).

•	 Plasma tHcy concentrations in adults increased with age (Table 1.6.a.1 and Figure 1.6.a).

•	 Females had higher serum and RBC folate concentrations than males (Tables 1.1.a.1 

and 1.2.a.1); males had higher serum PLP and plasma tHcy concentrations than females 

(Tables 1.3.a.1 and 1.6.a.1); males and females had similar serum 4PA (Table 1.4.a.1), 
1. Water-Soluble Vitamins 21

vitamin B12 (Table 1.5.a.1) and plasma MMA (Table 1.7.a.1) concentrations.

•	 Non-Hispanic whites had the highest concentrations of serum and RBC folate (Tables 

1.1.a.1 and 1.2.a.1), serum 4PA (Table 1.4.a.1), and plasma MMA (Table 1.7.a.1). 

They also had the lowest concentrations of serum vitamin B12 (Table 1.5.a.1). NonHispanic blacks had the lowest concentrations of RBC folate (Table 1.2.a.1) and serum 

PLP (Table 1.3.a.1). Mexican Americans had the lowest concentrations of plasma tHcy 

(Table 1.6.a.1).

Changes in geometric mean concentrations across survey cycles:

•	 Serum folate concentrations decreased slightly (< 10%) between the 1999–2000 and 

2001–2002 survey cycles; however, concentrations stabilized over the next two survey 

cycles (Table 1.1.b). 

•	 RBC folate concentrations were similar across all survey cycles except for a < 10% 

decrease between the 2001–2002 and 2003–2004 survey cycles (Table 1.2.b). 

•	 We observed no changes in serum vitamin B12 (Table 1.5.b), plasma tHcy (Table 

1.6.b), or plasma MMA (Table 1.7.b) concentrations over time.

Prevalence estimates of low or high biochemical indicator concentrations:

•	 In 2003–2006, less than 1% of the population aged 1 year and older had RBC folate 

concentrations < 95 ng/mL (Table 1.2.c). Similarly, less than 1% of the population had 

low serum folate concentrations < 2 ng/mL; however, the estimates had large variances 

and we do not present a prevalence table for this indicator. 

•	 Of the population aged 1 year and older, approximately 11% had serum PLP 

concentrations < 20 nmol/L in 2005–2006 (Table 1.3.c). Compared to the prevalence 

of low PLP concentrations in persons 20–39 years of age, the prevalence of low PLP 

concentrations was lower in all younger age groups and higher in all older age groups.

•	 Approximately 2% of the population aged 1 year and older and 4% of persons 60 years and 

older had serum vitamin B12 concentrations < 200 pg/mL in 2003-2006 (Table 1.5.c). 

•	 We found elevated plasma tHcy concentrations (> 13 μmol/L) in 2003–2006 in 

approximately 8% of the population aged 20 years and older and in 19% of persons 60 

years and older (Table 1.6.c).

•	 Approximately 7% of the population aged 3 years and older and 17% of persons 60 years 

and older had plasma MMA concentrations > 271 nmol/L in 2003-2004 (Table 1.7.c).

•	 Between 1999 and 2006 (2004 for MMA), we did not observe any change in the 

prevalence of low RBC folate (Table 1.2.d), low serum vitamin B12 (Table 1.5.d), high 

plasma tHcy (Table 1.6.d), and high plasma MMA (Table 1.7.d) concentrations.
22

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.1.a.1. Serum folate: Concentrations

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for the total U.S. population aged 1 year and older,National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 1 year and older 12.3 (12.0 – 12.6) 4.51 (4.36 – 4.61) 5.46 (5.26 – 5.66) 12.2 (11.9 – 12.5) 28.5 (27.5 – 29.5) 34.0 (32.5 – 36.0) 16,411Age group1–5 years 16.2 (15.5 – 16.9) 6.29 (5.51 – 6.93) 7.61 (6.92 – 8.24) 16.0 (15.5 – 16.5) 36.0 (32.0 – 41.9) 50.8 (37.7 – 77.7) 1,690

6–11 years 16.1 (15.6 – 16.6) 8.21 (7.82 – 8.58) 9.04 (8.63 – 9.58) 15.7 (15.3 – 16.2) 29.9 (27.5 – 35.0) 35.9 (32.3 – 46.3) 1,749

12–19 years 11.2 (11.0 – 11.5) 4.86 (4.57 – 5.11) 5.62 (5.45 – 5.83) 11.3 (10.9 – 11.6) 20.9 (19.9 – 21.8) 24.6 (23.4 – 25.8) 4,028

20–39 years 10.4 (10.1 – 10.7) 4.24 (4.08 – 4.46) 4.93 (4.75 – 5.09) 10.5 (10.1 – 10.9) 20.5 (19.5 – 22.9) 26.1 (23.1 – 29.9) 3,242

40–59 years 11.6 (11.2 – 12.0) 4.23 (3.70 – 4.40) 5.09 (4.57 – 5.42) 11.6 (11.3 – 11.9) 25.2 (24.1 – 28.1) 32.8 (29.2 – 37.1) 2,649

60 years and older 15.6 (15.0 – 16.1) 5.31 (4.83 – 5.57) 6.32 (5.95 – 6.61) 15.8 (15.2 – 16.3) 35.7 (34.2 – 37.7) 45.7 (42.1 – 49.6) 3,053

GenderMales 11.7 (11.4 – 12.0) 4.39 (4.29 – 4.60) 5.32 (5.00 – 5.55) 11.6 (11.3 – 11.9) 26.4 (25.6 – 27.8) 32.2 (30.6 – 34.8) 8,050

Females 12.9 (12.5 – 13.3) 4.56 (4.41 – 4.81) 5.61 (5.33 – 5.91) 12.9 (12.5 – 13.2) 29.7 (28.8 – 31.2) 35.6 (33.6 – 37.8) 8,361

Race/ethnicityMexican Americans 11.1 (10.7 – 11.4) 4.67 (4.52 – 4.92) 5.49 (5.17 – 5.68) 11.1 (10.8 – 11.4) 22.2 (20.8 – 23.4) 25.9 (24.3 – 28.8) 4,212

Non-Hispanic Blacks 10.4 (10.1 – 10.7) 4.19 (4.01 – 4.36) 4.83 (4.56 – 5.07) 10.3 (9.94 – 10.8) 22.6 (21.4 – 23.5) 27.0 (25.6 – 29.3) 4,297

Non-Hispanic Whites 13.0 (12.5 – 13.4) 4.58 (4.40 – 4.81) 5.72 (5.36 – 5.98) 12.9 (12.5 – 13.3) 30.1 (29.2 – 31.5) 36.0 (34.2 – 38.5) 6,633
1−5 6−11 12−19 20−39 40−59 60+ 1−5 6−11 12−19 20−39 40−59 60+ 

1−5 6−11 12−19 20−39 40−59 60+ 

0 5 10 15 20 

Serum folate

(ng/mL) 

Overall 

1−5 6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

20 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 1.1.a. Serum folate: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Serum folate (ng/mL) 0 5 10 15 

Females Males 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

1−5 6−11 

Age (years) 

12−19 20−39 40−59 60+ 1−5 6−11 

Age (years) 

12−19 20−39 40−59 60+ 

Serum folate

(ng/mL) 

0 5 10 15 20 

1. Water -Soluble Vitamins 23
24 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.1.a.2. Serum folate: Total population

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for the total U.S. population aged

1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 12.3 (12.0 – 12.6) 5.46 (5.26 – 5.66) 12.2 (11.9 – 12.5) 28.5 (27.5 – 29.5) 16,411

1–5 years 16.2 (15.5 – 16.9) 7.61 (6.92 – 8.24) 16.0 (15.5 – 16.5) 36.0 (32.0 – 41.9) 1,690

6–11 years 16.1 (15.6 – 16.6) 9.04 (8.63 – 9.58) 15.7 (15.3 – 16.2) 29.9 (27.5 – 35.0) 1,749

12–19 years 11.2 (11.0 – 11.5) 5.62 (5.45 – 5.83) 11.3 (10.9 – 11.6) 20.9 (19.9 – 21.8) 4,028

20–39 years 10.4 (10.1 – 10.7) 4.93 (4.75 – 5.09) 10.5 (10.1 – 10.9) 20.5 (19.5 – 22.9) 3,242

40–59 years 11.6 (11.2 – 12.0) 5.09 (4.57 – 5.42) 11.6 (11.3 – 11.9) 25.2 (24.1 – 28.1) 2,649

60 years and older 15.6 (15.0 – 16.1) 6.32 (5.95 – 6.61) 15.8 (15.2 – 16.3) 35.7 (34.2 – 37.7) 3,053

Males

Total, 1 year and older 11.7 (11.4 – 12.0) 5.32 (5.00 – 5.55) 11.6 (11.3 – 11.9) 26.4 (25.6 – 27.8) 8,050

1–5 years 16.2 (15.3 – 17.1) 7.56 (6.40 – 8.53) 15.8 (15.2 – 16.3) 36.2 (32.0 – 46.5) 854

6–11 years 15.8 (15.2 – 16.4) 9.10 (8.37 – 9.77) 15.3 (14.8 – 16.0) 29.1 (26.2 – 34.9) 854

12–19 years 11.2 (10.9 – 11.5) 5.45 (4.94 – 5.82) 11.3 (10.9 – 11.6) 20.5 (19.8 – 21.9) 2,041

20–39 years 9.83 (9.51 – 10.2) 4.84 (4.66 – 5.03) 9.89 (9.53 – 10.3) 18.3 (17.6 – 20.0) 1,462

40–59 years 10.8 (10.4 – 11.3) 4.84 (4.39 – 5.26) 11.0 (10.4 – 11.4) 22.7 (20.5 – 25.8) 1,305

60 years and older 14.7 (14.0 – 15.6) 6.12 (5.81 – 6.42) 14.7 (13.7 – 15.7) 34.9 (32.5 – 41.9) 1,534

Females

Total, 1 year and older 12.9 (12.5 – 13.3) 5.61 (5.33 – 5.91) 12.9 (12.5 – 13.2) 29.7 (28.8 – 31.2) 8,361

1–5 years 16.3 (15.6 – 17.0) 7.65 (6.80 – 8.30) 16.3 (15.8 – 17.0) 34.6 (30.2 – 46.5) 836

6–11 years 16.5 (15.8 – 17.2) 9.01 (8.62 – 9.59) 16.2 (15.5 – 16.9) 30.8 (28.2 – 36.6) 895

12–19 years 11.3 (10.9 – 11.7) 5.76 (5.57 – 6.04) 11.2 (10.9 – 11.7) 21.3 (19.6 – 23.4) 1,987

20–39 years 11.0 (10.6 – 11.5) 5.05 (4.63 – 5.27) 11.1 (10.7 – 11.6) 23.1 (21.1 – 26.1) 1,780

40–59 years 12.3 (11.9 – 12.8) 5.37 (4.56 – 5.96) 12.4 (11.9 – 12.9) 27.6 (25.2 – 32.1) 1,344

60 years and older 16.2 (15.7 – 16.8) 6.57 (6.05 – 6.92) 16.5 (15.9 – 17.2) 36.1 (34.4 – 38.5) 1,519

Table 1.1.a.3. Serum folate: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for Mexican Americans in the U.S.

population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 11.1 (10.7 – 11.4) 5.49 (5.17 – 5.68) 11.1 (10.8 – 11.4) 22.2 (20.8 – 23.4) 4,212

1–5 years 14.1 (13.4 – 14.7) 7.56 (6.85 – 8.17) 14.0 (13.3 – 14.8) 26.2 (23.8 – 29.4) 542

6–11 years 15.4 (14.7 – 16.2) 9.03 (8.32 – 9.67) 15.2 (14.2 – 16.0) 28.2 (26.2 – 32.2) 586

12–19 years 10.9 (10.6 – 11.2) 5.89 (5.43 – 6.28) 11.1 (10.8 – 11.5) 19.1 (18.2 – 19.8) 1,281

20–39 years 9.60 (9.24 – 9.96) 5.04 (4.70 – 5.19) 9.62 (9.07 – 10.2) 18.1 (16.8 – 19.6) 781

40–59 years 10.4 (9.76 – 11.1) 5.13 (4.59 – 5.67) 10.1 (9.51 – 11.0) 21.0 (18.7 – 23.7) 469

60 years and older 12.4 (11.6 – 13.2) 5.36 (4.61 – 6.41) 12.1 (11.6 – 12.6) 27.1 (24.6 – 37.1) 553

Males

Total, 1 year and older 10.6 (10.3 – 11.0) 5.35 (4.99 – 5.65) 10.7 (10.3 – 11.0) 20.2 (19.5 – 22.4) 2,042

1–5 years 13.7 (13.1 – 14.5) 8.03 (6.22 – 8.33) 13.5 (12.7 – 14.5) 23.9 (21.2 – 31.4) 263

6–11 years 15.1 (14.3 – 16.0) 8.68 (7.46 – 9.86) 14.9 (13.7 – 16.0) 28.3 (25.4 – 32.3) 285

12–19 years 10.9 (10.5 – 11.3) 5.62 (4.99 – 5.94) 11.1 (10.6 – 11.4) 19.1 (17.7 – 20.6) 638

20–39 years 9.11 (8.67 – 9.57) 4.90 (4.47 – 5.37) 9.09 (8.68 – 9.70) 15.6 (14.7 – 18.7) 347

40–59 years 10.1 (9.43 – 10.8) 5.11 (4.48 – 5.91) 10.0 (9.19 – 10.7) 19.1 (18.1 – 22.5) 237

60 years and older 11.4 (10.7 – 12.1) 5.27 (4.61 – 6.23) 10.5 (9.85 – 12.1) 26.0 (22.9 – 36.9) 272

Females

Total, 1 year and older 11.5 (11.1 – 12.0) 5.64 (5.15 – 5.87) 11.6 (11.3 – 11.8) 23.3 (21.8 – 25.6) 2,170

1–5 years 14.4 (13.6 – 15.2) 7.34 (6.41 – 8.10) 14.4 (13.7 – 15.9) 26.5 (24.5 – 31.9) 279

6–11 years 15.7 (14.9 – 16.5) 9.13 (8.01 – 10.2) 15.5 (14.8 – 16.3) 27.8 (25.9 – 34.2) 301

12–19 years 11.0 (10.7 – 11.3) 6.23 (5.78 – 6.54) 11.2 (10.8 – 11.6) 19.0 (18.2 – 21.0) 643

20–39 years 10.2 (9.62 – 10.8) 5.11 (4.74 – 5.38) 10.4 (9.53 – 11.0) 19.3 (18.1 – 21.8) 434

40–59 years 10.7 (10.0 – 11.5) 5.16 (3.80 – 5.85) 10.4 (9.57 – 11.4) 22.4 (19.1 – 40.0) 232

60 years and older 13.3 (12.0 – 14.7) 5.62 (4.00 – 6.65) 13.0 (12.1 – 13.7) 29.7 (25.3 – 64.8) 281
1. Water-Soluble Vitamins 25

Table 1.1.a.4. Serum folate: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for non-Hispanic blacks in the 

U.S.population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 10.4 (10.1 – 10.7) 4.83 (4.56 – 5.07) 10.3 (9.94 – 10.8) 22.6 (21.4 – 23.5) 4,297

1–5 years 15.0 (14.0 – 16.0) 7.08 (5.99 – 7.80) 14.9 (14.3 – 15.6) 32.9 (28.0 – 40.7) 481

6–11 years 14.8 (14.2 – 15.3) 8.62 (7.91 – 9.03) 14.6 (14.0 – 15.2) 25.3 (23.9 – 29.4) 554

12–19 years 9.98 (9.63 – 10.4) 5.19 (4.98 – 5.39) 9.91 (9.59 – 10.3) 18.3 (17.7 – 19.1) 1,417

20–39 years 8.92 (8.56 – 9.29) 4.56 (4.26 – 4.81) 8.73 (8.34 – 9.23) 17.7 (16.7 – 19.1) 711

40–59 years 9.81 (9.28 – 10.4) 4.34 (3.93 – 4.99) 9.75 (9.04 – 10.3) 20.0 (18.8 – 26.0) 621

60 years and older 11.5 (10.8 – 12.3) 4.88 (4.48 – 5.29) 11.3 (10.7 – 11.9) 27.2 (24.5 – 36.0) 513

Males

Total, 1 year and older 10.1 (9.84 – 10.4) 4.67 (4.34 – 4.94) 10.1 (9.76 – 10.5) 21.1 (19.7 – 23.2) 2,141

1–5 years 14.9 (13.7 – 16.2) 6.69 (5.91 – 7.81) 14.7 (13.9 – 15.5) 36.5 (29.0 – 51.9) 238

6–11 years 14.4 (13.8 – 15.1) 8.87 (8.20 – 9.55) 14.3 (13.6 – 14.9) 24.3 (21.2 – 30.8) 273

12–19 years 10.2 (9.85 – 10.6) 5.02 (4.75 – 5.19) 10.3 (9.82 – 10.8) 19.0 (17.9 – 19.8) 742

20–39 years 8.48 (8.07 – 8.91) 4.33 (4.01 – 4.81) 8.35 (7.82 – 8.89) 15.4 (14.5 – 17.7) 339

40–59 years 9.41 (8.82 – 10.0) 4.11 (3.42 – 4.99) 9.38 (8.49 – 10.1) 18.7 (17.3 – 32.9) 291

60 years and older 11.1 (10.4 – 11.8) 4.73 (3.87 – 5.82) 10.7 (9.77 – 11.3) 29.0 (23.9 – 32.7) 258

Females

Total, 1 year and older 10.6 (10.2 – 11.0) 5.00 (4.62 – 5.23) 10.5 (10.0 – 11.1) 23.3 (22.0 – 24.9) 2,156

1–5 years 15.1 (14.0 – 16.4) 7.33 (5.00 – 8.42) 15.1 (14.2 – 16.3) 28.8 (26.7 – 40.8) 243

6–11 years 15.1 (14.1 – 16.1) 8.03 (7.24 – 8.98) 14.9 (14.0 – 15.9) 26.0 (24.3 – 33.6) 281

12–19 years 9.76 (9.35 – 10.2) 5.42 (4.98 – 5.57) 9.67 (9.21 – 10.0) 17.7 (16.9 – 18.4) 675

20–39 years 9.30 (8.78 – 9.86) 4.68 (4.44 – 5.01) 9.00 (8.52 – 9.59) 19.1 (17.8 – 20.8) 372

40–59 years 10.2 (9.56 – 10.8) 4.48 (4.07 – 5.18) 10.1 (9.24 – 10.7) 22.1 (19.2 – 27.7) 330

60 years and older 11.8 (10.8 – 12.9) 4.95 (4.26 – 5.65) 11.6 (11.0 – 12.8) 26.8 (23.9 – 45.8) 255

Table 1.1.a.5. Serum folate: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for non-Hispanic whites in the 

U.S.population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 13.0 (12.5 – 13.4) 5.72 (5.36 – 5.98) 12.9 (12.5 – 13.3) 30.1 (29.2 – 31.5) 6,633

1–5 years 17.4 (16.2 – 18.6) 7.94 (6.77 – 8.99) 17.0 (16.0 – 17.8) 37.9 (34.7 – 56.0) 478

6–11 years 16.8 (16.1 – 17.5) 9.54 (8.59 – 10.0) 16.5 (15.9 – 17.2) 31.7 (28.0 – 37.6) 449

12–19 years 11.7 (11.3 – 12.1) 5.83 (5.57 – 6.19) 11.6 (11.3 – 12.2) 22.1 (21.2 – 23.4) 1,048

20–39 years 11.0 (10.6 – 11.5) 5.22 (4.82 – 5.54) 11.1 (10.7 – 11.5) 22.9 (20.6 – 26.2) 1,453

40–59 years 12.0 (11.5 – 12.6) 5.14 (4.55 – 5.61) 12.1 (11.7 – 12.6) 26.1 (24.3 – 31.7) 1,357

60 years and older 16.3 (15.7 – 17.0) 6.55 (6.19 – 6.92) 16.7 (16.1 – 17.2) 36.8 (34.9 – 39.4) 1,848

Males

Total, 1 year and older 12.3 (11.8 – 12.7) 5.56 (5.04 – 5.93) 12.1 (11.7 – 12.6) 28.0 (26.4 – 29.8) 3,268

1–5 years 17.3 (16.0 – 18.8) 8.02 (5.84 – 9.82) 16.5 (15.7 – 17.9) 36.3 (32.6 – 55.8) 259

6–11 years 16.4 (15.5 – 17.5) 8.91† (7.81 – 10.0) 16.2 (15.1 – 16.9) 30.4† (26.1 – 52.6) 216

12–19 years 11.6 (11.2 – 12.0) 5.58 (4.93 – 6.17) 11.6 (11.2 – 12.1) 21.8 (20.4 – 23.3) 528

20–39 years 10.4 (9.94 – 10.9) 5.30 (4.75 – 5.82) 10.5 (9.93 – 11.0) 19.5 (18.1 – 22.9) 638

40–59 years 11.2 (10.6 – 11.9) 4.95 (4.36 – 5.35) 11.5 (10.9 – 12.1) 22.9 (20.9 – 26.8) 689

60 years and older 15.5 (14.5 – 16.5) 6.35 (5.91 – 6.72) 15.6 (14.5 – 16.6) 37.0 (32.7 – 45.3) 938

Females

Total, 1 year and older 13.7 (13.2 – 14.1) 5.88 (5.45 – 6.20) 13.7 (13.2 – 14.2) 31.6 (30.3 – 32.9) 3,365

1–5 years 17.4 (16.0 – 18.9) 7.79† (6.32 – 8.79) 17.1 (15.9 – 18.0) 42.7† (30.9 – 73.2) 219

6–11 years 17.2 (16.4 – 18.1) 9.71 (8.72 – 10.2) 17.0 (15.9 – 17.7) 31.7 (28.3 – 38.2) 233

12–19 years 11.8 (11.3 – 12.4) 5.90 (5.64 – 6.67) 11.8 (11.1 – 12.5) 22.2 (20.5 – 25.1) 520

20–39 years 11.7 (11.1 – 12.4) 5.19 (4.54 – 5.60) 11.8 (11.1 – 12.5) 25.7 (22.8 – 30.7) 815

40–59 years 12.9 (12.3 – 13.5) 5.40 (4.54 – 6.22) 13.1 (12.3 – 13.7) 30.9 (25.5 – 34.0) 668

60 years and older 17.1 (16.5 – 17.7) 6.85 (6.21 – 7.22) 17.6 (16.8 – 18.4) 36.6 (34.9 – 39.7) 910

† Estimate is subject to greater uncertainty due to small cell size.
26 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.1.b. Serum folate: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 3 years and older

 1999–2000 14.0 (13.4 – 14.8) 5.74 (5.35 – 6.10) 14.2 (13.4 – 15.0) 33.1 (31.6 – 34.9) 7,526

 2001–2002 12.9 (12.5 – 13.3) 5.73 (5.36 – 6.05) 13.0 (12.7 – 13.4) 27.2 (26.4 – 28.5) 8,386

 2003–2004 12.1 (11.7 – 12.6) 5.40 (5.12 – 5.69) 11.9 (11.5 – 12.4) 28.2 (27.1 – 29.7) 7,836

 2005–2006 12.4 (11.9 – 12.9) 5.47 (5.10 – 5.80) 12.3 (11.9 – 12.7) 28.5 (26.5 – 30.2) 7,774

Age group

3-5 years

 1999–2000 20.1 (18.8 – 21.4) 10.5 (7.89 – 12.2) 19.1 (17.9 – 21.6) 38.2 (34.0 – 45.1) 361

 2001–2002 17.3 (16.3 – 18.4) 9.44 (7.08 – 10.6) 17.1 (16.1 – 18.3) 31.9 (29.5 – 38.5) 438

 2003–2004 16.6 (15.1 – 18.2) 8.59 (5.22 – 9.61) 16.2 (15.2 – 17.0) 34.5 (29.4 – 57.9) 448

 2005–2006 17.6 (16.5 – 18.8) 9.56 (8.34 – 10.3) 16.7 (16.1 – 17.9) 37.6 (31.3 – 77.2) 441

6–11 years

 1999–2000 19.3 (18.4 – 20.3) 11.0 (10.6 – 11.4) 19.3 (18.4 – 19.9) 33.4 (31.6 – 36.3) 885

 2001–2002 17.2 (16.6 – 17.9) 9.31 (8.75 – 9.78) 17.1 (16.3 – 17.8) 32.7 (29.9 – 37.9) 1,023

 2003–2004 15.6 (14.9 – 16.3) 9.39 (8.66 – 9.85) 15.2 (14.7 – 16.0) 27.4 (24.4 – 34.0) 843

 2005–2006 16.7 (15.9 – 17.5) 8.77 (8.26 – 9.60) 16.3 (15.5 – 17.1) 32.4 (29.5 – 36.9) 906

12–19 years

 1999–2000 13.3 (12.6 – 14.0) 6.26 (5.72 – 6.61) 13.3 (12.7 – 14.0) 27.6 (25.6 – 31.3) 2,124

 2001–2002 12.2 (11.6 – 12.8) 5.91 (5.29 – 6.28) 12.5 (11.9 – 13.3) 22.1 (21.2 – 23.4) 2,208

 2003–2004 11.0 (10.5 – 11.5) 5.56 (5.20 – 6.02) 11.0 (10.5 – 11.4) 19.7 (19.1 – 22.1) 2,058

 2005–2006 11.5 (11.2 – 11.8) 5.65 (5.39 – 5.90) 11.6 (11.1 – 12.1) 21.8 (21.1 – 22.6) 1,970

20–39 years

 1999–2000 11.8 (11.0 – 12.7) 5.15 (4.40 – 5.55) 11.6 (10.6 – 12.8) 28.6 (25.6 – 30.8) 1,470

 2001–2002 11.1 (10.6 – 11.6) 5.27 (4.78 – 5.59) 11.1 (10.6 – 11.6) 22.6 (20.6 – 24.3) 1,714

 2003–2004 10.2 (9.78 – 10.6) 4.83 (4.62 – 5.01) 10.2 (9.59 – 10.8) 20.0 (19.1 – 22.9) 1,555

 2005–2006 10.6 (10.2 – 11.1) 5.07 (4.76 – 5.33) 10.8 (10.3 – 11.2) 21.1 (19.2 – 25.9) 1,687

40–59 years

 1999–2000 13.6 (12.7 – 14.5) 5.37 (4.37 – 6.08) 13.6 (12.7 – 14.7) 31.6 (30.0 – 35.4) 1,199

 2001–2002 12.2 (11.7 – 12.7) 5.63 (4.86 – 6.06) 12.5 (11.9 – 13.1) 24.0 (22.4 – 25.3) 1,475

 2003–2004 11.6 (11.0 – 12.3) 5.20 (4.57 – 5.60) 11.6 (11.1 – 11.9) 26.0 (23.8 – 32.8) 1,276

 2005–2006 11.6 (11.0 – 12.2) 4.85 (4.39 – 5.57) 11.7 (11.1 – 12.1) 24.4 (22.8 – 29.0) 1,373

60 years and older

 1999–2000 17.4 (16.7 – 18.1) 7.09 (6.48 – 7.51) 17.4 (16.5 – 18.2) 42.3 (39.2 – 44.8) 1,487

 2001–2002 16.1 (15.4 – 16.8) 6.50 (5.75 – 7.09) 16.6 (15.4 – 17.5) 37.3 (34.2 – 40.7) 1,528

 2003–2004 15.7 (15.1 – 16.4) 6.53 (6.13 – 7.00) 15.6 (14.8 – 16.4) 34.9 (32.9 – 37.7) 1,656

 2005–2006 15.4 (14.5 – 16.4) 6.06 (5.40 – 6.58) 15.8 (15.0 – 16.8) 36.4 (34.4 – 41.9) 1,397

Gender

Males

 1999–2000 13.3 (12.7 – 14.0) 5.53 (4.73 – 6.13) 13.4 (12.7 – 14.2) 30.6 (29.0 – 32.2) 3,684

 2001–2002 12.3 (11.8 – 12.8) 5.64 (5.17 – 6.00) 12.5 (12.1 – 13.0) 25.0 (23.7 – 27.0) 4,063

 2003–2004 11.6 (11.1 – 12.1) 5.31 (4.93 – 5.69) 11.5 (11.1 – 11.9) 26.2 (24.7 – 28.1) 3,871

 2005–2006 11.7 (11.2 – 12.1) 5.24 (4.74 – 5.59) 11.6 (11.2 – 12.0) 26.2 (25.2 – 28.5) 3,780

Females

 1999–2000 14.8 (14.0 – 15.6) 5.94 (5.60 – 6.18) 14.8 (14.1 – 16.0) 35.3 (33.7 – 37.5) 3,842

 2001–2002 13.5 (13.1 – 13.9) 5.80 (5.39 – 6.35) 13.6 (13.2 – 14.0) 29.3 (27.3 – 31.6) 4,323

 2003–2004 12.6 (12.1 – 13.1) 5.51 (5.12 – 5.84) 12.5 (12.0 – 13.0) 29.5 (28.3 – 31.6) 3,965

 2005–2006 13.1 (12.5 – 13.7) 5.66 (5.25 – 6.14) 13.2 (12.6 – 13.8) 29.9 (28.2 – 32.2) 3,994

Race/ethnicity

Mexican Americans

 1999–2000 13.2 (12.8 – 13.7) 6.10 (5.49 – 6.51) 13.5 (12.9 – 14.0) 28.4 (27.1 – 30.2) 2,571

 2001–2002 11.6 (10.9 – 12.4) 5.48 (4.66 – 6.08) 11.8 (11.1 – 12.5) 22.5 (20.0 – 26.1) 2,124

 2003–2004 10.9 (10.4 – 11.5) 5.20 (5.09 – 5.50) 11.1 (10.7 – 11.6) 20.9 (19.2 – 23.4) 1,919

 2005–2006 11.1 (10.7 – 11.5) 5.56 (5.18 – 5.79) 11.0 (10.6 – 11.5) 23.1 (21.6 – 25.0) 2,012

Non-Hispanic Blacks

 1999–2000 11.7 (11.1 – 12.4) 5.15 (4.67 – 5.42) 11.6 (10.9 – 12.4) 27.3 (24.9 – 31.5) 1,712

 2001–2002 10.9 (10.2 – 11.6) 5.06 (4.47 – 5.39) 10.7 (10.1 – 11.4) 23.6 (21.7 – 25.2) 2,004

 2003–2004 10.1 (9.66 – 10.6) 4.65 (4.28 – 5.11) 10.1 (9.37 – 10.8) 21.9 (19.9 – 23.7) 2,057

 2005–2006 10.6 (10.1 – 11.1) 4.95 (4.68 – 5.15) 10.5 (9.92 – 11.2) 22.9 (21.4 – 24.0) 2,040

Non-Hispanic Whites

 1999–2000 14.8 (13.8 – 15.8) 6.11 (5.52 – 6.55) 15.0 (13.9 – 16.2) 34.2 (32.6 – 36.0) 2,557

 2001–2002 13.4 (13.0 – 13.9) 5.90 (5.62 – 6.21) 13.6 (13.2 – 14.1) 28.4 (27.2 – 29.9) 3,590

 2003–2004 12.9 (12.2 – 13.5) 5.76 (5.31 – 6.08) 12.7 (12.1 – 13.3) 30.0 (28.5 – 32.1) 3,272

 2005–2006 13.0 (12.4 – 13.6) 5.62 (4.96 – 6.04) 12.9 (12.4 – 13.5) 29.9 (28.3 – 32.2) 3,120
5th Percentile 50th Percentile 95th Percentile

40 

20 

0 

25 

20 

15 

10 

5 

14 

12 

10 

8 

6 

4 

80 

60 

1 

1 1 1 

1 

1 1 

1 

1 1 

1 

1 

1 

1 1 1 

1 

1 1 1 1 

1 1 1 

1 

1 1 1 1 

1 1 1 

1 

1 1 1 

1 

1 1 1 

1 

1 

1 1 

1 

1 

1 1 

1 

1 

1 

1 

1 

1 

1 1 

1 

1 

1 1 

1 

1 

1 1 

1 

1 

1 1 1 

1 1 1 1 

1 1 1 

1 

1 

1 1 

1 1 1 1 

1 

1 

1 

1 

1 

1 1 

1 

1 1 1 1 1 1 1 1 1 1 1 1 

1 1 1 1 

1 

1 1 1 

1 1 

1 1 

1 1 1 1 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(3+y) 

Figure 1.1.b. Serum folate: Concentrations by survey cycle 

Selected percentiles in ng/mL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006 

1. Water -Soluble Vitamins 27
28

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.2.a.1. Red blood cell folate: Concentrations

Geometric mean and selected percentiles of red blood cell concentrations (in ng/mL) for the total U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 1 year and older 265 (261 – 270) 133 (129 – 136) 149 (146 – 152) 261 (256 – 265) 501 (487 – 515) 581 (566 – 604) 16,670Age group1–5 years 272 (265 – 279) 152 (149 – 160) 174 (169 – 178) 266 (261 – 272) 483 (436 – 531) 560 (521 – 668) 1,861

6–11 years 263 (258 – 268) 164 (152 – 171) 180 (172 – 184) 259 (254 – 264) 430 (400 – 456) 470 (457 – 511) 1,779

12–19 years 229 (225 – 234) 126 (123 – 130) 140 (134 – 146) 229 (224 – 233) 370 (355 – 390) 436 (398 – 471) 4,050

20–39 years 244 (238 – 250) 126 (119 – 131) 140 (136 – 144) 241 (235 – 247) 449 (421 – 480) 512 (483 – 547) 3,262

40–59 years 270 (264 – 276) 132 (126 – 137) 149 (143 – 154) 273 (266 – 279) 481 (461 – 510) 554 (519 – 605) 2,649

60 years and older 324 (317 – 332) 147 (140 – 151) 161 (157 – 166) 327 (315 – 338) 656 (622 – 705) 768 (724 – 860) 3,069

GenderMales 259 (253 – 264) 133 (128 – 138) 149 (144 – 153) 255 (250 – 259) 469 (453 – 489) 551 (529 – 588) 8,172

Females 272 (267 – 277) 132 (127 – 136) 149 (146 – 153) 268 (262 – 273) 522 (508 – 535) 604 (576 – 642) 8,498

Race/ethnicityMexican Americans 247 (242 – 252) 133 (125 – 138) 149 (138 – 155) 241 (237 – 246) 452 (434 – 465) 529 (506 – 558) 4,304

Non-Hispanic Blacks 214 (210 – 218) 112 (107 – 116) 125 (120 – 130) 213 (210 – 216) 382 (367 – 398) 428 (419 – 449) 4,404

Non-Hispanic Whites 281 (274 – 288) 144 (137 – 149) 160 (154 – 165) 276 (269 – 282) 529 (510 – 537) 617 (594 – 653) 6,675
-

1−5 6−11 12−19 20−39 40−59 60+ 

0 100 200 300 400 

Red blood cell folate

(ng/mL) 

Overall 

1−5 6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

400

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 1.2.a. Red blood cell folate: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Red blood cell folate Red blood cell folate (ng/mL) (ng/mL) 0 100 200 300 400 0 100 200 300 

1−5 6−11 12−19 20−39 40−59 60+ 1−5 6−11 12−19 20−39 40−59 60+ 

Females Males 

1−5 6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

1−5 6−11 12−19 20−39 40−59 60+ 

1. Water Soluble Vitamins 29
30 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.2.a.2. Red blood cell folate: Total population

Geometric mean and selected percentiles of red blood cell concentrations (in ng/mL) for the total U.S. 

population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 265 (261 – 270) 149 (146 – 152) 261 (256 – 265) 501 (487 – 515) 16,670

1–5 years 272 (265 – 279) 174 (169 – 178) 266 (261 – 272) 483 (436 – 531) 1,861

6–11 years 263 (258 – 268) 180 (172 – 184) 259 (254 – 264) 430 (400 – 456) 1,779

12–19 years 229 (225 – 234) 140 (134 – 146) 229 (224 – 233) 370 (355 – 390) 4,050

20–39 years 244 (238 – 250) 140 (136 – 144) 241 (235 – 247) 449 (421 – 480) 3,262

40–59 years 270 (264 – 276) 149 (143 – 154) 273 (266 – 279) 481 (461 – 510) 2,649

60 years and older 324 (317 – 332) 161 (157 – 166) 327 (315 – 338) 656 (622 – 705) 3,069

Males

Total, 1 year and older 259 (253 – 264) 149 (144 – 153) 255 (250 – 259) 469 (453 – 489) 8,172

1–5 years 281 (271 – 290) 176 (170 – 185) 271 (264 – 281) 507 (460 – 560) 941

6–11 years 265 (259 – 271) 182 (173 – 188) 257 (251 – 264) 439 (414 – 468) 867

12–19 years 229 (225 – 234) 142 (135 – 148) 229 (223 – 233) 361 (353 – 385) 2,051

20–39 years 235 (228 – 242) 140 (131 – 148) 235 (226 – 244) 397 (379 – 429) 1,467

40–59 years 263 (256 – 271) 149 (140 – 154) 265 (256 – 275) 463 (431 – 513) 1,309

60 years and older 313 (302 – 324) 159 (154 – 163) 311 (297 – 328) 651 (595 – 709) 1,537

Females

Total, 1 year and older 272 (267 – 277) 149 (146 – 153) 268 (262 – 273) 522 (508 – 535) 8,498

1–5 years 263 (255 – 270) 173 (161 – 177) 262 (254 – 267) 436 (395 – 531) 920

6–11 years 261 (254 – 269) 176 (162 – 183) 260 (253 – 267) 402 (379 – 459) 912

12–19 years 229 (223 – 234) 138 (130 – 146) 229 (223 – 234) 373 (354 – 398) 1,999

20–39 years 253 (246 – 261) 139 (134 – 145) 248 (239 – 258) 486 (461 – 529) 1,795

40–59 years 276 (269 – 284) 149 (139 – 157) 278 (271 – 288) 501 (467 – 536) 1,340

60 years and older 334 (324 – 344) 162 (157 – 172) 338 (325 – 352) 661 (616 – 744) 1,532

Table 1.2.a.3. Red blood cell folate: Mexican Americans

Geometric mean and selected percentiles of red blood cell concentrations (in ng/mL) for Mexican Americans in 

the U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 247 (242 – 252) 149 (138 – 155) 241 (237 – 246) 452 (434 – 465) 4,304

1–5 years 266 (257 – 275) 170 (152 – 177) 258 (249 – 266) 477 (441 – 507) 610

6–11 years 259 (252 – 266) 170 (156 – 183) 256 (249 – 262) 443 (396 – 483) 595

12–19 years 231 (225 – 237) 144 (136 – 154) 225 (221 – 232) 402 (386 – 423) 1,288

20–39 years 237 (228 – 246) 139 (125 – 154) 232 (223 – 241) 437 (402 – 463) 787

40–59 years 254 (245 – 264) 149 (132 – 157) 249 (235 – 264) 451 (415 – 520) 471

60 years and older 277 (263 – 292) 147 (130 – 156) 271 (258 – 290) 565 (483 – 646) 553

Males

Total, 1 year and older 238 (231 – 245) 146 (133 – 153) 234 (230 – 239) 413 (388 – 445) 2,087

1–5 years 276 (263 – 289) 171 (151 – 189) 267 (260 – 275) 481 (445 – 553) 298

6–11 years 263 (253 – 274) 171 (151 – 189) 258 (249 – 265) 466 (422 – 523) 289

12–19 years 226 (219 – 233) 139 (134 – 147) 223 (214 – 230) 378 (340 – 455) 639

20–39 years 221 (211 – 231) 136 (106 – 153) 220 (211 – 231) 367 (333 – 406) 350

40–59 years 245 (235 – 255) 149 (122 – 158) 234 (226 – 250) 429 (373 – 538) 238

60 years and older 257 (243 – 271) 146 (121 – 150) 248 (234 – 268) 478 (438 – 542) 273

Females

Total, 1 year and older 257 (252 – 263) 154 (140 – 161) 250 (246 – 256) 477 (460 – 505) 2,217

1–5 years 255 (245 – 265) 165 (139 – 177) 248 (240 – 258) 445 (398 – 506) 312

6–11 years 254 (245 – 263) 170 (153 – 180) 253 (246 – 261) 405 (358 – 477) 306

12–19 years 237 (230 – 243) 153 (135 – 158) 230 (224 – 237) 420 (398 – 450) 649

20–39 years 256 (247 – 267) 149 (135 – 161) 250 (236 – 267) 490 (458 – 587) 437

40–59 years 264 (249 – 281) 144 (110 – 159) 263 (244 – 287) 486 (424 – 746) 233

60 years and older 295 (269 – 322) 148 (91.6 – 168) 306 (267 – 329) 587 (550 – 682) 280
1. Water-Soluble Vitamins 31

Table 1.2.a.4. Red blood cell folate: Non–Hispanic blacks

Geometric mean and selected percentiles of red blood cell concentrations (in ng/mL) for non–Hispanic blacks 

in the U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 214 (210 – 218) 125 (120 – 130) 213 (210 – 216) 382 (367 – 398) 4,404

1–5 years 225 (218 – 232) 143 (132 – 152) 226 (221 – 231) 350 (330 – 371) 525

6–11 years 230 (225 – 235) 156 (146 – 165) 231 (224 – 238) 336 (321 – 370) 572

12–19 years 194 (190 – 199) 118 (111 – 124) 195 (191 – 200) 312 (299 – 319) 1,432

20–39 years 204 (199 – 210) 119 (115 – 122) 203 (193 – 209) 370 (350 – 406) 717

40–59 years 216 (208 – 225) 124 (107 – 132) 215 (209 – 221) 386 (359 – 436) 630

60 years and older 242 (231 – 254) 131 (125 – 137) 237 (221 – 252) 449 (423 – 508) 528

Males

Total, 1 year and older 209 (205 – 213) 122 (119 – 129) 208 (204 – 213) 355 (344 – 375) 2,189

1–5 years 228 (219 – 238) 143 (122 – 152) 227 (220 – 235) 359 (333 – 418) 259

6–11 years 231 (225 – 237) 164 (146 – 170) 231 (222 – 239) 337 (319 – 386) 282

12–19 years 195 (190 – 201) 123 (110 – 131) 198 (190 – 204) 305 (289 – 320) 750

20–39 years 195 (188 – 201) 116 (113 – 121) 192 (184 – 204) 309 (298 – 337) 339

40–59 years 211 (202 – 220) 120 (95.7 – 133) 209 (201 – 218) 375 (355 – 435) 295

60 years and older 233 (222 – 245) 128 (123 – 134) 224 (211 – 240) 461 (413 – 541) 264

Females

Total, 1 year and older 219 (214 – 224) 127 (119 – 131) 216 (212 – 221) 397 (374 – 416) 2,215

1–5 years 221 (214 – 228) 146 (124 – 158) 224 (218 – 232) 334 (301 – 361) 266

6–11 years 230 (221 – 239) 149 (142 – 161) 230 (219 – 242) 334 (314 – 388) 290

12–19 years 193 (188 – 200) 113 (109 – 119) 194 (190 – 200) 314 (299 – 341) 682

20–39 years 213 (204 – 221) 121 (108 – 132) 210 (199 – 219) 406 (371 – 428) 378

40–59 years 221 (210 – 233) 128 (99.8 – 133) 219 (211 – 232) 389 (353 – 494) 335

60 years and older 248 (232 – 267) 135 (104 – 150) 245 (220 – 275) 445 (421 – 521) 264

Table 1.2.a.5. Red blood cell folate: Non–Hispanic whites

Geometric mean and selected percentiles of red blood cell concentrations (in ng/mL) for non–Hispanic whites 

in the U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 281 (274 – 288) 160 (154 – 165) 276 (269 – 282) 529 (510 – 537) 6,675

1–5 years 290 (277 – 304) 191 (179 – 201) 278 (267 – 293) 528 (484 – 598) 523

6–11 years 274 (267 – 281) 191 (187 – 197) 268 (261 – 275) 439 (411 – 464) 454

12–19 years 239 (233 – 246) 152 (145 – 158) 238 (231 – 246) 376 (356 – 407) 1,046

20–39 years 258 (250 – 267) 152 (143 – 159) 254 (246 – 262) 464 (435 – 504) 1,460

40–59 years 281 (273 – 290) 159 (150 – 165) 285 (275 – 293) 494 (466 – 532) 1,346

60 years and older 339 (330 – 348) 173 (162 – 183) 340 (328 – 350) 673 (645 – 732) 1,846

Males

Total, 1 year and older 274 (267 – 281) 161 (153 – 167) 269 (262 – 278) 493 (473 – 524) 3,294

1–5 years 299 (284 – 316) 200 (173 – 208) 283 (268 – 312) 537 (498 – 659) 286

6–11 years 277 (268 – 286) 193† (188 – 202) 269 (258 – 278) 447† (425 – 517) 218

12–19 years 241 (234 – 248) 152 (139 – 158) 238 (231 – 249) 374 (355 – 437) 527

20–39 years 250 (240 – 260) 154 (141 – 165) 248 (238 – 258) 414 (395 – 447) 641

40–59 years 275 (265 – 286) 160 (148 – 165) 280 (266 – 292) 474 (433 – 534) 688

60 years and older 326 (314 – 338) 170 (161 – 184) 322 (306 – 340) 660 (609 – 716) 934

Females

Total, 1 year and older 288 (280 – 296) 158 (153 – 164) 282 (273 – 290) 546 (531 – 569) 3,381

1–5 years 280 (264 – 296) 183 (152 – 196) 272 (263 – 286) 486 (428 – 584) 237

6–11 years 270 (261 – 280) 188 (170 – 198) 267 (259 – 276) 390 (373 – 456) 236

12–19 years 238 (231 – 245) 149 (136 – 160) 237 (230 – 244) 381 (350 – 447) 519

20–39 years 267 (257 – 278) 149 (139 – 155) 263 (251 – 272) 502 (473 – 557) 819

40–59 years 287 (277 – 298) 158 (148 – 167) 289 (276 – 302) 506 (477 – 545) 658

60 years and older 350 (337 – 362) 177 (158 – 186) 352 (338 – 370) 689 (630 – 796) 912

† Estimate is subject to greater uncertainty due to small cell size.
32 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.2.b. Red blood cell folate: Concentrations by survey cycle

Geometric mean and selected percentiles of red blood cell concentrations (in ng/mL) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 3 years and older

 1999–2000 281 (269 – 293) 153 (144 – 162) 277 (266 – 288) 522 (499 – 556) 7,614

 2001–2002 277 (269 – 285) 155 (148 – 160) 274 (265 – 282) 519 (500 – 540) 8,488

 2003–2004 258 (251 – 266) 146 (139 – 151) 254 (246 – 262) 483 (464 – 506) 7,849

 2005–2006 272 (267 – 277) 152 (148 – 155) 267 (263 – 270) 517 (497 – 534) 7,906

Age group

3–5 years

 1999–2000 293 (282 – 306) 198 (182 – 206) 290 (283 – 301) 446 (397 – 608) 380

 2001–2002 284 (273 – 296) 188 (163 – 201) 283 (270 – 296) 468 (394 – 522) 460

 2003–2004 263 (253 – 273) 181 (172 – 187) 258 (245 – 268) 385 (364 – 583) 453

 2005–2006 282 (269 – 295) 191 (181 – 197) 271 (265 – 281) 463 (432 – 598) 493

6–11 years

 1999–2000 284 (275 – 293) 190 (177 – 202) 282 (274 – 292) 423 (389 – 502) 898

 2001–2002 276 (266 – 287) 183 (171 – 189) 272 (260 – 283) 444 (422 – 512) 1,040

 2003–2004 258 (251 – 265) 176 (170 – 183) 255 (246 – 264) 414 (372 – 447) 849

 2005–2006 269 (260 – 277) 182 (173 – 189) 263 (257 – 271) 434 (396 – 494) 930

12–19 years

 1999–2000 247 (237 – 256) 152 (146 – 158) 244 (238 – 255) 415 (391 – 456) 2,136

 2001–2002 242 (231 – 253) 148 (138 – 157) 238 (228 – 249) 406 (381 – 446) 2,226

 2003–2004 223 (217 – 230) 137 (129 – 145) 223 (215 – 230) 356 (338 – 386) 2,063

 2005–2006 235 (229 – 241) 145 (133 – 151) 234 (228 – 240) 380 (358 – 414) 1,987

20–39 years

 1999–2000 256 (244 – 268) 141 (130 – 150) 254 (237 – 270) 460 (439 – 515) 1,474

 2001–2002 254 (246 – 263) 144 (134 – 152) 251 (240 – 262) 448 (432 – 471) 1,721

 2003–2004 236 (228 – 245) 138 (131 – 143) 234 (221 – 245) 426 (403 – 461) 1,555

 2005–2006 252 (244 – 261) 143 (138 – 150) 249 (242 – 256) 462 (428 – 525) 1,707

40–59 years

 1999–2000 294 (279 – 311) 156 (144 – 167) 292 (274 – 309) 538 (502 – 613) 1,213

 2001–2002 289 (280 – 298) 163 (155 – 170) 287 (281 – 295) 526 (484 – 585) 1,496

 2003–2004 264 (253 – 275) 148 (137 – 156) 270 (258 – 279) 465 (430 – 514) 1,273

 2005–2006 276 (270 – 282) 150 (145 – 155) 277 (270 – 284) 495 (465 – 544) 1,376

60 years and older

 1999–2000 340 (328 – 352) 169 (154 – 182) 343 (323 – 363) 667 (629 – 701) 1,513

 2001–2002 334 (323 – 345) 167 (158 – 178) 336 (325 – 349) 654 (608 – 721) 1,545

 2003–2004 320 (310 – 329) 162 (154 – 171) 321 (310 – 337) 642 (589 – 725) 1,656

 2005–2006 329 (316 – 342) 161 (155 – 168) 332 (312 – 347) 662 (618 – 733) 1,413

Gender

Males

 1999–2000 274 (262 – 286) 153 (144 – 161) 270 (259 – 280) 499 (478 – 526) 3,721

 2001–2002 269 (259 – 278) 155 (147 – 160) 265 (254 – 276) 485 (465 – 520) 4,106

 2003–2004 252 (244 – 260) 147 (138 – 153) 248 (239 – 257) 452 (431 – 485) 3,874

 2005–2006 264 (257 – 271) 151 (144 – 157) 259 (255 – 264) 481 (459 – 508) 3,845

Females

 1999–2000 288 (275 – 301) 154 (142 – 164) 286 (272 – 298) 549 (515 – 590) 3,893

 2001–2002 285 (276 – 294) 155 (148 – 159) 282 (274 – 291) 540 (518 – 575) 4,382

 2003–2004 264 (256 – 273) 146 (138 – 151) 261 (251 – 271) 502 (483 – 530) 3,975

 2005–2006 280 (273 – 287) 153 (148 – 157) 274 (267 – 282) 538 (528 – 557) 4,061

Race/ethnicity

Mexican Americans

 1999–2000 261 (253 – 268) 159 (151 – 166) 256 (251 – 262) 452 (429 – 465) 2,592

 2001–2002 256 (244 – 268) 146 (132 – 161) 252 (241 – 265) 458 (434 – 497) 2,134

 2003–2004 242 (234 – 251) 149 (136 – 157) 236 (231 – 244) 414 (398 – 462) 1,919

 2005–2006 250 (244 – 256) 148 (129 – 158) 244 (239 – 249) 461 (452 – 482) 2,057

Non-Hispanic Blacks

 1999–2000 225 (218 – 233) 125 (113 – 135) 226 (221 – 234) 386 (366 – 427) 1,738

 2001–2002 216 (210 – 222) 122 (119 – 124) 214 (208 – 220) 376 (355 – 412) 2,045

 2003–2004 209 (203 – 214) 119 (114 – 127) 209 (204 – 214) 366 (349 – 389) 2,091

 2005–2006 220 (215 – 224) 131 (124 – 136) 217 (212 – 221) 402 (376 – 422) 2,084

Non-Hispanic Whites

 1999–2000 298 (281 – 315) 165 (147 – 175) 293 (275 – 309) 555 (527 – 592) 2,585

 2001–2002 293 (286 – 300) 166 (160 – 172) 289 (283 – 295) 542 (524 – 566) 3,625

 2003–2004 273 (262 – 285) 158 (146 – 166) 269 (258 – 280) 504 (485 – 531) 3,256

 2005–2006 288 (281 – 295) 162 (155 – 167) 282 (276 – 289) 539 (527 – 567) 3,149
-

Figure 1.2.b. Red blood cell folate: Concentrations by survey cycle 

Selected percentiles in ng/mL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006 

700 

600 

i 

i 

i i 

i 

i 

i 

i 

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i 

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i i 

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i 

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500 

400 

300 

350 

300 

250 

200 

i i 

i 

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50th Percentile 95th Percentile 

250 

200 

150 

100 

i i 

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i i 

i 

i 

i 

i i 

i 

i i i i i i i 

i i i i 

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i i i 

i i i 

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i i 

i i

5th Percentile 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(3+y) 

1. Water Soluble Vitamins 33
34 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.2.c. Red blood cell folate: Prevalence

Prevalence (in percent) of low red blood cell folate concentration (< 95 ng/mL) for the U.S. population 

aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Sample

size

Prevalence 

(95% conf. interval)

Estimated total 

number of persons

Total, 1 year and older 16,670 0.2 (0.2 – 0.4) 704,000

Age group

1–5 years 1,861 § §

6–11 years 1,779 § §

12–19 years 4,050 0.2 (0.1 – 0.4) 76,000

20–39 years 3,262 § §

40–59 years 2,649 0.4 (0.2 – 0.7) 331,000

60 years and older 3,069 § §

Gender

Males 8,172 0.2 (0.1 – 0.4) 301,000

Females 8,498 0.3 (0.2 – 0.5) 404,000

Race/ethnicity

Mexican Americans 4,304 0.3‡ (0.1 – 0.6) 72,000‡

Non-Hispanic Blacks 4,404 0.9 (0.6 – 1.5) 313,000

Non-Hispanic Whites 6,675 § §

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
1. Water-Soluble Vitamins 35

Table 1.2.d. Red blood cell folate: Prevalence by survey cycle

Prevalence (in percent) of low red blood cell folate concentration (< 95 ng/mL) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006.

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 3 years and older

 1999–2000 7,614 § §

 2001–2002 8,488 0.2‡ (0.1 – 0.4) 562,000‡

 2003–2004 7,849 0.3 (0.2 – 0.6) 947,000

 2005–2006 7,906 0.2 (0.1 – 0.3) 434,000

Age group

3–5 years

 1999–2000 380 § §

 2001–2002 460 § §

 2003–2004 453 § §

 2005–2006 493 § §

6–11 years

 1999–2000 898 § §

 2001–2002 1,040 § §

 2003–2004 849 § §

 2005–2006 930 § §

12–19 years

 1999–2000 2,136 § §

 2001–2002 2,226 § §

 2003–2004 2,063 0.3‡ (0.1 – 0.5) 88,000‡

 2005–2006 1,987 0.2‡ (0.1 – 0.4) 64,000‡

20–39 years

 1999–2000 1,474 § §

 2001–2002 1,721 § §

 2003–2004 1,555 § §

 2005–2006 1,707 § §

40–59 years

 1999–2000 1,213 § §

 2001–2002 1,496 § §

 2003–2004 1,273 0.7‡ (0.3 – 1.5) 555,000‡

 2005–2006 1,376 0.1‡ (0.1 – 0.3) 118,000‡

60 years and older

 1999–2000 1,513 § §

 2001–2002 1,545 0.3‡ (0.1 – 0.7) 147,000‡

 2003–2004 1,656 § §

 2005–2006 1,413 § §

Gender

Males

 1999–2000 3,721 0.2‡ (0.1 – 0.4) 217,000‡

 2001–2002 4,106 § §

 2003–2004 3,874 0.3‡ (0.1 – 0.6) 378,000‡

 2005–2006 3,845 0.1 (0.1 – 0.2) 201,000

Females

 1999–2000 3,893 § §

 2001–2002 4,382 0.1‡ (0.1 – 0.3) 161,000‡

 2003–2004 3,975 0.4‡ (0.2 – 0.9) 570,000‡

 2005–2006 4,061 § §

Race/ethnicity

Mexican Americans

 1999–2000 2,592 § §

 2001–2002 2,134 § §

 2003–2004 1,919 § §

 2005–2006 2,057 § §

Non-Hispanic Blacks

 1999–2000 1,738 1.0 (0.5 – 1.7) 318,000

 2001–2002 2,045 0.7‡ (0.3 – 1.5) 238,000‡

 2003–2004 2,091 1.0 (0.5 – 1.9) 333,000

 2005–2006 2,084 0.8‡ (0.3 – 1.8) 261,000‡

Non-Hispanic Whites

 1999–2000 2,585 § §

 2001–2002 3,625 § §

 2003–2004 3,256 § §

 2005–2006 3,149 0.0 (0.0 – 0.1) 85,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
36

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.3.a.1. Serum pyridoxal-5’-phosphate: Concentrations

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for the total U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 1 year and older 51.4 (49.1 – 53.8) 11.3 (10.0 – 12.5) 14.3 (13.3 – 15.3) 49.3 (46.9 – 51.2) 214 (199 – 245) 302 (279 – 330) 8,311Age group1–5 years 65.0 (61.2 – 69.0) 20.7 (18.2 – 23.6) 25.4 (21.3 – 29.9) 66.1 (63.1 – 70.4) 160 (148 – 182) 185 (176 – 202) 915

6–11 years 60.5 (56.9 – 64.4) 22.9 (20.0 – 24.1) 25.5 (23.3 – 28.2) 60.0 (55.3 – 65.5) 157 (137 – 185) 188 (169 – 223) 922

12–19 years 49.4 (46.7 – 52.3) 17.4 (16.4 – 18.4) 20.7 (19.2 – 21.6) 47.8 (44.9 – 51.0) 127 (118 – 150) 174 (140 – 206) 1,985

20–39 years 51.0 (47.7 – 54.6) 11.8 (10.3 – 13.7) 15.6 (13.6 – 17.0) 47.3 (43.9 – 50.5) 219 (194 – 273) 322 (279 – 379) 1,699

40–59 years 49.0 (45.1 – 53.3) 9.84 (8.61 – 11.3) 12.8 (11.2 – 13.8) 45.6 (41.5 – 50.3) 262 (212 – 302) 342 (297 – 399) 1,381

60 years and older 50.4 (46.7 – 54.5) 9.13 (8.70 – 9.95) 11.6 (9.96 – 12.9) 46.9 (41.9 – 53.5) 262 (217 – 311) 324 (281 – 385) 1,409

GenderMales 56.0 (53.6 – 58.5) 13.3 (11.7 – 14.5) 17.1 (15.2 – 18.9) 53.9 (52.0 – 56.0) 209 (191 – 254) 320 (282 – 352) 4,055

Females 47.4 (44.7 – 50.3) 10.2 (9.46 – 11.2) 12.9 (11.7 – 13.9) 44.1 (40.8 – 47.0) 222 (210 – 249) 291 (266 – 323) 4,256

Race/ethnicityMexican Americans 49.3 (47.2 – 51.4) 12.9 (10.8 – 14.7) 17.5 (14.5 – 19.5) 46.4 (44.9 – 48.3) 157 (147 – 174) 212 (190 – 262) 2,212

Non-Hispanic Blacks 40.5 (37.4 – 44.0) 9.41 (8.45 – 10.5) 12.7 (11.3 – 13.2) 39.0 (35.9 – 41.7) 155 (129 – 212) 238 (183 – 302) 2,157

Non-Hispanic Whites 53.8 (50.8 – 57.0) 11.3 (9.84 – 12.8) 14.1 (12.9 – 15.3) 51.7 (49.5 – 54.6) 234 (212 – 269) 319 (289 – 344) 3,285
-

1−5 6−11 12−19 20−39 40−59 60+ 

0 20 40 60 80 

Serum pyridoxal− 5'−phospate (nmol/L) 

Overall 

1−5 6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

80

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 1.3.a. Serum pyridoxal−5'−phosphate: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006 Serum pyridoxal− Serum pyridoxal− 5'−phospate (nmol/L) 5'−phospate (nmol/L) 0 20 40 60 80 0 20 40 60 

1−5 6−11 12−19 20−39 40−59 60+ 1−5 6−11 12−19 20−39 40−59 60+ 

Females Males 

1−5 6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

1−5 6−11 12−19 20−39 40−59 60+ 

1. Water Soluble Vitamins 37
38 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.3.a.2. Serum pyridoxal-5’-phosphate: Total population

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for the total U.S. population 

aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 1 year and older 51.4 (49.1 – 53.8) 19.5 (18.2 – 20.6) 49.3 (46.9 – 51.2) 154 (139 – 162) 8,311

1–5 years 65.0 (61.2 – 69.0) 31.7 (29.2 – 35.0) 66.1 (63.1 – 70.4) 126 (116 – 140) 915

6–11 years 60.5 (56.9 – 64.4) 30.7 (28.0 – 33.5) 60.0 (55.3 – 65.5) 126 (110 – 138) 922

12–19 years 49.4 (46.7 – 52.3) 24.8 (23.3 – 26.3) 47.8 (44.9 – 51.0) 105 (92.9 – 114) 1,985

20–39 years 51.0 (47.7 – 54.6) 20.0 (18.0 – 21.6) 47.3 (43.9 – 50.5) 153 (130 – 183) 1,699

40–59 years 49.0 (45.1 – 53.3) 16.5 (14.3 – 19.0) 45.6 (41.5 – 50.3) 166 (147 – 192) 1,381

60 years and older 50.4 (46.7 – 54.5) 15.1 (13.0 – 17.5) 46.9 (41.9 – 53.5) 187 (173 – 209) 1,409

Males

Total, 1 year and older 56.0 (53.6 – 58.5) 22.6 (20.3 – 24.6) 53.9 (52.0 – 56.0) 149 (136 – 162) 4,055

1–5 years 65.3 (61.2 – 69.6) 31.6 (26.3 – 35.2) 66.8 (63.2 – 71.9) 127 (117 – 135) 455

6–11 years 62.0 (57.4 – 66.9) 31.6 (30.5 – 33.4) 60.8 (54.8 – 68.4) 130 (113 – 143) 454

12–19 years 55.4 (52.4 – 58.6) 28.9 (27.0 – 30.6) 54.8 (51.3 – 57.9) 110 (101 – 122) 991

20–39 years 61.6 (58.0 – 65.4) 26.8 (24.8 – 28.8) 55.3 (52.7 – 58.3) 165 (139 – 202) 741

40–59 years 52.1 (46.4 – 58.5) 19.1 (14.8 – 22.6) 51.0 (43.7 – 56.9) 158 (125 – 188) 680

60 years and older 49.3 (44.7 – 54.3) 16.1 (13.5 – 19.3) 45.9 (40.0 – 54.4) 171 (156 – 196) 734

Females

Total, 1 year and older 47.4 (44.7 – 50.3) 17.2 (15.2 – 18.8) 44.1 (40.8 – 47.0) 156 (141 – 165) 4,256

1–5 years 64.6 (59.3 – 70.5) 32.1 (28.5 – 36.1) 65.2 (60.9 – 71.1) 124 (106 – 156) 460

6–11 years 59.1 (54.9 – 63.6) 29.7 (25.3 – 33.6) 58.3 (52.0 – 64.0) 118 (104 – 156) 468

12–19 years 43.7 (40.5 – 47.2) 21.8 (21.0 – 22.8) 41.4 (39.0 – 45.1) 90.6 (78.4 – 111) 994

20–39 years 42.4 (38.8 – 46.3) 16.5 (14.6 – 18.4) 37.6 (35.1 – 41.8) 132 (111 – 166) 958

40–59 years 46.4 (42.5 – 50.6) 14.4 (13.0 – 17.6) 41.6 (36.3 – 46.6) 172 (161 – 207) 701

60 years and older 51.4 (46.6 – 56.7) 14.1 (12.7 – 16.2) 47.6 (39.8 – 57.1) 206 (176 – 246) 675

Table 1.3.a.3. Serum pyridoxal-5’-phosphate: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for Mexican Americans in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 1 year and older 49.3 (47.2 – 51.4) 22.3 (19.8 – 23.9) 46.4 (44.9 – 48.3) 121 (105 – 136) 2,212

1–5 years 64.2 (60.1 – 68.7) 32.4 (28.0 – 34.2) 65.0 (59.0 – 71.1) 126 (115 – 142) 322

6–11 years 58.3 (52.5 – 64.6) 30.3 (24.0 – 34.9) 56.4 (50.8 – 65.8) 116 (98.9 – 137) 321

12–19 years 46.0 (44.4 – 47.6) 24.7 (23.0 – 26.6) 44.4 (42.5 – 47.6) 91.1 (83.7 – 100) 657

20–39 years 47.1 (44.1 – 50.4) 20.4 (15.7 – 24.8) 42.9 (40.1 – 45.6) 127 (97.0 – 143) 453

40–59 years 47.9 (42.4 – 54.1) 20.2 (14.5 – 23.3) 42.2 (38.5 – 49.4) 141 (115 – 170) 249

60 years and older 42.0 (34.9 – 50.5) 15.0 (13.1 – 17.2) 38.6 (30.2 – 50.1) 142 (101 – 184) 210

Males

Total, 1 year and older 56.4 (53.7 – 59.1) 27.9 (23.5 – 30.6) 53.7 (51.2 – 55.8) 124 (108 – 140) 1,056

1–5 years 67.0 (61.3 – 73.3) 30.4 (22.2 – 38.5) 67.7 (60.0 – 76.3) 129 (108 – 180) 153

6–11 years 61.4 (55.5 – 67.9) 32.0 (27.9 – 35.2) 57.5 (52.4 – 65.7) 126 (97.0 – 151) 157

12–19 years 53.0 (50.2 – 55.9) 28.2 (26.7 – 32.3) 51.6 (47.7 – 55.8) 104 (87.7 – 113) 318

20–39 years 57.2 (51.9 – 63.1) 29.4 (22.0 – 32.5) 51.9 (46.1 – 60.9) 135 (108 – 152) 200

40–59 years 56.7 (46.6 – 68.9) 24.0 (16.0 – 34.1) 53.3 (45.1 – 59.2) 122 (91.1 – 478) 123

60 years and older 37.8 (30.0 – 47.6) 14.7† (10.7 – 18.6) 35.6 (26.8 – 50.9) 95.5† (71.3 – 209) 105

Females

Total, 1 year and older 42.6 (40.8 – 44.6) 19.1 (16.4 – 20.8) 39.4 (38.2 – 40.3) 111 (96.5 – 130) 1,156

1–5 years 61.5 (55.9 – 67.7) 33.2 (28.9 – 34.9) 61.2 (55.2 – 68.8) 120 (97.3 – 176) 169

6–11 years 55.1 (47.2 – 64.3) 27.6 (17.6 – 34.7) 54.3 (44.6 – 68.7) 105 (87.9 – 133) 164

12–19 years 39.6 (37.6 – 41.7) 20.7 (19.0 – 22.6) 38.8 (37.2 – 39.7) 76.8 (69.9 – 87.9) 339

20–39 years 37.3 (34.3 – 40.4) 17.7 (11.8 – 19.6) 34.1 (31.7 – 36.1) 89.7 (71.6 – 134) 253

40–59 years 40.2 (35.0 – 46.3) 14.9 (10.3 – 18.9) 33.2 (29.7 – 39.1) 155 (110 – 199) 126

60 years and older 45.7 (36.9 – 56.6) 16.6† (12.6 – 19.8) 39.3 (30.7 – 53.3) 160† (106 – 212) 105

† Estimate is subject to greater uncertainty due to small cell size.
1. Water-Soluble Vitamins 39

Table 1.3.a.4. Serum pyridoxal-5’-phosphate: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for non-Hispanic blacks in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 1 year and older 40.5 (37.4 – 44.0) 16.3 (15.4 – 17.2) 39.0 (35.9 – 41.7) 104 (90.5 – 132) 2,157

1–5 years 54.0 (49.4 – 58.9) 25.2 (22.3 – 29.5) 51.2 (46.4 – 58.8) 115 (99.1 – 138) 226

6–11 years 50.6 (45.4 – 56.4) 27.2 (25.0 – 29.8) 46.4 (41.9 – 55.9) 97.1 (90.0 – 123) 254

12–19 years 41.0 (38.1 – 44.1) 21.6 (19.8 – 22.7) 39.5 (37.1 – 43.2) 82.8 (73.6 – 90.9) 676

20–39 years 40.5 (36.8 – 44.5) 16.3 (13.2 – 18.1) 38.5 (35.3 – 43.5) 105 (94.0 – 142) 371

40–59 years 39.9 (33.5 – 47.5) 14.9 (13.2 – 17.4) 36.3 (31.1 – 41.7) 132 (82.8 – 204) 339

60 years and older 31.3 (26.8 – 36.6) 10.7 (8.73 – 12.6) 29.1 (24.5 – 35.7) 104 (79.0 – 152) 291

Males

Total, 1 year and older 44.3 (40.5 – 48.6) 19.0 (17.3 – 20.1) 43.7 (39.3 – 47.3) 104 (92.0 – 137) 1,071

1–5 years 55.4 (49.5 – 61.9) 24.6† (19.3 – 32.2) 53.6 (46.6 – 60.4) 120† (103 – 147) 109

6–11 years 53.5 (47.2 – 60.7) 29.6 (26.0 – 31.8) 52.5 (41.9 – 61.7) 100 (92.0 – 124) 133

12–19 years 44.6 (40.6 – 48.9) 22.9 (21.1 – 25.1) 44.5 (38.8 – 49.5) 89.2 (74.9 – 103) 348

20–39 years 47.5 (41.2 – 54.8) 19.7 (14.5 – 23.5) 45.2 (37.7 – 53.5) 130 (95.2 – 185) 170

40–59 years 41.2 (34.9 – 48.7) 16.0 (9.17 – 20.7) 40.7 (31.6 – 46.6) 102 (79.6 – 203) 157

60 years and older 33.0 (27.9 – 39.1) 12.4 (10.2 – 13.4) 27.9 (24.1 – 38.1) 103 (79.1 – 194) 154

Females

Total, 1 year and older 37.5 (34.2 – 41.1) 14.8 (13.4 – 16.1) 35.6 (32.3 – 39.2) 103 (85.9 – 128) 1,086

1–5 years 52.5 (46.3 – 59.4) 26.0 (11.1 – 30.5) 51.1 (42.8 – 59.8) 109 (88.7 – 149) 117

6–11 years 47.9 (42.4 – 54.2) 25.0 (22.9 – 29.8) 42.9 (38.0 – 52.0) 93.0 (84.6 – 128) 121

12–19 years 37.7 (35.2 – 40.3) 20.7 (18.7 – 21.6) 36.8 (33.7 – 39.1) 73.6 (68.9 – 85.6) 328

20–39 years 35.4 (32.2 – 38.9) 14.4 (9.31 – 16.8) 33.8 (28.4 – 37.9) 99.7 (80.0 – 141) 201

40–59 years 38.8 (30.8 – 48.9) 14.4 (13.0 – 16.1) 33.8 (26.5 – 41.0) 145 (81.3 – 261) 182

60 years and older 30.2 (24.5 – 37.2) 9.48 (8.20 – 11.2) 29.9 (22.4 – 37.0) 95.0 (74.2 – 157) 137

† Estimate is subject to greater uncertainty due to small cell size

Table 1.3.a.5. Serum pyridoxal-5’-phosphate: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for non-Hispanic whites in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 1 year and older 53.8 (50.8 – 57.0) 19.2 (17.7 – 20.7) 51.7 (49.5 – 54.6) 167 (156 – 181) 3,285

1–5 years 68.5 (63.0 – 74.4) 34.0 (30.5 – 37.3) 68.4 (63.3 – 77.5) 130 (114 – 157) 263

6–11 years 63.9 (58.7 – 69.5) 31.6 (29.2 – 34.2) 63.3 (54.9 – 72.7) 133 (117 – 170) 251

12–19 years 52.7 (48.7 – 57.1) 25.7 (23.8 – 27.2) 51.5 (47.4 – 56.8) 109 (96.0 – 127) 505

20–39 years 54.3 (48.9 – 60.3) 20.9 (17.7 – 22.7) 50.6 (44.9 – 55.8) 168 (133 – 211) 718

40–59 years 50.6 (45.6 – 56.1) 16.2 (13.7 – 19.0) 47.9 (42.7 – 52.8) 173 (153 – 199) 691

60 years and older 53.2 (49.0 – 57.9) 15.7 (13.3 – 18.2) 50.6 (44.0 – 57.5) 196 (177 – 215) 857

Males

Total, 1 year and older 58.8 (55.1 – 62.7) 22.8 (20.2 – 25.5) 57.4 (53.8 – 60.6) 166 (147 – 183) 1,636

1–5 years 68.7 (62.9 – 74.9) 34.9 (30.2 – 37.2) 70.8 (65.3 – 78.3) 126 (115 – 137) 146

6–11 years 63.9 (57.3 – 71.4) 31.6 (29.3 – 33.7) 64.7 (50.1 – 75.8) 135 (106 – 190) 121

12–19 years 60.3 (55.5 – 65.5) 29.5 (27.3 – 33.8) 59.7 (54.7 – 65.2) 117 (105 – 148) 255

20–39 years 65.9 (60.4 – 72.0) 27.9 (25.3 – 30.8) 58.4 (53.9 – 66.8) 183 (152 – 228) 310

40–59 years 54.7 (47.4 – 63.2) 19.1 (14.6 – 22.8) 53.1 (43.6 – 61.7) 173 (140 – 194) 356

60 years and older 52.0 (46.4 – 58.2) 16.7 (13.7 – 20.5) 50.4 (42.2 – 59.3) 174 (157 – 204) 448

Females

Total, 1 year and older 49.4 (45.8 – 53.2) 16.4 (14.4 – 18.7) 46.4 (42.5 – 50.4) 170 (161 – 182) 1,649

1–5 years 68.3 (59.0 – 79.0) 32.6 (26.5 – 40.3) 66.6 (59.0 – 79.5) 141 (105 – 183) 117

6–11 years 63.8 (56.8 – 71.8) 31.3 (23.7 – 35.9) 62.7 (51.7 – 74.6) 126 (108 – 175) 130

12–19 years 45.6 (41.0 – 50.8) 21.8 (19.7 – 23.9) 42.1 (39.0 – 47.8) 94.0 (80.0 – 126) 250

20–39 years 44.6 (39.3 – 50.7) 16.5 (14.4 – 18.8) 38.4 (34.5 – 45.7) 156 (112 – 216) 408

40–59 years 46.8 (42.2 – 52.0) 13.9 (12.6 – 16.4) 44.4 (35.8 – 48.3) 174 (155 – 221) 335

60 years and older 54.3 (48.6 – 60.6) 14.6 (12.5 – 17.0) 50.6 (41.6 – 62.5) 213 (184 – 254) 409
40 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.3.c. Serum pyridoxal-5’-phosphate: Prevalence

Prevalence (in percent) of low serum pyridoxal-5’-phosphate concentration (< 20 nmol/L) for the U.S. 

population aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006.

Sample

size

Prevalence 

(95% conf. interval)

Estimated total

number of persons

Total, 1 year and older 8,311 10.5 (9.1 – 12.0) 30,146,000

Age group

1–5 years 915 2.1‡ (1.1 – 4.2) 435,000‡

6–11 years 922 1.2‡ (0.5 – 2.7) 280,000‡

12–19 years 1,985 4.6 (3.6 – 5.7) 1,529,000

20–39 years 1,699 9.9 (7.7 – 12.6) 7,877,000

40–59 years 1,381 13.9 (11.2 – 17.1) 11,371,000

60 years and older 1,409 16.0 (13.1 – 19.5) 7,741,000

Gender

Males 4,055 7.3 (5.7 – 9.4) 10,305,000

Females 4,256 13.5 (11.7 – 15.5) 19,830,000

Race/ethnicity

Mexican Americans 2,212 7.5 (5.3 – 10.4) 2,031,000

Non-Hispanic Blacks 2,157 15.7 (13.6 – 18.0) 5,459,000

Non-Hispanic Whites 3,285 10.7 (9.1 – 12.5) 20,588,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.
1. Water-Soluble Vitamins 41
42

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.4.a.1. Serum 4-pyridoxic acid: Concentrations

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for the total U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 1 year and older 31.9 (30.3 – 33.7) 8.73 (8.19 – 9.06) 9.87 (9.53 – 10.2) 25.5 (24.6 – 26.5) 194 (174 – 223) 385 (329 – 505) 8,312Age group1–5 years 25.9 (23.8 – 28.2) 8.90 (8.00 – 9.22) 10.5 (9.07 – 11.3) 24.2 (22.2 – 25.8) 96.9 (75.6 – 125) 130 (104 – 214) 917

6–11 years 23.5 (21.8 – 25.5) 8.11 (7.12 – 8.98) 9.46 (8.57 – 10.2) 21.6 (19.8 – 23.9) 85.6 (64.3 – 115) 111 (92.4 – 133) 922

12–19 years 20.9 (19.9 – 22.0) 7.74 (7.17 – 8.22) 8.85 (8.28 – 9.47) 19.0 (18.2 – 20.1) 70.5 (59.8 – 84.4) 94.5 (79.4 – 131) 1,985

20–39 years 26.8 (24.3 – 29.5) 8.02 (7.49 – 8.47) 9.16 (8.78 – 9.53) 22.2 (20.4 – 23.9) 160 (125 – 198) 271 (184 – 447) 1,698

40–59 years 34.7 (31.9 – 37.7) 9.36 (8.56 – 10.0) 10.7 (9.90 – 11.4) 27.3 (25.8 – 29.1) 212 (162 – 344) 705 (278 – 2,150) 1,381

60 years and older 58.6 (54.7 – 62.9) 11.6 (10.2 – 12.4) 13.1 (12.3 – 14.1) 47.6 (45.0 – 52.3) 464 (355 – 611) 873 (557 – 1,700) 1,409

GenderMales 32.1 (30.0 – 34.2) 9.24 (8.43 – 9.77) 10.6 (9.91 – 11.2) 26.0 (24.9 – 27.4) 171 (146 – 212) 334 (271 – 427) 4,055

Females 31.8 (30.2 – 33.5) 8.21 (7.89 – 8.65) 9.50 (9.15 – 9.76) 24.7 (23.4 – 26.1) 214 (188 – 255) 465 (349 – 712) 4,257

Race/ethnicityMexican Americans 22.5 (21.0 – 24.1) 7.90 (7.09 – 8.46) 9.13 (8.66 – 9.55) 19.0 (18.1 – 20.1) 90.9 (74.7 – 136) 169 (127 – 355) 2,213

Non-Hispanic Blacks 21.6 (19.4 – 24.0) 7.21 (6.78 – 7.57) 8.04 (7.72 – 8.44) 17.8 (16.3 – 19.3) 119 (89.8 – 196) 232 (159 – 493) 2,157

Non-Hispanic Whites 37.1 (35.1 – 39.1) 9.65 (9.04 – 10.1) 11.1 (10.6 – 11.5) 29.3 (27.8 – 30.6) 224 (203 – 265) 498 (370 – 717) 3,285
1−5 6−11 12−19 20−39 40−59 60+ 

0 20 40 60 80 

Serum 4−pyridoxic acid (nmol/L) 

Overall 

1−5 6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

80

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 1.4.a. Serum 4−pyridoxic acid: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006 Serum 4−pyridoxic acid (nmol/L) 0 20 40 60 Serum 4−pyridoxic acid (nmol/L) 0 20 40 60 80 

1−5 6−11 12−19 20−39 40−59 60+ 1−5 6−11 12−19 20−39 40−59 60+ 

Females Males 

1−5 6−11 12−19 20−39 40−59 60+ 1−5 6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

1. Water -Soluble Vitamins 43
44 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.4.a.2. Serum 4-pyridoxic acid: Total population

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for the total U.S. population 

aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 1 year and older 31.9 (30.3 – 33.7) 11.7 (11.4 – 12.2) 25.5 (24.6 – 26.5) 116 (105 – 128) 8,312

1–5 years 25.9 (23.8 – 28.2) 12.5 (11.4 – 13.3) 24.2 (22.2 – 25.8) 59.8 (49.8 – 79.6) 917

6–11 years 23.5 (21.8 – 25.5) 11.2 (10.2 – 12.0) 21.6 (19.8 – 23.9) 56.7 (48.4 – 71.5) 922

12–19 years 20.9 (19.9 – 22.0) 10.2 (9.88 – 10.6) 19.0 (18.2 – 20.1) 48.1 (44.1 – 54.5) 1,985

20–39 years 26.8 (24.3 – 29.5) 10.7 (10.0 – 11.1) 22.2 (20.4 – 23.9) 90.9 (73.2 – 115) 1,698

40–59 years 34.7 (31.9 – 37.7) 12.6 (11.8 – 13.6) 27.3 (25.8 – 29.1) 117 (105 – 138) 1,381

60 years and older 58.6 (54.7 – 62.9) 16.4 (14.9 – 18.3) 47.6 (45.0 – 52.3) 248 (208 – 321) 1,409

Males

Total, 1 year and older 32.1 (30.0 – 34.2) 12.9 (12.1 – 13.6) 26.0 (24.9 – 27.4) 103 (92.2 – 118) 4,055

1–5 years 26.7 (23.7 – 30.0) 11.9 (10.5 – 14.1) 25.2 (22.8 – 27.0) 63.6 (48.5 – 111) 456

6–11 years 24.0 (22.1 – 26.1) 11.6 (9.92 – 12.4) 21.9 (20.2 – 24.1) 56.4 (46.0 – 83.0) 454

12–19 years 23.3 (21.9 – 24.7) 11.9 (10.9 – 12.6) 20.8 (19.7 – 21.9) 55.0 (46.8 – 67.0) 991

20–39 years 29.0 (26.1 – 32.2) 12.0 (10.9 – 13.2) 24.3 (22.5 – 26.0) 89.5 (65.9 – 124) 740

40–59 years 33.0 (29.3 – 37.2) 13.8 (11.8 – 15.2) 26.5 (24.4 – 30.2) 101 (76.3 – 124) 680

60 years and older 56.7 (50.7 – 63.5) 17.2 (15.1 – 18.9) 46.8 (41.8 – 53.3) 220 (178 – 292) 734

Females

Total, 1 year and older 31.8 (30.2 – 33.5) 11.1 (10.9 – 11.3) 24.7 (23.4 – 26.1) 133 (116 – 151) 4,257

1–5 years 25.1 (23.3 – 27.1) 12.6 (11.9 – 13.0) 22.7 (20.8 – 25.4) 59.2 (48.3 – 76.4) 461

6–11 years 23.0 (20.5 – 25.8) 10.7 (9.57 – 11.5) 20.8 (18.6 – 24.2) 54.9 (44.7 – 90.5) 468

12–19 years 18.7 (17.7 – 19.8) 9.59 (9.31 – 9.88) 17.1 (16.3 – 18.0) 42.9 (35.5 – 52.2) 994

20–39 years 24.8 (22.3 – 27.5) 9.74 (9.31 – 10.4) 19.2 (17.3 – 22.1) 92.5 (77.5 – 118) 958

40–59 years 36.4 (33.3 – 39.8) 12.1 (11.3 – 12.7) 28.1 (25.2 – 31.1) 145 (116 – 192) 701

60 years and older 60.2 (56.1 – 64.8) 15.6 (14.0 – 17.9) 48.7 (43.5 – 56.9) 257 (219 – 328) 675

Table 1.4.a.3. Serum 4-pyridoxic acid: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for Mexican Americans in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 1 year and older 22.5 (21.0 – 24.1) 10.7 (10.0 – 11.2) 19.0 (18.1 – 20.1) 57.9 (48.0 – 66.1) 2,213

1–5 years 22.7 (20.7 – 24.8) 11.9 (10.7 – 12.8) 20.3 (19.1 – 22.2) 52.3 (41.3 – 62.3) 324

6–11 years 19.6 (17.7 – 21.7) 9.67 (8.75 – 10.7) 18.5 (16.0 – 20.3) 44.2 (36.3 – 58.1) 321

12–19 years 17.1 (16.4 – 17.8) 9.29 (8.70 – 9.81) 15.8 (14.8 – 16.8) 34.6 (31.5 – 42.8) 657

20–39 years 21.6 (19.3 – 24.1) 10.7 (9.33 – 11.4) 18.3 (16.8 – 19.9) 53.3 (43.8 – 76.4) 452

40–59 years 27.9 (24.6 – 31.6) 11.7 (10.1 – 12.7) 22.4 (20.5 – 24.6) 71.1 (60.0 – 114) 249

60 years and older 33.8 (27.9 – 41.0) 12.5 (11.0 – 14.7) 27.3 (23.6 – 31.2) 117 (75.3 – 311) 210

Males

Total, 1 year and older 23.6 (21.9 – 25.6) 11.5 (10.8 – 12.0) 20.7 (19.4 – 21.7) 58.1 (45.6 – 68.9) 1,057

1–5 years 23.3 (20.4 – 26.5) 11.8 (10.7 – 13.7) 20.9 (18.9 – 22.9) 48.8 (38.0 – 78.1) 155

6–11 years 20.7 (18.2 – 23.6) 10.3 (8.64 – 11.4) 18.9 (16.5 – 20.9) 47.4 (39.5 – 59.3) 157

12–19 years 19.4 (18.2 – 20.6) 10.3 (9.71 – 10.8) 17.3 (16.8 – 18.4) 41.6 (34.1 – 59.2) 318

20–39 years 23.0 (20.1 – 26.2) 11.2 (9.36 – 12.7) 19.5 (17.6 – 22.2) 55.0 (42.2 – 85.5) 199

40–59 years 29.7 (24.2 – 36.4) 12.9 (12.5 – 13.9) 24.2 (21.2 – 28.4) 65.1 (45.1 – 230) 123

60 years and older 28.2 (22.0 – 36.1) 11.6† (5.00 – 14.6) 26.0 (19.9 – 33.3) 72.5† (50.8 – 193) 105

Females

Total, 1 year and older 21.4 (20.1 – 22.7) 9.91 (9.35 – 10.6) 17.3 (16.4 – 18.3) 57.0 (49.5 – 70.1) 1,156

1–5 years 22.0 (19.9 – 24.4) 11.9 (9.70 – 12.5) 20.2 (17.5 – 22.6) 52.3 (38.6 – 64.8) 169

6–11 years 18.5 (16.3 – 21.1) 9.60 (7.35 – 10.7) 17.3 (15.1 – 20.4) 41.2 (31.1 – 53.4) 164

12–19 years 15.0 (14.3 – 15.8) 8.55 (7.66 – 9.16) 14.1 (13.2 – 15.1) 28.2 (25.2 – 33.6) 339

20–39 years 20.0 (17.6 – 22.8) 9.73 (7.90 – 11.1) 16.3 (14.7 – 18.6) 49.5 (41.4 – 81.1) 253

40–59 years 26.1 (22.4 – 30.3) 10.9 (9.79 – 11.6) 19.1 (14.7 – 25.2) 90.5 (54.6 – 289) 126

60 years and older 39.2 (30.0 – 51.4) 13.9† (11.1 – 15.7) 28.0 (23.3 – 35.2) 162† (78.4 – 3,380) 105

† Estimate is subject to greater uncertainty due to small cell size.
1. Water-Soluble Vitamins 45

Table 1.4.a.4. Serum 4-pyridoxic acid: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for non-Hispanic blacks in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 1 year and older 21.6 (19.4 – 24.0) 9.28 (8.85 – 9.59) 17.8 (16.3 – 19.3) 60.5 (51.3 – 81.9) 2,157

1–5 years 22.2 (19.2 – 25.8) 10.1 (8.17 – 11.2) 19.5 (17.6 – 22.5) 61.7 (44.0 – 96.8) 226

6–11 years 17.8 (16.0 – 19.8) 9.03 (8.25 – 9.53) 15.3 (14.3 – 17.4) 43.9 (32.5 – 67.1) 254

12–19 years 14.8 (14.0 – 15.7) 8.28 (7.64 – 8.65) 13.9 (13.1 – 14.6) 28.9 (25.7 – 34.0) 676

20–39 years 19.3 (18.1 – 20.7) 8.89 (8.39 – 9.47) 15.4 (14.2 – 17.6) 51.4 (45.3 – 60.6) 371

40–59 years 25.3 (21.3 – 30.0) 9.62 (8.24 – 10.8) 19.2 (17.6 – 21.2) 103 (57.1 – 164) 339

60 years and older 33.8 (26.3 – 43.4) 12.2 (9.71 – 14.1) 27.4 (23.1 – 30.6) 113 (81.9 – 246) 291

Males

Total, 1 year and older 21.8 (19.7 – 24.3) 9.68 (9.16 – 10.3) 18.5 (17.3 – 20.0) 55.7 (44.4 – 82.8) 1,070

1–5 years 24.5 (20.6 – 29.1) 10.3† (6.27 – 12.2) 20.9 (17.7 – 24.4) 83.7† (48.8 – 152) 108

6–11 years 18.4 (16.2 – 21.0) 9.50 (8.53 – 10.3) 15.9 (14.5 – 18.5) 44.1 (33.3 – 66.5) 133

12–19 years 16.2 (15.0 – 17.5) 9.11 (8.59 – 9.35) 15.5 (14.1 – 16.5) 30.9 (26.8 – 39.1) 348

20–39 years 19.7 (17.6 – 22.2) 9.68 (8.96 – 10.9) 17.4 (14.3 – 20.4) 44.3 (32.7 – 68.2) 170

40–59 years 25.1 (21.7 – 29.0) 9.58 (7.97 – 10.6) 19.3 (17.7 – 20.8) 71.2 (52.9 – 134) 157

60 years and older 33.2 (27.1 – 40.7) 12.5 (11.8 – 13.4) 24.3 (22.7 – 30.2) 109 (80.8 – 246) 154

Females

Total, 1 year and older 21.3 (18.7 – 24.3) 8.88 (8.38 – 9.44) 17.1 (15.0 – 19.1) 64.9 (52.5 – 94.0) 1,087

1–5 years 20.1 (16.7 – 24.2) 8.59 (7.62 – 11.1) 19.0 (16.1 – 22.5) 42.6 (34.5 – 65.2) 118

6–11 years 17.2 (15.1 – 19.7) 8.50 (7.72 – 9.43) 14.8 (13.1 – 17.4) 40.6 (31.1 – 86.4) 121

12–19 years 13.5 (12.6 – 14.4) 7.56 (6.46 – 8.33) 12.7 (11.8 – 13.4) 25.6 (22.0 – 32.8) 328

20–39 years 19.0 (16.9 – 21.5) 8.42 (7.62 – 8.98) 14.3 (12.7 – 16.9) 57.7 (45.3 – 85.7) 201

40–59 years 25.4 (19.2 – 33.7) 9.64 (7.95 – 11.0) 18.8 (15.5 – 25.8) 107 (53.1 – 217) 182

60 years and older 34.2 (24.3 – 48.1) 11.6 (8.02 – 15.3) 28.0 (21.9 – 33.8) 116 (75.1 – 431) 137

† Estimate is subject to greater uncertainty due to small cell size.

Table 1.4.a.5. Serum 4-pyridoxic acid: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for non-Hispanic whites in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 1 year and older 37.1 (35.1 – 39.1) 13.2 (12.6 – 13.8) 29.3 (27.8 – 30.6) 138 (120 – 154) 3,285

1–5 years 28.4 (25.2 – 31.8) 13.6 (11.9 – 15.1) 26.7 (24.2 – 29.2) 59.9 (49.8 – 104) 263

6–11 years 26.7 (24.1 – 29.5) 12.6 (11.8 – 13.3) 24.5 (22.4 – 26.0) 63.5 (50.7 – 96.3) 251

12–19 years 24.1 (22.4 – 26.0) 11.5 (10.6 – 12.8) 21.5 (21.0 – 22.2) 55.9 (47.7 – 74.7) 505

20–39 years 31.2 (27.5 – 35.4) 11.5 (10.7 – 12.6) 25.2 (22.6 – 28.1) 113 (89.1 – 155) 718

40–59 years 37.7 (34.1 – 41.6) 13.7 (12.5 – 14.8) 30.2 (27.9 – 32.2) 130 (111 – 148) 691

60 years and older 64.4 (58.5 – 70.9) 18.2 (15.3 – 20.2) 53.7 (48.7 – 57.9) 257 (220 – 328) 857

Males

Total, 1 year and older 36.8 (34.1 – 39.6) 14.9 (13.7 – 15.7) 29.5 (27.7 – 31.3) 116 (105 – 136) 1,636

1–5 years 29.0 (24.9 – 33.7) 14.0 (9.91 – 16.0) 27.2 (24.5 – 31.1) 59.8 (47.3 – 130) 146

6–11 years 26.4 (23.7 – 29.5) 12.5 (11.7 – 13.9) 24.9 (21.6 – 26.0) 66.7 (45.2 – 92.9) 121

12–19 years 27.1 (25.0 – 29.4) 14.2 (13.4 – 15.5) 23.5 (21.4 – 26.1) 64.0 (54.7 – 80.3) 255

20–39 years 33.6 (29.4 – 38.4) 14.4 (12.0 – 15.6) 26.9 (24.2 – 29.4) 105 (71.2 – 187) 310

40–59 years 35.5 (30.7 – 41.1) 14.9 (12.5 – 17.5) 29.3 (26.0 – 33.1) 102 (81.5 – 141) 356

60 years and older 62.6 (54.1 – 72.5) 18.8 (15.9 – 21.2) 52.3 (44.8 – 60.1) 232 (195 – 344) 448

Females

Total, 1 year and older 37.3 (35.4 – 39.4) 12.4 (11.6 – 12.7) 29.2 (26.8 – 31.4) 155 (136 – 176) 1,649

1–5 years 27.7 (24.5 – 31.3) 13.1 (11.1 – 15.1) 25.4 (20.8 – 29.9) 59.9 (49.8 – 99.2) 117

6–11 years 26.9 (22.4 – 32.3) 12.5 (10.7 – 13.7) 24.3 (20.7 – 29.2) 62.1 (47.7 – 189) 130

12–19 years 21.2 (19.2 – 23.5) 10.2 (9.58 – 11.0) 19.8 (18.0 – 21.1) 47.3 (40.3 – 69.4) 250

20–39 years 29.0 (25.5 – 33.0) 10.6 (9.87 – 11.0) 23.1 (19.3 – 26.9) 117 (90.2 – 161) 408

40–59 years 39.9 (35.9 – 44.5) 12.8 (12.1 – 13.6) 30.5 (26.6 – 34.8) 155 (128 – 223) 335

60 years and older 65.9 (60.1 – 72.4) 17.6 (14.1 – 20.4) 54.9 (47.4 – 63.8) 270 (242 – 343) 409
46

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.5.a.1. Serum vitamin B12: Concentrations

Geometric mean and selected percentiles of serum concentrations (in pg/mL) for the total U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 1 year and older 500 (489 – 511) 206 (201 – 212) 236 (227 – 244) 495 (483 – 505) 1,090 (1,050 – 1,110) 1,300 (1,250 – 1,340) 16,316Age group1–5 years 804 (776 – 833) 327 (280 – 368) 397 (344 – 432) 814 (783 – 858) 1,520 (1,470 – 1,630) 1,710 (1,600 – 1,810) 1,678

6–11 years 728 (713 – 743) 354 (342 – 363) 396 (367 – 431) 724 (707 – 747) 1,280 (1,240 – 1,350) 1,440 (1,360 – 1,570) 1,747

12–19 years 510 (499 – 521) 238 (224 – 250) 271 (264 – 277) 509 (495 – 526) 938 (901 – 975) 1,050 (1,020 – 1,140) 4,013

20–39 years 454 (443 – 465) 210 (201 – 214) 231 (223 – 243) 451 (441 – 462) 884 (859 – 904) 1,010 (962 – 1,060) 3,214

40–59 years 466 (451 – 482) 197 (177 – 210) 226 (214 – 237) 460 (446 – 475) 1,020 (934 – 1,100) 1,180 (1,110 – 1,350) 2,629

60 years and older 482 (468 – 496) 166 (151 – 179) 210 (202 – 217) 481 (466 – 499) 1,070 (1,020 – 1,190) 1,380 (1,280 – 1,570) 3,035

GenderMales 500 (490 – 509) 216 (210 – 222) 249 (238 – 259) 494 (484 – 505) 1,030 (994 – 1,060) 1,200 (1,150 – 1,240) 7,999

Females 500 (487 – 514) 200 (189 – 206) 227 (216 – 236) 495 (480 – 508) 1,140 (1,100 – 1,180) 1,370 (1,330 – 1,410) 8,317

Race/ethnicityMexican Americans 549 (530 – 569) 224 (212 – 241) 260 (248 – 274) 527 (513 – 547) 1,170 (1,110 – 1,240) 1,600 (1,370 – 1,950) 4,205

Non-Hispanic Blacks 565 (550 – 580) 223 (210 – 233) 266 (258 – 276) 556 (537 – 576) 1,240 (1,200 – 1,320) 1,430 (1,370 – 1,540) 4,285

Non-Hispanic Whites 482 (470 – 495) 201 (194 – 209) 229 (222 – 239) 478 (465 – 491) 1,040 (999 – 1,080) 1,230 (1,170 – 1,310) 6,571
1. Water-Soluble Vitamins 47

1−5 6−11 12−19 20−39 40−59 60+

0 500 1000

Serum vitamin B12

(pg/mL)

Overall

1−5 6−11 12−19 20−39 40−59 60+

Mexican Americans

Females

Males

1−5 6−11 12−19 20−39 40−59 60+

0 500 1000

Non−Hispanic Blacks

Serum vitamin B12

(pg/mL)

1−5 6−11 12−19 20−39 40−59 60+

Non−Hispanic Whites

1−5 6−11 12−19 20−39 40−59 60+

0 500 1000

Serum vitamin B12

(pg/mL)

Females

Age (years)

1−5 6−11 12−19 20−39 40−59 60+

Males

Age (years)

Mexican

 Americans

Non−Hispanic

 Blacks

Non−Hispanic

 Whites

Figure 1.5.a. Serum vitamin B12: Concentrations by age group

Geometric mean (95% condence interval), National Health and Nutrition Examination Survey, 2003–2006
48 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

 Table 1.5.a.2. Serum vitamin B12: Total population

Geometric mean and selected percentiles of serum concentrations (in pg/mL) for the total U.S. population aged 

1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 500 (489 – 511) 236 (227 – 244) 495 (483 – 505) 1,090 (1,050 – 1,110) 16,316

1–5 years 804 (776 – 833) 397 (344 – 432) 814 (783 – 858) 1,520 (1,470 – 1,630) 1,678

6–11 years 728 (713 – 743) 396 (367 – 431) 724 (707 – 747) 1,280 (1,240 – 1,350) 1,747

12–19 years 510 (499 – 521) 271 (264 – 277) 509 (495 – 526) 938 (901 – 975) 4,013

20–39 years 454 (443 – 465) 231 (223 – 243) 451 (441 – 462) 884 (859 – 904) 3,214

40–59 years 466 (451 – 482) 226 (214 – 237) 460 (446 – 475) 1,020 (934 – 1,100) 2,629

60 years and older 482 (468 – 496) 210 (202 – 217) 481 (466 – 499) 1,070 (1,020 – 1,190) 3,035

Males

Total, 1 year and older 500 (490 – 509) 249 (238 – 259) 494 (484 – 505) 1,030 (994 – 1,060) 7,999

1–5 years 796 (761 – 832) 379 (302 – 423) 816 (775 – 862) 1,470 (1,430 – 1,520) 844

6–11 years 722 (701 – 744) 411 (363 – 439) 735 (713 – 761) 1,220 (1,140 – 1,270) 853

12–19 years 513 (500 – 526) 292 (272 – 309) 510 (494 – 534) 904 (866 – 951) 2,031

20–39 years 469 (456 – 483) 258 (242 – 270) 469 (454 – 485) 856 (820 – 893) 1,451

40–59 years 456 (440 – 472) 226 (212 – 246) 456 (442 – 469) 896 (825 – 985) 1,296

60 years and older 461 (447 – 475) 210 (193 – 223) 458 (442 – 480) 990 (937 – 1,100) 1,524

Females

Total, 1 year and older 500 (487 – 514) 227 (216 – 236) 495 (480 – 508) 1,140 (1,100 – 1,180) 8,317

1–5 years 813 (781 – 847) 401 (343 – 444) 810 (772 – 863) 1,560 (1,470 – 1,740) 834

6–11 years 734 (710 – 758) 393 (362 – 421) 714 (687 – 748) 1,360 (1,290 – 1,460) 894

12–19 years 506 (492 – 520) 254 (243 – 266) 507 (487 – 526) 973 (928 – 1,050) 1,982

20–39 years 439 (425 – 453) 217 (206 – 227) 431 (420 – 446) 909 (868 – 980) 1,763

40–59 years 476 (455 – 499) 223 (200 – 241) 467 (444 – 489) 1,090 (1,020 – 1,160) 1,333

60 years and older 499 (479 – 521) 210 (200 – 218) 504 (477 – 530) 1,140 (1,050 – 1,310) 1,511

Table 1.5.a.3. Serum vitamin B12: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in pg/mL) for Mexican Americans in the U.S. 

population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 549 (530 – 569) 260 (248 – 274) 527 (513 – 547) 1,170 (1,110 – 1,240) 4,205

1–5 years 833 (802 – 866) 450 (417 – 468) 842 (811 – 880) 1,480 (1,390 – 1,670) 540

6–11 years 730 (708 – 753) 409 (367 – 441) 729 (704 – 762) 1,210 (1,150 – 1,290) 587

12–19 years 508 (493 – 524) 270 (250 – 295) 505 (486 – 525) 909 (873 – 951) 1,280

20–39 years 483 (463 – 503) 249 (225 – 260) 467 (449 – 493) 955 (883 – 1,150) 778

40–59 years 535 (491 – 582) 248 (207 – 274) 483 (457 – 515) 1,310 (996 – 3,160) 468

60 years and older 496 (465 – 528) 220 (193 – 239) 458 (435 – 489) 1,240 (1,070 – 2,490) 552

Males

Total, 1 year and older 526 (510 – 543) 258 (251 – 267) 513 (492 – 533) 1,060 (1,010 – 1,110) 2,036

1–5 years 801 (766 – 838) 423 (364 – 467) 805 (776 – 844) 1,450 (1,330 – 1,630) 261

6–11 years 724 (696 – 752) 386 (345 – 462) 735 (705 – 771) 1,150 (1,080 – 1,250) 285

12–19 years 498 (478 – 519) 271 (239 – 305) 494 (476 – 516) 866 (810 – 920) 637

20–39 years 467 (443 – 492) 252 (217 – 264) 459 (431 – 494) 855 (794 – 978) 345

40–59 years 493 (460 – 529) 249 (191 – 263) 463 (446 – 494) 1,050 (915 – 2,230) 236

60 years and older 456 (412 – 505) 224 (195 – 237) 404 (376 – 448) 1,210 (929 – 5,710) 272

Females

Total, 1 year and older 574 (548 – 602) 263 (241 – 288) 550 (522 – 573) 1,290 (1,180 – 1,630) 2,169

1–5 years 869 (824 – 916) 456 (420 – 500) 887 (834 – 910) 1,590 (1,400 – 1,890) 279

6–11 years 738 (704 – 772) 413 (370 – 441) 716 (690 – 762) 1,280 (1,160 – 1,620) 302

12–19 years 519 (502 – 536) 269 (255 – 291) 518 (495 – 549) 951 (892 – 1,060) 643

20–39 years 501 (476 – 528) 248 (220 – 271) 476 (452 – 509) 1,190 (984 – 2,080) 433

40–59 years 582 (500 – 678) 243 (182 – 306) 520 (464 – 574) 1,950 (1,010 – 6,830) 232

60 years and older 531 (475 – 594) 210 (169 – 258) 494 (459 – 537) 1,370 (1,110 – 2,950) 280
1. Water-Soluble Vitamins 49

Table 1.5.a.4. Serum vitamin B12: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in pg/mL) for non-Hispanic blacks in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 565 (550 – 580) 266 (258 – 276) 556 (537 – 576) 1,240 (1,200 – 1,320) 4,285

1–5 years 885 (835 – 938) 431 (340 – 479) 899 (827 – 965) 1,770 (1,550 – 2,020) 476

6–11 years 827 (800 – 854) 448 (398 – 470) 817 (800 – 842) 1,560 (1,440 – 1,670) 553

12–19 years 570 (557 – 584) 284 (270 – 297) 571 (551 – 585) 1,110 (1,050 – 1,160) 1,415

20–39 years 499 (483 – 516) 259 (227 – 277) 497 (480 – 512) 941 (894 – 1,050) 706

40–59 years 524 (506 – 543) 264 (220 – 286) 515 (494 – 544) 1,120 (1,070 – 1,200) 622

60 years and older 530 (504 – 558) 225 (199 – 252) 531 (505 – 565) 1,240 (1,100 – 1,510) 513

Males

Total, 1 year and older 564 (549 – 580) 267 (257 – 282) 546 (533 – 571) 1,230 (1,140 – 1,320) 2,136

1–5 years 896 (821 – 977) 418 (293 – 494) 910 (822 – 1,010) 1,800 (1,570 – 2,150) 236

6–11 years 799 (762 – 837) 428 (350 – 466) 811 (743 – 840) 1,540 (1,370 – 1,780) 272

12–19 years 567 (550 – 585) 294 (268 – 322) 567 (541 – 585) 1,040 (993 – 1,140) 742

20–39 years 512 (488 – 536) 277 (256 – 290) 507 (482 – 527) 950 (872 – 1,160) 337

40–59 years 510 (482 – 539) 241 (204 – 269) 509 (488 – 541) 988 (863 – 1,250) 292

60 years and older 502 (472 – 533) 211 (142 – 241) 494 (459 – 521) 1,220 (998 – 1,770) 257

Females

Total, 1 year and older 565 (545 – 587) 265 (233 – 282) 563 (531 – 597) 1,250 (1,200 – 1,340) 2,149

1–5 years 874 (829 – 922) 431 (257 – 489) 880 (798 – 957) 1,650 (1,470 – 2,050) 240

6–11 years 856 (815 – 899) 468 (383 – 501) 834 (801 – 887) 1,570 (1,430 – 1,710) 281

12–19 years 574 (558 – 590) 272 (259 – 288) 576 (551 – 595) 1,160 (1,110 – 1,210) 673

20–39 years 489 (464 – 515) 231 (207 – 271) 487 (460 – 518) 938 (880 – 1,080) 369

40–59 years 536 (507 – 566) 273 (219 – 295) 527 (492 – 568) 1,170 (1,100 – 1,400) 330

60 years and older 551 (514 – 590) 232 (187 – 265) 576 (524 – 613) 1,280 (1,110 – 1,620) 256

Table 1.5.a.5. Serum vitamin B12: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in pg/mL) for non-Hispanic whites in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 482 (470 – 495) 229 (222 – 239) 478 (465 – 491) 1,040 (999 – 1,080) 6,571

1–5 years 769 (730 – 810) 375 (298 – 411) 777 (730 – 830) 1,470 (1,410 – 1,560) 476

6–11 years 707 (686 – 729) 392 (345 – 435) 703 (674 – 734) 1,230 (1,170 – 1,350) 448

12–19 years 496 (484 – 509) 269 (253 – 276) 498 (481 – 517) 887 (833 – 952) 1,042

20–39 years 440 (426 – 455) 226 (215 – 238) 438 (424 – 452) 853 (814 – 889) 1,434

40–59 years 453 (435 – 471) 225 (208 – 236) 448 (434 – 465) 980 (867 – 1,090) 1,340

60 years and older 476 (461 – 492) 209 (200 – 217) 477 (460 – 499) 1,050 (990 – 1,170) 1,831

Males

Total, 1 year and older 487 (475 – 498) 244 (228 – 256) 483 (471 – 496) 981 (946 – 1,030) 3,235

1–5 years 764 (720 – 811) 353 (261 – 416) 799 (739 – 861) 1,380 (1,320 – 1,500) 254

6–11 years 708 (678 – 740) 405† (343 – 441) 715 (680 – 753) 1,160† (1,080 – 1,250) 216

12–19 years 507 (492 – 522) 293 (271 – 316) 505 (486 – 535) 847 (803 – 941) 523

20–39 years 468 (448 – 488) 263 (230 – 275) 469 (448 – 493) 826 (786 – 900) 631

40–59 years 447 (430 – 465) 226 (199 – 248) 448 (435 – 464) 879 (781 – 984) 682

60 years and older 454 (439 – 469) 208 (181 – 221) 455 (434 – 481) 952 (887 – 1,050) 929

Females

Total, 1 year and older 478 (462 – 494) 220 (210 – 230) 471 (454 – 488) 1,080 (1,040 – 1,140) 3,336

1–5 years 774 (721 – 831) 381† (325 – 431) 763 (700 – 835) 1,530† (1,450 – 1,760) 222

6–11 years 706 (671 – 743) 377 (316 – 421) 679 (648 – 742) 1,340 (1,180 – 1,490) 232

12–19 years 485 (470 – 501) 246 (226 – 259) 486 (468 – 508) 913 (842 – 1,030) 519

20–39 years 414 (398 – 431) 211 (197 – 223) 405 (387 – 427) 874 (797 – 936) 803

40–59 years 458 (432 – 485) 220 (199 – 236) 447 (419 – 483) 1,040 (900 – 1,180) 658

60 years and older 494 (471 – 519) 210 (199 – 217) 500 (470 – 523) 1,090 (1,030 – 1,320) 902

† Estimate is subject to greater uncertainty due to small cell size.
50 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.5.b. Serum vitamin B12: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in pg/mL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 3 years and older

 1999–2000 487 (481 – 494) 240 (234 – 245) 483 (474 – 494) 993 (970 – 1,040) 7,524

 2001–2002 488 (479 – 497) 236 (232 – 241) 485 (474 – 494) 1,000 (971 – 1,040) 8,390

 2003–2004 489 (472 – 507) 238 (225 – 252) 486 (467 – 500) 1,020 (979 – 1,080) 7,837

 2005–2006 502 (489 – 516) 231 (221 – 242) 497 (482 – 511) 1,100 (1,060 – 1,130) 7,694

Age group

3–5 years

 1999–2000 757 (682 – 839) 441 (321 – 459) 735 (663 – 827) 1,380 (1,300 – 1,730) 361

 2001–2002 804 (773 – 837) 471 (426 – 518) 815 (783 – 836) 1,380 (1,250 – 1,560) 439

 2003–2004 768 (716 – 824) 393 (285 – 422) 775 (716 – 852) 1,550 (1,310 – 1,800) 449

 2005–2006 877 (841 – 913) 482 (437 – 507) 894 (826 – 950) 1,470 (1,430 – 1,660) 444

6–11 years

 1999–2000 695 (659 – 733) 362 (330 – 401) 704 (676 – 738) 1,250 (1,170 – 1,340) 885

 2001–2002 691 (669 – 714) 386 (340 – 412) 696 (672 – 724) 1,270 (1,190 – 1,330) 1,022

 2003–2004 711 (689 – 733) 375 (344 – 419) 714 (679 – 736) 1,240 (1,190 – 1,360) 843

 2005–2006 745 (721 – 769) 418 (381 – 442) 741 (710 – 768) 1,290 (1,230 – 1,370) 904

12–19 years

 1999–2000 501 (491 – 511) 263 (235 – 280) 506 (494 – 518) 954 (905 – 1,010) 2,123

 2001–2002 511 (495 – 528) 269 (256 – 289) 516 (496 – 536) 934 (899 – 983) 2,208

 2003–2004 500 (483 – 518) 267 (255 – 282) 504 (481 – 528) 911 (871 – 949) 2,059

 2005–2006 519 (505 – 534) 273 (269 – 281) 519 (496 – 544) 966 (907 – 1,040) 1,954

20–39 years

 1999–2000 445 (438 – 451) 234 (219 – 240) 448 (432 – 459) 807 (791 – 824) 1,470

 2001–2002 445 (432 – 458) 230 (217 – 239) 445 (432 – 457) 822 (776 – 893) 1,715

 2003–2004 451 (434 – 468) 240 (225 – 253) 449 (431 – 465) 826 (787 – 888) 1,555

 2005–2006 457 (443 – 472) 227 (214 – 239) 452 (440 – 468) 913 (889 – 964) 1,659

40–59 years

 1999–2000 460 (447 – 474) 234 (208 – 256) 447 (432 – 466) 909 (861 – 952) 1,198

 2001–2002 460 (450 – 471) 232 (221 – 238) 456 (443 – 465) 942 (879 – 1,020) 1,478

 2003–2004 460 (435 – 486) 226 (215 – 243) 456 (438 – 479) 957 (833 – 1,110) 1,276

 2005–2006 472 (452 – 493) 223 (195 – 244) 464 (444 – 485) 1,060 (984 – 1,130) 1,353

60 years and older

 1999–2000 482 (467 – 496) 228 (212 – 243) 470 (460 – 483) 1,030 (950 – 1,130) 1,487

 2001–2002 473 (455 – 491) 220 (204 – 231) 479 (465 – 493) 1,000 (962 – 1,030) 1,528

 2003–2004 477 (459 – 496) 208 (198 – 221) 477 (454 – 494) 1,060 (967 – 1,310) 1,655

 2005–2006 487 (466 – 508) 211 (197 – 219) 495 (464 – 511) 1,070 (1,030 – 1,220) 1,380

Gender

Males

 1999–2000 487 (479 – 495) 255 (235 – 264) 488 (478 – 498) 956 (901 – 1,020) 3,682

 2001–2002 490 (476 – 505) 247 (235 – 257) 485 (468 – 497) 963 (919 – 1,010) 4,059

 2003–2004 490 (476 – 505) 250 (229 – 266) 486 (469 – 499) 971 (944 – 1,020) 3,871

 2005–2006 500 (487 – 514) 247 (226 – 259) 497 (482 – 512) 1,040 (987 – 1,110) 3,740

Females

 1999–2000 488 (481 – 495) 233 (222 – 241) 478 (465 – 495) 1,030 (981 – 1,090) 3,842

 2001–2002 486 (476 – 496) 230 (219 – 237) 485 (474 – 495) 1,040 (998 – 1,090) 4,331

 2003–2004 488 (467 – 509) 228 (212 – 245) 486 (463 – 504) 1,080 (1,010 – 1,160) 3,966

 2005–2006 504 (486 – 523) 224 (208 – 236) 497 (476 – 516) 1,150 (1,110 – 1,190) 3,954

Race/ethnicity

Mexican Americans

 1999–2000 551 (523 – 581) 268 (259 – 281) 527 (509 – 542) 1,200 (1,140 – 1,310) 2,571

 2001–2002 516 (491 – 543) 249 (227 – 271) 496 (468 – 535) 1,050 (1,010 – 1,120) 2,124

 2003–2004 543 (513 – 575) 285 (264 – 304) 520 (504 – 538) 1,080 (994 – 1,210) 1,919

 2005–2006 536 (512 – 561) 245 (223 – 257) 515 (487 – 554) 1,180 (1,110 – 1,280) 2,009

Non-Hispanic Blacks

 1999–2000 582 (565 – 599) 286 (261 – 304) 583 (569 – 603) 1,220 (1,150 – 1,270) 1,712

 2001–2002 556 (542 – 570) 269 (250 – 282) 554 (544 – 568) 1,160 (1,100 – 1,220) 2,000

 2003–2004 561 (538 – 585) 281 (262 – 294) 553 (523 – 584) 1,150 (1,090 – 1,310) 2,058

 2005–2006 559 (540 – 579) 256 (231 – 270) 546 (528 – 575) 1,250 (1,200 – 1,340) 2,032

Non-Hispanic Whites

 1999–2000 468 (460 – 476) 235 (231 – 240) 467 (454 – 478) 916 (890 – 951) 2,556

 2001–2002 474 (462 – 485) 233 (227 – 237) 473 (460 – 486) 959 (899 – 1,020) 3,594

 2003–2004 470 (452 – 489) 228 (216 – 244) 469 (449 – 488) 966 (920 – 1,050) 3,272

 2005–2006 487 (470 – 504) 228 (217 – 239) 482 (462 – 502) 1,050 (1,010 – 1,100) 3,062
1. Water-Soluble Vitamins 51

200

300

400

500

600

5th Percentile

Total

(3+y)

99−0001−0203−0405−06

3−5y

99−0001−0203−0405−06

6−11y

99−0001−0203−0405−06

12−19y 99−00 01−02 03−04

05−06

20+y

99−0001−0203−0405−06

Males

99−0001−0203−0405−06

Females 99−00 01−02 03−04

05−06

MA

99−0001−0203−0405−06

NHB

99−0001−0203−0405−06

NHW

99−0001−0203−0405−06

400

600

800

1000

50th Percentile

500

1000

1500

2000

95th Percentile

Figure 1.5.b. Serum vitamin B12: Concentrations by survey cycle

Selected percentiles in pg/mL (95% conence intervals), National Health and 

Nutrition Examination Survey, 1999–2006
52 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.5.c. Serum vitamin B12: Prevalence

Prevalence (in percent) of low serum vitamin B12 concentration (< 200 pg/mL) for the U.S. population 

aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. 

Sample 

size

Prevalence 

(95% conf. interval)

Estimated total 

number of persons

Total, 1 year and older 16,316 2.0 (1.6 – 2.4) 5,563,000

Age group

1–5 years 1,678 § §

6–11 years 1,747 § §

12–19 years 4,013 0.6 (0.4 – 1.0) 210,000

20–39 years 3,214 1.5 (1.2 – 2.0) 1,211,000

40–59 years 2,629 2.6 (1.8 – 3.7) 2,057,000

60 years and older 3,035 3.9 (3.1 – 4.9) 1,815,000

Gender

Males 7,999 1.6 (1.3 – 2.0) 2,165,000

Females 8,317 2.3 (1.9 – 2.9) 3,402,000

Race/ethnicity

Mexican Americans 4,205 1.0 (0.7 – 1.5) 265,000

Non-Hispanic Blacks 4,285 1.2 (0.8 – 1.8) 398,000

Non-Hispanic Whites 6,571 2.2 (1.8 – 2.7) 4,289,000

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
1. Water-Soluble Vitamins 53

Table 1.5.d. Serum vitamin B12: Prevalence by survey cycle

Prevalence (in percent) of low serum vitamin B12 concentration (< 200 pg/mL) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 3 years and older

 1999–2000 7,524 1.9 (1.5 – 2.3) 4,933,000

 2001–2002 8,390 1.8 (1.5 – 2.2) 4,762,000

 2003–2004 7,837 1.6 (1.2 – 2.2) 4,506,000

 2005–2006 7,694 2.4 (1.9 – 3.0) 6,642,000

Age group

3–5 years

 1999–2000 361 § §

 2001–2002 439 § §

 2003–2004 449 § §

 2005–2006 444 § §

6–11 years

 1999–2000 885 § §

 2001–2002 1,022 § §

 2003–2004 843 § §

 2005–2006 904 § §

12–19 years

 1999–2000 2,123 0.8‡ (0.4 – 1.7) 251,000‡

 2001–2002 2,208 0.9 (0.5 – 1.6) 276,000

 2003–2004 2,059 0.6‡ (0.3 – 1.3) 214,000‡

 2005–2006 1,954 0.6‡ (0.3 – 1.2) 209,000‡

20–39 years

 1999–2000 1,470 2.2 (1.4 – 3.3) 1,683,000

 2001–2002 1,715 1.8 (1.2 – 2.8) 1,436,000

 2003–2004 1,555 1.0‡ (0.5 – 2.0) 805,000‡

 2005–2006 1,659 2.0 (1.6 – 2.7) 1,636,000

40–59 years

 1999–2000 1,198 2.4 (1.5 – 4.0) 1,708,000

 2001–2002 1,478 1.8 (1.1 – 3.1) 1,399,000

 2003–2004 1,276 1.9 (1.3 – 2.9) 1,508,000

 2005–2006 1,353 3.3 (1.9 – 5.5) 2,695,000

60 years and older

 1999–2000 1,487 2.7 (1.9 – 3.8) 1,159,000

 2001–2002 1,528 3.6 (2.7 – 4.6) 1,590,000

 2003–2004 1,655 3.9 (2.9 – 5.3) 1,806,000

 2005–2006 1,380 3.9 (2.8 – 5.5) 1,895,000

Gender

Males

 1999–2000 3,682 1.7 (1.2 – 2.4) 2,113,000

 2001–2002 4,059 1.3 (1.0 – 1.8) 1,699,000

 2003–2004 3,871 1.3 (0.9 – 1.9) 1,727,000

 2005–2006 3,740 1.9 (1.4 – 2.5) 2,615,000

Females

 1999–2000 3,842 2.1 (1.7 – 2.6) 2,824,000

 2001–2002 4,331 2.2 (1.7 – 3.0) 3,063,000

 2003–2004 3,966 2.0 (1.4 – 2.8) 2,787,000

 2005–2006 3,954 2.8 (2.0 – 3.9) 4,024,000

Race/ethnicity

Mexican Americans

 1999–2000 2,571 0.8‡ (0.4 – 1.5) 154,000‡

 2001–2002 2,124 1.8 (1.0 – 3.3) 419,000

 2003–2004 1,919 0.7‡ (0.3 – 1.4) 166,000‡

 2005–2006 2,009 1.5 (0.8 – 2.5) 376,000

Non-Hispanic Blacks

 1999–2000 1,712 § §

 2001–2002 2,000 § §

 2003–2004 2,058 0.7‡ (0.3 – 1.6) 239,000‡

 2005–2006 2,032 1.6 (1.0 – 2.6) 551,000

Non-Hispanic Whites

 1999–2000 2,556 2.1 (1.6 – 2.7) 3,858,000

 2001–2002 3,594 2.0 (1.6 – 2.5) 3,733,000

 2003–2004 3,272 1.9 (1.3 – 2.7) 3,572,000

 2005–2006 3,062 2.6 (2.0 – 3.5) 4,978,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
54

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.6.a.1. Plasma total homocysteine: Concentrations

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the total U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 20 years and older 8.21 (8.06 – 8.37) 4.48 (4.35 – 4.57) 5.00 (4.85 – 5.12) 8.04 (7.91 – 8.17) 14.3 (13.9 – 15.0) 17.2 (16.5 – 18.3) 8,999

Age group20–39 years 7.14 (7.04 – 7.24) 3.93 (3.77 – 4.05) 4.44 (4.30 – 4.52) 7.09 (6.99 – 7.22) 11.2 (10.9 – 11.6) 12.4 (12.1 – 13.0) 3,267

40–59 years 8.33 (8.17 – 8.50) 4.84 (4.61 – 5.02) 5.25 (5.15 – 5.36) 8.13 (8.02 – 8.29) 13.9 (13.3 – 14.5) 16.8 (15.8 – 18.3) 2,651

60 years and older 10.1 (9.85 – 10.4) 5.79 (5.56 – 5.99) 6.37 (6.07 – 6.50) 9.79 (9.57 – 10.1) 17.9 (17.1 – 18.9) 21.2 (20.1 – 22.7) 3,081

GenderMales 9.00 (8.83 – 9.18) 5.64 (5.48 – 5.73) 5.96 (5.86 – 6.08) 8.68 (8.56 – 8.84) 14.8 (14.2 – 15.6) 18.0 (16.6 – 19.7) 4,329

Females 7.55 (7.36 – 7.74) 4.12 (3.94 – 4.20) 4.52 (4.40 – 4.69) 7.30 (7.13 – 7.47) 13.8 (13.1 – 14.8) 16.8 (15.8 – 17.9) 4,670

Race/ethnicityMexican Americans 7.09 (6.95 – 7.23) 3.91 (3.76 – 4.01) 4.35 (4.20 – 4.50) 7.02 (6.87 – 7.18) 11.7 (11.2 – 12.2) 12.9 (12.3 – 13.9) 1,814

Non-Hispanic Blacks 8.22 (8.03 – 8.42) 4.42 (4.20 – 4.58) 4.89 (4.61 – 5.05) 8.00 (7.82 – 8.22) 14.8 (14.4 – 15.7) 18.2 (17.0 – 20.0) 1,871

Non-Hispanic Whites 8.39 (8.22 – 8.57) 4.65 (4.43 – 4.85) 5.18 (5.03 – 5.34) 8.21 (8.07 – 8.37) 14.5 (14.0 – 15.2) 17.0 (16.4 – 18.1) 4,670
20−39 40−59 60+ 

0 5 10 15 

Plasma homocysteine (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

15

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 1.6.a. Plasma total homocysteine: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Plasma homocysteine (μmol/L) 0 5 10 Plasma homocysteine (μmol/L) 0 5 10 15 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

1. Water -Soluble Vitamins 55
56 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.6.a.2. Plasma total homocysteine: Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the total U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 20 years and older 8.21 (8.06 – 8.37) 5.00 (4.85 – 5.12) 8.04 (7.91 – 8.17) 14.3 (13.9 – 15.0) 8,999

20–39 years 7.14 (7.04 – 7.24) 4.44 (4.30 – 4.52) 7.09 (6.99 – 7.22) 11.2 (10.9 – 11.6) 3,267

40–59 years 8.33 (8.17 – 8.50) 5.25 (5.15 – 5.36) 8.13 (8.02 – 8.29) 13.9 (13.3 – 14.5) 2,651

60 years and older 10.1 (9.85 – 10.4) 6.37 (6.07 – 6.50) 9.79 (9.57 – 10.1) 17.9 (17.1 – 18.9) 3,081

Males

Total, 20 years and older 9.00 (8.83 – 9.18) 5.96 (5.86 – 6.08) 8.68 (8.56 – 8.84) 14.8 (14.2 – 15.6) 4,329

20–39 years 8.05 (7.90 – 8.20) 5.65 (5.47 – 5.76) 7.94 (7.80 – 8.05) 11.9 (11.5 – 12.5) 1,473

40–59 years 9.21 (8.96 – 9.47) 6.28 (6.15 – 6.43) 8.86 (8.61 – 9.08) 14.3 (13.6 – 15.9) 1,306

60 years and older 10.6 (10.3 – 10.9) 6.89 (6.52 – 7.10) 10.4 (10.0 – 10.8) 18.0 (16.9 – 19.0) 1,550

Females

Total, 20 years and older 7.55 (7.36 – 7.74) 4.52 (4.40 – 4.69) 7.30 (7.13 – 7.47) 13.8 (13.1 – 14.8) 4,670

20–39 years 6.33 (6.21 – 6.46) 3.96 (3.79 – 4.11) 6.31 (6.17 – 6.46) 9.87 (9.47 – 10.5) 1,794

40–59 years 7.58 (7.38 – 7.78) 4.90 (4.67 – 5.07) 7.30 (7.11 – 7.53) 13.0 (12.1 – 15.1) 1,345

60 years and older 9.72 (9.40 – 10.1) 6.02 (5.75 – 6.27) 9.43 (9.05 – 9.69) 17.8 (16.7 – 19.2) 1,531

Table 1.6.a.3. Plasma total homocysteine: Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for Mexican Americans in the 

U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 20 years and older 7.09 (6.95 – 7.23) 4.35 (4.20 – 4.50) 7.02 (6.87 – 7.18) 11.7 (11.2 – 12.2) 1,814

20–39 years 6.61 (6.48 – 6.74) 4.05 (3.88 – 4.31) 6.61 (6.47 – 6.73) 10.6 (9.97 – 11.1) 789

40–59 years 7.36 (7.21 – 7.52) 4.77 (4.38 – 4.92) 7.33 (7.20 – 7.47) 10.9 (10.5 – 12.3) 470

60 years and older 9.55 (9.14 – 9.98) 6.07 (5.48 – 6.41) 9.32 (8.82 – 9.88) 16.0 (15.2 – 18.0) 555

Males

Total, 20 years and older 7.85 (7.70 – 8.01) 5.50 (5.33 – 5.69) 7.74 (7.56 – 7.90) 12.2 (11.6 – 12.6) 866

20–39 years 7.47 (7.30 – 7.64) 5.38 (5.05 – 5.59) 7.38 (7.15 – 7.68) 11.3 (10.9 – 11.9) 353

40–59 years 8.03 (7.80 – 8.26) 5.71 (4.81 – 6.08) 7.91 (7.67 – 8.25) 11.8 (10.7 – 13.4) 239

60 years and older 10.3 (9.78 – 10.8) 6.79 (5.75 – 7.27) 10.0 (9.44 – 10.5) 16.0 (15.1 – 18.4) 274

Females

Total, 20 years and older 6.34 (6.17 – 6.51) 3.91 (3.76 – 4.02) 6.28 (6.10 – 6.50) 10.6 (10.1 – 11.5) 948

20–39 years 5.73 (5.57 – 5.91) 3.67 (3.41 – 3.82) 5.77 (5.57 – 5.99) 8.52 (8.11 – 9.49) 436

40–59 years 6.71 (6.49 – 6.94) 4.39 (3.91 – 4.78) 6.68 (6.36 – 6.86) 10.1 (9.32 – 12.2) 231

60 years and older 8.98 (8.49 – 9.49) 5.67 (4.83 – 6.08) 8.50 (8.07 – 9.07) 15.9 (14.2 – 19.8) 281
1. Water-Soluble Vitamins 57

Table 1.6.a.4. Plasma total homocysteine: Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for non-Hispanic blacks in the 

U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 20 years and older 8.22 (8.03 – 8.42) 4.89 (4.61 – 5.05) 8.00 (7.82 – 8.22) 14.8 (14.4 – 15.7) 1,871

20–39 years 7.14 (6.95 – 7.34) 4.46 (4.20 – 4.61) 7.14 (6.98 – 7.36) 11.2 (10.8 – 11.8) 720

40–59 years 8.55 (8.31 – 8.79) 5.28 (5.10 – 5.39) 8.42 (8.14 – 8.70) 14.7 (13.9 – 17.1) 626

60 years and older 10.7 (10.4 – 11.0) 6.45 (6.00 – 6.95) 10.3 (10.1 – 10.7) 20.7 (18.8 – 23.6) 525

Males

Total, 20 years and older 9.09 (8.91 – 9.27) 5.93 (5.73 – 6.16) 8.78 (8.58 – 8.96) 15.3 (14.5 – 16.4) 896

20–39 years 8.19 (7.95 – 8.44) 5.72 (5.42 – 5.88) 8.04 (7.80 – 8.25) 12.1 (11.6 – 13.1) 340

40–59 years 9.40 (9.12 – 9.70) 6.17 (5.70 – 6.41) 9.11 (8.82 – 9.41) 15.3 (14.2 – 18.2) 292

60 years and older 11.1 (10.7 – 11.6) 6.76 (6.39 – 7.30) 10.9 (10.3 – 11.3) 21.1 (17.5 – 24.9) 264

Females

Total, 20 years and older 7.59 (7.34 – 7.85) 4.52 (4.23 – 4.74) 7.23 (7.07 – 7.53) 14.7 (13.5 – 15.9) 975

20–39 years 6.38 (6.19 – 6.58) 4.19 (3.80 – 4.38) 6.43 (6.25 – 6.72) 9.79 (9.22 – 10.6) 380

40–59 years 7.90 (7.56 – 8.25) 4.98 (4.46 – 5.23) 7.73 (7.22 – 8.08) 13.7 (11.9 – 16.1) 334

60 years and older 10.4 (9.98 – 10.9) 6.15 (5.74 – 6.83) 9.93 (9.50 – 10.5) 20.7 (18.7 – 24.7) 261

Table 1.6.a.5. Plasma total homocysteine: Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for non-Hispanic whites in the 

U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 20 years and older 8.39 (8.22 – 8.57) 5.18 (5.03 – 5.34) 8.21 (8.07 – 8.37) 14.5 (14.0 – 15.2) 4,670

20–39 years 7.26 (7.13 – 7.40) 4.51 (4.33 – 4.79) 7.26 (7.07 – 7.39) 11.2 (10.9 – 11.9) 1,458

40–59 years 8.40 (8.21 – 8.60) 5.36 (5.19 – 5.51) 8.24 (8.09 – 8.44) 13.6 (13.1 – 14.9) 1,353

60 years and older 10.1 (9.82 – 10.4) 6.38 (6.09 – 6.59) 9.82 (9.57 – 10.1) 17.6 (16.7 – 18.4) 1,859

Males

Total, 20 years and older 9.15 (8.94 – 9.36) 6.13 (5.95 – 6.24) 8.80 (8.61 – 8.99) 14.9 (14.2 – 16.0) 2,274

20–39 years 8.11 (7.91 – 8.32) 5.69 (5.47 – 5.85) 8.00 (7.85 – 8.14) 11.8 (11.2 – 12.7) 641

40–59 years 9.28 (8.98 – 9.59) 6.35 (6.21 – 6.55) 8.89 (8.61 – 9.16) 14.2 (13.4 – 16.0) 687

60 years and older 10.6 (10.3 – 10.9) 6.95 (6.65 – 7.15) 10.4 (10.0 – 10.8) 17.8 (16.6 – 19.0) 946

Females

Total, 20 years and older 7.75 (7.54 – 7.96) 4.72 (4.49 – 4.93) 7.53 (7.34 – 7.70) 14.0 (13.3 – 15.2) 2,396

20–39 years 6.50 (6.35 – 6.65) 3.98 (3.77 – 4.13) 6.46 (6.29 – 6.59) 10.2 (9.55 – 11.0) 817

40–59 years 7.63 (7.40 – 7.87) 4.99 (4.70 – 5.18) 7.38 (7.16 – 7.62) 13.0 (11.8 – 15.8) 666

60 years and older 9.69 (9.34 – 10.0) 6.03 (5.71 – 6.28) 9.48 (9.05 – 9.73) 17.1 (16.3 – 18.7) 913
58 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.6.b. Plasma total homocysteine: Concentrations by survey cycle

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 20 years and older

 1999–2000 8.07 (7.95 – 8.18) 4.82 (4.65 – 5.02) 7.94 (7.82 – 8.04) 14.3 (13.5 – 15.0) 4,192

 2001–2002 8.21 (8.04 – 8.38) 5.01 (4.86 – 5.15) 8.01 (7.84 – 8.17) 14.4 (13.9 – 15.1) 4,759

 2003–2004 8.56 (8.32 – 8.81) 5.31 (5.15 – 5.40) 8.33 (8.14 – 8.55) 14.9 (14.2 – 15.9) 4,509

 2005–2006 7.88 (7.73 – 8.04) 4.78 (4.60 – 4.94) 7.76 (7.60 – 7.90) 13.7 (13.1 – 14.5) 4,490

Age group

3–5 years

 1999–2000 4.21 (4.05 – 4.39) 2.81 (2.56 – 2.98) 4.19 (4.02 – 4.42) 6.31 (5.75 – 7.70) 376

 2001–2002 4.31 (4.16 – 4.46) 2.95 (2.65 – 3.21) 4.28 (4.20 – 4.44) 6.15 (5.89 – 6.50) 454

 2003–2004 4.36 (4.18 – 4.55) 3.10 (2.87 – 3.19) 4.42 (4.14 – 4.65) 6.28 (5.72 – 6.66) 454

6–11 years

 1999–2000 4.35 (4.18 – 4.54) 2.91 (2.55 – 3.09) 4.36 (4.20 – 4.50) 6.49 (6.21 – 6.78) 899

 2001–2002 4.67 (4.58 – 4.77) 3.27 (3.04 – 3.44) 4.61 (4.53 – 4.73) 6.94 (6.60 – 7.21) 1,034

 2003–2004 4.65 (4.53 – 4.78) 3.22 (2.99 – 3.37) 4.68 (4.51 – 4.82) 6.62 (6.44 – 6.77) 852

12–19 years

 1999–2000 5.87 (5.70 – 6.05) 3.65 (3.37 – 3.81) 5.83 (5.70 – 6.01) 9.58 (9.23 – 10.6) 2,132

 2001–2002 6.03 (5.88 – 6.19) 3.96 (3.64 – 4.14) 5.90 (5.73 – 6.11) 9.48 (9.30 – 10.1) 2,225

 2003–2004 6.30 (6.14 – 6.47) 4.26 (4.08 – 4.36) 6.21 (6.02 – 6.43) 10.0 (9.43 – 10.7) 2,073

20–39 years

 1999–2000 7.19 (7.04 – 7.35) 4.23 (4.06 – 4.42) 7.26 (7.03 – 7.43) 11.9 (11.3 – 12.5) 1,474

 2001–2002 7.27 (7.12 – 7.42) 4.42 (4.21 – 4.67) 7.16 (7.08 – 7.25) 12.0 (11.6 – 12.8) 1,720

 2003–2004 7.47 (7.33 – 7.62) 4.71 (4.47 – 4.99) 7.42 (7.30 – 7.58) 11.3 (11.0 – 12.0) 1,561

 2005–2006 6.81 (6.67 – 6.95) 4.21 (3.99 – 4.42) 6.72 (6.61 – 6.84) 11.0 (10.4 – 11.5) 1,706

40–59 years

 1999–2000 8.27 (8.07 – 8.48) 5.18 (5.05 – 5.27) 8.08 (7.94 – 8.26) 13.5 (12.4 – 15.6) 1,209

 2001–2002 8.30 (8.17 – 8.43) 5.35 (5.16 – 5.48) 8.17 (8.02 – 8.31) 13.4 (12.7 – 14.1) 1,494

 2003–2004 8.67 (8.42 – 8.93) 5.60 (5.33 – 5.74) 8.44 (8.20 – 8.61) 14.4 (13.6 – 16.2) 1,280

 2005–2006 8.01 (7.84 – 8.18) 5.13 (4.82 – 5.25) 7.90 (7.70 – 8.07) 12.8 (12.5 – 14.1) 1,371

60 years and older

 1999–2000 9.78 (9.53 – 10.0) 6.10 (6.03 – 6.17) 9.45 (9.23 – 9.75) 17.6 (16.9 – 18.7) 1,509

 2001–2002 10.2 (9.76 – 10.6) 6.36 (6.12 – 6.64) 9.79 (9.33 – 10.2) 18.6 (17.7 – 19.6) 1,545

 2003–2004 10.6 (10.2 – 10.9) 6.62 (6.33 – 6.99) 10.3 (9.93 – 10.6) 19.0 (17.6 – 20.2) 1,668

 2005–2006 9.69 (9.36 – 10.0) 6.01 (5.75 – 6.29) 9.40 (9.05 – 9.75) 17.5 (16.2 – 18.5) 1,413

Gender

(20 years and older)

Males

 1999–2000 8.90 (8.69 – 9.11) 5.77 (5.57 – 5.92) 8.65 (8.42 – 8.92) 15.0 (14.2 – 16.6) 1,959

 2001–2002 9.06 (8.89 – 9.23) 6.08 (5.86 – 6.24) 8.74 (8.53 – 8.96) 14.9 (14.3 – 15.8) 2,255

 2003–2004 9.35 (9.06 – 9.65) 6.28 (6.09 – 6.42) 8.92 (8.67 – 9.17) 15.3 (14.5 – 16.7) 2,177

 2005–2006 8.67 (8.49 – 8.84) 5.82 (5.70 – 5.92) 8.42 (8.25 – 8.59) 14.2 (13.2 – 15.2) 2,152

Females

 1999–2000 7.37 (7.23 – 7.52) 4.31 (4.07 – 4.53) 7.30 (7.14 – 7.42) 13.1 (12.7 – 14.3) 2,233

 2001–2002 7.50 (7.32 – 7.68) 4.53 (4.32 – 4.73) 7.23 (7.06 – 7.36) 13.6 (12.9 – 14.8) 2,504

 2003–2004 7.89 (7.61 – 8.18) 4.86 (4.51 – 5.03) 7.60 (7.39 – 7.87) 14.3 (13.4 – 15.8) 2,332

 2005–2006 7.22 (7.00 – 7.45) 4.40 (4.19 – 4.51) 6.98 (6.80 – 7.15) 13.1 (12.1 – 14.9) 2,338

Race/ethnicity

(20 years and older)

Mexican Americans

 1999–2000 7.28 (7.06 – 7.50) 4.22 (3.96 – 4.58) 7.08 (6.88 – 7.36) 12.5 (11.8 – 13.9) 1,146

 2001–2002 7.18 (6.85 – 7.53) 4.27 (4.00 – 4.47) 7.10 (6.80 – 7.34) 12.4 (11.8 – 13.7) 1,009

 2003–2004 7.30 (7.11 – 7.49) 4.49 (4.25 – 4.57) 7.31 (7.17 – 7.42) 11.9 (11.3 – 12.7) 904

 2005–2006 6.90 (6.74 – 7.05) 4.31 (3.99 – 4.44) 6.75 (6.62 – 6.94) 11.2 (10.8 – 12.2) 910

Non-Hispanic Blacks

 1999–2000 8.14 (7.87 – 8.41) 4.71 (4.25 – 4.87) 7.91 (7.51 – 8.34) 15.3 (14.7 – 16.6) 773

 2001–2002 8.29 (8.03 – 8.55) 4.64 (4.40 – 5.08) 7.93 (7.72 – 8.17) 15.4 (14.4 – 17.9) 872

 2003–2004 8.53 (8.24 – 8.83) 5.04 (4.84 – 5.24) 8.29 (7.99 – 8.59) 14.9 (14.4 – 16.6) 869

 2005–2006 7.94 (7.72 – 8.17) 4.73 (4.50 – 4.90) 7.74 (7.50 – 7.95) 14.7 (14.0 – 15.5) 1,002

Non-Hispanic Whites

 1999–2000 8.19 (8.07 – 8.30) 5.09 (4.82 – 5.19) 8.03 (7.93 – 8.22) 14.3 (13.5 – 14.8) 1,874

 2001–2002 8.37 (8.21 – 8.54) 5.18 (5.04 – 5.26) 8.14 (7.98 – 8.28) 14.6 (14.0 – 15.7) 2,514

 2003–2004 8.74 (8.50 – 8.99) 5.46 (5.37 – 5.57) 8.53 (8.29 – 8.72) 15.1 (14.2 – 16.1) 2,406

 2005–2006 8.06 (7.89 – 8.24) 4.97 (4.70 – 5.15) 7.94 (7.83 – 8.04) 13.9 (13.2 – 14.8) 2,264
59

2

3

4

5

6

7

5th Percentile

Total

(20+y)

99−0001−0203−0405−06

1−5y

99−0001−0203−0405−06

6−11y

99−0001−0203−0405−06

12−19y 99−00 01−02 03−04

05−06

20+y

99−0001−0203−0405−06

Males

(20+y)

99−0001−0203−0405−06

Females

(20+y)

99−0001−0203−0405−06

MA

(20+y)

99−0001−0203−0405−06

NHB

(20+y)

99−0001−0203−0405−06

NHW

(20+y)

99−0001−0203−0405−06

4

6

8

10

50th Percentile

5

10

15

20

95th Percentile

Figure 1.6.b. Plasma total homocysteine: Concentrations by survey cycle

Selected percentiles in μmol/L (95% con dence intervals), National Health and 

Nutrition Examination Survey, 1999–2006
60 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.6.c. Plasma total homocysteine: Prevalence

Prevalence (in percent) of high Plasma total homocysteine concentration (> 13 μmol/L) for the U.S. 

population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Sample

size

Prevalence 

(95% conf. interval)

Estimated total 

number of persons

Total, 20 years and older 8,999 7.7 (6.8 – 8.8) 15,825,000

Age group

20–39 years 3,267 1.9 (1.4 – 2.4) 1,482,000

40–59 years 2,651 7.0 (5.6 – 8.7) 5,553,000

60 years and older 3,081 18.5 (16.3 – 21.0) 8,620,000

Gender

Males 4,329 9.2 (7.9 – 10.6) 9,021,000

Females 4,670 6.4 (5.2 – 7.7) 6,796,000

Race/ethnicity

Mexican Americans 1,814 2.1 (1.5 – 2.9) 336,000

Non-Hispanic Blacks 1,871 8.9 (7.7 – 10.2) 2,005,000

Non-Hispanic Whites 4,670 8.3 (7.1 – 9.6) 12,066,000
1. Water-Soluble Vitamins 61

Table 1.6.d. Plasma total homocysteine: Prevalence by survey cycle

Prevalence (in percent) of high Plasma total homocysteine concentration (> 13 μmol/L) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006.

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 20 years and older

 1999–2000 4,192 6.9 (6.0 – 8.1) 13,319,000

 2001–2002 4,759 7.8 (6.5 – 9.2) 15,479,000

 2003–2004 4,509 9.5 (7.9 – 11.3) 19,421,000

 2005–2006 4,490 6.0 (5.1 – 6.9) 12,553,000

Age group

3–5 years

 1999–2000 376 § §

 2001–2002 454 § §

 2003–2004 454 § §

6–11 years

 1999–2000 899 § §

 2001–2002 1,034 § §

 2003–2004 852 § §

12–19 years

 1999–2000 2,132 1.5‡ (0.8 – 2.8) 466,000‡

 2001–2002 2,225 0.9 (0.5 – 1.6) 294,000

 2003–2004 2,073 1.1‡ (0.5 – 2.1) 358,000‡

20–39 years

 1999–2000 1,474 2.6 (1.6 – 4.3) 2,058,000

 2001–2002 1,720 3.2 (2.2 – 4.6) 2,505,000

 2003–2004 1,561 2.4 (1.7 – 3.4) 1,923,000

 2005–2006 1,706 1.3 (0.8 – 2.2) 1,034,000

40–59 years

 1999–2000 1,209 5.9 (4.3 – 8.1) 4,188,000

 2001–2002 1,494 5.8 (4.4 – 7.5) 4,378,000

 2003–2004 1,280 9.4 (7.0 – 12.4) 7,396,000

 2005–2006 1,371 4.7 (3.6 – 6.2) 3,894,000

60 years and older

 1999–2000 1,509 17.3 (14.8 – 20.3) 7,441,000

 2001–2002 1,545 20.5 (17.1 – 24.5) 9,180,000

 2003–2004 1,668 21.6 (19.2 – 24.2) 10,039,000

 2005–2006 1,413 15.6 (12.3 – 19.5) 7,527,000

Gender

(20 years and older)

Males

 1999–2000 1,959 8.6 (7.0 – 10.4) 7,854,000

 2001–2002 2,255 9.6 (7.8 – 11.7) 9,136,000

 2003–2004 2,177 11.4 (9.4 – 13.7) 11,197,000

 2005–2006 2,152 7.0 (5.6 – 8.7) 7,036,000

Females

 1999–2000 2,233 5.4 (4.5 – 6.6) 5,459,000

 2001–2002 2,504 6.1 (4.9 – 7.5) 6,342,000

 2003–2004 2,332 7.7 (6.0 – 9.8) 8,202,000

 2005–2006 2,338 5.1 (3.8 – 6.8) 5,525,000

Race/ethnicity

(20 years and older)

Mexican Americans

 1999–2000 1,146 4.4 (3.3 – 5.9) 542,000

 2001–2002 1,009 3.8 (2.5 – 5.5) 542,000

 2003–2004 904 2.7 (1.8 – 4.0) 426,000

 2005–2006 910 1.6 (1.0 – 2.5) 263,000

Non-Hispanic Blacks

 1999–2000 773 8.6 (6.7 – 10.8) 1,872,000

 2001–2002 872 9.6 (7.8 – 11.8) 2,120,000

 2003–2004 869 10.8 (8.7 – 13.2) 2,435,000

 2005–2006 1,002 7.0 (6.0 – 8.2) 1,640,000

Non-Hispanic Whites

 1999–2000 1,874 7.0 (6.0 – 8.1) 9,938,000

 2001–2002 2,514 8.4 (6.9 – 10.3) 12,142,000

 2003–2004 2,406 10.1 (8.3 – 12.2) 14,718,000

 2005–2006 2,264 6.5 (5.4 – 7.7) 9,541,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
62

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.7.a.1. Plasma methylmalonic acid: Concentrations

Geometric mean and selected percentiles of plasma concentrations (in nmol/L) for the total U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 3 years and older 134 (128 – 140) 63.2 (60.5 – 65.6) 70.0 (67.3 – 72.8) 127 (122 – 132) 293 (277 – 320) 387 (359 – 428) 7,544

Age group3–5 years 120 (110 – 130) 61.1† (54.6 – 63.4) 65.2 (56.6 – 72.1) 117 (109 – 124) 269 (235 – 307) 299† (271 – 516) 421

6–11 years 117 (111 – 123) 60.6 (56.9 – 64.4) 67.5 (61.0 – 72.6) 113 (109 – 118) 228 (204 – 253) 258 (229 – 461) 806

12–19 years 118 (115 – 122) 62.4 (56.8 – 64.4) 67.3 (64.8 – 70.0) 115 (110 – 118) 222 (210 – 263) 280 (247 – 326) 1,979

20–39 years 122 (116 – 127) 61.4 (57.0 – 64.4) 67.3 (64.2 – 69.6) 116 (110 – 123) 246 (231 – 275) 303 (279 – 368) 1,496

40–59 years 137 (129 – 144) 62.9 (59.2 – 67.8) 70.9 (66.6 – 75.0) 130 (124 – 138) 275 (252 – 338) 387 (324 – 572) 1,230

60 years and older 177 (169 – 186) 79.7 (73.5 – 83.6) 89.9 (83.6 – 94.5) 163 (156 – 170) 429 (392 – 482) 628 (536 – 822) 1,612

GenderMales 136 (130 – 142) 65.0 (63.0 – 67.9) 72.4 (69.4 – 75.4) 127 (123 – 132) 299 (277 – 339) 406 (364 – 526) 3,719

Females 131 (125 – 138) 61.3 (58.2 – 63.9) 68.1 (65.2 – 71.3) 126 (120 – 132) 287 (272 – 315) 362 (328 – 403) 3,825

Race/ethnicityMexican Americans 111 (108 – 114) 56.2 (53.3 – 58.0) 61.9 (58.6 – 64.4) 106 (100 – 112) 230 (209 – 254) 300 (248 – 387) 1,834

Non-Hispanic Blacks 109 (104 – 114) 55.3 (52.3 – 57.9) 61.1 (57.7 – 64.1) 105 (99.3 – 111) 224 (206 – 246) 270 (249 – 298) 1,993

Non-Hispanic Whites 143 (136 – 150) 69.4 (65.1 – 72.9) 76.9 (73.1 – 79.9) 135 (129 – 141) 308 (283 – 340) 393 (360 – 480) 3,152

† Estimate is subject to greater uncertainty due to small cell size.
3−5 6−11 12−19 20−39 40−59 60+ 

0 50 100 150 200

Plasma methylmalonic acid (nmol/L) 

Overall 

3−5 6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

00 

Non−Hispanic Blacks 

d 

Non−Hispanic Whites 

Figure 1.7.a. Plasma methylmalonic acid: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma methylmalonic acid Plasma methylmalonic aci (nmol/L) (nmol/L) 0 50 100 150 200 0 50 100 150 2 

3−5 6−11 12−19 20−39 40−59 60+ 3−5 6−11 12−19 20−39 40−59 60+ 

Females Males 

3−5 6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

3−5 6−11 12−19 20−39 40−59 60+ 

1. Water -Soluble Vitamins 63
64 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.7.a.2. Plasma methylmalonic acid: Total population

Geometric mean and selected percentiles of plasma concentrations (in nmol/L) for the total U.S. population 

aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 134 (128 – 140) 79.6 (76.4 – 82.4) 127 (122 – 132) 231 (218 – 249) 7,544

3–5 years 120 (110 – 130) 74.5 (67.8 – 79.0) 117 (109 – 124) 198 (169 – 269) 421

6–11 years 117 (111 – 123) 77.6 (72.5 – 79.9) 113 (109 – 118) 184 (168 – 205) 806

12–19 years 118 (115 – 122) 75.1 (72.5 – 78.2) 115 (110 – 118) 189 (179 – 201) 1,979

20–39 years 122 (116 – 127) 75.5 (71.7 – 79.2) 116 (110 – 123) 201 (188 – 219) 1,496

40–59 years 137 (129 – 144) 82.3 (77.2 – 86.3) 130 (124 – 138) 223 (209 – 238) 1,230

60 years and older 177 (169 – 186) 102 (96.8 – 106) 163 (156 – 170) 328 (312 – 358) 1,612

Males

Total, 3 years and older 136 (130 – 142) 82.8 (79.4 – 85.3) 127 (123 – 132) 231 (217 – 253) 3,719

3–5 years 122 (110 – 135) 71.6 (65.1 – 78.7) 118 (103 – 129) 239 (180 – 272) 223

6–11 years 117 (109 – 126) 75.9 (69.5 – 79.4) 112 (107 – 119) 191 (167 – 223) 385

12–19 years 123 (118 – 129) 79.2 (76.7 – 81.4) 119 (112 – 125) 197 (179 – 210) 1,016

20–39 years 126 (120 – 133) 78.7 (72.6 – 85.9) 119 (111 – 125) 209 (194 – 223) 705

40–59 years 141 (132 – 151) 86.2 (79.9 – 93.2) 134 (128 – 141) 224 (206 – 266) 608

60 years and older 178 (168 – 189) 99.0 (93.0 – 103) 162 (155 – 174) 351 (328 – 373) 782

Females

Total, 3 years and older 131 (125 – 138) 77.5 (73.7 – 81.0) 126 (120 – 132) 231 (217 – 250) 3,825

3–5 years 117 (107 – 127) 75.5 (65.7 – 79.7) 117 (109 – 122) 169 (155 – 276) 198

6–11 years 116 (111 – 122) 78.7 (73.9 – 81.4) 115 (109 – 119) 177 (164 – 207) 421

12–19 years 113 (110 – 116) 71.4 (67.8 – 74.1) 109 (106 – 113) 181 (171 – 203) 963

20–39 years 117 (112 – 123) 73.0 (68.4 – 76.5) 113 (106 – 120) 197 (180 – 218) 791

40–59 years 132 (123 – 142) 79.0 (71.2 – 85.3) 126 (119 – 136) 222 (208 – 236) 622

60 years and older 177 (165 – 189) 106 (97.3 – 111) 164 (155 – 170) 315 (291 – 357) 830

Table 1.7.a.3. Plasma methylmalonic acid: Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in nmol/L) for Mexican Americans in the 

U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 111 (108 – 114) 69.4 (67.1 – 72.4) 106 (100 – 112) 186 (174 – 201) 1,834

3–5 years 107 (94.2 – 122) 74.1† (65.1 – 76.9) 106 (87.8 – 118) 150† (133 – 279) 111

6–11 years 105 (96.7 – 113) 70.8 (61.5 – 77.1) 101 (92.6 – 112) 152 (142 – 192) 258

12–19 years 107 (102 – 112) 65.8 (62.4 – 69.8) 104 (98.3 – 109) 167 (160 – 184) 599

20–39 years 108 (99.2 – 117) 67.7 (65.0 – 70.6) 103 (92.6 – 116) 181 (156 – 242) 322

40–59 years 115 (110 – 119) 71.7 (65.4 – 75.8) 108 (102 – 115) 201 (178 – 220) 216

60 years and older 152 (138 – 168) 87.6 (81.1 – 92.8) 138 (125 – 159) 272 (245 – 368) 328

Males

Total, 3 years and older 116 (114 – 119) 74.3 (69.8 – 77.3) 109 (106 – 114) 199 (185 – 217) 911

3–5 years 108 (93.9 – 124) 72.6† (57.0 – 81.5) 105 (87.6 – 119) 145† (131 – 307) 59

6–11 years 104 (96.1 – 113) 70.2 (50.9 – 79.4) 105 (90.5 – 113) 148 (138 – 232) 124

12–19 years 118 (111 – 126) 72.9 (67.6 – 78.7) 111 (104 – 119) 198 (171 – 242) 306

20–39 years 113 (104 – 124) 75.6 (64.0 – 81.1) 106 (99.5 – 113) 189 (157 – 363) 149

40–59 years 123 (114 – 133) 73.4 (65.2 – 76.6) 116 (103 – 131) 218 (173 – 330) 113

60 years and older 153 (130 – 181) 89.1 (80.1 – 95.3) 137 (119 – 158) 268 (234 – 411) 160

Females

Total, 3 years and older 105 (99.3 – 112) 67.0 (61.7 – 68.7) 102 (92.6 – 110) 176 (157 – 201) 923

3–5 years 106 (87.6 – 128) 74.1† (57.0 – 81.0) 105 (80.4 – 127) 152† (124 – 228) 52

6–11 years 105 (94.3 – 117) 72.4 (58.9 – 77.7) 99.7 (89.6 – 115) 160 (145 – 218) 134

12–19 years 96.2 (91.3 – 101) 61.6 (55.1 – 66.5) 95.5 (90.0 – 102) 150 (142 – 156) 293

20–39 years 102 (91.2 – 113) 65.4 (56.5 – 68.0) 99.5 (81.5 – 119) 170 (147 – 208) 173

40–59 years 106 (95.2 – 117) 69.8† (58.0 – 75.4) 101 (95.6 – 109) 181† (137 – 247) 103

60 years and older 151 (135 – 170) 83.4 (77.3 – 96.5) 140 (120 – 171) 279 (243 – 333) 168

† Estimate is subject to greater uncertainty due to small cell size.
1. Water-Soluble Vitamins 65

Table 1.7.a.4. Plasma methylmalonic acid: Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in nmol/L) for non-Hispanic blacks in the 

U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample

10th 50th 90th size

Males and Females

Total, 3 years and older 109 (104 – 114) 68.4 (65.1 – 71.0) 105 (99.3 – 111) 177 (167 – 188) 1,993

3–5 years 95.4 (87.4 – 104) 62.7 (54.6 – 72.2) 99.4 (86.5 – 106) 139 (125 – 159) 146

6–11 years 98.7 (92.9 – 105) 65.9 (56.1 – 71.0) 96.6 (92.1 – 103) 147 (139 – 159) 290

12–19 years 96.0 (90.6 – 102) 63.9 (60.0 – 66.4) 93.2 (89.7 – 97.7) 147 (135 – 160) 721

20–39 years 102 (96.5 – 108) 66.7 (56.2 – 70.0) 99.3 (91.3 – 107) 161 (151 – 177) 328

40–59 years 117 (108 – 126) 74.1 (63.5 – 78.1) 114 (99.8 – 122) 193 (161 – 246) 275

60 years and older 148 (137 – 159) 91.8 (76.6 – 105) 142 (131 – 147) 245 (217 – 299) 233

Males

Total, 3 years and older 112 (107 – 117) 69.6 (67.8 – 72.6) 108 (101 – 113) 184 (171 – 199) 992

3–5 years 95.4 (87.4 – 104) 65.2† (< LOD – 73.4) 101 (87.6 – 107) 125† (121 – 140) 76

6–11 years 99.0 (90.5 – 108) 64.3 (50.7 – 69.3) 97.4 (86.2 – 109) 150 (138 – 177) 135

12–19 years 102 (95.5 – 109) 69.5 (64.4 – 72.8) 97.9 (92.3 – 103) 154 (143 – 179) 381

20–39 years 107 (99.9 – 114) 69.3 (64.1 – 72.9) 102 (97.0 – 114) 157 (149 – 182) 161

40–59 years 122 (110 – 136) 71.5 (61.4 – 77.4) 117 (104 – 124) 226 (179 – 280) 130

60 years and older 145 (133 – 158) 85.0† (77.2 – 98.7) 138 (125 – 150) 237† (212 – 322) 109

Females

Total, 3 years and older 107 (100 – 114) 66.9 (62.2 – 70.8) 104 (95.7 – 110) 172 (161 – 187) 1,001

3–5 years 95.4 (84.0 – 108) 59.3† (< LOD – 71.8) 95.6 (80.0 – 108) 141† (126 – 268) 70

6–11 years 98.4 (92.6 – 105) 68.7 (57.1 – 74.3) 95.9 (89.5 – 105) 145 (135 – 155) 155

12–19 years 90.3 (84.7 – 96.2) 59.4 (56.1 – 64.1) 89.6 (85.8 – 94.5) 139 (128 – 151) 340

20–39 years 98.5 (91.3 – 106) 64.5 (52.6 – 68.2) 92.9 (85.7 – 101) 162 (142 – 197) 167

40–59 years 113 (104 – 123) 75.0 (62.0 – 82.2) 110 (97.7 – 120) 169 (151 – 211) 145

60 years and older 150 (137 – 163) 96.5 (72.9 – 107) 143 (129 – 152) 247 (216 – 334) 124

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.

Table 1.7.a.5. Plasma methylmalonic acid: Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in nmol/L) for non-Hispanic whites in the 

U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample

10th 50th 90th size

Males and Females

Total, 3 years and older 143 (136 – 150) 86.7 (82.8 – 89.9) 135 (129 – 141) 242 (229 – 266) 3,152

3–5 years 133 (123 – 145) 80.5 (64.1 – 94.6) 128 (119 – 140) 246 (200 – 274) 115

6–11 years 130 (122 – 139) 87.3 (77.5 – 95.7) 122 (114 – 135) 213 (189 – 232) 196

12–19 years 128 (122 – 133) 79.9 (77.7 – 83.3) 122 (119 – 127) 203 (188 – 217) 525

20–39 years 128 (121 – 136) 82.7 (76.3 – 87.1) 123 (115 – 132) 204 (194 – 228) 708

40–59 years 142 (134 – 152) 86.6 (80.6 – 92.9) 136 (128 – 145) 227 (210 – 258) 642

60 years and older 182 (173 – 192) 105 (99.1 – 109) 167 (161 – 176) 341 (316 – 365) 966

Males

Total, 3 years and older 144 (137 – 152) 91.0 (85.8 – 94.2) 134 (127 – 142) 240 (224 – 274) 1,535

3–5 years 139 (121 – 160) 73.7† (63.0 – 99.4) 130 (118 – 155) 267† (242 – 279) 62

6–11 years 132 (120 – 146) 91.6† (72.1 – 101) 120 (111 – 141) 207† (184 – 266) 91

12–19 years 131 (122 – 141) 83.4 (78.2 – 89.6) 125 (119 – 133) 204 (179 – 256) 266

20–39 years 130 (120 – 141) 88.1 (69.7 – 93.3) 123 (113 – 137) 205 (186 – 231) 319

40–59 years 145 (135 – 157) 95.7 (82.6 – 99.6) 138 (130 – 145) 224 (203 – 275) 321

60 years and older 182 (171 – 195) 101 (95.8 – 104) 168 (159 – 187) 364 (330 – 390) 476

Females

Total, 3 years and older 141 (135 – 148) 84.1 (79.2 – 88.1) 135 (129 – 141) 246 (231 – 261) 1,617

3–5 years 126 (113 – 141) 80.7† (54.0 – 103) 122 (113 – 140) 168† (151 – 311) 53

6–11 years 128 (121 – 136) 86.5† (71.3 – 92.4) 122 (116 – 129) 209† (170 – 251) 105

12–19 years 124 (119 – 129) 77.6 (73.9 – 80.2) 119 (115 – 127) 202 (179 – 231) 259

20–39 years 126 (119 – 133) 80.0 (75.3 – 84.5) 121 (114 – 132) 203 (187 – 239) 389

40–59 years 140 (128 – 152) 82.8 (71.4 – 90.2) 135 (122 – 147) 231 (219 – 259) 321

60 years and older 183 (170 – 196) 109 (103 – 116) 166 (161 – 175) 318 (299 – 360) 490

† Estimate is subject to greater uncertainty due to small cell size.
66 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.7.b. Plasma methylmalonic acid: Concentrations by survey cycle

Geometric mean and selected percentiles of plasma concentrations (in nmol/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample

5th 50th 95th size

Total, 3 years and older

 1999–2000 132 (129 – 136) 64.9 (62.8 – 67.0) 123 (119 – 126) 280 (266 – 298) 7,597

 2001–2002 130 (126 – 133) 63.8 (61.3 – 66.4) 119 (116 – 123) 276 (263 – 293) 8,451

 2003–2004 134 (128 – 140) 70.0 (67.3 – 72.8) 127 (122 – 132) 293 (277 – 320) 7,544

Age group

3–5 years

 1999–2000 124 (118 – 131) 67.4 (61.8 – 71.6) 116 (111 – 122) 237 (197 – 332) 376

 2001–2002 116 (112 – 121) 63.9 (61.8 – 66.0) 108 (104 – 113) 219 (195 – 244) 453

 2003–2004 120 (110 – 130) 65.2 (56.6 – 72.1) 117 (109 – 124) 269 (235 – 307) 421

6–11 years

 1999–2000 125 (117 – 134) 66.9 (63.5 – 70.3) 117 (107 – 130) 210 (191 – 319) 898

 2001–2002 118 (114 – 122) 62.6 (57.7 – 66.8) 113 (109 – 118) 200 (187 – 224) 1,031

 2003–2004 117 (111 – 123) 67.5 (61.0 – 72.6) 113 (109 – 118) 228 (204 – 253) 806

12–19 years

 1999–2000 118 (112 – 125) 60.2 (55.1 – 63.5) 109 (103 – 117) 231 (206 – 291) 2,132

 2001–2002 115 (112 – 119) 56.9 (54.6 – 59.1) 107 (104 – 110) 228 (216 – 264) 2,220

 2003–2004 118 (115 – 122) 67.3 (64.8 – 70.0) 115 (110 – 118) 222 (210 – 263) 1,979

20–39 years

 1999–2000 124 (119 – 129) 62.4 (59.7 – 64.9) 116 (110 – 121) 259 (235 – 295) 1,474

 2001–2002 121 (116 – 125) 59.5 (55.9 – 61.8) 112 (107 – 117) 239 (226 – 268) 1,715

 2003–2004 122 (116 – 127) 67.3 (64.2 – 69.6) 116 (110 – 123) 246 (231 – 275) 1,496

40–59 years

 1999–2000 133 (130 – 137) 65.4 (62.6 – 68.1) 124 (122 – 127) 251 (239 – 277) 1,210

 2001–2002 131 (127 – 135) 71.2 (66.4 – 73.4) 120 (117 – 124) 264 (231 – 302) 1,491

 2003–2004 137 (129 – 144) 70.9 (66.6 – 75.0) 130 (124 – 138) 275 (252 – 338) 1,230

60 years and older

 1999–2000 168 (163 – 174) 80.3 (67.7 – 89.1) 149 (145 – 155) 423 (392 – 458) 1,507

 2001–2002 172 (164 – 180) 76.9 (74.1 – 79.8) 156 (150 – 162) 487 (413 – 604) 1,541

 2003–2004 177 (169 – 186) 89.9 (83.6 – 94.5) 163 (156 – 170) 429 (392 – 482) 1,612

Gender

Males

 1999–2000 136 (132 – 141) 67.2 (64.5 – 70.0) 127 (123 – 131) 288 (265 – 309) 3,708

 2001–2002 133 (129 – 138) 66.4 (62.7 – 70.1) 123 (120 – 127) 273 (258 – 294) 4,091

 2003–2004 136 (130 – 142) 72.4 (69.4 – 75.4) 127 (123 – 132) 299 (277 – 339) 3,719

Females

 1999–2000 128 (124 – 132) 63.3 (61.1 – 65.5) 118 (114 – 122) 276 (262 – 294) 3,889

 2001–2002 126 (123 – 130) 62.3 (59.9 – 64.7) 115 (111 – 119) 277 (261 – 301) 4,360

 2003–2004 131 (125 – 138) 68.1 (65.2 – 71.3) 126 (120 – 132) 287 (272 – 315) 3,825

Race/ethnicity

Mexican Americans

 1999–2000 110 (106 – 114) 56.2 (54.9 – 57.5) 100 (97.3 – 103) 225 (198 – 270) 2,595

 2001–2002 111 (107 – 115) 53.7 (51.0 – 56.5) 103 (99.0 – 108) 225 (218 – 235) 2,131

 2003–2004 111 (108 – 114) 61.9 (58.6 – 64.4) 106 (100 – 112) 230 (209 – 254) 1,834

Non-Hispanic Blacks

 1999–2000 108 (103 – 113) 57.5 (52.6 – 60.7) 98.3 (91.5 – 105) 217 (192 – 250) 1,732

 2001–2002 112 (108 – 116) 55.6 (53.0 – 58.2) 102 (98.3 – 107) 220 (200 – 258) 2,036

 2003–2004 109 (104 – 114) 61.1 (57.7 – 64.1) 105 (99.3 – 111) 224 (206 – 246) 1,993

Non-Hispanic Whites

 1999–2000 140 (136 – 144) 72.0 (69.8 – 74.2) 131 (126 – 135) 290 (272 – 311) 2,573

 2001–2002 137 (133 – 141) 70.6 (66.8 – 72.7) 126 (122 – 130) 288 (272 – 304) 3,605

 2003–2004 143 (136 – 150) 76.9 (73.1 – 79.9) 135 (129 – 141) 308 (283 – 340) 3,152
1. Water-Soluble Vitamins 67

50

60

70

80

5th Percentile

Total

(3+y)

99−0001−0203−04

3−5y

99−0001−0203−04

6−11y

99−0001−0203−04

12−19y 99−00 01−02 03−0420+y

99−0001−0203−04

Males

99−0001−0203−04

Females 99−00 01−02 03−04MA

99−0001−0203−04

NHB

99−0001−0203−04

NHW

99−0001−0203−04

80

100

120

140

160

50th Percentile

150

200

250

300

350

95th Percentile

Figure 1.7.b. Plasma methylmalonic acid: Concentrations by survey cycle

Selected percentiles in nmol/L (95% condence intervals), National Health and 

Nutrition Examination Survey, 1999–2004
68 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.7.c. Plasma methylmalonic acid: Prevalence

Prevalence (in percent) of high plasma methylmalonic acid concentration (> 271 nmol/L) for the U.S. 

population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Sample 

size

Prevalence 

(95% conf. interval)

Estimated total 

number of persons

Total, 3 years and older 7,544 6.5 (5.3 – 7.9) 18,411,000

Age group

3–5 years 421 4.5‡ (2.0 – 9.7) 916,000‡

6–11 years 806 § §

12–19 years 1,979 3.2 (2.2 – 4.6) 1,054,000

20–39 years 1,496 3.8 (2.9 – 5.1) 3,066,000

40–59 years 1,230 5.8 (4.1 – 8.1) 4,557,000

60 years and older 1,612 16.7 (13.7 – 20.1) 7,748,000

Gender

Males 3,719 6.8 (5.4 – 8.6) 9,439,000

Females 3,825 6.2 (5.0 – 7.7) 8,965,000

Race/ethnicity

Mexican Americans 1,834 2.8 (1.7 – 4.4) 722,000

Non-Hispanic Blacks 1,993 2.5 (1.8 – 3.4) 846,000

Non-Hispanic Whites 3,152 7.6 (6.1 – 9.4) 14,546,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
1. Water-Soluble Vitamins 69

Table 1.7.d. Plasma methylmalonic acid: Prevalence by survey cycle

Prevalence (in percent) of high plasma methylmalonic acid concentration (> 271 nmol/L) for the U.S. 

population, National H ealth and Nutrition Examination Survey, 1999–2004. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 3 years and older

 1999–2000 7,597 5.5 (4.8 – 6.3) 14,367,000

 2001–2002 8,451 5.3 (4.6 – 6.0) 14,218,000

 2003–2004 7,544 6.5 (5.3 – 7.9) 17,887,000

Age group

3–5 years

 1999–2000 376 § §

 2001–2002 453 § §

 2003–2004 421 4.5‡ (2.0 – 9.7) 553,000‡

6–11 years

 1999–2000 898 2.5‡ (1.1 – 5.6) 623,000‡

 2001–2002 1,031 1.5‡ (0.7 – 3.0) 372,000‡

 2003–2004 806 § §

12–19 years

 1999–2000 2,132 3.3 (2.1 – 5.3) 1,061,000

 2001–2002 2,220 3.3 (2.1 – 5.3) 1,079,000

 2003–2004 1,979 3.2 (2.2 – 4.6) 1,054,000

20–39 years

 1999–2000 1,474 4.5 (3.2 – 6.1) 3,496,000

 2001–2002 1,715 3.7 (2.6 – 5.0) 2,888,000

 2003–2004 1,496 3.8 (2.9 – 5.1) 3,066,000

40–59 years

 1999–2000 1,210 4.0 (3.0 – 5.2) 2,803,000

 2001–2002 1,491 4.7 (3.6 – 6.1) 3,557,000

 2003–2004 1,230 5.8 (4.1 – 8.1) 4,557,000

60 years and older

 1999–2000 1,507 13.9 (11.7 – 16.6) 5,986,000

 2001–2002 1,541 13.9 (12.0 – 16.1) 6,225,000

 2003–2004 1,612 16.7 (13.7 – 20.1) 7,748,000

Gender

Males

 1999–2000 3,708 5.7 (4.7 – 6.9) 7,231,000

 2001–2002 4,091 5.1 (4.3 – 6.0) 6,671,000

 2003–2004 3,719 6.8 (5.4 – 8.6) 9,157,000

Females

 1999–2000 3,889 5.3 (4.5 – 6.3) 7,133,000

 2001–2002 4,360 5.5 (4.6 – 6.5) 7,546,000

 2003–2004 3,825 6.2 (5.0 – 7.7) 8,723,000

Race/ethnicity

Mexican Americans

 1999–2000 2,595 3.2 (2.0 – 5.0) 632,000

 2001–2002 2,131 2.9 (2.2 – 3.8) 656,000

 2003–2004 1,834 2.8 (1.7 – 4.4) 687,000

Non-Hispanic Blacks

 1999–2000 1,732 2.5 (1.6 – 3.7) 803,000

 2001–2002 2,036 2.6 (1.7 – 3.9) 842,000

 2003–2004 1,993 2.5 (1.8 – 3.4) 817,000

Non-Hispanic Whites

 1999–2000 2,573 6.1 (5.3 – 7.1) 11,346,000

 2001–2002 3,605 5.9 (5.2 – 6.8) 11,036,000

 2003–2004 3,152 7.6 (6.1 – 9.4) 14,198,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
70 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

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72 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Vitamin C (Ascorbic Acid)

Background Information

Sources and Physiological Functions. Vitamin C, a water-soluble vitamin, is a collective term 

used to refer to L-ascorbic acid (the functional form of the vitamin), dehydro-L-ascorbic acid (the 

oxidized form, DHA), and monodehydro-L-ascorbic acid (the free radical form). Greater than 

95% of vitamin C in human plasma exists as ascorbic acid (Jacob 1990). The most abundant 

dietary sources of vitamin C are orange juice, grapefruit juice, peaches, sweet red peppers, and 

papayas, followed by a variety of other fruits, vegetables, and fortified cereals. Vitamin C is a 

powerful antioxidant and a cofactor in various reduction reactions; it is a known electron donor 

for at least eight human enzymes involved in the hydroxylation of collagen and the biosynthesis 

of carnitine, hormones, and amino acids. Humans and a few other mammals, such as monkeys 

and guinea pigs, are unable to biosynthesize vitamin C from glucose and must obtain the vitamin 

from outside sources.

Approximately 70–90% of the ascorbic acid consumed is absorbed by the human body at 

usual intakes of 30–180 milligrams per day (mg/d). Bioavailability of vitamin C from food or 

supplemental sources is equivalent. Vitamin C administered after the plasma has reached a point 

of saturation (approximately 70 μmol/L) will likely be excreted as unmetabolized ascorbic acid in 

the urine (Institute of Medicine 2000).

Health Effects. The clinical manifestation of vitamin C deficiency is scurvy. Scurvy can occur if 

intake is below 10 mg/d for many weeks. Important signs and symptoms of scurvy include coiled 

hairs, follicular hyperkeratosis, fatigue, bleeding gums, and delayed wound-healing (Institute of 

Medicine 2000). Too much vitamin C can cause gastrointestinal upset, but such upset is generally 

seen only at an intake exceeding 2 gram/d, and it usually disappears within one to two weeks of 

discontinuation. High intakes of vitamin C supplements have the potential to increase urinary 

oxalate excretion, which is a risk factor for the formation of calcium oxalate kidney stones, but 

evidence is conflicting.

Vitamin C, in combination with other supplements, including vitamin E, zinc, and betacarotene, has been shown to slow the progression of age-related macular degeneration (AREDS 

Research Group 2001). There is conflicting evidence for the reduction of risk of cardiovascular 

disease mortality by vitamin C supplementation and its effect on cardiovascular health in general 

(Shekelle 2003). More research is also needed to determine the role vitamin C plays in cancer 

prevention and treatment. 

Intake Recommendations. The recommended daily allowance (RDA) of vitamin C for adults 

is 120% of the EAR (estimated average requirement), which was determined by the maximally 

protective neutrophil vitamin C concentration. For men, this equates to 90 mg/d, with 75 mg 

being the appropriate daily amount for women (Institute of Medicine 2000). RDAs range from 

15–25 mg/d for children one to eight years of age, 45–75 mg/d for boys aged nine to 18 years, 

and 45–65 mg/d for girls aged nine to 18 years. For infants aged 0 to 12 months, the RDA is set 

at the amount of vitamin C commonly received through regular breastfeeding and the additional 

amount obtained through solid foods during the seven to 12 month period (an average of 45 

mg/d). A number of factors, such as bioavailability, interactions with other nutrients, smoking 

status, age, and gender, affect the amount of vitamin C required by humans. For example, people 

who smoke require an additional 35 mg/d of vitamin C due to the increased ascorbic acid needed 

to repair oxidant damage (Institute of Medicine 2000).
1. Water-Soluble Vitamins 73

Biochemical Indicators and Methods.

Vitamin C status can be assessed by 

measuring total ascorbic acid (oxidized 

and reduced) in serum or plasma, buffycoat, or leucocytes. Ascorbic acid in plasma 

is considered an index of the circulating 

vitamin available to tissues, and in leucocytes 

(particularly polymorphonuclear) it is 

believed to be a good indicator of tissue 

stores. Vitamin C deficiency is generally 

defined as plasma or serum concentrations 

less than 11.4 micromoles per liter (μmol/L), 

or the level at which signs and symptoms 

of scurvy may appear. Serum ascorbic acid 

concentrations between 11.4–23 μmol/L are 

considered low (Gibson 2005).

Clinical laboratories generally use international system (SI) units for vitamin C (μmol/L); 

however, some use conventional units (mg per deciliter [mg/dL]). The conversion factor to 

conventional units is: 1 μmol/L = 0.0176 mg/dL. 

High-performance liquid chromatography (HPLC) methods with electrochemical detection, 

which provide necessary sensitivity and specificity, are generally used to quantitate serum vitamin 

C concentrations. Older spectrophotometric assays were susceptible to interferences from a 

number of substances, such as riboflavin and aspirin. A multi-level standard reference material 

(SRM 970) is available from the National Institute of Standards and Technology (NIST) for 

human serum with certified values for ascorbic acid. The Micronutrients Measurement Quality 

Assurance Program (MMQAP) sponsored by NIST hosts inter-laboratory comparison studies 

directed at assuring high quality measurements of serum vitamin C.

Data in NHANES. An HPLC method with electrochemical detection was used to determine 

serum vitamin C concentrations in NHANES 2003–2006 (McCoy 2005). Because of the 

incorporation of an internal standard, improved accuracy and precision was achieved with this 

method compared to the previous method used during NHANES III (1988–1994). 

An analysis of NHANES 2003–2004 data showed that the highest serum concentrations of 

vitamin C were found in children and older persons. Mean concentrations among adult smokers 

were one-third lower than those of nonsmokers. In NHANES 2003–2004, the prevalence of 

vitamin C deficiency was significantly lower than that during NHANES III, but smokers and 

low-income persons were among those at increased risk of deficiency (Schleicher 2009). 

For more information about vitamin C, see the Institute of Medicine’s Dietary Reference Intake 

reports (Institute of Medicine, Food and Nutrition Board 2000) and fact sheets from the National 

Institutes of Health, Office of Dietary Supplements (http://ods.od.nih.gov/factsheets/VitaminC_

pf.asp).
74 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Highlights

Serum vitamin C concentrations in the U.S. population showed the following demographic 

patterns and characteristics:

•	 The highest concentrations were generally found in the youngest age group and higher 

concentrations were found in females compared to males.

•	 The likelihood of being vitamin C deficient or having low serum vitamin C 

concentrations varied by demographic subgroup.

Serum vitamin C concentrations less than 11.4 μmol/L may indicate vitamin C deficiency. 

Compared to non-Hispanic whites, Mexican Americans and non-Hispanic blacks had a lower 

risk of deficiency; compared to females, males had a higher risk of deficiency (Figure H.1.e). A 

number of important variables that impact vitamin C status are not addressed in this analysis, 

including smoking, overweight/obesity, socioeconomic status, and supplement use (Schleicher 

2009). Considering that manifest vitamin C deficiency is rare in the United States (Olmedo 

2006), persons categorized as vitamin C deficient may more likely experience latent scurvy, which 

is characterized by fatigue, irritability, vague, dull aching pains and weight loss (Prinzo 1999). 

Serum vitamin C concentrations between 11.4–23 μmol/L are considered low. The prevalence 

of deficient (< 11.4 μmol/L) and of low (11.4–23 μmol/L) serum vitamin C concentrations was 

significantly lower in children than in persons 20 years and older (Figure H.1.f).

a a 

b a 

b 

0 

2 

4 

6 

8 

10 

Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Male Female 

Prevalence (%) 

< 11.4 μmol/L

Race/ethnicity Gender 

Figure H.1.e. Age-adjusted prevalence estimates of vitamin C deficiency 

(serum concentrations less than 11.4 μmol/L) in the U.S. population 

aged 6 years and older by race/ethnicity or gender, National Health and 

Nutrition Examination Survey, 2003–2006. 

Error bars represent 95% confidence intervals. Bars not sharing a common letter 

differ by race/ethnicity or gender (p < 0.05). Age-adjustment was done using direct 

standardization.

0 

2 

4 

6 

8 

10 

12 

14 

6-11 12-19 20-39 40-59 60 6-11 12-19 20-39 40-59 60 

Prevalence (%) 

Age in years 

< 11.4 μmol/L 11.4–23 μmol/L

*

*

Figure H.1.f. Prevalence estimates of vitamin C deficiency (serum 

concentrations less than 11.4 μmol/L) and of low vitamin C 

concentrations (11.4–23 μmol/L) in the U.S. population aged 6 years 

and older by age group, National Health and Nutrition Examination 

Survey, 2003–2006.

Error bars represent 95% confidence intervals. *Prevalence in children is 

significantly lower than prevalence in persons 20 years and older (p < 0.05).
1. Water-Soluble Vitamins 75

Detailed Observations

The selected observations mentioned below are derived from the tables and figures presented next. 

Statements about categorical differences between demographic groups noted below are based on 

non-overlapping confidence limits from univariate analysis without adjusting for demographic 

variables (e.g., age, sex, race/ethnicity) or other blood concentration determinants (e.g., dietary 

intake, supplement usage, smoking, BMI). A multivariate analysis may alter the size and statistical 

significance of these categorical differences. Furthermore, additional significant differences of 

smaller magnitude may be present despite their lack of mention here (e.g., if confidence limits 

slightly overlap or if differences are not statistically significant before covariate adjustment has 

occurred). For a selection of citations of descriptive NHANES papers related to these biochemical 

indicators of diet and nutrition, see Appendix G.

Arithmetic mean concentrations (NHANES 2003–2006):

•	 The distribution of serum vitamin C concentrations was reasonably symmetric and for 

that reason we present arithmetic means.

•	 Serum vitamin C concentrations followed a U-shaped pattern, with the lowest 

concentrations seen in 20–59 year old persons (Table 1.8.a.1 and Figure 1.8.a).

•	 Females had higher serum vitamin C concentrations than males (Table 1.8.a.1).

•	 We observed no differences in serum vitamin C concentrations among race/ethnic 

groups (Table 1.8.a.1).

Changes in arithmetic mean concentrations across survey cycles:

•	 No changes in the serum vitamin C concentrations (Table 1.8.b) were observed between 

2003–2004 and 2005–2006.

Prevalence estimates of low or high biochemical indicator concentrations:

•	 Six percent of the population aged 6 years and older had serum vitamin C 

concentrations < 11.4 μmol/L (Table 1.8.c). 

•	 Children (<1%) and adolescents (3%) had a lower prevalence of low serum vitamin C 

concentrations than older age groups (5–8%). 

•	 Non-Hispanic whites (7%) had a higher prevalence of low serum vitamin C 

concentrations than non-Hispanic blacks (4%) and Mexican Americans (3%).
76

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.8.a.1. Serum vitamin C: Concentrations

Arithmetic mean and selected percentiles of serum concentrations (in μmol/L) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006.

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 56.1 (54.6 – 57.6) 6.12 (5.47 – 6.91) 9.61 (8.17 – 10.9) 56.3 (54.9 – 57.6) 103 (101 – 105) 116 (113 – 120) 14,579Age group6–11 years 75.1 (73.0 – 77.2) 21.3 (16.1 – 24.2) 29.0 (25.0 – 33.7) 74.5 (72.6 – 76.5) 123 (115 – 131) 138 (128 – 153) 1,703

12–19 years 58.0 (55.9 – 60.2) 10.2 (7.68 – 11.9) 15.2 (11.9 – 17.0) 58.6 (55.9 – 60.7) 98.9 (94.5 – 103) 109 (105 – 115) 3,984

20–39 years 51.0 (48.8 – 53.2) 6.01 (4.60 – 7.31) 9.00 (7.48 – 10.3) 51.4 (49.2 – 53.9) 92.9 (89.4 – 96.9) 102 (98.0 – 107) 3,233

40–59 years 51.6 (49.7 – 53.4) 4.92 (4.06 – 5.69) 7.41 (5.91 – 8.77) 52.4 (50.6 – 53.9) 97.2 (94.3 – 101) 111 (105 – 117) 2,635

60 years and older 63.0 (61.5 – 64.6) 6.91 (5.53 – 7.90) 10.7 (8.16 – 13.6) 62.5 (61.1 – 63.9) 117 (112 – 121) 131 (127 – 142) 3,024

GenderMales 52.4 (50.9 – 54.0) 5.80 (4.89 – 6.48) 8.38 (7.09 – 9.70) 52.6 (51.2 – 54.0) 98.9 (96.4 – 102) 110 (107 – 115) 7,155

Females 59.7 (57.9 – 61.4) 7.06 (5.74 – 8.15) 11.2 (9.61 – 12.9) 59.6 (58.1 – 61.2) 106 (103 – 111) 121 (117 – 128) 7,424

Race/ethnicityMexican Americans 55.2 (52.7 – 57.7) 9.49 (7.64 – 12.1) 15.1 (11.6 – 18.7) 55.1 (52.8 – 57.7) 93.7 (90.7 – 96.0) 101 (97.6 – 107) 3,628

Non-Hispanic Blacks 54.3 (52.7 – 56.0) 7.38 (5.75 – 9.18) 11.9 (10.0 – 14.0) 54.0 (52.2 – 55.9) 95.2 (92.7 – 97.5) 104 (101 – 110) 3,784

Non-Hispanic Whites 56.5 (54.6 – 58.4) 5.75 (5.05 – 6.36) 8.56 (7.26 – 9.92) 56.9 (54.9 – 58.7) 105 (103 – 108) 120 (115 – 125) 6,089
1. Water-Soluble Vitamins 77

6−11 12−19 20−39 40−59 60+

0 20 40 60 80 100

Serum vitamin C

(μmol/L)

Overall

6−11 12−19 20−39 40−59 60+

Mexican Americans

Females

Males

6−11 12−19 20−39 40−59 60+

0 20 40 60 80 100

Non−Hispanic Blacks

Serum vitamin C

(μmol/L)

6−11 12−19 20−39 40−59 60+

Non−Hispanic Whites

6−11 12−19 20−39 40−59 60+

0 20 40 60 80 100

Serum vitamin C

(μmol/L)

Females

Age (years)

6−11 12−19 20−39 40−59 60+

Males

Age (years)

Mexican

 Americans

Non−Hispanic

 Blacks

Non−Hispanic

 Whites

Figure 1.8.a. Serum vitamin C: Concentrations by age group

Arithmetic mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006
78 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.8.a.2. Serum vitamin C: Total population

Arithmetic mean and selected percentiles of serum concentrations (in μmol/L) for the total U.S. population 

aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006.

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 6 years and older 56.1 (54.6 – 57.6) 9.61 (8.17 – 10.9) 56.3 (54.9 – 57.6) 103 (101 – 105) 14,579

6–11 years 75.1 (73.0 – 77.2) 29.0 (25.0 – 33.7) 74.5 (72.6 – 76.5) 123 (115 – 131) 1,703

12–19 years 58.0 (55.9 – 60.2) 15.2 (11.9 – 17.0) 58.6 (55.9 – 60.7) 98.9 (94.5 – 103) 3,984

20–39 years 51.0 (48.8 – 53.2) 9.00 (7.48 – 10.3) 51.4 (49.2 – 53.9) 92.9 (89.4 – 96.9) 3,233

40–59 years 51.6 (49.7 – 53.4) 7.41 (5.91 – 8.77) 52.4 (50.6 – 53.9) 97.2 (94.3 – 101) 2,635

60 years and older 63.0 (61.5 – 64.6) 10.7 (8.16 – 13.6) 62.5 (61.1 – 63.9) 117 (112 – 121) 3,024

Males

Total, 6 years and older 52.4 (50.9 – 54.0) 8.38 (7.09 – 9.70) 52.6 (51.2 – 54.0) 98.9 (96.4 – 102) 7,155

6–11 years 76.3 (73.1 – 79.5) 30.4 (21.7 – 37.7) 76.2 (72.5 – 78.7) 123 (113 – 138) 837

12–19 years 55.8 (53.6 – 58.1) 14.7 (11.2 – 16.5) 56.0 (53.4 – 58.5) 94.0 (91.2 – 100) 2,022

20–39 years 47.9 (45.3 – 50.4) 8.58 (6.68 – 9.87) 48.4 (45.2 – 50.8) 87.5 (82.8 – 95.4) 1,463

40–59 years 46.7 (44.5 – 48.9) 6.38 (4.89 – 7.94) 48.2 (46.1 – 50.2) 88.4 (84.8 – 96.3) 1,305

60 years and older 57.2 (54.9 – 59.4) 7.92 (6.72 – 10.1) 57.2 (54.7 – 59.4) 110 (105 – 118) 1,528

Females

Total, 6 years and older 59.7 (57.9 – 61.4) 11.2 (9.61 – 12.9) 59.6 (58.1 – 61.2) 106 (103 – 111) 7,424

6–11 years 73.8 (71.1 – 76.6) 28.5 (20.3 – 35.9) 72.4 (69.2 – 75.9) 123 (115 – 131) 866

12–19 years 60.4 (57.8 – 62.9) 15.7 (11.0 – 18.8) 61.4 (58.6 – 63.9) 102 (98.2 – 110) 1,962

20–39 years 54.1 (51.5 – 56.7) 9.90 (7.73 – 11.5) 55.3 (51.9 – 58.6) 96.1 (91.9 – 101) 1,770

40–59 years 56.2 (53.7 – 58.7) 9.34 (6.29 – 12.0) 56.4 (53.6 – 58.2) 103 (97.4 – 110) 1,330

60 years and older 67.8 (65.9 – 69.7) 14.3 (10.9 – 16.4) 67.0 (65.1 – 69.0) 121 (116 – 129) 1,496

Table 1.8.a.3. Serum vitamin C: Mexican Americans

Arithmetic mean and selected percentiles of serum concentrations (in μmol/L) for Mexican Americans in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006.

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 6 years and older 55.2 (52.7 – 57.7) 15.1 (11.6 – 18.7) 55.1 (52.8 – 57.7) 93.7 (90.7 – 96.0) 3,628

6–11 years 73.4 (69.4 – 77.4) 28.3 (20.7 – 37.8) 74.2 (71.7 – 76.4) 113 (107 – 130) 563

12–19 years 58.5 (56.4 – 60.5) 20.3 (14.9 – 23.9) 59.0 (57.4 – 60.7) 92.7 (90.6 – 95.2) 1,266

20–39 years 52.2 (49.4 – 54.9) 15.9 (12.2 – 20.6) 52.4 (49.9 – 54.5) 85.7 (80.9 – 90.6) 782

40–59 years 49.5 (46.9 – 52.1) 9.55 (7.54 – 14.0) 51.0 (47.5 – 54.7) 83.6 (80.0 – 85.2) 470

60 years and older 51.8 (47.8 – 55.8) 9.48 (2.78 – 14.5) 50.5 (46.0 – 55.9) 93.6 (88.9 – 103) 547

Males

Total, 6 years and older 52.7 (50.0 – 55.5) 13.6 (8.67 – 17.5) 53.3 (50.4 – 55.7) 90.8 (87.6 – 94.5) 1,762

6–11 years 73.4 (69.0 – 77.8) 28.2 (20.8 – 37.5) 74.6 (71.4 – 77.2) 113 (108 – 134) 275

12–19 years 56.7 (54.3 – 59.1) 18.9 (10.6 – 23.3) 57.4 (55.2 – 59.5) 90.1 (86.9 – 93.0) 628

20–39 years 49.6 (46.2 – 53.1) 14.2 (7.50 – 22.1) 50.8 (47.7 – 54.4) 79.5 (73.6 – 86.6) 351

40–59 years 46.2 (42.8 – 49.7) 8.27 (4.43 – 13.6) 46.3 (43.5 – 53.5) 76.5 (73.9 – 87.2) 239

60 years and older 44.8 (41.6 – 47.9) 7.27 (1.70 – 10.0) 44.0 (38.1 – 48.9) 86.3 (78.5 – 94.2) 269

Females

Total, 6 years and older 58.0 (55.4 – 60.6) 18.6 (14.1 – 21.5) 58.1 (54.8 – 60.8) 95.1 (92.4 – 99.2) 1,866

6–11 years 73.4 (69.1 – 77.7) 26.5 (18.0 – 41.2) 73.3 (70.7 – 76.2) 113 (103 – 129) 288

12–19 years 60.3 (57.8 – 62.8) 22.4 (18.8 – 24.7) 60.7 (58.4 – 62.7) 95.1 (90.9 – 104) 638

20–39 years 55.1 (51.7 – 58.6) 18.5 (12.8 – 22.6) 54.0 (50.6 – 58.0) 90.0 (84.3 – 102) 431

40–59 years 53.1 (49.9 – 56.3) 10.6 (7.49 – 18.2) 54.5 (50.0 – 58.9) 85.2 (83.9 – 92.9) 231

60 years and older 57.7 (51.6 – 63.8) 14.3 (1.10 – 23.2) 58.7 (48.3 – 64.2) 97.9 (93.4 – 116) 278
1. Water-Soluble Vitamins 79

Table 1.8.a.4. Serum vitamin C: Non-Hispanic blacks

Arithmetic mean and selected percentiles of serum concentrations (in μmol/L) for non-Hispanic blacks in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 6 years and older 54.3 (52.7 – 56.0) 11.9 (10.0 – 14.0) 54.0 (52.2 – 55.9) 95.2 (92.7 – 97.5) 3,784

6–11 years 73.4 (70.8 – 75.9) 39.7 (34.0 – 43.0) 72.8 (69.0 – 75.9) 107 (103 – 118) 544

12–19 years 61.5 (59.7 – 63.2) 28.1 (25.9 – 30.3) 61.3 (59.1 – 63.2) 95.0 (91.7 – 98.3) 1,400

20–39 years 51.5 (49.4 – 53.5) 14.7 (11.2 – 16.9) 50.4 (48.1 – 53.2) 87.3 (83.4 – 91.3) 711

40–59 years 49.2 (46.3 – 52.1) 8.58 (4.80 – 11.2) 48.9 (45.3 – 52.7) 93.1 (83.9 – 101) 619

60 years and older 49.8 (46.8 – 52.8) 6.69 (4.99 – 8.42) 50.8 (47.0 – 54.1) 95.9 (90.8 – 101) 510

Males

Total, 6 years and older 52.6 (51.0 – 54.1) 10.2 (7.77 – 12.6) 52.1 (50.4 – 54.2) 92.8 (90.2 – 97.3) 1,895

6–11 years 75.3 (71.0 – 79.6) 42.4 (34.1 – 44.3) 75.8 (69.8 – 79.9) 108 (104 – 118) 272

12–19 years 59.6 (58.0 – 61.2) 28.6 (24.2 – 30.2) 58.8 (56.4 – 61.0) 91.6 (89.5 – 96.1) 735

20–39 years 48.7 (46.3 – 51.2) 12.4 (6.93 – 16.2) 48.0 (44.0 – 50.9) 81.5 (76.6 – 91.0) 337

40–59 years 46.7 (43.3 – 50.1) 7.24 (4.00 – 10.4) 46.6 (42.2 – 51.3) 82.8 (77.1 – 97.4) 291

60 years and older 45.6 (41.0 – 50.3) 5.02 (2.96 – 6.19) 45.6 (38.6 – 50.9) 93.0 (89.0 – 106) 260

Females

Total, 6 years and older 55.8 (53.7 – 58.0) 13.5 (11.3 – 15.8) 55.8 (53.5 – 58.1) 95.9 (94.1 – 99.8) 1,889

6–11 years 71.3 (68.9 – 73.7) 36.8 (30.8 – 41.4) 68.8 (67.0 – 73.1) 106 (102 – 114) 272

12–19 years 63.4 (60.7 – 66.1) 27.6 (25.9 – 30.8) 63.8 (60.6 – 67.0) 96.0 (92.8 – 102) 665

20–39 years 53.7 (50.9 – 56.6) 15.7 (11.5 – 21.5) 52.7 (49.4 – 56.3) 90.5 (86.6 – 95.8) 374

40–59 years 51.3 (47.8 – 54.8) 9.84 (4.02 – 14.5) 50.4 (47.2 – 55.2) 95.9 (86.6 – 106) 328

60 years and older 52.7 (48.8 – 56.7) 9.64 (4.66 – 11.2) 54.0 (50.1 – 58.2) 96.5 (90.0 – 108) 250

Table 1.8.a.5. Serum vitamin C: Non-Hispanic whites

Arithmetic mean and selected percentiles of serum concentrations (in μmol/L) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 6 years and older 56.5 (54.6 – 58.4) 8.56 (7.26 – 9.92) 56.9 (54.9 – 58.7) 105 (103 – 108) 6,089

6–11 years 75.6 (72.5 – 78.8) 25.7 (18.7 – 31.8) 74.8 (70.9 – 77.7) 128 (118 – 144) 436

12–19 years 57.2 (54.0 – 60.4) 12.3 (9.88 – 15.7) 58.0 (53.2 – 61.5) 101 (95.4 – 107) 1,037

20–39 years 50.6 (47.8 – 53.3) 7.99 (6.39 – 8.99) 51.2 (47.7 – 55.1) 96.2 (91.2 – 102) 1,442

40–59 years 52.0 (49.7 – 54.3) 6.80 (5.56 – 8.33) 52.8 (51.2 – 55.2) 99.8 (96.0 – 103) 1,346

60 years and older 64.8 (63.0 – 66.7) 11.7 (8.22 – 14.7) 63.9 (62.4 – 65.3) 118 (114 – 123) 1,828

Males

Total, 6 years and older 52.3 (50.4 – 54.1) 7.71 (6.50 – 8.82) 52.4 (50.5 – 54.5) 101 (98.2 – 104) 2,990

6–11 years 76.5 (71.7 – 81.4) 25.4† (14.0 – 34.1) 75.8 (69.2 – 80.6) 127† (117 – 155) 210

12–19 years 54.9 (51.7 – 58.1) 12.6 (9.73 – 16.2) 54.8 (51.4 – 59.1) 94.4 (91.6 – 104) 524

20–39 years 47.2 (44.2 – 50.3) 7.92 (6.52 – 8.79) 47.5 (44.1 – 50.7) 93.8 (85.8 – 98.7) 636

40–59 years 47.0 (44.3 – 49.8) 6.19 (4.90 – 7.44) 48.5 (46.4 – 51.0) 90.2 (86.4 – 101) 687

60 years and older 58.5 (56.0 – 61.1) 8.15 (6.84 – 11.5) 58.4 (55.6 – 60.7) 112 (106 – 119) 933

Females

Total, 6 years and older 60.5 (58.2 – 62.8) 9.92 (8.18 – 11.7) 60.7 (58.5 – 62.8) 110 (106 – 114) 3,099

6–11 years 74.7 (70.3 – 79.0) 25.2 (9.65 – 36.1) 72.8 (68.7 – 78.2) 129 (115 – 145) 226

12–19 years 59.6 (55.8 – 63.5) 12.0 (8.98 – 15.7) 61.1 (56.9 – 64.7) 104 (98.6 – 120) 513

20–39 years 53.9 (50.4 – 57.4) 8.06 (5.40 – 9.86) 56.0 (50.2 – 60.7) 99.0 (93.1 – 106) 806

40–59 years 57.0 (53.9 – 60.0) 8.63 (5.81 – 11.1) 57.4 (53.5 – 59.8) 105 (98.0 – 113) 659

60 years and older 70.0 (67.7 – 72.3) 15.0 (10.9 – 17.9) 69.1 (66.5 – 72.6) 123 (117 – 131) 895

† Estimate is subject to greater uncertainty due to small cell size.
80 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.8.b. Serum vitamin C: Concentrations by survey cycle

Arithmetic mean and selected percentiles of serum concentrations (in μmol/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 2003–2006. 

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2003–2004 55.8 (53.1 – 58.5) 8.55 (6.57 – 10.2) 56.3 (53.4 – 58.8) 103 (101 – 108) 7,277

 2005–2006 56.4 (54.8 – 58.0) 11.1 (9.22 – 12.4) 56.3 (55.0 – 57.6) 102 (99.2 – 105) 7,302

Age group

6–11 years

 2003–2004 74.3 (70.9 – 77.8) 27.8 (16.6 – 35.5) 73.7 (70.8 – 76.8) 126 (112 – 139) 823

 2005–2006 75.9 (73.1 – 78.7) 32.0 (26.2 – 36.6) 75.0 (72.4 – 78.1) 121 (114 – 130) 880

12–19 years

 2003–2004 56.3 (52.9 – 59.8) 13.6 (10.2 – 16.2) 56.2 (52.1 – 60.0) 98.4 (93.6 – 106) 2,016

 2005–2006 59.7 (57.0 – 62.4) 17.0 (13.4 – 20.8) 60.3 (57.3 – 63.5) 99.3 (93.0 – 107) 1,968

20–39 years

 2003–2004 49.7 (46.0 – 53.5) 7.34 (5.42 – 9.22) 50.0 (45.7 – 54.1) 95.0 (87.9 – 102) 1,540

 2005–2006 52.2 (49.7 – 54.8) 11.3 (9.71 – 12.5) 52.8 (49.7 – 55.7) 91.9 (87.8 – 97.1) 1,693

40–59 years

 2003–2004 52.6 (49.4 – 55.8) 6.71 (5.02 – 8.71) 53.5 (51.2 – 56.6) 100 (95.5 – 105) 1,266

 2005–2006 50.6 (48.3 – 52.9) 7.92 (5.51 – 10.9) 51.3 (48.9 – 53.4) 94.4 (90.1 – 100) 1,369

60 years and older

 2003–2004 63.2 (60.8 – 65.6) 10.3 (7.88 – 13.3) 62.5 (60.2 – 64.7) 119 (114 – 124) 1,632

 2005–2006 62.9 (60.7 – 65.1) 11.8 (6.99 – 15.1) 62.6 (60.7 – 64.5) 113 (108 – 119) 1,392

Gender

Males

 2003–2004 52.2 (49.4 – 54.9) 7.32 (5.74 – 9.08) 52.7 (50.1 – 55.2) 100 (97.7 – 103) 3,590

 2005–2006 52.7 (51.0 – 54.3) 9.74 (7.88 – 11.0) 52.4 (50.9 – 53.9) 97.3 (93.7 – 102) 3,565

Females

 2003–2004 59.3 (56.4 – 62.3) 9.76 (7.89 – 11.4) 59.8 (56.7 – 62.5) 108 (102 – 115) 3,687

 2005–2006 60.0 (57.9 – 62.1) 13.1 (11.1 – 15.6) 59.4 (57.7 – 61.4) 105 (101 – 111) 3,737

Race/ethnicity

Mexican Americans

 2003–2004 55.4 (50.6 – 60.2) 14.0 (7.30 – 20.1) 55.6 (51.7 – 60.0) 93.1 (89.3 – 97.1) 1,766

 2005–2006 55.1 (52.8 – 57.5) 17.1 (10.8 – 20.6) 54.6 (51.7 – 57.5) 94.2 (90.8 – 97.3) 1,862

Non-Hispanic Blacks

 2003–2004 52.9 (50.3 – 55.4) 11.1 (7.65 – 13.5) 52.0 (49.7 – 55.5) 93.7 (90.5 – 99.1) 1,880

 2005–2006 55.7 (53.6 – 57.9) 13.0 (9.49 – 16.8) 55.4 (53.5 – 57.6) 95.6 (94.0 – 99.2) 1,904

Non-Hispanic Whites

 2003–2004 56.7 (53.1 – 60.3) 7.82 (6.24 – 9.09) 57.4 (53.1 – 60.6) 108 (103 – 115) 3,103

 2005–2006 56.3 (54.5 – 58.0) 10.0 (7.77 – 11.7) 56.4 (54.7 – 58.0) 103 (100 – 106) 2,986
1. Water-Soluble Vitamins 81

0

10

20

30

40

5th Percentile

Total

(6+y)03−04

05−06

3−5y03−04

05−06

6−11y03−04

05−06

12−19y03−04

05−06

20+y03−04

05−06

Males03−04

05−06

Females03−04

05−06

MA 03−04

05−06

NHB 03−04

05−06

NHW03−04

05−06

40

50

60

70

80

50th Percentile

80

100

120

140

95th Percentile

Figure 1.8.b. Serum vitamin C: Concentrations by survey cycle

Selected percentiles in μmol/L (95% condence intervals), National Health and 

Nutrition Examination Survey, 2003–2006
82 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 1.8.c. Serum vitamin C: Prevalence

Prevalence (in percent) of low serum vitamin C concentration (< 11.4 μmol/L) for the U.S. population 

aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Sample 

size

Prevalence

(95% conf. interval)

Estimated total 

number of persons

Total, 6 years and older 14,579 6.0 (4.9 – 7.3) 15,757,000

Age group

 6–11 years 1,703 0.8‡ (0.4 – 1.7) 191,000‡

 12–19 years 3,984 2.8 (1.9 – 4.2) 931,000

 20–39 years 3,233 6.9 (5.4 – 8.9) 5,533,000

 40–59 years 2,635 8.1 (6.3 – 10.5) 6,435,000

 60 years and older 3,024 5.1 (3.8 – 6.8) 2,362,000

Gender

 Males 7,155 7.3 (5.9 – 9.0) 9,258,000

 Females 7,424 4.8 (3.8 – 6.0) 6,476,000

Race/ethnicity

 Mexican Americans 3,628 3.1 (2.1 – 4.6) 715,000

 Non-Hispanic Blacks 3,784 4.3 (3.2 – 5.7) 1,341,000

 Non-Hispanic Whites 6,089 7.1 (5.8 – 8.7) 12,807,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.
1. Water-Soluble Vitamins 83

Table 1.8.d. Serum vitamin C: Prevalence by survey cycle

Prevalence (in percent) of low serum vitamin C concentration (< 11.4 μmol/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 2003–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 6 years and older

 2003–2004 7,277 7.3 (5.5 – 9.6) 19,054,000

 2005–2006 7,302 4.8 (3.7 – 6.1) 12,746,000

Age group

6–11 years

 2003–2004 823 1.5‡ (0.7 – 3.6) 372,000‡

 2005–2006 880 § §

12–19 years

 2003–2004 2,016 3.3 (1.9 – 5.7) 1,090,000

 2005–2006 1,968 2.3‡ (1.2 – 4.5) 783,000‡

20–39 years

 2003–2004 1,540 9.3 (6.7 – 12.8) 7,437,000

 2005–2006 1,693 4.5 (3.2 – 6.4) 3,618,000

40–59 years

 2003–2004 1,266 9.2 (6.5 – 13.0) 7,294,000

 2005–2006 1,369 7.1 (4.7 – 10.5) 5,815,000

60 years and older

 2003–2004 1,632 5.5 (3.9 – 7.5) 2,543,000

 2005–2006 1,392 4.7 (2.8 – 7.8) 2,272,000

Gender

Males

 2003–2004 3,590 8.4 (6.0 – 11.8) 10,772,000

 2005–2006 3,565 6.1 (4.8 – 7.7) 7,914,000

Females

 2003–2004 3,687 6.1 (4.6 – 8.0) 8,247,000

 2005–2006 3,737 3.5 (2.4 – 5.1) 4,827,000

Race/ethnicity

Mexican Americans

 2003–2004 1,766 3.7 (2.0 – 6.7) 840,000

 2005–2006 1,862 2.6 (1.6 – 4.2) 627,000

Non-Hispanic Blacks

 2003–2004 1,880 4.8 (3.4 – 6.8) 1,510,000

 2005–2006 1,904 3.8 (2.3 – 6.2) 1,199,000

Non-Hispanic Whites

 2003–2004 3,103 8.6 (6.4 – 11.5) 15,534,000

 2005–2006 2,986 5.6 (4.2 – 7.4) 10,186,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
84 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

References

Age-Related Eye Disease Study Research Group. A randomized, placebo-controlled, clinical trial of high-dose 

supplementation with vitamins C and E and beta carotene for age-related cataract and vision loss: AREDS report 

no. 9. Arch Ophthalmol. 2001;119:1439–1452.

Gibson RS. Principles of nutritional assessment (2nd edn.). New York: Oxford University Press; 2005.

Institute of Medicine, Food and Nutrition Board. Dietary reference intakes for vitamin C, vitamin E, selenium, 

and carotenoids. Washington, D.C.: National Academy Press; 2000.

Jacob RA. Assessment of human vitamin C status. J Nutr. 1990;120 Suppl 11:1480–1485.

McCoy LF, Bowen MB, Xu M, Chen H, Schleicher RL. Improved HPLC assay for measuring serum vitamin C 

with 1-methyluric acid used as an electrochemically active internal standard. Clin Chem. 2005;51:1062–1064.

Olmedo JM, Yiannias JA, Windgassen EB, Gornet MK. Scurvy: a disease almost forgotten. Int J Dermatol. 

2006;45:909–913.

Prinzo ZW. Scurvy and its prevention and control in major emergencies. Geneva, Switzerland: World Health 

Organization, 1999. (WHO publication WHO/NHD/99.11.)

Schleicher RL, Carroll MD, Ford ES, Lacher DA. Serum vitamin C and the prevalence of vitamin C deficiency in 

the United States: 2003–2004 National Health and Nutrition Examination Survey (NHANES). Am J Clin Nutr. 

2009;90:1252–1263.

Shekelle P, Morton S, Hardy M. Effect of Supplemental Antioxidants Vitamin C, Vitamin E, and Coenzyme Q10 

for the Prevention and Treatment of Cardiovascular Disease. Evid Report Tech Asses No. 83. AHRQ Publication 

No. 03-E043. Rockville, MD: Agency for Healthcare Research and Quality. July 2003.


2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 8787

2. Fat-Soluble Vitamins and 

Nutrients

Vitamins A and E and Carotenoids

•	 Vitamin A

•	 Retinyl palmitate

•	 Retinyl stearate

•	 Vitamin E

•	 gamma-Tocopherol

•	 alpha-Carotene

•	 trans-beta-Carotene

•	 cis-beta-Carotene

•	 beta-Cryptoxanthin

•	 Lutein and zeaxanthin

•	 trans-Lycopene

•	 Total lycopene (cis- and trans-)

Vitamin D

•	 25-Hydroxyvitamin D

Fatty Acids

Saturated

•	 Myristic acid (14:0)

•	 Palmitic acid (16:0)

•	 Stearic acid (18:0)

•	 Arachidic acid (20:0)

•	 Docosanoic acid (22:0)

•	 Lignoceric acid (24:0)

Monounsaturated

•	 Myristoleic acid (14:1n-5)

•	 Palmitoleic acid (16:1n-7)

•	 cis-Vaccenic acid (18:1n-7)

•	 Oleic acid (18:1n-9)

•	 Eicosenoic acid (20:1n-9)

•	 Docosenoic acid (22:1n-9)

•	 Nervonic acid (24:1n-9)

Polyunsaturated

•	 Linoleic acid (18:2n-6)

•	 alpha-Linolenic acid (18:3n-3)

•	 gamma-Linolenic acid (18:3n-6)

•	 Eicosadienoic acid (20:2n-6)

•	 homo-gamma-Linolenic acid

(20:3n-6)

•	 Arachidonic acid (20:4n-6)

•	 Eicosapentaenoic acid (20:5n-3)

•	 Docosatetraenoic acid (22:4n-6)

•	 Docosapentaenoic acid (22:5n-3)

•	 Docosapentaenoic acid (22:5n-6)

•	 Docosahexaenoic acid (22:6n-3)
88 2nd 88 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Vitamins A, E and Carotenoids

Background Information

Sources and Physiological Functions. Vitamins A (retinol) and E (alpha-tocopherol) and the

carotenoids are fat-soluble micronutrients found in many foods, including some vegetables,

fruits, meats, and animal products. Fish-liver oils, liver, egg yolks, butter, and cream are known

for their higher content of vitamin A. Nuts and seeds are particularly rich sources of vitamin E

(Thomas 2006). At least 700 carotenoids—fat-soluble red and yellow pigments—are found in

nature (Britton 2004). Americans consume 40–50 of these carotenoids, primarily in fruits and

vegetables (Khachik 1992), and smaller amounts in poultry products, including egg yolks, as well

as in seafoods (Boylston 2007). Eight different carotenoids are easily measured in human serum:

alpha-carotene, cis- and trans-beta-carotene, beta-cryptoxanthin, lutein, cis- and trans-lycopene,

and zeaxanthin. Main sources of carotenes are orange-colored fruits and vegetables such as carrots,

pumpkins, and mangos. Lutein and zeaxanthin are also found in dark green leafy vegetables,

where any orange coloring is overshadowed by chlorophyll. Trans-lycopene is obtained primarily

from tomatoes and tomato products and some fruits. For information on the carotenoid content

of U.S. foods, see the 1998 carotenoid database created by the U.S. Department of Agriculture

and the Nutrition Coordinating Center at the University of Minnesota (http://www.nal.usda.gov/

fnic/foodcomp/Data/car98/car98.html).

Vitamin A, found in foods that come from animal sources, is called preformed vitamin A.

Some carotenoids found in colorful fruits and vegetables are called provitamin A because they

are metabolized in the body to vitamin A. Among the carotenoids, beta-carotene, a retinol

dimer consisting of two linked retinol molecules, has the most significant provitamin A activity.

Approximately 12 micrograms (μg) of dietary beta-carotene can provide the equivalent of 1 μg

of retinol. Other provitamin A carotenoids, such as alpha-carotene and beta-cryptoxanthin, are

half as active as beta-carotene (Institute of Medicine 2000). The bioconversion of carotenoids

to vitamin A is highly variable from person to person (Krinsky 2005). Retinyl esters serve as the

storage form of vitamin A and are mostly concentrated in the liver.

The absorption of fat-soluble micronutrients from the gastrointestinal tract depends on processes

responsible for fat absorption or metabolism. Thus, people with conditions resulting in fat

malabsorption (e.g., celiac disease, Crohn’s disease, pancreatic disorders) can develop vitamin

A deficiency over time. Vitamin A also has interactions with other nutrients. Iron and zinc

deficiency can affect vitamin A metabolism and transport of vitamin A stores from the liver to

body tissues (Institute of Medicine 2001). The absorption of carotenoids from foods is highly

dependent on cooking techniques that break down plant cell walls and release carotenoids; it is

also dependent on the availability of dietary fat to enhance carotenoid uptake (Krinsky 2005).

The liver regulates the concentration of vitamin A in the circulation by releasing stored retinyl

esters as needed; only when liver reserves are nearly exhausted does serum vitamin A fall into the

deficient range (Napoli 2006). The variation in serum carotenoid concentrations among people in

the United States is relatively large, primarily reflecting wide-ranging differences in dietary intake

(Lacher 2005).

Vitamin E activity is derived from at least eight naturally occurring tocopherols, the most potent

of which is alpha-tocopherol. Other less active forms of vitamin E are plentiful in the U.S. diet,

with gamma-tocopherol being the predominant form. The most commonly consumed sources

of alpha-tocopherol in the diet of American adults are mixed foods (spaghetti sauce, pizza and

chili), fried potatoes, salad dressings, and bakery goods (Ahuja 2004). Other important sources are
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 8989

tomatoes, eggs, nuts and seeds, and snack foods. Plasma concentrations of tocopherols vary widely

among healthy individuals and are highly correlated with plasma lipid concentrations (Ford 1999;

Ford 2006).

Health Effects. Inadequate or excessive intake of vitamins A or E can lead to various disorders.

For example, vitamin A deficiency, considered to be the main cause of childhood blindness in

low-income countries (Roodhooft 2002), is a rare condition in the United States. Prominent signs

of vitamin A deficiency include night blindness, corneal thinning, and conjunctival metaplasia.

Vitamin A is also essential for proper immune function, epithelial growth and repair, bone

growth, reproduction, and normal embryonic and fetal development (West 2006). Acute toxicity

resulting from single or short-term large doses of preformed vitamin A is characterized by nausea,

vomiting, headache, vertigo, blurred vision, increased cerebrospinal fluid pressure, and lack of

muscular coordination. Central nervous system effects, liver abnormalities, bone and skin changes,

and other nonspecific adverse effects can be indicative of chronic hypervitaminosis A. Consuming

excess amounts of vitamin A during early pregnancy may lead to serious birth defects (Institute of

Medicine 2001).

Serum or plasma concentrations of carotenoids are considered among the best biological markers

for fruit and vegetable intake. The strongest dietary predictors of serum carotenoid concentrations

are fruits (for sources of beta-cryptoxanthin), carrots and root vegetables (for sources of carotenes),

and tomato products (for sources of trans-lycopene) (Al-Delaimy 2005). Research studies have

shown inconsistencies in the relation between carotenoid intake and protection from cancer.

Carotenoids in foods, even when consumed over long periods and in large amounts are not

known to produce adverse health effects. However, results of intervention studies of smokers

who used 20–30 milligrams (mg) of beta-carotene per day showed that this group had more lung

cancers than placebo-treated groups (Albanes 1996; Redlich 1998).

Vitamin E deficiency occurs only rarely in people, and overt deficiency symptoms in people

consuming low-vitamin E diets have never been described (Institute of Medicine 2000). The

main manifestation of vitamin E deficiency is peripheral neuropathy characterized by the

degeneration of the large-caliber axons of sensory neurons (Institute of Medicine 2000). The

upper limit (UL) for vitamin E intake (1000 mg/day) is based on hemorrhagic effects; however,

a causal association between excess alpha-tocopherol intake in apparently healthy individuals and

adverse health outcomes has not consistently been shown (Institute of Medicine 2000). Studies

evaluating tocopherols to reduce the risk for cardiovascular disease demonstrated inconsistent

findings (Agency for Healthcare Research and Quality 2003). The American Heart Association

currently advises that antioxidant supplements (such as vitamins E and C and beta-carotene)

should not be used for primary or secondary prevention of cardiovascular disease (Lichtenstein

2006). Nevertheless, the American Heart Association recommends consuming food sources of

antioxidant nutrients, principally from a variety of plant-derived foods such as fruits, vegetables,

whole grains, and vegetable oils.

Intake Recommendations. The National Academy of Sciences has established dietary-requirement

intake values for vitamins A and E by determining the Adequate Intake (AI) for infants and the

recommended dietary allowance (RDA) for older age groups (Institute of Medicine 2000 and 2001).

The RDA for vitamin A in retinol equivalents is 900 μg/day for men and 700 μg/day for women;

for children and adolescents (1–18 years), the RDA ranges from 300–900 μg/day. For infants (0–12

months), the AI is set at 400–500 μg/day of retinol equivalents. The Tolerable Upper Intake Level

(UL) for adults is set at 3,000 μg/day of preformed vitamin A, whereas the UL for infants (600 μg/

day), younger children 1–8 years (600-900 μg/day), older children 9–13 years (1700 μg/day), and
90 2nd 90 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

adolescents 14–18 years (2800 μg/day) are age-dependent. For adults, the RDA for vitamin E is 15

mg/day of alpha-tocopherol; for children and adolescents (1–18 years), the RDA ranges from 6–15

mg/day. There is no RDA for other forms of vitamin E, such as gamma-tocopherol. The UL for

vitamin E which applies to all eight stereoisomers of alpha-tocopherol is 1000 mg/day for adults;

a UL for infants could not be established and thus only food and formula sources of dietary intake

are recommended. The UL for children and adolescents ranges from 200-800 mg/day of vitamin

E. Although no quantitative recommendations are available for the intake of carotenoids, existing

recommendations support increased consumption of carotenoid-rich fruits and vegetables. Current

public health guidelines advise that people consume at least 2.5 cups of fruits and vegetables a day,

depending on caloric need, to ensure adequate nutrient intake (U.S. Department of Agriculture and

U.S. Department of Health and Human Services 2010).

Biochemical Indicators and Methods. The best way to determine inadequate vitamin A status

is through hepatic biopsy, but this invasive procedure is unsuitable for population studies. Serum

or plasma retinol is measured by use of high performance liquid chromatography (HPLC) with

ultraviolet (UV) detection after separation from its carrier retinol binding protein (RBP). Because

retinol is closely correlated with RBP, the measurement of this transport protein through enzymelinked immunosorbent assay (ELISA) has also been used to assess vitamin A status. In most

populations, serum RBP has been shown to be a suitable surrogate for retinol. Serum or plasma

concentrations of carotenoids are measured by use of HPLC and visible light (450 nm) absorbance.

Clinical laboratories typically use conventional units for serum concentrations of these fat-soluble

micronutrients (μg per deciliter [dL]). Conversion factors to international system (SI) units are 1

μg/dL = 0.0349 micromole per liter (mmol/L) for vitamin A and 1 μg/dL = 0.02322 mmol/L for

vitamin E. Depending on its molecular weight, each carotenoid has a specific conversion factor.

International reference materials for vitamins A and E and carotenoids are available from the U.S.

National Institutes of Standards and Technology (https://www-s.nist.gov/srmors/view_detail.

cfm?srm=968e). Among most laboratories participating in an external quality assurance program,

standardized HPLC methods for measuring fat-soluble micronutrients show consistent agreement

of values (Duewer 2000).

The diagnosis of vitamin A or E deficiency is supported by measuring these concentrations in the

body. People with serum retinol concentrations of less than 20 μg/dL are considered vitamin A

deficient, and those with serum concentrations of less than 10 μg/dL are considered severely deficient

(West 2006). Serum retinol values do not always reflect total body status because of homeostatic

control and therefore are often not useful for assessing

the vitamin A status of individuals. Additional tests

may be required to confirm vitamin A deficiency

when 20 μg/dL is used as a cutoff (Gibson 2005). The

distribution of serum retinol values in a population

together with the prevalence of individuals with serum

retinol values below a given cutoff point provide

important information about the vitamin A status of

a population. WHO (2011) recommends using the

prevalence of serum retinol concentrations of less than

or equal to 20 μg/dL to define public health problems

involving vitamin A deficiency as mild (2–9%),

moderate (10–19%) or severe (≥20%). In chronic

hypervitaminosis A, serum concentrations are generally

greater than 100 μg/dL (Bendich 1989). Carotenoid
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 9191

deficiency has no defined serum concentrations. The laboratory diagnosis of vitamin E deficiency is

based on serum concentrations of alpha-tocopherol (less than 500 μg/dL or less than 0.8 mg of alphatocopherol per gram of total lipids) (Beers 2006). Such concentrations are associated with in vitro

hydrogen peroxide-induced red blood cell lysis, not with clinical deficiency symptoms (Institute of

Medicine 2000).

Data in NHANES. The fat-soluble micronutrients vitamin A, E, and carotenoids presented in

this report were measured by a single assay panel employing HPLC separation and detection by

use of UV or visible light (HPLC-UV/vis). This is the same method used during the first four

years of the continuous NHANES survey (1999-2002).

Since 1971, various fat-soluble micronutrients have been measured in the serum of NHANES

participants. In NHANES III (1988–1994), clinically low concentrations of serum retinol were

uncommon in U.S. residents aged 4 years and older, although racial/ethnic and socioeconomic

differences existed (Ballew 2001). Variations in serum carotenoid concentrations by ethnicity

and sex were found for adults, children, and adolescents (Ford 2000; Ford 2002). Ford et al. also

found sociodemographic variations in serum concentrations of alpha-tocopherol among U.S.

adults in NHANES III (1999) and alpha- and gamma-tocopherol in NHANES 1999–2000

(2006). Application of the most common cut-off value for serum alpha-tocopherol concentrations

in NHANES 1999–2000 (500 μg/dL), demonstrated a low prevalence of vitamin E deficiency,

despite the fact that the U.S. Department of Agriculture-estimated dietary intakes of vitamin E

were low and that most of the U.S. population did not meet dietary intake recommendations.

For more information on these fat-soluble micronutrients, see the Institute of Medicine’s

Dietary Reference Intake reports (Institute of Medicine 2000 and 2001) and the vitamin fact

sheets from the National Institutes of Health, Office of Dietary Supplements (http://ods.od.nih.

gov/Health_Information/Vitamin_and_Mineral_Supplement_Fact_Sheets.aspx).

Highlights

Serum concentrations of fat-soluble micronutrients (vitamin A, E, and carotenoids) in the U.S.

population showed the following demographic patterns and characteristics:

•	 With few exceptions, the highest concentrations of fat-soluble micronutrients were

found in persons 60 years and older.

•	 No consistent pattern was observed with regard to gender or race/ethnicity.

•	 The likelihood of being vitamin A or E deficient was very low throughout the

population.

•	 The likelihood of vitamin A excess was also very low, but it increased with increasing age.

For more than 20 years, the majority of the U.S. population (greater than 95%) has had adequate

serum concentrations of vitamin A (> 20 μg/dL) and vitamin E (> 500 μg/dL).

Despite NHANES 2001–2002 dietary intake data demonstrating that 93% of the U.S.

population consumed less than the Estimated Average Requirement (EAR) for vitamin E

(Moshfegh 2005), for decades mean serum vitamin E concentrations have remained consistently

adequate (Figure H.2.a), with less than 1% of the population vitamin E deficient. Analyses of

NHANES data showed that in 1999–2000, 52% of adults (Rock 2007) and in 2003–2006,

49% of the total U.S. population (Bailey 2011) used dietary supplements; thus, the intake data

(food and supplements) for vitamin E seem to be inconsistent with the biomarker data. Several

explanatory possibilities have been raised, including a suggestion that the intake of fats (and
92 2nd 92 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

fat-soluble nutrients) is under-reported in overweight and obese subjects, the database of food

values is not accurate, and/or that the EAR for vitamin E needs adjustment. Low intake without

widespread manifestation of deficiency suggests the need for further evaluations to determine

whether improved estimates are necessary, either in the nutrient tables or in dietary intake.

Figure H.2.a. Age-adjusted geometric mean concentrations of serum vitamin E (alpha-tocopherol) in the U.S. population aged 6 years

and older by gender or race/ethnicity, National Health and Nutrition Examination Survey, 1988–2006.

Error bars represent 95% confidence intervals. Within a demographic group, bars not sharing a common letter differ (p < 0.05). Age adjustment was

done using direct standardization.

Detailed Observations

The selected observations mentioned below are derived from the tables and figures presented next.

Statements about categorical differences between demographic groups noted below are based on

non-overlapping confidence limits from univariate analysis without adjusting for demographic

variables (e.g., age, gender, race/ethnicity) or other blood concentration determinants (e.g., dietary

intake, supplement usage, smoking, BMI). A multivariate analysis may alter the size and statistical

significance of these categorical differences. Furthermore, additional significant differences of

smaller magnitude may be present despite their lack of mention here (e.g., if confidence limits

slightly overlap or if differences are not statistically significant before covariate adjustment has

occurred). For a selection of citations of descriptive NHANES papers related to these biochemical

indicators of diet and nutrition, see Appendix G.

Geometric mean concentrations (NHANES 2005–2006):

•	 Serum vitamin A concentrations increased with age (Table 2.1.a.1 and Figure 2.1.a).

•	 Serum retinyl palmitate concentrations were similar across age ranges, with a slight

decrease in the adolescent years (Table 2.2.a.1 and Figure 2.2.a).

•	 Serum vitamin E concentrations decreased throughout childhood, then increased with

age to concentrations higher than those seen in early childhood (Table 2.4.a.1and Figure

2.4.a), while serum gamma-tocopherol concentrations remained relatively constant

throughout the life cycle, decreasing slightly in older persons (Table 2.5.a.1 and Figure

2.5.a).

a a a a 

a 

a 

b b b 

b 

b 

b c c b b 

b 

c 

0 

200 

400 

600 

800 

1000 

1200 

Total 

population 

Males Females Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Serum vitamin E (μg/dL) 

1988-1994 1999-2002 2005-2006 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 9393

•	 Serum alpha-carotene, trans-beta-carotene, and lutein/zeaxanthin concentrations

decreased throughout childhood, then increased with age to concentrations higher than

those seen in early childhood (Tables 2.6.a.1, 2.7.a.1, and 2.10.a.1 and Figures 2.6.a,

2.7.a, 2.10.a).

•	 Serum beta-cryptoxanthin concentrations decreased in early childhood and then

remained steady (Table 2.9.a.1 and Figure 2.9.a).

•	 Serum trans-lycopene and total lycopene concentrations were highest in young adults

and lowest in older persons (Tables 2.11.a.1 and 2.12.a.1 and Figures 2.11.a, 2.12.a).

•	 Females had higher serum vitamin E than males, while males had higher serum vitamin

A concentrations than females (Tables 2.4.a.1 and 2.1.a.1).

•	 Females had higher serum alpha-carotene and trans-beta-carotene concentrations than

males, and males had higher serum total lycopene concentrations than females (Tables

2.6.a.1, 2.7.a.1, and 2.12.a.1).

•	 Non-Hispanic whites had the highest concentrations of serum vitamin A and vitamin

E, and the lowest concentrations of serum gamma-tocopherol. Non-Hispanic whites

had the lowest concentrations of serum lutein/zeaxanthin. Non-Hispanic blacks had

the lowest concentrations of serum alpha-carotene. Mexican Americans had the highest

concentrations of serum beta-cryptoxanthin and the lowest concentrations of serum

trans-lycopene and total lycopene. (Tables 2.1.a.1, 2.4.a.1, 2.5.a.1, 2.10.a.1, 2.6.a.1,

2.9.a.1, 2.11.a.1, and 2.12.a.1).

Changes in geometric mean concentrations across survey cycles:

•	 Serum vitamin A concentrations increased between 1999–2000 and 2001–2002, then

held steady through the 2005–2006 survey period (Table 2.1.b).

•	 Serum vitamin E and gamma-tocopherol concentrations held steady between 1999–

2000 and 2005–2006 (Tables 2.4.b and 2.5.b).

•	 Serum alpha-carotene, trans-beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin,

and trans-lycopene concentrations did not change appreciably across the survey cycles

(Tables 2.6.b, 2.7.b, 2.9.b, 2.10.b, and 2.11.b).

•	 Prevalence estimates of low or high biochemical indicator concentrations:

•	 In 2005–2006, less than 1% of the population aged 6 years and older had a vitamin A

or vitamin E deficiency, defined as < 20 μg/dL and < 500 μg/dL, respectively (Tables

2.1.c.1 and 2.4.c). About 2%, however, were at risk for an excess of vitamin A, or > 100

μg/dL (Table 2.1.c.2).

•	 Between 1999 and 2006, the prevalence of low serum vitamin A was less than 1% of all

persons (Table 2.1.d.1), and the prevalence of high serum vitamin A was 1–2% of all

persons (Table 2.1.d.2).

•	 Between 1999 and 2006, the prevalence of low serum vitamin E was 2% or less for

almost all groups except for adolescents, for whom the prevalence was 2–4% (Table

2.4.d).
94

2nd 94 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.1.a.1. Serum vitamin A: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 54.7 (53.8 – 55.6) 29.6 (28.7 – 30.5) 32.5 (31.8 – 33.2) 55.2 (54.2 – 56.1) 87.8 (85.6 – 90.5) 96.7 (93.1 – 101) 7,254 Age group 6–11 years 36.4 (35.6 – 37.2) 22.8 (19.9 – 24.8) 25.6 (24.3 – 26.9) 36.6 (35.9 – 37.3) 52.4 (49.1 – 54.3) 54.4 (53.3 – 57.3) 860 12–19 years 46.5 (45.4 – 47.7) 28.9 (28.6 – 29.6) 32.0 (30.6 – 33.0) 46.0 (44.6 – 47.5) 69.6 (66.9 – 73.1) 75.7 (71.4 – 82.9) 1,954 20–39 years 54.3 (53.3 – 55.3) 31.2 (29.2 – 32.1) 33.9 (32.2 – 35.1) 54.7 (53.5 – 55.6) 84.4 (81.9 – 87.9) 89.1 (87.2 – 93.3) 1,688 40–59 years 58.7 (57.7 – 59.7) 33.1 (31.4 – 34.2) 36.8 (36.0 – 38.0) 59.5 (58.1 – 60.4) 90.3 (87.2 – 94.3) 100 (94.7 – 107) 1,365 60 years and older 64.4 (62.8 – 66.1) 36.4 (31.6 – 38.8) 40.2 (38.2 – 43.0) 64.9 (63.1 – 67.0) 99.8 (96.2 – 102) 108 (105 – 115) 1,387 Gender Males 57.2 (56.3 – 58.2) 30.3 (29.2 – 31.2) 33.6 (32.7 – 34.8) 58.0 (57.1 – 59.0) 89.0 (86.5 – 93.0) 100 (93.3 – 104) 3,547 Females 52.4 (51.3 – 53.5) 28.9 (27.7 – 30.1) 31.9 (31.2 – 32.6) 52.4 (50.8 – 53.8) 85.9 (83.3 – 88.7) 94.8 (89.8 – 103) 3,707 Race/ethnicity Mexican Americans 48.4 (47.3 – 49.5) 27.8 (26.2 – 28.6) 30.3 (29.3 – 31.2) 48.8 (46.8 – 50.2) 73.7 (71.9 – 77.0) 82.1 (76.2 – 88.4) 1,844 Non-Hispanic Blacks 48.3 (47.3 – 49.3) 25.7 (23.8 – 27.5) 28.8 (27.6 – 29.8) 48.1 (47.0 – 49.5) 82.0 (78.4 – 85.5) 89.7 (86.1 – 93.6) 1,891 Non-Hispanic Whites 57.4 (56.4 – 58.4) 31.5 (30.6 – 32.4) 34.8 (33.0 – 36.2) 57.9 (56.8 – 59.0) 89.8 (87.6 – 93.3) 100 (95.6 – 104) 2,973
6−11 12−19 20−39 40−59 60+ 

0 20 40 60 80 

Serum vitamin A

(μg/dL) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

80

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.1.a. Serum vitamin A: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006 Serum vitamin A Serum vitamin A (μg/dL) (μg/dL) 0 20 40 60 80 0 20 40 60 

6−11 12−19 20−39 

Females 

40−59 60+ 6−11 12−19 20−39 

Males 

40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

6−11 12−19 

Age (years) 

20−39 40−59 60+ 6−11 12−19 

Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 9595
96 2nd 96 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.1.a.2. Serum vitamin A: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 54.7 (53.8 – 55.6) 36.6 (35.8 – 37.4) 55.2 (54.2 – 56.1) 80.0 (78.1 – 82.2) 7,254

6–11 years 36.4 (35.6 – 37.2) 28.0 (27.5 – 29.1) 36.6 (35.9 – 37.3) 47.5 (45.7 – 50.1) 860

12–19 years 46.5 (45.4 – 47.7) 35.2 (33.9 – 35.9) 46.0 (44.6 – 47.5) 63.2 (60.7 – 66.9) 1,954

20–39 years 54.3 (53.3 – 55.3) 38.1 (36.5 – 39.2) 54.7 (53.5 – 55.6) 77.7 (74.1 – 81.6) 1,688

40–59 years 58.7 (57.7 – 59.7) 41.2 (39.5 – 43.0) 59.5 (58.1 – 60.4) 81.0 (79.0 – 85.2) 1,365

60 years and older 64.4 (62.8 – 66.1) 46.4 (44.7 – 47.9) 64.9 (63.1 – 67.0) 88.4 (86.0 – 91.7) 1,387

Males

Total, 6 years and older 57.2 (56.3 – 58.2) 38.5 (37.8 – 39.2) 58.0 (57.1 – 59.0) 81.8 (79.7 – 85.0) 3,547

6–11 years 36.4 (35.4 – 37.3) 28.1 (26.4 – 29.1) 36.3 (35.0 – 37.2) 47.5 (45.7 – 51.6) 427

12–19 years 48.2 (46.9 – 49.6) 36.4 (35.3 – 37.7) 48.1 (46.3 – 49.8) 64.5 (62.9 – 67.4) 980

20–39 years 59.1 (57.7 – 60.5) 44.4 (42.3 – 46.0) 58.4 (56.8 – 60.2) 80.9 (76.8 – 84.5) 738

40–59 years 61.8 (60.7 – 63.0) 44.2 (41.6 – 47.1) 63.2 (62.4 – 64.2) 84.5 (80.1 – 92.0) 673

60 years and older 66.0 (63.9 – 68.1) 48.4 (46.0 – 50.0) 66.4 (63.7 – 68.7) 90.4 (86.3 – 97.2) 729

Females

Total, 6 years and older 52.4 (51.3 – 53.5) 35.6 (34.3 – 36.4) 52.4 (50.8 – 53.8) 77.5 (75.0 – 79.0) 3,707

6–11 years 36.5 (35.3 – 37.8) 28.0 (27.5 – 29.4) 36.9 (35.9 – 38.0) 47.0 (45.1 – 52.3) 433

12–19 years 44.7 (43.5 – 45.9) 33.7 (33.3 – 35.0) 43.8 (42.7 – 45.1) 60.7 (57.0 – 66.6) 974

20–39 years 50.0 (48.7 – 51.3) 34.5 (32.7 – 36.1) 49.3 (48.3 – 50.9) 72.6 (69.5 – 75.9) 950

40–59 years 55.9 (54.1 – 57.7) 39.9 (36.9 – 41.2) 55.8 (53.8 – 58.5) 78.4 (74.2 – 82.8) 692

60 years and older 63.2 (61.3 – 65.2) 45.1 (43.0 – 47.2) 63.9 (62.5 – 65.7) 87.7 (84.0 – 91.2) 658

Table 2.1.a.3. Serum vitamin A: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 48.4 (47.3 – 49.5) 33.4 (32.6 – 34.2) 48.8 (46.8 – 50.2) 68.6 (66.7 – 70.3) 1,844

6–11 years 35.6 (34.4 – 37.0) 27.6 (24.8 – 28.9) 35.8 (33.8 – 37.6) 46.2 (45.0 – 48.2) 295

12–19 years 44.9 (43.3 – 46.4) 34.1 (33.4 – 35.0) 44.4 (43.2 – 46.1) 58.8 (55.6 – 64.7) 646

20–39 years 50.1 (49.1 – 51.2) 36.0 (33.3 – 37.3) 50.3 (48.7 – 53.3) 69.1 (66.8 – 72.7) 449

40–59 years 53.6 (52.4 – 54.8) 39.0 (36.6 – 41.0) 52.6 (50.7 – 55.6) 71.7 (67.2 – 85.3) 246

60 years and older 55.5 (52.8 – 58.3) 40.8 (37.3 – 42.8) 57.0 (54.7 – 58.4) 78.1 (72.9 – 85.4) 208

Males

Total, 6 years and older 51.9 (50.0 – 53.9) 36.5 (33.7 – 38.5) 53.3 (50.2 – 55.9) 70.7 (68.8 – 73.3) 883

6–11 years 35.6 (33.9 – 37.4) 27.2 (24.0 – 28.8) 35.4 (33.0 – 38.7) 46.8 (45.6 – 49.1) 145

12–19 years 47.4 (45.6 – 49.3) 36.1 (33.8 – 38.0) 47.0 (45.0 – 48.6) 60.9 (58.7 – 65.7) 313

20–39 years 54.8 (52.4 – 57.3) 41.3 (36.6 – 43.9) 56.0 (54.0 – 59.0) 70.6 (68.0 – 74.3) 198

40–59 years 59.1 (56.0 – 62.3) 45.8 (42.9 – 47.4) 57.9 (53.9 – 63.1) 77.7 (70.5 – 110) 122

60 years and older 57.6 (53.3 – 62.3) 42.6† (19.8 – 47.4) 57.6 (55.1 – 62.0) 79.5† (70.6 – 93.0) 105

Females

Total, 6 years and older 44.7 (44.0 – 45.5) 32.1 (31.3 – 32.7) 43.7 (42.7 – 45.2) 64.2 (62.1 – 67.0) 961

6–11 years 35.7 (34.6 – 36.8) 28.0 (24.0 – 29.4) 36.0 (34.3 – 37.6) 45.7 (42.2 – 52.7) 150

12–19 years 42.3 (41.0 – 43.7) 33.3 (32.2 – 33.8) 41.6 (40.2 – 43.0) 55.9 (52.3 – 61.5) 333

20–39 years 45.0 (43.9 – 46.2) 31.9 (29.8 – 33.8) 43.2 (41.7 – 46.6) 66.6 (61.2 – 69.5) 251

40–59 years 48.4 (47.1 – 49.7) 35.6 (32.4 – 37.4) 49.1 (46.5 – 50.2) 63.9 (57.7 – 81.3) 124

60 years and older 53.8 (50.9 – 56.9) 39.4† (32.9 – 42.3) 53.5 (51.4 – 58.9) 75.9† (72.9 – 83.0) 103

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 9797

Table 2.1.a.4. Serum vitamin A: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 48.3 (47.3 – 49.3) 32.0 (31.2 – 32.8) 48.1 (47.0 – 49.5) 72.1 (70.0 – 75.1) 1,891

6–11 years 35.6 (34.0 – 37.3) 26.6 (24.0 – 28.5) 35.7 (34.5 – 36.8) 47.3 (44.6 – 51.8) 240

12–19 years 41.1 (40.0 – 42.2) 30.5 (29.4 – 31.3) 40.9 (39.7 – 42.6) 54.2 (52.8 – 57.5) 665

20–39 years 47.3 (45.8 – 48.9) 32.3 (29.8 – 35.3) 47.9 (44.9 – 50.5) 67.7 (63.6 – 71.6) 368

40–59 years 53.2 (51.4 – 55.0) 35.4 (33.3 – 37.2) 53.7 (50.3 – 57.2) 77.1 (72.8 – 85.7) 335

60 years and older 59.9 (56.3 – 63.7) 40.1 (36.2 – 45.6) 60.7 (56.6 – 64.5) 85.1 (78.8 – 91.4) 283

Males

Total, 6 years and older 51.2 (49.9 – 52.5) 34.0 (32.9 – 35.2) 51.9 (50.2 – 53.6) 74.8 (70.9 – 79.0) 949

6–11 years 35.4 (34.1 – 36.8) 26.2 (23.2 – 28.7) 35.3 (33.5 – 36.6) 46.2 (43.7 – 51.9) 128

12–19 years 42.2 (40.8 – 43.7) 30.6 (28.8 – 32.0) 42.0 (39.7 – 44.7) 58.1 (55.1 – 60.7) 343

20–39 years 53.3 (52.1 – 54.5) 38.9 (35.7 – 40.4) 54.1 (52.3 – 55.5) 71.2 (65.9 – 77.7) 170

40–59 years 57.3 (54.9 – 59.8) 39.0 (35.8 – 42.6) 58.4 (54.0 – 62.9) 84.8 (74.8 – 92.7) 156

60 years and older 60.8 (57.0 – 64.9) 40.0 (33.9 – 46.7) 62.5 (59.9 – 64.7) 86.0 (78.4 – 110) 152

Females

Total, 6 years and older 45.9 (44.7 – 47.1) 31.1 (29.4 – 32.1) 44.9 (43.5 – 46.7) 70.1 (65.9 – 74.6) 942

6–11 years 35.8 (33.0 – 39.0) 26.7 (19.8 – 28.8) 36.1 (33.0 – 38.8) 47.6 (44.2 – 54.2) 112

12–19 years 39.9 (38.7 – 41.2) 30.1 (29.4 – 30.8) 40.2 (38.7 – 41.7) 51.1 (49.9 – 53.1) 322

20–39 years 42.7 (41.1 – 44.3) 29.2 (24.3 – 32.0) 42.4 (40.4 – 44.5) 60.4 (57.4 – 63.5) 198

40–59 years 49.9 (46.8 – 53.3) 33.4 (31.9 – 34.3) 48.8 (45.9 – 53.5) 73.3 (68.1 – 84.7) 179

60 years and older 59.3 (55.4 – 63.4) 39.8 (36.7 – 43.8) 60.3 (54.6 – 64.5) 84.9 (77.9 – 90.2) 131

Table 2.1.a.5. Serum vitamin A: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 57.4 (56.4 – 58.4) 39.0 (37.8 – 40.0) 57.9 (56.8 – 59.0) 82.0 (79.8 – 85.3) 2,973

6–11 years 36.8 (35.5 – 38.2) 28.6 (26.6 – 30.1) 37.1 (35.4 – 38.2) 47.6 (45.3 – 53.0) 231

12–19 years 48.5 (46.8 – 50.2) 37.0 (35.5 – 38.4) 48.3 (45.9 – 50.0) 66.2 (63.1 – 69.3) 499

20–39 years 57.5 (55.9 – 59.1) 41.4 (39.1 – 43.0) 57.1 (56.0 – 58.6) 81.4 (77.1 – 85.6) 714

40–59 years 60.4 (59.2 – 61.6) 43.3 (41.2 – 45.6) 60.5 (59.3 – 62.6) 81.9 (79.2 – 88.0) 683

60 years and older 65.4 (63.8 – 67.0) 47.1 (45.3 – 48.8) 66.0 (63.8 – 67.9) 89.5 (86.7 – 92.6) 846

Males

Total, 6 years and older 59.7 (58.5 – 60.9) 40.9 (39.4 – 41.9) 60.4 (58.9 – 62.1) 84.1 (80.7 – 87.8) 1,472

6–11 years 37.0 (35.6 – 38.6) 28.6 (25.1 – 30.3) 37.0 (35.1 – 38.4) 47.4 (45.3 – 53.2) 112

12–19 years 50.2 (48.3 – 52.2) 38.5 (35.2 – 40.4) 49.8 (47.5 – 52.0) 66.8 (64.3 – 69.7) 254

20–39 years 61.8 (59.9 – 63.8) 47.1 (45.1 – 48.4) 60.8 (58.3 – 63.5) 83.8 (79.8 – 87.8) 309

40–59 years 63.3 (61.5 – 65.2) 45.3 (40.1 – 49.9) 64.0 (62.7 – 66.1) 85.0 (80.0 – 101) 351

60 years and older 66.8 (64.6 – 69.0) 49.7 (46.1 – 50.4) 67.1 (63.8 – 70.2) 90.6 (87.3 – 99.0) 446

Females

Total, 6 years and older 55.3 (54.1 – 56.4) 37.6 (36.2 – 39.2) 55.6 (54.4 – 56.6) 79.8 (78.2 – 82.4) 1,501

6–11 years 36.6 (34.5 – 38.9) 28.2 (26.0 – 30.5) 37.1 (34.9 – 38.9) 48.1 (44.3 – 54.7) 119

12–19 years 46.6 (44.6 – 48.8) 35.9 (33.4 – 37.4) 45.5 (43.1 – 48.5) 63.7 (59.5 – 70.1) 245

20–39 years 53.5 (51.6 – 55.3) 36.7 (34.2 – 39.7) 53.1 (51.2 – 54.9) 76.1 (72.8 – 83.1) 405

40–59 years 57.7 (56.0 – 59.4) 41.6 (40.2 – 43.5) 57.7 (55.6 – 59.6) 79.1 (75.6 – 83.9) 332

60 years and older 64.3 (62.2 – 66.5) 46.4 (44.5 – 48.3) 64.8 (62.7 – 67.4) 87.9 (84.1 – 95.0) 400
98 2nd 98 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.1.b. Serum vitamin A: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2002 and 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 52.8 (51.8 – 53.8) 30.7 (29.8 – 31.6) 53.5 (52.2 – 54.9) 85.6 (83.9 – 87.2) 7,102

 2001–2002 55.2 (54.1 – 56.4) 32.6 (31.8 – 33.5) 56.0 (54.7 – 57.3) 88.4 (86.6 – 91.6) 7,935

 2005–2006 54.7 (53.8 – 55.6) 32.5 (31.8 – 33.2) 55.2 (54.2 – 56.1) 87.8 (85.6 – 90.5) 7,254

Age group

3–5 years

 1999–2000 32.3 (31.6 – 33.1) 22.0 (19.0 – 23.1) 33.1 (31.5 – 34.6) 46.2 (41.1 – 66.3) 352

 2001–2002 33.8 (33.1 – 34.6) 24.3 (16.5 – 25.5) 34.0 (33.1 – 35.2) 47.1 (44.3 – 50.3) 430

6–11 years

 1999–2000 35.1 (34.5 – 35.6) 25.3 (23.6 – 26.1) 35.4 (35.0 – 35.8) 48.5 (46.1 – 52.3) 866

 2001–2002 37.3 (36.2 – 38.5) 26.5 (25.8 – 27.4) 37.3 (36.2 – 39.0) 51.6 (50.1 – 54.0) 1,014

 2005–2006 36.4 (35.6 – 37.2) 25.6 (24.3 – 26.9) 36.6 (35.9 – 37.3) 52.4 (49.1 – 54.3) 860

12–19 years

 1999–2000 45.7 (44.7 – 46.6) 30.1 (29.1 – 30.9) 45.8 (45.0 – 46.9) 69.4 (66.9 – 71.8) 2,111

 2001–2002 48.0 (47.1 – 48.9) 31.8 (30.4 – 33.3) 48.5 (47.6 – 49.3) 71.2 (69.0 – 74.2) 2,206

 2005–2006 46.5 (45.4 – 47.7) 32.0 (30.6 – 33.0) 46.0 (44.6 – 47.5) 69.6 (66.9 – 73.1) 1,954

20–39 years

 1999–2000 52.1 (50.8 – 53.4) 33.0 (31.1 – 34.3) 52.8 (51.2 – 54.5) 80.3 (77.9 – 83.0) 1,461

 2001–2002 54.8 (53.3 – 56.3) 34.2 (32.6 – 35.3) 55.8 (54.4 – 57.5) 83.4 (80.9 – 86.6) 1,716

 2005–2006 54.3 (53.3 – 55.3) 33.9 (32.2 – 35.1) 54.7 (53.5 – 55.6) 84.4 (81.9 – 87.9) 1,688

40–59 years

 1999–2000 59.0 (57.6 – 60.6) 35.9 (34.2 – 38.1) 59.8 (57.9 – 61.5) 90.4 (86.4 – 96.8) 1,191

 2001–2002 60.3 (59.2 – 61.5) 37.5 (34.8 – 39.9) 61.2 (59.8 – 62.7) 94.6 (90.3 – 97.8) 1,474

 2005–2006 58.7 (57.7 – 59.7) 36.8 (36.0 – 38.0) 59.5 (58.1 – 60.4) 90.3 (87.2 – 94.3) 1,365

60 years and older

 1999–2000 62.5 (61.1 – 64.0) 39.7 (36.3 – 41.9) 63.0 (61.3 – 65.0) 94.3 (90.1 – 99.5) 1,473

 2001–2002 65.0 (63.6 – 66.5) 40.3 (38.0 – 41.4) 65.4 (64.1 – 67.4) 102 (98.6 – 108) 1,525

 2005–2006 64.4 (62.8 – 66.1) 40.2 (38.2 – 43.0) 64.9 (63.1 – 67.0) 99.8 (96.2 – 102) 1,387

Gender

(6 years and older)

Males

 1999–2000 55.8 (54.4 – 57.3) 31.9 (30.1 – 33.8) 57.5 (55.8 – 58.8) 86.3 (84.6 – 90.6) 3,450

 2001–2002 58.5 (57.2 – 59.8) 34.4 (33.4 – 35.5) 59.8 (58.0 – 61.7) 91.5 (88.7 – 93.7) 3,841

 2005–2006 57.2 (56.3 – 58.2) 33.6 (32.7 – 34.8) 58.0 (57.1 – 59.0) 89.0 (86.5 – 93.0) 3,547

Females

 1999–2000 50.1 (49.1 – 51.1) 30.2 (28.7 – 31.2) 50.0 (48.8 – 51.0) 84.1 (81.2 – 87.0) 3,652

 2001–2002 52.3 (51.1 – 53.5) 31.7 (30.9 – 32.4) 52.5 (51.0 – 53.9) 86.6 (84.0 – 88.3) 4,094

 2005–2006 52.4 (51.3 – 53.5) 31.9 (31.2 – 32.6) 52.4 (50.8 – 53.8) 85.9 (83.3 – 88.7) 3,707

Race/ethnicity

(6 years and older)

Mexican Americans

 1999–2000 47.0 (46.1 – 47.8) 29.0 (28.0 – 29.7) 46.9 (45.5 – 48.3) 75.6 (73.6 – 79.0) 2,410

 2001–2002 48.6 (47.2 – 50.0) 29.8 (28.8 – 30.7) 48.8 (47.4 – 50.4) 76.6 (73.4 – 82.1) 1,991

 2005–2006 48.4 (47.3 – 49.5) 30.3 (29.3 – 31.2) 48.8 (46.8 – 50.2) 73.7 (71.9 – 77.0) 1,844

Non-Hispanic Blacks

 1999–2000 45.8 (44.2 – 47.4) 27.8 (26.4 – 28.3) 45.4 (43.1 – 47.6) 75.7 (72.5 – 81.1) 1,590

 2001–2002 47.2 (46.1 – 48.3) 28.2 (27.4 – 28.9) 47.0 (45.3 – 48.6) 80.2 (77.3 – 85.7) 1,864

 2005–2006 48.3 (47.3 – 49.3) 28.8 (27.6 – 29.8) 48.1 (47.0 – 49.5) 82.0 (78.4 – 85.5) 1,891

Non-Hispanic Whites

 1999–2000 55.6 (54.2 – 57.1) 33.4 (31.2 – 34.7) 56.8 (55.0 – 58.2) 87.3 (85.4 – 90.5) 2,456

 2001–2002 57.9 (56.4 – 59.5) 34.7 (33.1 – 36.2) 58.9 (56.8 – 60.7) 91.3 (88.9 – 93.5) 3,455

 2005–2006 57.4 (56.4 – 58.4) 34.8 (33.0 – 36.2) 57.9 (56.8 – 59.0) 89.8 (87.6 – 93.3) 2,973
5th Percentile 50th Percentile 

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Figure 2.1.b. Serum vitamin A: Concentrations by survey cycle 

Selected percentiles in μg/dL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2002 and 2005–2006 

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99−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) (6+y) (6+y) (6+y) (6+y) (6+y) 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 9999
100 2nd 100 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.1.c.1. Serum vitamin A: Prevalence

Prevalence (in percent) of low serum vitamin A concentration (< 20 μg/dL) for the U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006.

Sample 

size

Prevalence 

(95% conf. interval)

Estimated total 

number of persons

Total, 6 years and older 7,254 0.3 (0.1 – 0.5) 711,000

Age group

 6–11 years 860 1.0 (0.6 – 1.5) 231,000

 12–19 years 1,954 § §

 20–39 years 1,688 § §

 40–59 years 1,365 § §

 60 years and older 1,387 § §

Gender

 Males 3,547 § §

 Females 3,707 0.2‡ (0.1 – 0.4) 317,000‡

Race/ethnicity

 Mexican Americans 1,844 § §

 Non-Hispanic Blacks 1,891 0.5 (0.3 – 0.7) 145,000

 Non-Hispanic Whites 2,973 0.2‡ (0.1 – 0.5) 386,000‡

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 101101

Table 2.1.c.2. Serum vitamin A: Prevalence

Prevalence (in percent) of high serum vitamin A concentration (> 100 μg/dL) for the U.S. population 

aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Sample 

size

Prevalence 

(95% conf. interval)

Estimated total 

number of persons

Total, 6 years and older 7,254 2.1 (1.6 – 2.7) 5,573,000

Age group

 6–11 years 860 § §

 12–19 years 1,954 § §

 20–39 years 1,688 1.1‡ (0.5 – 2.3) 847,000‡

 40–59 years 1,365 2.7 (1.8 – 3.9) 2,182,000

 60 years and older 1,387 4.8 (3.8 – 6.0) 2,301,000

Gender

 Males 3,547 2.5 (1.8 – 3.4) 3,265,000

 Females 3,707 1.7 (1.0 – 2.9) 2,306,000

Race/ethnicity

 Mexican Americans 1,844 0.5‡ (0.3 – 1.1) 129,000‡

 Non-Hispanic Blacks 1,891 1.1 (0.6 – 2.0) 348,000

 Non-Hispanic Whites 2,973 2.6 (2.0 – 3.5) 4,752,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
102 2nd 102 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.1.d.1. Serum vitamin A: Prevalence by survey cycle

Prevalence (in percent) of low serum vitamin A concentration (< 20 μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2002 and 2005–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 6 years and older

 1999–2000 7,102 0.1 (0.1 – 0.2) 360,000

 2001–2002 7,935 0.3 (0.2 – 0.4) 698,000

 2005–2006 7,254 0.3 (0.1 – 0.5) 711,000

Age group

3–5 years

 1999–2000 352 § §

 2001–2002 430 § §

6–11 years

 1999–2000 866 1.0 (0.6 – 1.6) 243,000

 2001–2002 1,014 § §

 2005–2006 860 1.0 (0.6 – 1.5) 231,000

12–19 years

 1999–2000 2,111 § §

 2001–2002 2,206 § §

 2005–2006 1,954 § §

20–39 years

 1999–2000 1,461 § §

 2001–2002 1,716 § §

 2005–2006 1,688 § §

40–59 years

 1999–2000 1,191 § §

 2001–2002 1,474 § §

 2005–2006 1,365 § §

60 years and older

 1999–2000 1,473 § §

 2001–2002 1,525 § §

 2005–2006 1,387 § §

Gender

(6 years and older)

Males

 1999–2000 3,450 0.1‡ (0.1 – 0.3) 179,000‡

 2001–2002 3,841 0.4 (0.2 – 0.7) 456,000

 2005–2006 3,547 § §

Females

 1999–2000 3,652 0.1 (0.1 – 0.2) 181,000

 2001–2002 4,094 0.2‡ (0.1 – 0.4) 242,000‡

 2005–2006 3,707 0.2‡ (0.1 – 0.4) 317,000‡

Race/ethnicity

(6 years and older)

Mexican Americans

 1999–2000 2,410 0.4‡ (0.2 – 0.8) 75,000‡

 2001–2002 1,991 § §

 2005–2006 1,844 § §

Non-Hispanic Blacks

 1999–2000 1,590 0.5 (0.3 – 0.8) 153,000

 2001–2002 1,864 0.7 (0.3 – 1.2) 201,000

 2005–2006 1,891 0.5 (0.3 – 0.7) 145,000

Non-Hispanic Whites

 1999–2000 2,456 § §

 2001–2002 3,455 0.2‡ (0.1 – 0.5) 398,000‡

 2005–2006 2,973 0.2‡ (0.1 – 0.5) 386,000‡

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 103103

Table 2.1.d.2. Serum vitamin A: Prevalence by survey cycle

Prevalence (in percent) of high serum vitamin A concentration (> 100 μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2002 and 2005–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 6 years and older

 1999–2000 7,102 1.3 (1.0 – 1.8) 3,312,000

 2001–2002 7,935 2.0 (1.6 – 2.5) 5,242,000

 2005–2006 7,254 2.1 (1.6 – 2.7) 5,573,000

Age group

3–5 years

 1999–2000 352 § §

 2001–2002 430 § §

6–11 years

 1999–2000 866 § §

 2001–2002 1,014 § §

 2005–2006 860 § §

12–19 years

 1999–2000 2,111 § §

 2001–2002 2,206 § §

 2005–2006 1,954 § §

20–39 years

 1999–2000 1,461 § §

 2001–2002 1,716 0.6‡ (0.2 – 1.3) 437,000‡

 2005–2006 1,688 1.1‡ (0.5 – 2.3) 847,000‡

40–59 years

 1999–2000 1,191 2.4 (1.4 – 4.0) 1,688,000

 2001–2002 1,474 2.9 (2.0 – 4.4) 2,222,000

 2005–2006 1,365 2.7 (1.8 – 3.9) 2,182,000

60 years and older

 1999–2000 1,473 3.2 (2.1 – 4.8) 1,381,000

 2001–2002 1,525 5.9 (4.3 – 8.0) 2,628,000

 2005–2006 1,387 4.8 (3.8 – 6.0) 2,301,000

Gender

(6 years and older)

Males

 1999–2000 3,450 1.4 (0.9 – 2.4) 1,741,000

 2001–2002 3,841 2.4 (1.9 – 3.0) 3,013,000

 2005–2006 3,547 2.5 (1.8 – 3.4) 3,265,000

Females

 1999–2000 3,652 1.2 (0.7 – 2.0) 1,570,000

 2001–2002 4,094 1.7 (1.2 – 2.4) 2,226,000

 2005–2006 3,707 1.7 (1.0 – 2.9) 2,306,000

Race/ethnicity

(6 years and older)

Mexican Americans

 1999–2000 2,410 § §

 2001–2002 1,991 § §

 2005–2006 1,844 0.5‡ (0.3 – 1.1) 129,000‡

Non-Hispanic Blacks

 1999–2000 1,590 1.2 (0.7 – 2.2) 376,000

 2001–2002 1,864 1.7‡ (0.8 – 3.7) 519,000‡

 2005–2006 1,891 1.1 (0.6 – 2.0) 348,000

Non-Hispanic Whites

 1999–2000 2,456 1.7 (1.2 – 2.4) 2,962,000

 2001–2002 3,455 2.4 (1.9 – 2.9) 4,296,000

 2005–2006 2,973 2.6 (2.0 – 3.5) 4,752,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
104

2nd 104 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.2.a.1. Serum retinyl palmitate: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 2.11 (2.05 – 2.17) < LOD < LOD 2.08 (1.99 – 2.17) 5.67 (5.35 – 6.03) 7.35 (6.93 – 7.96) 6,946 Age group 6–11 years 2.15 (2.01 – 2.29) < LOD < LOD 2.14 (1.93 – 2.27) 5.01 (4.70 – 5.81) 6.18 (5.67 – 8.84) 827 12–19 years 1.90 (1.84 – 1.97) < LOD < LOD 1.83 (1.74 – 1.94) 4.78 (4.51 – 5.37) 6.19 (5.77 – 6.77) 1,865 20–39 years 2.13 (2.04 – 2.23) < LOD < LOD 2.18 (2.03 – 2.29) 5.00 (4.67 – 5.36) 6.31 (5.70 – 7.62) 1,620 40–59 years 2.14 (2.04 – 2.25) < LOD < LOD 2.12 (2.00 – 2.24) 6.15 (5.46 – 6.80) 7.58 (6.74 – 9.10) 1,315 60 years and older 2.14 (2.01 – 2.28) < LOD < LOD 2.04 (1.88 – 2.23) 6.87 (6.04 – 8.01) 8.80 (7.86 – 11.7) 1,319 Gender Males 2.15 (2.08 – 2.23) < LOD < LOD 2.14 (2.04 – 2.24) 5.89 (5.50 – 6.32) 7.26 (6.78 – 8.26) 3,397 Females 2.07 (2.01 – 2.12) < LOD < LOD 2.01 (1.94 – 2.11) 5.51 (4.96 – 6.12) 7.45 (6.53 – 8.14) 3,549 Race/ethnicity Mexican Americans 1.85 (1.78 – 1.91) < LOD < LOD 1.78 (1.69 – 1.88) 4.77 (4.40 – 5.18) 5.69 (5.19 – 7.49) 1,746 Non-Hispanic Blacks 2.04 (1.90 – 2.19) < LOD < LOD 2.03 (1.84 – 2.20) 5.00 (4.65 – 5.76) 6.36 (5.70 – 7.56) 1,842 Non-Hispanic Whites 2.17 (2.10 – 2.25) < LOD < LOD 2.17 (2.04 – 2.27) 6.02 (5.60 – 6.49) 7.82 (7.04 – 8.74) 2,838 < LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.
6−11 12−19 20−39 40−59 60+ 

0 1 2 3 4 

Serum retinyl palmitate (μg/dL) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

4 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.2.a. Serum retinyl palmitate: Concentrations by age group 

Geometric Mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006 Serum retinyl palmitate Serum retinyl palmitate (μg/dL) (μg/dL) 0 1 2 3 4 0 1 2 3 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 105105
106 2nd 106 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.2.a.2. Serum retinyl palmitate: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 2.11 (2.05 – 2.17) < LOD 2.08 (1.99 – 2.17) 4.40 (4.28 – 4.54) 6,946

6–11 years 2.15 (2.01 – 2.29) < LOD 2.14 (1.93 – 2.27) 4.19 (4.02 – 4.62) 827

12–19 years 1.90 (1.84 – 1.97) < LOD 1.83 (1.74 – 1.94) 3.79 (3.60 – 4.10) 1,865

20–39 years 2.13 (2.04 – 2.23) < LOD 2.18 (2.03 – 2.29) 4.16 (3.86 – 4.43) 1,620

40–59 years 2.14 (2.04 – 2.25) < LOD 2.12 (2.00 – 2.24) 4.57 (4.23 – 5.15) 1,315

60 years and older 2.14 (2.01 – 2.28) < LOD 2.04 (1.88 – 2.23) 4.99 (4.54 – 5.60) 1,319

Males

Total, 6 years and older 2.15 (2.08 – 2.23) < LOD 2.14 (2.04 – 2.24) 4.52 (4.39 – 4.69) 3,397

6–11 years 2.26 (2.05 – 2.48) < LOD 2.22 (2.02 – 2.36) 4.56 (4.13 – 5.45) 411

12–19 years 1.93 (1.82 – 2.05) < LOD 1.85 (1.72 – 2.02) 3.84 (3.55 – 4.26) 935

20–39 years 2.24 (2.09 – 2.39) < LOD 2.30 (2.14 – 2.43) 4.42 (4.04 – 4.69) 714

40–59 years 2.15 (2.01 – 2.30) < LOD 2.14 (2.01 – 2.27) 4.66 (4.29 – 5.53) 650

60 years and older 2.14 (2.01 – 2.28) < LOD 2.03 (1.87 – 2.25) 5.04 (4.47 – 5.60) 687

Females

Total, 6 years and older 2.07 (2.01 – 2.12) < LOD 2.01 (1.94 – 2.11) 4.29 (4.13 – 4.44) 3,549

6–11 years 2.05 (1.86 – 2.25) < LOD 2.03 (1.81 – 2.25) 4.02 (3.76 – 4.41) 416

12–19 years 1.88 (1.80 – 1.95) < LOD 1.82 (1.69 – 1.92) 3.69 (3.44 – 4.31) 930

20–39 years 2.02 (1.94 – 2.11) < LOD 2.03 (1.91 – 2.18) 3.87 (3.65 – 4.31) 906

40–59 years 2.13 (2.03 – 2.24) < LOD 2.10 (1.97 – 2.24) 4.48 (4.00 – 5.50) 665

60 years and older 2.14 (1.97 – 2.33) < LOD 2.05 (1.78 – 2.31) 4.95 (4.36 – 6.43) 632

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

Table 2.2.a.3. Serum retinyl palmitate: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 1.85 (1.78 – 1.91) < LOD 1.78 (1.69 – 1.88) 3.84 (3.60 – 4.09) 1,746

6–11 years 1.79 (1.67 – 1.91) < LOD 1.68 (1.58 – 1.80) 3.66 (3.09 – 4.25) 275

12–19 years 1.65 (1.56 – 1.74) < LOD 1.62 (1.57 – 1.67) 3.11 (2.87 – 3.51) 614

20–39 years 1.90 (1.77 – 2.04) < LOD 1.87 (1.68 – 2.04) 3.94 (3.68 – 4.49) 432

40–59 years 1.89 (1.78 – 2.02) < LOD 1.81 (1.67 – 2.00) 4.08 (3.50 – 4.79) 233

60 years and older 1.95 (1.78 – 2.14) < LOD 1.79 (1.63 – 2.06) 4.57 (3.78 – 5.89) 192

Males

Total, 6 years and older 1.91 (1.80 – 2.03) < LOD 1.84 (1.69 – 2.00) 3.99 (3.70 – 4.70) 832

6–11 years 1.73 (1.56 – 1.91) < LOD 1.60 (1.51 – 1.79) 3.68 (2.85 – 5.04) 136

12–19 years 1.69 (1.56 – 1.83) < LOD 1.64 (1.56 – 1.75) 3.12 (2.70 – 3.94) 294

20–39 years 1.99 (1.74 – 2.27) < LOD 1.95 (1.67 – 2.27) 4.21 (3.82 – 5.31) 193

40–59 years 2.05 (1.86 – 2.26) < LOD 1.98 (1.55 – 2.44) 4.35 (3.76 – 5.44) 114

60 years and older 1.86 (1.56 – 2.22) < LOD† 1.76 (1.35 – 2.41) 4.45† (3.55 – 5.43) 95

Females

Total, 6 years and older 1.78 (1.70 – 1.85) < LOD 1.72 (1.63 – 1.83) 3.56 (3.44 – 3.71) 914

6–11 years 1.85 (1.70 – 2.02) < LOD 1.76 (1.63 – 1.94) 3.64 (3.14 – 4.87) 139

12–19 years 1.61 (1.52 – 1.70) < LOD 1.60 (1.47 – 1.69) 3.09 (2.79 – 3.66) 320

20–39 years 1.79 (1.63 – 1.98) < LOD 1.77 (1.53 – 2.03) 3.56 (3.32 – 3.89) 239

40–59 years 1.75 (1.63 – 1.88) < LOD 1.72 (1.52 – 1.95) 3.52 (3.24 – 4.47) 119

60 years and older 2.02 (1.77 – 2.32) < LOD† 1.79 (1.58 – 2.24) 4.59† (3.30 – 8.50) 97

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 107107

Table 2.2.a.4. Serum retinyl palmitate: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 2.04 (1.90 – 2.19) < LOD 2.03 (1.84 – 2.20) 4.13 (3.85 – 4.48) 1,842

6–11 years 2.49 (2.19 – 2.82) < LOD 2.49 (2.13 – 3.01) 4.82 (4.58 – 5.44) 238

12–19 years 2.03 (1.88 – 2.21) < LOD 1.99 (1.84 – 2.23) 4.05 (3.58 – 4.59) 643

20–39 years 2.12 (1.92 – 2.35) < LOD 2.10 (1.91 – 2.27) 4.23 (3.81 – 4.67) 363

40–59 years 1.96 (1.82 – 2.12) < LOD 1.94 (1.73 – 2.21) 3.88 (3.59 – 4.61) 326

60 years and older 1.77 (1.60 – 1.96) < LOD 1.65 (1.44 – 1.89) 3.95 (3.26 – 4.67) 272

Males

Total, 6 years and older 2.15 (1.99 – 2.32) < LOD 2.16 (2.00 – 2.30) 4.45 (3.88 – 5.02) 921

6–11 years 2.66 (2.34 – 3.03) < LOD 2.71 (2.35 – 2.96) 5.34 (4.54 – 6.33) 127

12–19 years 2.17 (1.98 – 2.38) < LOD 2.13 (1.88 – 2.36) 4.49 (3.67 – 5.39) 330

20–39 years 2.29 (2.05 – 2.56) < LOD 2.28 (2.05 – 2.56) 4.45 (3.73 – 5.85) 168

40–59 years 1.99 (1.80 – 2.21) < LOD 2.12 (1.69 – 2.30) 3.84 (3.42 – 7.34) 153

60 years and older 1.79 (1.59 – 2.01) < LOD 1.62 (1.32 – 1.99) 4.64 (3.40 – 5.35) 143

Females

Total, 6 years and older 1.95 (1.79 – 2.12) < LOD 1.92 (1.74 – 2.14) 3.93 (3.80 – 4.22) 921

6–11 years 2.32 (1.94 – 2.77) < LOD† 2.37 (1.87 – 2.87) 4.60† (4.24 – 5.12) 111

12–19 years 1.90 (1.71 – 2.12) < LOD 1.91 (1.65 – 2.19) 3.55 (3.39 – 4.26) 313

20–39 years 1.99 (1.75 – 2.25) < LOD 2.01 (1.73 – 2.24) 3.92 (3.70 – 4.67) 195

40–59 years 1.94 (1.76 – 2.14) < LOD 1.88 (1.69 – 2.11) 3.92 (3.61 – 4.47) 173

60 years and older 1.76 (1.52 – 2.03) < LOD 1.66 (1.43 – 2.02) 3.54 (3.07 – 4.22) 129

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.

Table 2.2.a.5. Serum retinyl palmitate: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 2.17 (2.10 – 2.25) < LOD 2.17 (2.04 – 2.27) 4.54 (4.39 – 4.71) 2,838

6–11 years 2.18 (1.97 – 2.41) < LOD 2.16 (1.87 – 2.30) 4.19 (3.82 – 4.82) 224

12–19 years 1.93 (1.84 – 2.03) < LOD 1.85 (1.70 – 2.01) 3.92 (3.56 – 4.47) 475

20–39 years 2.21 (2.07 – 2.36) < LOD 2.30 (2.12 – 2.44) 4.32 (3.85 – 4.66) 676

40–59 years 2.20 (2.08 – 2.33) < LOD 2.21 (2.02 – 2.34) 4.66 (4.33 – 5.45) 658

60 years and older 2.20 (2.05 – 2.37) < LOD 2.12 (1.91 – 2.35) 5.16 (4.63 – 5.86) 805

Males

Total, 6 years and older 2.22 (2.12 – 2.32) < LOD 2.21 (2.08 – 2.30) 4.66 (4.45 – 4.99) 1,407

6–11 years 2.28 (1.97 – 2.63) < LOD† 2.22 (1.95 – 2.61) 4.52† (3.80 – 5.92) 107

12–19 years 1.94 (1.79 – 2.10) < LOD 1.87 (1.68 – 2.10) 3.80 (3.40 – 4.67) 245

20–39 years 2.35 (2.14 – 2.57) < LOD 2.40 (2.22 – 2.59) 4.49 (4.09 – 5.04) 293

40–59 years 2.21 (2.06 – 2.36) < LOD 2.20 (2.02 – 2.35) 4.77 (4.35 – 6.02) 339

60 years and older 2.20 (2.04 – 2.38) < LOD 2.10 (1.89 – 2.36) 5.16 (4.50 – 5.79) 423

Females

Total, 6 years and older 2.13 (2.05 – 2.21) < LOD 2.13 (1.96 – 2.26) 4.41 (4.25 – 4.65) 1,431

6–11 years 2.07 (1.77 – 2.43) < LOD 2.10 (1.75 – 2.39) 4.05 (3.50 – 4.51) 117

12–19 years 1.92 (1.81 – 2.04) < LOD 1.81 (1.67 – 1.98) 3.98 (3.30 – 4.57) 230

20–39 years 2.08 (1.94 – 2.23) < LOD 2.21 (1.91 – 2.36) 4.07 (3.57 – 4.65) 383

40–59 years 2.20 (2.06 – 2.34) < LOD 2.21 (1.97 – 2.40) 4.54 (4.05 – 5.85) 319

60 years and older 2.20 (1.99 – 2.42) < LOD 2.15 (1.80 – 2.41) 5.15 (4.45 – 6.71) 382

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.
108 2nd 108 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.2.b. Serum retinyl palmitate: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2002 and 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 1.23 (1.04 – 1.46) < LOD 1.47 (1.27 – 1.70) 4.95 (4.58 – 5.83) 5,589

 2001–2002 1.92 (1.83 – 2.02) .690 (.537 – .696) 1.93 (1.85 – 2.01) 5.49 (5.16 – 5.86) 7,641

 2005–2006 2.11 (2.05 – 2.17) < LOD 2.08 (1.99 – 2.17) 5.67 (5.35 – 6.03) 6,946

Age group

3–5 years

 1999–2000 1.46 (1.16 – 1.84) < LOD 1.67 (1.33 – 1.97) 5.39 (4.82 – 8.78) 278

 2001–2002 1.88 (1.71 – 2.06) .482 (< LOD – .710) 1.82 (1.69 – 2.02) 5.62 (4.79 – 8.77) 412

6–11 years

 1999–2000 1.33 (1.07 – 1.67) < LOD 1.64 (1.29 – 2.02) 5.75 (4.55 – 8.88) 651

 2001–2002 2.02 (1.90 – 2.15) .700 (.462 – .801) 2.15 (2.03 – 2.25) 5.32 (4.79 – 5.85) 967

 2005–2006 2.15 (2.01 – 2.29) < LOD 2.14 (1.93 – 2.27) 5.01 (4.70 – 5.81) 827

12–19 years

 1999–2000 1.17 (.963 – 1.41) < LOD 1.41 (1.12 – 1.68) 4.11 (3.71 – 4.77) 1,620

 2001–2002 1.71 (1.61 – 1.80) .560 (.500 – .692) 1.77 (1.66 – 1.87) 4.21 (3.98 – 4.47) 2,122

 2005–2006 1.90 (1.84 – 1.97) < LOD 1.83 (1.74 – 1.94) 4.78 (4.51 – 5.37) 1,865

20–39 years

 1999–2000 1.14 (.928 – 1.39) < LOD 1.40 (1.21 – 1.62) 4.58 (4.14 – 5.67) 1,201

 2001–2002 1.91 (1.77 – 2.06) .643 (.543 – .720) 1.91 (1.79 – 2.03) 5.14 (4.65 – 5.79) 1,655

 2005–2006 2.13 (2.04 – 2.23) < LOD 2.18 (2.03 – 2.29) 5.00 (4.67 – 5.36) 1,620

40–59 years

 1999–2000 1.30 (1.06 – 1.59) < LOD 1.55 (1.30 – 1.84) 5.49 (4.61 – 6.83) 959

 2001–2002 1.99 (1.87 – 2.11) .623 (.529 – .698) 1.96 (1.89 – 2.06) 5.70 (5.19 – 6.53) 1,429

 2005–2006 2.14 (2.04 – 2.25) < LOD 2.12 (2.00 – 2.24) 6.15 (5.46 – 6.80) 1,315

60 years and older

 1999–2000 1.34 (1.11 – 1.62) < LOD 1.54 (1.29 – 1.89) 5.78 (4.87 – 6.47) 1,158

 2001–2002 1.96 (1.82 – 2.11) .522 (.453 – .580) 1.91 (1.75 – 2.13) 6.79 (6.11 – 7.83) 1,468

 2005–2006 2.14 (2.01 – 2.28) < LOD 2.04 (1.88 – 2.23) 6.87 (6.04 – 8.01) 1,319

Gender

(6 years and older)

Males

 1999–2000 1.38 (1.17 – 1.63) < LOD 1.61 (1.40 – 1.82) 5.22 (4.65 – 5.94) 2,676

 2001–2002 2.01 (1.90 – 2.12) .636 (.544 – .687) 2.01 (1.91 – 2.12) 5.71 (5.31 – 6.20) 3,698

 2005–2006 2.15 (2.08 – 2.23) < LOD 2.14 (2.04 – 2.24) 5.89 (5.50 – 6.32) 3,397

Females

 1999–2000 1.11 (.922 – 1.33) < LOD 1.36 (1.16 – 1.61) 4.79 (4.47 – 5.80) 2,913

 2001–2002 1.85 (1.76 – 1.95) .582 (.515 – .695) 1.84 (1.75 – 1.92) 5.11 (4.78 – 5.68) 3,943

 2005–2006 2.07 (2.01 – 2.12) < LOD 2.01 (1.94 – 2.11) 5.51 (4.96 – 6.12) 3,549

Race/ethnicity

(6 years and older)

Mexican Americans

 1999–2000 .759 (.635 – .906) < LOD .945 (.808 – 1.14) 3.69 (3.32 – 4.35) 1,463

 2001–2002 1.62 (1.47 – 1.78) .503 (.398 – .575) 1.65 (1.50 – 1.85) 4.28 (3.95 – 4.80) 1,980

 2005–2006 1.85 (1.78 – 1.91) < LOD 1.78 (1.69 – 1.88) 4.77 (4.40 – 5.18) 1,746

Non-Hispanic Blacks

 1999–2000 1.18 (.848 – 1.64) < LOD 1.48 (1.07 – 1.99) 5.06 (4.41 – 5.81) 1,422

 2001–2002 1.92 (1.82 – 2.02) .628 (.390 – .709) 1.96 (1.88 – 2.06) 5.44 (4.71 – 6.44) 1,734

 2005–2006 2.04 (1.90 – 2.19) < LOD 2.03 (1.84 – 2.20) 5.00 (4.65 – 5.76) 1,842

Non-Hispanic Whites

 1999–2000 1.32 (1.08 – 1.60) < LOD 1.57 (1.33 – 1.84) 5.12 (4.60 – 6.48) 2,121

 2001–2002 1.97 (1.87 – 2.08) .636 (.584 – .684) 1.95 (1.86 – 2.06) 5.57 (5.14 – 5.99) 3,318

 2005–2006 2.17 (2.10 – 2.25) < LOD 2.17 (2.04 – 2.27) 6.02 (5.60 – 6.49) 2,838

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.
Figure 2.2.b. Serum retinyl palmitate: Concentrations by survey cycle 

Selected percentiles in μg/dL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2002 and 2005–2006 

10 

8 

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( 

( 

( ( 

( ( 

( ( 

( 

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( 

( 

( 

( 

( 

( ( 

( 

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( 

( 

5th Percentile 50th Percentile 95th Percentile

6 

4 

2 

2.5 

2.0 

1.5 

1.0 

0.5 

0.8 

0.7 

0.6 

0.5 

0.4 

0.3 

( 

( 

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( 

( ( 

99−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−0699−0001−0205−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) (6+y) (6+y) (6+y) (6+y) (6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 109109
110

2nd 110 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.3.a.1. Serum retinyl stearate: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older * < LOD < LOD < LOD 1.31 (1.23 – 1.48) 1.95 (1.79 – 2.09) 6,698 Age group 6–11 years * < LOD < LOD < LOD 1.33 (1.08 – 1.97) 1.97 (1.65 – 4.08) 792 12–19 years * < LOD < LOD < LOD .911 (.743 – 1.14) 1.48 (1.18 – 2.00) 1,801 20–39 years * < LOD < LOD < LOD .947 (.850 – 1.09) 1.32 (1.14 – 1.76) 1,555 40–59 years * < LOD < LOD < LOD 1.35 (1.23 – 1.63) 2.00 (1.68 – 2.31) 1,262 60 years and older * < LOD < LOD < LOD 1.93 (1.59 – 2.58) 2.77 (2.26 – 3.58) 1,288 Gender Males * < LOD < LOD < LOD 1.40 (1.29 – 1.54) 1.94 (1.86 – 2.05) 3,276 Females * < LOD < LOD < LOD 1.25 (1.09 – 1.48) 1.99 (1.62 – 2.34) 3,422 Race/ethnicity Mexican Americans * < LOD < LOD < LOD .933 (.792 – 1.19) 1.35 (1.08 – 2.07) 1,739 Non-Hispanic Blacks * < LOD < LOD < LOD .896 (.829 – 1.10) 1.38 (1.10 – 1.71) 1,699 Non-Hispanic Whites * < LOD < LOD < LOD 1.50 (1.36 – 1.64) 2.06 (1.93 – 2.36) 2,747 < LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. * Not calculated. Proportion of results below limit of detection was too high to provide a valid result.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 111111

No serum retinyl stearate figure for concentrations by age group is presented because the

geometric means were not calculated due to the proportion of results below the limit of

detection being too high for valid results (see Table 2.3.a.1).
112 2nd 112 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.3.a.2. Serum retinyl stearate: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older * < LOD < LOD .894 (.794 – 1.02) 6,698

6–11 years * < LOD < LOD .972 (.730 – 1.21) 792

12–19 years * < LOD < LOD < LOD 1,801

20–39 years * < LOD < LOD < LOD 1,555

40–59 years * < LOD < LOD .944 (.810 – 1.16) 1,262

60 years and older * < LOD < LOD 1.32 (1.13 – 1.58) 1,288

Males

Total, 6 years and older * < LOD < LOD .964 (.871 – 1.08) 3,276

6–11 years * < LOD < LOD 1.03 (< LOD – 1.76) 394

12–19 years * < LOD < LOD < LOD 898

20–39 years * < LOD < LOD .813 (.709 – .968) 682

40–59 years * < LOD < LOD .993 (.842 – 1.17) 624

60 years and older * < LOD < LOD 1.33 (1.16 – 1.53) 678

Females

Total, 6 years and older * < LOD < LOD .839 (.741 – .960) 3,422

6–11 years * < LOD < LOD .896 (< LOD – 1.17) 398

12–19 years * < LOD < LOD < LOD 903

20–39 years * < LOD < LOD < LOD 873

40–59 years * < LOD < LOD .903 (.764 – 1.21) 638

60 years and older * < LOD < LOD 1.32 (1.06 – 1.74) 610

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.

Table 2.3.a.3. Serum retinyl stearate: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older * < LOD < LOD < LOD 1,739

6–11 years * < LOD < LOD < LOD 272

12–19 years * < LOD < LOD < LOD 604

20–39 years * < LOD < LOD < LOD 428

40–59 years * < LOD < LOD .766 (< LOD – 1.23) 238

60 years and older * < LOD < LOD .902 (.707 – 1.32) 197

Males

Total, 6 years and older * < LOD < LOD .736 (< LOD – .877) 832

6–11 years * < LOD < LOD < LOD 135

12–19 years * < LOD < LOD < LOD 290

20–39 years * < LOD < LOD .700 (< LOD – .965) 190

40–59 years * < LOD < LOD .851 (< LOD – 1.95) 118

60 years and older * < LOD† < LOD .780† (< LOD – 3.26) 99

Females

Total, 6 years and older * < LOD < LOD < LOD 907

6–11 years * < LOD < LOD < LOD 137

12–19 years * < LOD < LOD < LOD 314

20–39 years * < LOD < LOD < LOD 238

40–59 years * < LOD < LOD < LOD 120

60 years and older * < LOD† < LOD 1.02† (< LOD – 1.97) 98

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 113113

Table 2.3.a.4. Serum retinyl stearate: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older * < LOD < LOD < LOD 1,699

6–11 years * < LOD < LOD < LOD 219

12–19 years * < LOD < LOD < LOD 597

20–39 years * < LOD < LOD < LOD 322

40–59 years * < LOD < LOD .781 (< LOD – .931) 301

60 years and older * < LOD < LOD .770 (< LOD – 1.39) 260

Males

Total, 6 years and older * < LOD < LOD .746 (< LOD – .868) 849

6–11 years * < LOD < LOD < LOD 118

12–19 years * < LOD < LOD < LOD 300

20–39 years * < LOD < LOD < LOD 152

40–59 years * < LOD < LOD .813 (< LOD – 1.06) 141

60 years and older * < LOD < LOD 1.06 (< LOD – 1.55) 138

Females

Total, 6 years and older * < LOD < LOD < LOD 850

6–11 years * < LOD† < LOD < LOD† 101

12–19 years * < LOD < LOD < LOD 297

20–39 years * < LOD < LOD < LOD 170

40–59 years * < LOD < LOD .701 (< LOD – .962) 160

60 years and older * < LOD < LOD < LOD 122

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.

† Estimate is subject to greater uncertainty due to small cell size.

Table 2.3.a.5. Serum retinyl stearate: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older * < LOD < LOD 1.01 (.932 – 1.10) 2,747

6–11 years * < LOD < LOD 1.06 (.756 – 1.99) 212

12–19 years * < LOD < LOD < LOD 465

20–39 years * < LOD < LOD .727 (< LOD – .878) 660

40–59 years * < LOD < LOD 1.00 (.869 – 1.20) 627

60 years and older * < LOD < LOD 1.40 (1.17 – 1.73) 783

Males

Total, 6 years and older * < LOD < LOD 1.09 (.967 – 1.18) 1,370

6–11 years * < LOD† < LOD 1.09† (< LOD – 7.58) 103

12–19 years * < LOD < LOD .740 (< LOD – 1.05) 244

20–39 years * < LOD < LOD .927 (.740 – 1.16) 283

40–59 years * < LOD < LOD 1.07 (.862 – 1.24) 324

60 years and older * < LOD < LOD 1.39 (1.19 – 1.65) 416

Females

Total, 6 years and older * < LOD < LOD .948 (.855 – 1.07) 1,377

6–11 years * < LOD† < LOD 1.04† (.755 – 2.95) 109

12–19 years * < LOD < LOD < LOD 221

20–39 years * < LOD < LOD < LOD 377

40–59 years * < LOD < LOD .953 (.798 – 1.31) 303

60 years and older * < LOD < LOD 1.41 (1.08 – 2.01) 367

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.

† Estimate is subject to greater uncertainty due to small cell size.
114 2nd 114 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.3.b. Serum retinyl stearate: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2002 and 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 * < LOD < LOD 1.12 (.983 – 1.44) 4,148

 2001–2002 * < LOD < LOD 1.08 (.988 – 1.19) 7,690

 2005–2006 * < LOD < LOD 1.31 (1.23 – 1.48) 6,698

Age group

3–5 years

 1999–2000 * < LOD† < LOD 2.43† (1.72 – 3.65) 212

 2001–2002 * < LOD < LOD 1.75 (1.37 – 3.49) 416

6–11 years

 1999–2000 * < LOD < LOD 1.74 (1.09 – 10.3) 434

 2001–2002 * < LOD < LOD 1.14 (.964 – 1.34) 981

 2005–2006 * < LOD < LOD 1.33 (1.08 – 1.97) 792

12–19 years

 1999–2000 * < LOD < LOD .829 (< LOD – 1.30) 1,194

 2001–2002 * < LOD < LOD < LOD 2,145

 2005–2006 * < LOD < LOD .911 (.743 – 1.14) 1,801

20–39 years

 1999–2000 * < LOD < LOD .928 (.651 – 1.36) 872

 2001–2002 * < LOD < LOD .721 (.693 – .893) 1,658

 2005–2006 * < LOD < LOD .947 (.850 – 1.09) 1,555

40–59 years

 1999–2000 * < LOD < LOD 1.32 (.944 – 2.40) 716

 2001–2002 * < LOD < LOD 1.15 (1.04 – 1.46) 1,422

 2005–2006 * < LOD < LOD 1.35 (1.23 – 1.63) 1,262

60 years and older

 1999–2000 * < LOD < LOD 1.83 (1.39 – 2.90) 932

 2001–2002 * < LOD < LOD 1.77 (1.52 – 2.08) 1,484

 2005–2006 * < LOD < LOD 1.93 (1.59 – 2.58) 1,288

Gender

(6 years and older)

Males

 1999–2000 * < LOD < LOD 1.13 (.987 – 1.66) 2,008

 2001–2002 * < LOD < LOD 1.19 (1.09 – 1.42) 3,710

 2005–2006 * < LOD < LOD 1.40 (1.29 – 1.54) 3,276

Females

 1999–2000 * < LOD < LOD 1.10 (.951 – 1.42) 2,140

 2001–2002 * < LOD < LOD .953 (.856 – 1.09) 3,980

 2005–2006 * < LOD < LOD 1.25 (1.09 – 1.48) 3,422

Race/ethnicity

(6 years and older)

Mexican Americans

 1999–2000 * < LOD < LOD .695 (< LOD – 2.14) 1,002

 2001–2002 * < LOD < LOD .587 (< LOD – .880) 1,921

 2005–2006 * < LOD < LOD .933 (.792 – 1.19) 1,739

Non-Hispanic Blacks

 1999–2000 * < LOD < LOD .962 (.590 – 15.0) 1,060

 2001–2002 * < LOD < LOD .733 (.619 – .963) 1,827

 2005–2006 * < LOD < LOD .896 (.829 – 1.10) 1,699

Non-Hispanic Whites

 1999–2000 * < LOD < LOD 1.27 (1.00 – 1.81) 1,608

 2001–2002 * < LOD < LOD 1.13 (1.02 – 1.30) 3,331

 2005–2006 * < LOD < LOD 1.50 (1.36 – 1.64) 2,747

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.

† Estimate is subject to greater uncertainty due to cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 115115

2

4

6

8

10

5th Percentile

Total

(6+y)

99−0001−0205−06

3−5y

99−0001−0205−06

6−11y

99−0001−0205−06

12−19y 99−00 01−02

05−06

20+y

99−0001−0205−06

Males

(6+y)

99−0001−0205−06

Females

(6+y)

99−0001−0205−06

MA

(6+y)

99−0001−0205−06

NHB

(6+y)

99−0001−0205−06

NHW

(6+y)

99−0001−0205−06

2

4

6

8

10

50th Percentile

0

5

10

15

95th Percentile

Figure 2.3.b. Serum retinyl stearate: Concentrations by survey cycle

Selected percentiles in μg/dL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2002 and 2005–2006

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table.
116

2nd 116 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.4.a.1. Serum vitamin E: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 1,090 (1,070 – 1,120) 578 (563 – 587) 631 (620 – 642) 1,060 (1,030 – 1,080) 2,090 (2,010 – 2,180) 2,460 (2,310 – 2,600) 7,254 Age group 6–11 years 820 (800 – 841) 546 (518 – 573) 583 (563 – 601) 806 (788 – 826) 1,200 (1,120 – 1,370) 1,360 (1,230 – 1,510) 860 12–19 years 770 (757 – 783) 497 (466 – 519) 527 (516 – 541) 759 (749 – 767) 1,160 (1,130 – 1,200) 1,320 (1,240 – 1,450) 1,954 20–39 years 1,020 (998 – 1,040) 590 (559 – 619) 645 (621 – 668) 1,000 (980 – 1,020) 1,730 (1,620 – 1,900) 1,940 (1,810 – 2,380) 1,688 40–59 years 1,230 (1,190 – 1,260) 702 (656 – 721) 749 (724 – 769) 1,200 (1,160 – 1,240) 2,210 (2,080 – 2,400) 2,510 (2,260 – 3,110) 1,365 60 years and older 1,400 (1,360 – 1,440) 704 (611 – 750) 783 (733 – 835) 1,390 (1,330 – 1,430) 2,600 (2,510 – 2,660) 2,900 (2,710 – 3,130) 1,387 Gender Males 1,060 (1,040 – 1,090) 559 (543 – 575) 610 (594 – 625) 1,030 (1,010 – 1,070) 2,010 (1,930 – 2,090) 2,360 (2,160 – 2,520) 3,547 Females 1,120 (1,090 – 1,140) 596 (585 – 612) 653 (639 – 664) 1,080 (1,050 – 1,100) 2,170 (2,080 – 2,260) 2,510 (2,370 – 2,660) 3,707 Race/ethnicity Mexican Americans 1,010 (980 – 1,040) 581 (553 – 599) 623 (602 – 637) 976 (945 – 1,000) 1,790 (1,750 – 1,870) 2,120 (1,960 – 2,330) 1,844 Non-Hispanic Blacks 933 (915 – 951) 548 (530 – 559) 588 (581 – 601) 903 (884 – 918) 1,660 (1,560 – 1,750) 1,800 (1,740 – 2,080) 1,891 Non-Hispanic Whites 1,140 (1,110 – 1,160) 584 (566 – 596) 643 (624 – 658) 1,110 (1,080 – 1,140) 2,170 (2,090 – 2,270) 2,520 (2,420 – 2,690) 2,973
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 117117

6−11 12−19 20−39 40−59 60+

0 500 1000 1500 2000

Serum vitamin E

(μg/dL)

Overall

6−11 12−19 20−39 40−59 60+

Mexican Americans

Females

Males

6−11 12−19 20−39 40−59 60+

0 500 1000 1500 2000

Non−Hispanic Blacks

Serum vitamin E

(μg/dL)

6−11 12−19 20−39 40−59 60+

Non−Hispanic Whites

6−11 12−19 20−39 40−59 60+

0 500 1000 1500 2000

Serum vitamin E

(μg/dL)

Females

Age (years)

6−11 12−19 20−39 40−59 60+

Males

Age (years)

Mexican

 Americans

Non−Hispanic

 Blacks

Non−Hispanic

 Whites

Figure 2.4.a. Serum vitamin E: Concentrations by age group

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006
118 2nd 118 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.4.a.2. Serum vitamin E: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 1,090 (1,070 – 1,120) 702 (686 – 716) 1,060 (1,030 – 1,080) 1,790 (1,730 – 1,840) 7,254

6–11 years 820 (800 – 841) 629 (621 – 638) 806 (788 – 826) 1,070 (1,040 – 1,180) 860

12–19 years 770 (757 – 783) 578 (557 – 587) 759 (749 – 767) 1,050 (1,000 – 1,070) 1,954

20–39 years 1,020 (998 – 1,040) 710 (683 – 727) 1,000 (980 – 1,020) 1,520 (1,410 – 1,610) 1,688

40–59 years 1,230 (1,190 – 1,260) 824 (799 – 848) 1,200 (1,160 – 1,240) 1,870 (1,790 – 2,040) 1,365

60 years and older 1,400 (1,360 – 1,440) 897 (828 – 949) 1,390 (1,330 – 1,430) 2,190 (2,130 – 2,270) 1,387

Males

Total, 6 years and older 1,060 (1,040 – 1,090) 682 (664 – 704) 1,030 (1,010 – 1,070) 1,730 (1,640 – 1,770) 3,547

6–11 years 817 (789 – 847) 629 (593 – 642) 807 (766 – 843) 1,070 (1,030 – 1,180) 427

12–19 years 753 (739 – 768) 553 (527 – 580) 747 (733 – 759) 1,030 (986 – 1,070) 980

20–39 years 1,030 (1,010 – 1,050) 699 (671 – 728) 1,010 (984 – 1,030) 1,570 (1,440 – 1,730) 738

40–59 years 1,210 (1,180 – 1,250) 798 (767 – 848) 1,190 (1,160 – 1,240) 1,820 (1,740 – 1,950) 673

60 years and older 1,300 (1,230 – 1,370) 827 (762 – 887) 1,290 (1,220 – 1,330) 2,070 (1,950 – 2,310) 729

Females

Total, 6 years and older 1,120 (1,090 – 1,140) 717 (705 – 723) 1,080 (1,050 – 1,100) 1,840 (1,790 – 1,910) 3,707

6–11 years 823 (792 – 856) 628 (608 – 647) 805 (784 – 837) 1,090 (1,020 – 1,230) 433

12–19 years 788 (772 – 804) 594 (570 – 611) 771 (755 – 788) 1,050 (991 – 1,120) 974

20–39 years 1,010 (981 – 1,040) 717 (679 – 738) 997 (956 – 1,030) 1,470 (1,360 – 1,580) 950

40–59 years 1,240 (1,200 – 1,290) 841 (818 – 860) 1,210 (1,160 – 1,240) 1,920 (1,820 – 2,120) 692

60 years and older 1,490 (1,440 – 1,540) 966 (926 – 987) 1,500 (1,430 – 1,540) 2,260 (2,190 – 2,470) 658

Table 2.4.a.3. Serum vitamin E: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 1,010 (980 – 1,040) 671 (656 – 695) 976 (945 – 1,000) 1,580 (1,530 – 1,630) 1,844

6–11 years 793 (770 – 816) 623 (599 – 644) 779 (755 – 800) 1,010 (977 – 1,110) 295

12–19 years 760 (740 – 781) 587 (578 – 597) 750 (723 – 773) 991 (970 – 1,050) 646

20–39 years 1,020 (991 – 1,060) 727 (676 – 755) 997 (968 – 1,020) 1,520 (1,420 – 1,640) 449

40–59 years 1,240 (1,200 – 1,280) 836 (808 – 861) 1,220 (1,160 – 1,270) 1,790 (1,730 – 1,950) 246

60 years and older 1,360 (1,250 – 1,470) 913 (816 – 996) 1,300 (1,240 – 1,370) 2,000 (1,720 – 3,120) 208

Males

Total, 6 years and older 1,010 (970 – 1,050) 671 (640 – 701) 972 (925 – 999) 1,570 (1,510 – 1,610) 883

6–11 years 786 (762 – 811) 622 (598 – 643) 763 (745 – 802) 989 (962 – 1,060) 145

12–19 years 748 (718 – 778) 591 (573 – 603) 733 (690 – 775) 978 (930 – 1,060) 313

20–39 years 1,040 (1,010 – 1,080) 753 (703 – 772) 990 (967 – 1,020) 1,590 (1,460 – 1,700) 198

40–59 years 1,270 (1,190 – 1,350) 863 (814 – 908) 1,260 (1,140 – 1,350) 1,670 (1,610 – 2,030) 122

60 years and older 1,260 (1,140 – 1,390) 845† (650 – 931) 1,240 (1,100 – 1,340) 1,970† (1,570 – 3,130) 105

Females

Total, 6 years and older 1,010 (984 – 1,030) 670 (649 – 696) 985 (949 – 1,020) 1,610 (1,530 – 1,670) 961

6–11 years 800 (763 – 838) 625 (514 – 658) 787 (760 – 799) 1,050 (958 – 1,240) 150

12–19 years 774 (750 – 798) 583 (570 – 597) 763 (748 – 784) 1,020 (960 – 1,090) 333

20–39 years 1,000 (955 – 1,050) 700 (634 – 742) 1,000 (947 – 1,060) 1,490 (1,340 – 1,650) 251

40–59 years 1,210 (1,170 – 1,260) 808 (778 – 859) 1,200 (1,110 – 1,240) 1,840 (1,710 – 2,100) 124

60 years and older 1,450 (1,300 – 1,610) 1,000† (872 – 1,090) 1,410 (1,240 – 1,540) 2,040† (1,720 – 4,610) 103

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 119119

Table 2.4.a.4. Serum vitamin E: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 933 (915 – 951) 644 (630 – 656) 903 (884 – 918) 1,400 (1,360 – 1,470) 1,891

6–11 years 771 (743 – 801) 587 (550 – 634) 762 (735 – 800) 1,010 (941 – 1,090) 240

12–19 years 731 (715 – 748) 575 (551 – 591) 727 (717 – 736) 945 (913 – 990) 665

20–39 years 926 (896 – 957) 665 (620 – 686) 893 (865 – 933) 1,340 (1,250 – 1,450) 368

40–59 years 1,040 (1,010 – 1,070) 736 (688 – 779) 1,010 (998 – 1,050) 1,540 (1,420 – 1,670) 335

60 years and older 1,110 (1,060 – 1,160) 752 (709 – 791) 1,080 (993 – 1,150) 1,680 (1,560 – 1,780) 283

Males

Total, 6 years and older 915 (897 – 933) 636 (618 – 651) 882 (870 – 895) 1,390 (1,310 – 1,460) 949

6–11 years 768 (740 – 799) 588 (558 – 634) 752 (726 – 799) 1,030 (928 – 1,110) 128

12–19 years 732 (714 – 751) 582 (558 – 606) 727 (712 – 737) 940 (904 – 981) 343

20–39 years 937 (888 – 989) 650 (603 – 687) 896 (862 – 939) 1,400 (1,240 – 1,670) 170

40–59 years 1,010 (972 – 1,050) 718 (632 – 743) 988 (960 – 1,020) 1,520 (1,390 – 1,640) 156

60 years and older 1,050 (1,000 – 1,100) 726 (580 – 770) 980 (894 – 1,080) 1,680 (1,410 – 2,250) 152

Females

Total, 6 years and older 949 (923 – 976) 651 (638 – 673) 916 (897 – 944) 1,450 (1,350 – 1,560) 942

6–11 years 775 (735 – 817) 579 (400 – 643) 776 (746 – 803) 1,000 (931 – 1,140) 112

12–19 years 731 (706 – 757) 567 (517 – 596) 726 (712 – 750) 957 (906 – 1,050) 322

20–39 years 917 (893 – 941) 677 (613 – 704) 892 (862 – 925) 1,270 (1,190 – 1,490) 198

40–59 years 1,070 (1,030 – 1,110) 761 (707 – 808) 1,040 (1,000 – 1,110) 1,540 (1,400 – 1,740) 179

60 years and older 1,150 (1,080 – 1,230) 774 (650 – 848) 1,130 (1,040 – 1,230) 1,670 (1,560 – 1,770) 131

Table 2.4.a.5. Serum vitamin E: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 1,140 (1,110 – 1,160) 718 (706 – 729) 1,110 (1,080 – 1,140) 1,870 (1,810 – 1,940) 2,973

6–11 years 840 (815 – 866) 627 (612 – 642) 826 (805 – 854) 1,120 (1,060 – 1,260) 231

12–19 years 779 (761 – 797) 579 (544 – 589) 765 (751 – 784) 1,060 (1,010 – 1,140) 499

20–39 years 1,040 (1,010 – 1,070) 711 (671 – 741) 1,030 (1,000 – 1,060) 1,550 (1,410 – 1,710) 714

40–59 years 1,260 (1,220 – 1,300) 846 (817 – 866) 1,230 (1,190 – 1,260) 1,910 (1,800 – 2,100) 683

60 years and older 1,430 (1,390 – 1,480) 919 (856 – 976) 1,430 (1,390 – 1,480) 2,230 (2,170 – 2,330) 846

Males

Total, 6 years and older 1,100 (1,070 – 1,130) 703 (671 – 725) 1,080 (1,050 – 1,120) 1,770 (1,740 – 1,850) 1,472

6–11 years 839 (801 – 879) 629 (562 – 680) 830 (791 – 880) 1,080 (1,030 – 1,300) 112

12–19 years 757 (737 – 778) 542 (523 – 572) 754 (730 – 783) 1,060 (1,000 – 1,110) 254

20–39 years 1,040 (1,020 – 1,070) 687 (640 – 735) 1,030 (1,020 – 1,060) 1,590 (1,430 – 1,770) 309

40–59 years 1,240 (1,200 – 1,270) 818 (769 – 865) 1,230 (1,180 – 1,260) 1,840 (1,750 – 2,040) 351

60 years and older 1,330 (1,240 – 1,420) 862 (733 – 930) 1,300 (1,250 – 1,360) 2,100 (1,970 – 2,460) 446

Females

Total, 6 years and older 1,170 (1,150 – 1,200) 727 (718 – 746) 1,140 (1,100 – 1,170) 1,930 (1,870 – 2,050) 1,501

6–11 years 841 (792 – 892) 624 (597 – 656) 819 (774 – 878) 1,160 (1,050 – 1,470) 119

12–19 years 803 (780 – 827) 601 (562 – 641) 779 (750 – 805) 1,060 (985 – 1,200) 245

20–39 years 1,040 (1,000 – 1,080) 720 (699 – 754) 1,020 (978 – 1,060) 1,510 (1,360 – 1,630) 405

40–59 years 1,270 (1,230 – 1,320) 862 (842 – 894) 1,240 (1,190 – 1,280) 2,000 (1,850 – 2,190) 332

60 years and older 1,530 (1,480 – 1,590) 985 (964 – 1,020) 1,530 (1,470 – 1,590) 2,320 (2,240 – 2,500) 400
120 2nd 120 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.4.b. Serum vitamin E: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2002 and 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 1,070 (1,040 – 1,110) 597 (575 – 612) 1,010 (986 – 1,040) 2,350 (2,280 – 2,500) 7,054

 2001–2002 1,110 (1,090 – 1,140) 637 (623 – 649) 1,050 (1,010 – 1,090) 2,380 (2,260 – 2,520) 7,935

 2005–2006 1,090 (1,070 – 1,120) 631 (620 – 642) 1,060 (1,030 – 1,080) 2,090 (2,010 – 2,180) 7,254

Age group

3–5 years

 1999–2000 785 (752 – 820) 559 (514 – 585) 772 (734 – 829) 1,160 (1,120 – 1,400) 347

 2001–2002 814 (780 – 850) 577 (553 – 601) 796 (760 – 824) 1,200 (1,090 – 1,670) 430

6–11 years

 1999–2000 783 (754 – 814) 545 (519 – 557) 781 (749 – 824) 1,130 (1,090 – 1,210) 859

 2001–2002 804 (788 – 821) 576 (560 – 591) 798 (780 – 819) 1,140 (1,090 – 1,220) 1,014

 2005–2006 820 (800 – 841) 583 (563 – 601) 806 (788 – 826) 1,200 (1,120 – 1,370) 860

12–19 years

 1999–2000 736 (717 – 756) 513 (491 – 530) 729 (712 – 744) 1,100 (1,020 – 1,240) 2,108

 2001–2002 782 (768 – 796) 550 (540 – 559) 771 (761 – 786) 1,170 (1,110 – 1,280) 2,206

 2005–2006 770 (757 – 783) 527 (516 – 541) 759 (749 – 767) 1,160 (1,130 – 1,200) 1,954

20–39 years

 1999–2000 973 (952 – 995) 615 (590 – 630) 938 (911 – 972) 1,750 (1,640 – 1,860) 1,452

 2001–2002 1,010 (987 – 1,030) 646 (627 – 661) 979 (960 – 1,000) 1,720 (1,620 – 1,880) 1,716

 2005–2006 1,020 (998 – 1,040) 645 (621 – 668) 1,000 (980 – 1,020) 1,730 (1,620 – 1,900) 1,688

40–59 years

 1999–2000 1,300 (1,250 – 1,360) 753 (716 – 791) 1,230 (1,200 – 1,280) 2,670 (2,470 – 2,940) 1,181

 2001–2002 1,310 (1,270 – 1,340) 776 (751 – 793) 1,260 (1,220 – 1,300) 2,530 (2,380 – 3,030) 1,474

 2005–2006 1,230 (1,190 – 1,260) 749 (724 – 769) 1,200 (1,160 – 1,240) 2,210 (2,080 – 2,400) 1,365

60 years and older

 1999–2000 1,510 (1,470 – 1,560) 788 (749 – 825) 1,450 (1,390 – 1,510) 3,020 (2,920 – 3,290) 1,454

 2001–2002 1,540 (1,490 – 1,590) 830 (763 – 869) 1,500 (1,440 – 1,550) 3,290 (3,030 – 3,540) 1,525

 2005–2006 1,400 (1,360 – 1,440) 783 (733 – 835) 1,390 (1,330 – 1,430) 2,600 (2,510 – 2,660) 1,387

Gender

(6 years and older)

Males

 1999–2000 1,050 (1,010 – 1,090) 580 (557 – 604) 993 (976 – 1,020) 2,280 (2,130 – 2,470) 3,426

 2001–2002 1,090 (1,060 – 1,130) 623 (607 – 646) 1,030 (986 – 1,080) 2,300 (2,160 – 2,470) 3,841

 2005–2006 1,060 (1,040 – 1,090) 610 (594 – 625) 1,030 (1,010 – 1,070) 2,010 (1,930 – 2,090) 3,547

Females

 1999–2000 1,100 (1,070 – 1,140) 605 (580 – 627) 1,030 (990 – 1,070) 2,450 (2,300 – 2,690) 3,628

 2001–2002 1,130 (1,110 – 1,150) 646 (629 – 660) 1,060 (1,040 – 1,100) 2,480 (2,280 – 2,700) 4,094

 2005–2006 1,120 (1,090 – 1,140) 653 (639 – 664) 1,080 (1,050 – 1,100) 2,170 (2,080 – 2,260) 3,707

Race/ethnicity

(6 years and older)

Mexican Americans

 1999–2000 962 (932 – 994) 572 (558 – 587) 918 (895 – 947) 1,810 (1,740 – 2,010) 2,410

 2001–2002 994 (954 – 1,040) 606 (584 – 625) 949 (917 – 979) 1,810 (1,690 – 2,080) 1,991

 2005–2006 1,010 (980 – 1,040) 623 (602 – 637) 976 (945 – 1,000) 1,790 (1,750 – 1,870) 1,844

Non-Hispanic Blacks

 1999–2000 904 (869 – 941) 566 (539 – 580) 869 (835 – 910) 1,700 (1,620 – 1,910) 1,584

 2001–2002 930 (907 – 953) 601 (573 – 617) 897 (883 – 915) 1,690 (1,540 – 1,940) 1,864

 2005–2006 933 (915 – 951) 588 (581 – 601) 903 (884 – 918) 1,660 (1,560 – 1,750) 1,891

Non-Hispanic Whites

 1999–2000 1,130 (1,100 – 1,170) 618 (600 – 634) 1,060 (1,040 – 1,100) 2,540 (2,380 – 2,720) 2,414

 2001–2002 1,160 (1,130 – 1,200) 653 (626 – 674) 1,110 (1,060 – 1,150) 2,510 (2,380 – 2,690) 3,455

 2005–2006 1,140 (1,110 – 1,160) 643 (624 – 658) 1,110 (1,080 – 1,140) 2,170 (2,090 – 2,270) 2,973
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 121121

400

500

600

700

800

5th Percentile

Total

(6+y)

99−0001−0205−06

3−5y

99−0001−0205−06

6−11y

99−0001−0205−06

12−19y 99−00 01−02

05−06

20+y

99−0001−0205−06

Males

(6+y)

99−0001−0205−06

Females

(6+y)

99−0001−0205−06

MA

(6+y)

99−0001−0205−06

NHB

(6+y)

99−0001−0205−06

NHW

(6+y)

99−0001−0205−06

600

800

1000

1200

50th Percentile

1000

1500

2000

2500

3000

95th Percentile

Figure 2.4.b. Serum vitamin E: Concentrations by survey cycle

Selected percentiles in μg/dL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2002 and 2005–2006
122 2nd 122 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.4.c. Serum vitamin E: Prevalence

Prevalence (in percent) of low serum vitamin E concentration (< 500 μg/dL) for the U.S. population 

aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Sample 

size

Prevalence 

(95% conf. interval)

Estimated total

number of persons

Total, 6 years and older 7,254 0.7 (0.5 – 0.9) 1,835,000

Age group

6–11 years 860 0.9‡ (0.4 – 2.0) 221,000‡

12–19 years 1,954 2.6 (1.6 – 4.3) 885,000

20–39 years 1,688 § §

40–59 years 1,365 0.3‡ (0.1 – 0.6) 237,000‡

60 years and older 1,387 0.4 (0.3 – 0.7) 209,000

Gender

Males 3,547 0.9 (0.6 – 1.2) 1,110,000

Females 3,707 0.5 (0.3 – 0.8) 725,000

Race/ethnicity

Mexican Americans 1,844 § §

Non-Hispanic Blacks 1,891 1.2 (0.9 – 1.7) 396,000

Non-Hispanic Whites 2,973 0.6 (0.4 – 0.8) 1,059,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 123123

Table 2.4.d. Serum vitamin E: Prevalence by survey cycle

Prevalence (in percent) of low serum vitamin E concentration (< 500 μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2002 and 2005–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 6 years and older

 1999–2000 7,054 1.0 (0.7 – 1.6) 2,558,000

 2001–2002 7,935 0.4 (0.3 – 0.6) 1,108,000

 2005–2006 7,254 0.7 (0.5 – 0.9) 1,835,000

Age group

3–5 years

 1999–2000 347 § §

 2001–2002 430 § §

6–11 years

 1999–2000 859 2.0‡ (1.0 – 4.1) 492,000‡

 2001–2002 1,014 § §

 2005–2006 860 0.9‡ (0.4 – 2.0) 221,000‡

12–19 years

 1999–2000 2,108 3.8 (2.1 – 6.8) 1,202,000

 2001–2002 2,206 1.6 (1.0 – 2.6) 509,000

 2005–2006 1,954 2.6 (1.6 – 4.3) 885,000

20–39 years

 1999–2000 1,452 0.9‡ (0.5 – 1.8) 730,000‡

 2001–2002 1,716 § §

 2005–2006 1,688 § §

40–59 years

 1999–2000 1,181 0.1‡ (0.1 – 0.2) 80,000‡

 2001–2002 1,474 § §

 2005–2006 1,365 0.3‡ (0.1 – 0.6) 237,000‡

60 years and older

 1999–2000 1,454 § §

 2001–2002 1,525 § §

 2005–2006 1,387 0.4 (0.3 – 0.7) 209,000

Gender

(6 years and older)

Males

 1999–2000 3,426 1.4 (0.8 – 2.3) 1,660,000

 2001–2002 3,841 0.6 (0.4 – 1.0) 781,000

 2005–2006 3,547 0.9 (0.6 – 1.2) 1,110,000

Females

 1999–2000 3,628 0.7 (0.4 – 1.1) 895,000

 2001–2002 4,094 0.2 (0.1 – 0.5) 325,000

 2005–2006 3,707 0.5 (0.3 – 0.8) 725,000

Race/ethnicity

(6 years and older)

Mexican Americans

 1999–2000 2,410 1.3 (0.9 – 1.8) 227,000

 2001–2002 1,991 0.7‡ (0.4 – 1.5) 156,000‡

 2005–2006 1,844 § §

Non-Hispanic Blacks

 1999–2000 1,584 1.7 (0.9 – 3.2) 520,000

 2001–2002 1,864 0.7 (0.4 – 1.1) 207,000

 2005–2006 1,891 1.2 (0.9 – 1.7) 396,000

Non-Hispanic Whites

 1999–2000 2,414 0.8 (0.5 – 1.3) 1,491,000

 2001–2002 3,455 0.3 (0.2 – 0.5) 556,000

 2005–2006 2,973 0.6 (0.4 – 0.8) 1,059,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
124

2nd 124 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.5.a.1. Serum gamma-tocopherol: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 188 (180 – 196) 53.5 (49.6 – 59.9) 70.4 (62.9 – 75.4) 196 (187 – 204) 424 (408 – 446) 489 (464 – 519) 7,217 Age group 6–11 years 182 (171 – 193) 68.1 (55.2 – 85.2) 91.5 (71.3 – 99.2) 179 (169 – 193) 353 (333 – 390) 392 (367 – 455) 858 12–19 years 179 (171 – 188) 75.5 (62.0 – 81.8) 89.0 (79.8 – 93.8) 184 (175 – 194) 324 (311 – 343) 376 (344 – 413) 1,942 20–39 years 194 (184 – 205) 65.4 (50.6 – 76.7) 81.9 (75.3 – 93.8) 200 (192 – 209) 423 (401 – 460) 489 (447 – 553) 1,675 40–59 years 201 (192 – 212) 53.0 (46.5 – 61.2) 69.0 (56.1 – 80.0) 213 (203 – 221) 452 (437 – 498) 545 (492 – 604) 1,358 60 years and older 165 (154 – 177) 45.1 (41.4 – 49.8) 52.4 (49.7 – 57.5) 176 (161 – 192) 422 (403 – 462) 486 (461 – 539) 1,384 Gender Males 192 (184 – 200) 54.9 (48.6 – 63.3) 74.5 (62.4 – 80.8) 198 (189 – 206) 434 (411 – 471) 505 (478 – 564) 3,528 Females 184 (175 – 194) 52.4 (49.4 – 58.5) 67.7 (60.1 – 73.5) 194 (183 – 203) 419 (400 – 441) 464 (444 – 497) 3,689 Race/ethnicity Mexican Americans 204 (192 – 217) 80.4 (64.2 – 86.3) 93.8 (84.0 – 102) 209 (195 – 222) 437 (390 – 503) 504 (463 – 585) 1,841 Non-Hispanic Blacks 214 (198 – 231) 70.6 (52.2 – 85.5) 92.0 (67.4 – 106) 219 (204 – 235) 429 (408 – 488) 509 (457 – 550) 1,865 Non-Hispanic Whites 182 (173 – 191) 51.2 (46.7 – 55.0) 65.1 (57.4 – 72.3) 190 (179 – 200) 423 (407 – 445) 485 (454 – 531) 2,965
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 125125

6−11 12−19 20−39 40−59 60+

0 100 200 300

Serum gamma−tocopherol (μg/dL)

Overall

6−11 12−19 20−39 40−59 60+

Mexican Americans

Females

Males

6−11 12−19 20−39 40−59 60+

0 100 200 300

Non−Hispanic Blacks

Serum gamma−tocopherol (μg/dL)

6−11 12−19 20−39 40−59 60+

Non−Hispanic Whites

6−11 12−19 20−39 40−59 60+

0 100 200 300

Serum gamma−tocopherol (μg/dL)

Females

Age (years)

6−11 12−19 20−39 40−59 60+

Males

Age (years)

Mexican

 Americans

Non−Hispanic

 Blacks

Non−Hispanic

 Whites

Figure 2.5.a. Serum gamma−tocopherol: Concentrations by age group

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006
126 2nd 126 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.5.a.2. Serum gamma-tocopherol: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 188 (180 – 196) 93.2 (86.8 – 98.0) 196 (187 – 204) 361 (347 – 385) 7,217

6–11 years 182 (171 – 193) 106 (102 – 111) 179 (169 – 193) 311 (298 – 341) 858

12–19 years 179 (171 – 188) 106 (98.1 – 114) 184 (175 – 194) 288 (276 – 304) 1,942

20–39 years 194 (184 – 205) 106 (94.7 – 114) 200 (192 – 209) 353 (330 – 393) 1,675

40–59 years 201 (192 – 212) 95.2 (84.4 – 102) 213 (203 – 221) 400 (376 – 423) 1,358

60 years and older 165 (154 – 177) 68.6 (60.9 – 73.4) 176 (161 – 192) 358 (340 – 397) 1,384

Males

Total, 6 years and older 192 (184 – 200) 98.7 (89.3 – 107) 198 (189 – 206) 359 (349 – 389) 3,528

6–11 years 177 (166 – 189) 105 (94.0 – 109) 176 (163 – 189) 304 (276 – 349) 425

12–19 years 173 (162 – 184) 103 (89.6 – 114) 177 (168 – 188) 284 (266 – 306) 974

20–39 years 202 (193 – 211) 113 (105 – 119) 203 (194 – 215) 386 (349 – 414) 732

40–59 years 207 (194 – 221) 99.0 (86.0 – 113) 215 (202 – 230) 403 (365 – 442) 669

60 years and older 171 (157 – 185) 73.7 (66.9 – 77.2) 184 (159 – 204) 354 (336 – 396) 728

Females

Total, 6 years and older 184 (175 – 194) 88.2 (80.0 – 93.8) 194 (183 – 203) 362 (338 – 388) 3,689

6–11 years 187 (174 – 201) 110 (93.6 – 122) 183 (169 – 199) 323 (299 – 346) 433

12–19 years 187 (177 – 197) 110 (101 – 119) 191 (184 – 201) 292 (274 – 313) 968

20–39 years 187 (173 – 202) 97.2 (79.9 – 110) 196 (180 – 207) 331 (312 – 383) 943

40–59 years 197 (186 – 208) 90.5 (75.5 – 99.0) 207 (195 – 223) 398 (377 – 423) 689

60 years and older 161 (148 – 175) 63.9 (53.9 – 72.6) 168 (155 – 188) 375 (328 – 405) 656

Table 2.5.a.3. Serum gamma-tocopherol: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 204 (192 – 217) 113 (106 – 117) 209 (195 – 222) 363 (343 – 403) 1,841

6–11 years 199 (178 – 221) 114 (91.6 – 122) 202 (181 – 234) 323 (303 – 388) 293

12–19 years 189 (179 – 200) 115 (106 – 124) 197 (183 – 207) 292 (279 – 316) 645

20–39 years 203 (190 – 217) 111 (107 – 116) 209 (190 – 223) 366 (333 – 429) 449

40–59 years 218 (202 – 237) 114 (91.7 – 125) 226 (213 – 240) 410 (357 – 478) 246

60 years and older 210 (196 – 225) 99.7 (90.1 – 117) 211 (194 – 224) 406 (365 – 464) 208

Males

Total, 6 years and older 206 (196 – 216) 114 (109 – 118) 210 (193 – 224) 363 (339 – 417) 881

6–11 years 196 (175 – 219) 116 (90.6 – 128) 189 (171 – 221) 329 (290 – 448) 143

12–19 years 180 (169 – 191) 109 (97.9 – 115) 187 (166 – 208) 282 (264 – 310) 313

20–39 years 207 (195 – 221) 112 (107 – 118) 216 (191 – 228) 375 (316 – 522) 198

40–59 years 226 (199 – 256) 118 (96.4 – 141) 227 (201 – 265) 376 (345 – 582) 122

60 years and older 213 (187 – 242) 100† (83.3 – 119) 205 (182 – 266) 412† (353 – 496) 105

Females

Total, 6 years and older 202 (185 – 220) 112 (96.2 – 120) 207 (194 – 221) 363 (334 – 407) 960

6–11 years 201 (171 – 237) 113 (80.8 – 128) 219 (172 – 262) 322 (303 – 373) 150

12–19 years 199 (187 – 213) 128 (113 – 137) 202 (191 – 212) 308 (286 – 375) 332

20–39 years 197 (177 – 219) 109 (93.8 – 118) 202 (180 – 219) 362 (315 – 443) 251

40–59 years 211 (187 – 237) 103 (61.5 – 121) 223 (184 – 259) 423 (351 – 515) 124

60 years and older 208 (188 – 229) 98.8† (85.1 – 120) 213 (192 – 224) 398† (315 – 506) 103

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 127127

Table 2.5.a.4. Serum gamma-tocopherol: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 214 (198 – 231) 119 (98.4 – 135) 219 (204 – 235) 383 (357 – 407) 1,865

6–11 years 198 (183 – 214) 128 (96.7 – 141) 198 (189 – 210) 317 (291 – 360) 240

12–19 years 197 (180 – 215) 126 (105 – 142) 198 (180 – 215) 308 (279 – 338) 654

20–39 years 213 (196 – 231) 114 (93.5 – 137) 216 (202 – 231) 379 (334 – 420) 359

40–59 years 221 (198 – 247) 115 (72.3 – 140) 233 (208 – 254) 404 (378 – 476) 331

60 years and older 231 (204 – 261) 109 (60.6 – 139) 255 (216 – 286) 413 (392 – 466) 281

Males

Total, 6 years and older 209 (192 – 227) 120 (102 – 136) 210 (195 – 225) 362 (335 – 402) 935

6–11 years 191 (171 – 213) 116 (69.0 – 142) 193 (182 – 205) 297 (263 – 360) 128

12–19 years 192 (176 – 210) 127 (111 – 141) 187 (170 – 208) 302 (278 – 335) 337

20–39 years 218 (197 – 241) 119 (101 – 136) 220 (195 – 240) 386 (326 – 500) 166

40–59 years 209 (182 – 241) 109 (71.2 – 141) 213 (187 – 239) 401 (311 – 526) 153

60 years and older 223 (193 – 259) 122 (53.9 – 147) 234 (202 – 276) 393 (341 – 498) 151

Females

Total, 6 years and older 218 (203 – 234) 116 (93.3 – 134) 228 (213 – 242) 396 (375 – 410) 930

6–11 years 205 (191 – 221) 131 (99.5 – 143) 204 (189 – 229) 327 (292 – 433) 112

12–19 years 202 (183 – 223) 123 (98.5 – 147) 205 (195 – 218) 314 (279 – 354) 317

20–39 years 209 (188 – 231) 110 (81.8 – 141) 213 (195 – 236) 377 (329 – 426) 193

40–59 years 231 (210 – 255) 116 (72.3 – 134) 249 (217 – 285) 404 (399 – 443) 178

60 years and older 236 (207 – 270) 103 (54.5 – 145) 261 (219 – 299) 448 (393 – 505) 130

Table 2.5.a.5. Serum gamma-tocopherol: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 182 (173 – 191) 86.4 (79.6 – 92.0) 190 (179 – 200) 356 (340 – 387) 2,965

6–11 years 175 (159 – 192) 105 (99.7 – 109) 170 (157 – 191) 304 (272 – 349) 231

12–19 years 174 (165 – 184) 102 (90.8 – 108) 179 (171 – 188) 284 (274 – 301) 499

20–39 years 191 (178 – 205) 105 (83.6 – 116) 196 (183 – 207) 349 (320 – 401) 710

40–59 years 196 (184 – 207) 91.6 (80.3 – 97.8) 207 (195 – 220) 396 (368 – 424) 680

60 years and older 158 (148 – 169) 65.9 (59.4 – 72.1) 168 (154 – 183) 353 (326 – 392) 845

Males

Total, 6 years and older 187 (178 – 197) 94.7 (81.7 – 104) 194 (184 – 204) 355 (344 – 388) 1,469

6–11 years 174 (153 – 197) 105 (82.6 – 111) 170 (150 – 192) 307 (269 – 378) 112

12–19 years 167 (155 – 180) 95.0 (76.7 – 113) 173 (163 – 181) 280 (250 – 314) 254

20–39 years 200 (190 – 210) 117 (105 – 126) 201 (188 – 212) 370 (346 – 414) 307

40–59 years 201 (185 – 218) 95.5 (80.3 – 106) 214 (195 – 230) 398 (350 – 448) 350

60 years and older 165 (151 – 180) 71.6 (62.2 – 76.5) 177 (150 – 199) 351 (331 – 380) 446

Females

Total, 6 years and older 177 (167 – 188) 79.9 (73.8 – 87.5) 186 (173 – 197) 359 (324 – 391) 1,496

6–11 years 177 (160 – 195) 104 (86.4 – 114) 171 (155 – 197) 300 (260 – 349) 119

12–19 years 182 (171 – 195) 103 (89.6 – 118) 187 (175 – 200) 289 (270 – 312) 245

20–39 years 183 (163 – 204) 92.8 (71.4 – 110) 191 (169 – 210) 323 (296 – 403) 403

40–59 years 190 (178 – 204) 83.6 (68.1 – 98.3) 203 (186 – 217) 392 (373 – 427) 330

60 years and older 153 (141 – 165) 61.1 (53.5 – 69.6) 161 (148 – 174) 357 (319 – 400) 399
128 2nd 128 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.5.b. Serum gamma-tocopherol: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2002 and 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 199 (184 – 216) 65.1 (58.2 – 71.7) 215 (197 – 230) 464 (432 – 529) 6,129

 2001–2002 199 (191 – 207) 67.1 (59.4 – 73.8) 212 (204 – 220) 461 (436 – 485) 7,879

 2005–2006 188 (180 – 196) 70.4 (62.9 – 75.4) 196 (187 – 204) 424 (408 – 446) 7,217

Age group

3–5 years

 1999–2000 170 (140 – 206) 50.0 (16.2 – 90.8) 180 (158 – 200) 363 (308 – 455) 301

 2001–2002 181 (170 – 193) 63.3 (52.2 – 82.2) 194 (178 – 205) 365 (342 – 430) 429

6–11 years

 1999–2000 202 (183 – 223) 93.3 (72.3 – 107) 213 (184 – 231) 407 (356 – 569) 725

 2001–2002 211 (203 – 219) 102 (95.4 – 109) 218 (211 – 227) 380 (361 – 414) 1,005

 2005–2006 182 (171 – 193) 91.5 (71.3 – 99.2) 179 (169 – 193) 353 (333 – 390) 858

12–19 years

 1999–2000 197 (183 – 211) 99.0 (80.4 – 112) 198 (186 – 214) 372 (363 – 389) 1,821

 2001–2002 197 (190 – 205) 99.4 (90.2 – 107) 201 (191 – 209) 368 (346 – 391) 2,188

 2005–2006 179 (171 – 188) 89.0 (79.8 – 93.8) 184 (175 – 194) 324 (311 – 343) 1,942

20–39 years

 1999–2000 205 (189 – 222) 75.6 (60.5 – 87.3) 220 (199 – 237) 438 (414 – 477) 1,299

 2001–2002 206 (197 – 216) 85.6 (73.5 – 95.3) 217 (205 – 227) 445 (425 – 474) 1,706

 2005–2006 194 (184 – 205) 81.9 (75.3 – 93.8) 200 (192 – 209) 423 (401 – 460) 1,675

40–59 years

 1999–2000 208 (185 – 232) 59.8 (51.9 – 70.0) 231 (204 – 253) 549 (507 – 631) 1,028

 2001–2002 204 (192 – 217) 60.4 (52.2 – 68.3) 221 (208 – 238) 507 (463 – 576) 1,463

 2005–2006 201 (192 – 212) 69.0 (56.1 – 80.0) 213 (203 – 221) 452 (437 – 498) 1,358

60 years and older

 1999–2000 178 (160 – 197) 47.6 (42.9 – 54.4) 196 (171 – 216) 496 (443 – 573) 1,256

 2001–2002 172 (162 – 184) 48.2 (43.8 – 52.0) 185 (170 – 201) 497 (469 – 534) 1,517

 2005–2006 165 (154 – 177) 52.4 (49.7 – 57.5) 176 (161 – 192) 422 (403 – 462) 1,384

Gender

(6 years and older)

Males

 1999–2000 199 (184 – 217) 65.3 (55.9 – 74.7) 213 (197 – 230) 462 (426 – 532) 2,974

 2001–2002 202 (193 – 211) 66.5 (56.0 – 77.1) 213 (207 – 222) 472 (445 – 499) 3,815

 2005–2006 192 (184 – 200) 74.5 (62.4 – 80.8) 198 (189 – 206) 434 (411 – 471) 3,528

Females

 1999–2000 200 (184 – 217) 64.8 (57.6 – 71.8) 217 (196 – 232) 468 (433 – 536) 3,155

 2001–2002 196 (187 – 205) 67.6 (60.6 – 74.7) 210 (200 – 220) 447 (420 – 483) 4,064

 2005–2006 184 (175 – 194) 67.7 (60.1 – 73.5) 194 (183 – 203) 419 (400 – 441) 3,689

Race/ethnicity

(6 years and older)

Mexican Americans

 1999–2000 222 (210 – 235) 104 (89.1 – 113) 225 (213 – 236) 468 (414 – 504) 1,772

 2001–2002 198 (190 – 206) 89.8 (80.5 – 92.6) 203 (190 – 214) 422 (390 – 458) 1,987

 2005–2006 204 (192 – 217) 93.8 (84.0 – 102) 209 (195 – 222) 437 (390 – 503) 1,841

Non-Hispanic Blacks

 1999–2000 213 (200 – 226) 94.5 (73.1 – 104) 217 (201 – 238) 437 (417 – 473) 1,515

 2001–2002 235 (222 – 248) 107 (83.5 – 118) 248 (233 – 261) 450 (426 – 478) 1,843

 2005–2006 214 (198 – 231) 92.0 (67.4 – 106) 219 (204 – 235) 429 (408 – 488) 1,865

Non-Hispanic Whites

 1999–2000 198 (179 – 219) 61.3 (52.8 – 70.1) 217 (192 – 234) 477 (439 – 542) 2,240

 2001–2002 193 (183 – 205) 60.4 (51.4 – 68.0) 209 (198 – 220) 472 (442 – 495) 3,426

 2005–2006 182 (173 – 191) 65.1 (57.4 – 72.3) 190 (179 – 200) 423 (407 – 445) 2,965
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 129129

0

50

100

150

5th Percentile

Total

(6+y)

99−0001−0205−06

3−5y

99−0001−0205−06

6−11y

99−0001−0205−06

12−19y 99−00 01−02

05−06

20+y

99−0001−0205−06

Males

(6+y)

99−0001−0205−06

Females

(6+y)

99−0001−0205−06

MA

(6+y)

99−0001−0205−06

NHB

(6+y)

99−0001−0205−06

NHW

(6+y)

99−0001−0205−06

150

200

250

300

50th Percentile

300

400

500

600

95th Percentile

Figure 2.5.b. Serum gamma−tocopherol: Concentrations by survey cycle

Selected percentiles in μg/dL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2002 and 2005–2006
130

2nd 130 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.6.a.1. Serum alpha-carotene: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 2.76 (2.54 – 2.99) < LOD < LOD 2.63 (2.40 – 2.84) 14.1 (12.4 – 16.5) 19.5 (17.6 – 23.7) 7,246 Age group 6–11 years 2.64 (2.32 – 3.01) < LOD < LOD 2.59 (2.31 – 2.90) 11.5 (9.30 – 15.1) 15.7 (11.6 – 34.7) 860 12–19 years 1.85 (1.69 – 2.03) < LOD < LOD 1.72 (1.53 – 1.91) 7.91 (6.65 – 10.2) 10.8 (8.96 – 15.2) 1,950 20–39 years 2.48 (2.24 – 2.74) < LOD < LOD 2.36 (2.06 – 2.69) 11.3 (10.1 – 14.7) 16.3 (12.7 – 23.6) 1,684 40–59 years 3.15 (2.85 – 3.47) < LOD < LOD 3.01 (2.72 – 3.36) 17.0 (14.5 – 21.9) 27.1 (20.3 – 35.9) 1,365 60 years and older 3.42 (3.05 – 3.83) < LOD .711 (< LOD – .811) 3.33 (2.86 – 3.86) 17.0 (14.0 – 19.8) 21.6 (19.3 – 25.9) 1,387 Gender Males 2.37 (2.20 – 2.55) < LOD < LOD 2.23 (2.06 – 2.39) 11.5 (9.92 – 13.9) 16.1 (13.2 – 20.9) 3,544 Females 3.18 (2.89 – 3.50) < LOD < LOD 3.01 (2.74 – 3.32) 16.4 (14.6 – 18.4) 23.9 (19.4 – 30.0) 3,702 Race/ethnicity Mexican Americans 2.99 (2.79 – 3.21) < LOD .824 (.749 – .889) 2.87 (2.61 – 3.21) 10.8 (10.5 – 12.5) 14.8 (13.9 – 16.6) 1,844 Non-Hispanic Blacks 1.98 (1.74 – 2.26) < LOD < LOD 1.71 (1.49 – 1.99) 11.0 (8.83 – 14.8) 15.2 (12.4 – 33.1) 1,890 Non-Hispanic Whites 2.80 (2.60 – 3.02) < LOD < LOD 2.67 (2.47 – 2.89) 14.4 (12.8 – 16.7) 20.2 (18.1 – 24.2) 2,966 < LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.
6−11 12−19 20−39 40−59 60+ 

0 2 4 6 

Serum alpha−carotene (μg/dL) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

6 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.6.a. Serum alpha−carotene: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006 Serum alpha−carotene Serum alpha−carotene (μg/dL) (μg/dL) 0 2 4 6 0 2 4 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 131131
132 2nd 132 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.6.a.2. Serum alpha-carotene: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 2.76 (2.54 – 2.99) .772 (.718 – .823) 2.63 (2.40 – 2.84) 9.48 (8.58 – 10.6) 7,246

6–11 years 2.64 (2.32 – 3.01) .865 (.766 – .966) 2.59 (2.31 – 2.90) 8.34 (6.74 – 10.9) 860

12–19 years 1.85 (1.69 – 2.03) < LOD 1.72 (1.53 – 1.91) 5.55 (4.98 – 6.67) 1,950

20–39 years 2.48 (2.24 – 2.74) .702 (< LOD – .793) 2.36 (2.06 – 2.69) 8.65 (7.55 – 9.72) 1,684

40–59 years 3.15 (2.85 – 3.47) .836 (< LOD – .963) 3.01 (2.72 – 3.36) 11.8 (10.0 – 13.3) 1,365

60 years and older 3.42 (3.05 – 3.83) 1.02 (.832 – 1.17) 3.33 (2.86 – 3.86) 10.8 (9.64 – 13.1) 1,387

Males

Total, 6 years and older 2.37 (2.20 – 2.55) < LOD 2.23 (2.06 – 2.39) 7.74 (6.73 – 9.37) 3,544

6–11 years 2.68 (2.32 – 3.10) .885 (.780 – .985) 2.59 (2.36 – 2.91) 8.27 (5.98 – 12.0) 427

12–19 years 1.60 (1.46 – 1.76) < LOD 1.40 (1.29 – 1.61) 4.51 (3.69 – 5.54) 979

20–39 years 2.10 (1.95 – 2.27) < LOD 2.00 (1.79 – 2.19) 6.91 (6.14 – 7.26) 736

40–59 years 2.66 (2.38 – 2.96) .711 (< LOD – .910) 2.47 (2.24 – 2.76) 8.79 (7.13 – 11.5) 673

60 years and older 3.01 (2.61 – 3.46) .838 (.754 – .923) 3.09 (2.55 – 3.54) 9.76 (7.73 – 12.9) 729

Females

Total, 6 years and older 3.18 (2.89 – 3.50) .895 (.807 – .983) 3.01 (2.74 – 3.32) 10.8 (9.83 – 12.3) 3,702

6–11 years 2.60 (2.26 – 2.99) .854 (.712 – .972) 2.59 (2.14 – 2.97) 8.39 (6.99 – 11.1) 433

12–19 years 2.17 (1.98 – 2.39) .709 (< LOD – .777) 2.08 (1.89 – 2.30) 6.43 (5.53 – 7.15) 971

20–39 years 2.92 (2.51 – 3.39) .859 (< LOD – .969) 2.74 (2.41 – 3.31) 9.80 (8.53 – 11.9) 948

40–59 years 3.69 (3.25 – 4.17) .992 (.764 – 1.23) 3.54 (3.07 – 3.97) 13.7 (11.7 – 16.7) 692

60 years and older 3.80 (3.33 – 4.32) 1.18 (1.01 – 1.32) 3.50 (2.94 – 4.36) 11.6 (10.2 – 15.0) 658

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

Table 2.6.a.3. Serum alpha-carotene: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 2.99 (2.79 – 3.21) 1.07 (.952 – 1.21) 2.87 (2.61 – 3.21) 7.96 (7.58 – 8.67) 1,844

6–11 years 2.53 (2.21 – 2.89) .918 (.702 – 1.14) 2.47 (2.03 – 3.00) 6.79 (5.10 – 9.28) 295

12–19 years 2.06 (1.82 – 2.33) .847 (.723 – .952) 1.89 (1.70 – 2.22) 5.19 (4.56 – 5.91) 646

20–39 years 3.09 (2.78 – 3.42) 1.22 (1.07 – 1.33) 2.88 (2.56 – 3.37) 7.74 (7.18 – 8.74) 449

40–59 years 3.72 (3.31 – 4.19) 1.44 (.784 – 1.77) 3.57 (3.24 – 4.21) 10.5 (8.26 – 14.0) 246

60 years and older 3.76 (3.31 – 4.27) 1.28 (.767 – 1.60) 3.60 (3.22 – 4.31) 9.80 (8.51 – 16.0) 208

Males

Total, 6 years and older 2.72 (2.50 – 2.95) .997 (.890 – 1.09) 2.57 (2.22 – 3.00) 7.27 (6.99 – 7.73) 883

6–11 years 2.46 (2.16 – 2.81) .904 (< LOD – 1.25) 2.49 (1.94 – 3.20) 5.58 (4.47 – 10.7) 145

12–19 years 1.92 (1.68 – 2.19) .785 (< LOD – .874) 1.75 (1.50 – 2.05) 5.16 (3.85 – 6.20) 313

20–39 years 2.71 (2.30 – 3.20) 1.08 (.902 – 1.24) 2.47 (2.01 – 3.18) 7.32 (6.06 – 8.64) 198

40–59 years 3.49 (2.95 – 4.13) 1.43 (< LOD – 1.76) 3.35 (2.71 – 4.08) 9.79 (7.00 – 15.0) 122

60 years and older 3.23 (2.73 – 3.83) .939† (< LOD – 1.50) 3.18 (2.62 – 4.23) 8.07† (6.41 – 20.8) 105

Females

Total, 6 years and older 3.33 (3.07 – 3.61) 1.20 (1.06 – 1.30) 3.26 (2.95 – 3.50) 9.08 (8.35 – 9.84) 961

6–11 years 2.60 (2.17 – 3.12) .923 (< LOD – 1.15) 2.43 (1.99 – 3.17) 7.44 (5.70 – 9.89) 150

12–19 years 2.22 (1.95 – 2.53) .937 (.732 – 1.09) 2.08 (1.81 – 2.51) 5.21 (4.55 – 6.57) 333

20–39 years 3.61 (3.16 – 4.13) 1.47 (1.16 – 1.62) 3.45 (2.84 – 4.13) 9.06 (6.93 – 13.2) 251

40–59 years 3.99 (3.38 – 4.70) 1.39 (< LOD – 1.83) 3.82 (3.37 – 4.47) 10.6 (7.74 – 33.5) 124

60 years and older 4.27 (3.70 – 4.93) 1.52† (< LOD – 2.02) 4.13 (3.36 – 5.44) 9.87† (8.65 – 22.5) 103

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 133133

Table 2.6.a.4. Serum alpha-carotene: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 1.98 (1.74 – 2.26) < LOD 1.71 (1.49 – 1.99) 6.99 (5.49 – 9.49) 1,890

6–11 years 1.97 (1.68 – 2.30) .782 (< LOD – .865) 1.73 (1.47 – 2.11) 4.97 (3.84 – 7.31) 240

12–19 years 1.33 (1.22 – 1.46) < LOD 1.17 (1.08 – 1.27) 3.23 (2.79 – 4.25) 664

20–39 years 1.76 (1.47 – 2.10) < LOD 1.54 (1.27 – 1.85) 5.49 (3.81 – 10.9) 368

40–59 years 2.60 (2.18 – 3.10) < LOD 2.40 (1.86 – 3.11) 9.63 (7.77 – 12.4) 335

60 years and older 2.28 (2.05 – 2.54) .727 (< LOD – .860) 2.09 (1.72 – 2.38) 7.35 (6.25 – 9.09) 283

Males

Total, 6 years and older 1.79 (1.56 – 2.06) < LOD 1.55 (1.30 – 1.84) 6.12 (4.82 – 7.67) 948

6–11 years 2.11 (1.80 – 2.46) .934 (.761 – 1.00) 1.90 (1.51 – 2.50) 5.11 (4.03 – 6.81) 128

12–19 years 1.28 (1.17 – 1.40) < LOD 1.18 (1.10 – 1.27) 2.65 (2.27 – 3.64) 342

20–39 years 1.51 (1.27 – 1.80) < LOD 1.26 (1.08 – 1.43) 4.23 (3.53 – 10.1) 170

40–59 years 2.34 (1.84 – 2.96) < LOD 2.10 (1.65 – 3.05) 8.08 (6.39 – 18.0) 156

60 years and older 2.04 (1.78 – 2.34) < LOD 1.75 (1.48 – 2.32) 6.11 (5.37 – 7.68) 152

Females

Total, 6 years and older 2.17 (1.91 – 2.47) < LOD 1.91 (1.61 – 2.24) 8.09 (6.12 – 10.9) 942

6–11 years 1.84 (1.47 – 2.30) < LOD 1.56 (1.31 – 2.06) 4.55 (3.38 – 34.6) 112

12–19 years 1.40 (1.24 – 1.57) < LOD 1.16 (1.01 – 1.35) 3.98 (3.08 – 4.95) 322

20–39 years 2.00 (1.63 – 2.45) < LOD 1.83 (1.46 – 2.17) 7.48 (3.92 – 14.8) 198

40–59 years 2.85 (2.40 – 3.37) .763 (< LOD – .998) 2.59 (1.91 – 3.59) 10.2 (7.96 – 12.8) 179

60 years and older 2.47 (2.08 – 2.94) .778 (< LOD – .932) 2.28 (1.69 – 3.06) 8.43 (5.57 – 13.9) 131

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

Table 2.6.a.5. Serum alpha-carotene: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 2.80 (2.60 – 3.02) .770 (< LOD – .835) 2.67 (2.47 – 2.89) 9.64 (8.79 – 10.7) 2,966

6–11 years 2.78 (2.38 – 3.24) .860 (.769 – .988) 2.77 (2.37 – 3.15) 8.80 (7.05 – 11.7) 231

12–19 years 1.95 (1.78 – 2.13) < LOD 1.85 (1.65 – 2.02) 6.10 (5.30 – 7.19) 496

20–39 years 2.39 (2.16 – 2.65) < LOD 2.31 (1.97 – 2.65) 8.10 (7.23 – 9.64) 710

40–59 years 3.12 (2.84 – 3.44) .832 (< LOD – .971) 2.95 (2.63 – 3.36) 11.9 (10.1 – 13.5) 683

60 years and older 3.44 (3.05 – 3.88) 1.05 (.832 – 1.24) 3.34 (2.82 – 3.89) 10.7 (9.59 – 12.9) 846

Males

Total, 6 years and older 2.38 (2.20 – 2.56) < LOD 2.27 (2.08 – 2.42) 7.73 (6.50 – 9.42) 1,470

6–11 years 2.80 (2.34 – 3.35) .853 (.749 – 1.02) 2.80 (2.40 – 2.99) 8.52 (5.74 – 23.7) 112

12–19 years 1.62 (1.47 – 1.78) < LOD 1.46 (1.26 – 1.72) 4.33 (3.63 – 5.81) 254

20–39 years 2.02 (1.87 – 2.18) < LOD 1.90 (1.65 – 2.22) 6.23 (5.68 – 7.29) 307

40–59 years 2.60 (2.33 – 2.90) < LOD 2.42 (2.19 – 2.68) 8.71 (6.82 – 10.2) 351

60 years and older 3.00 (2.57 – 3.49) .844 (.761 – .959) 3.09 (2.46 – 3.54) 9.36 (7.53 – 12.8) 446

Females

Total, 6 years and older 3.28 (3.00 – 3.59) .920 (.790 – 1.04) 3.10 (2.82 – 3.39) 11.2 (10.4 – 12.7) 1,496

6–11 years 2.75 (2.29 – 3.31) .864 (< LOD – 1.10) 2.76 (1.93 – 3.26) 9.09 (7.10 – 12.4) 119

12–19 years 2.39 (2.19 – 2.60) .723 (< LOD – .838) 2.22 (2.06 – 2.49) 6.93 (6.25 – 8.87) 242

20–39 years 2.83 (2.38 – 3.37) .826 (< LOD – .962) 2.69 (2.20 – 3.36) 9.45 (7.82 – 11.8) 403

40–59 years 3.73 (3.27 – 4.26) .964 (< LOD – 1.23) 3.57 (3.04 – 4.01) 14.4 (12.6 – 16.7) 332

60 years and older 3.86 (3.34 – 4.47) 1.24 (1.05 – 1.42) 3.54 (2.85 – 4.47) 12.0 (10.4 – 15.9) 400
134 2nd 134 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.6.b. Serum alpha-carotene: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 2001–2002 and 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2001–2002 2.48 (2.22 – 2.77) < LOD 2.39 (2.10 – 2.70) 12.2 (10.7 – 14.1) 7,929

 2005–2006 2.76 (2.54 – 2.99) < LOD 2.63 (2.40 – 2.84) 14.1 (12.4 – 16.5) 7,246

Age group

3–5 years

 2001–2002 2.41 (2.13 – 2.74) < LOD 2.14 (1.89 – 2.48) 12.2 (10.3 – 14.6) 430

6–11 years

 2001–2002 2.24 (2.00 – 2.51) < LOD 2.04 (1.84 – 2.28) 8.54 (6.94 – 13.3) 1,014

 2005–2006 2.64 (2.32 – 3.01) < LOD 2.59 (2.31 – 2.90) 11.5 (9.30 – 15.1) 860

12–19 years

 2001–2002 1.68 (1.52 – 1.86) < LOD 1.50 (1.37 – 1.74) 7.68 (6.61 – 9.52) 2,206

 2005–2006 1.85 (1.69 – 2.03) < LOD 1.72 (1.53 – 1.91) 7.91 (6.65 – 10.2) 1,950

20–39 years

 2001–2002 2.22 (1.93 – 2.56) < LOD 2.11 (1.82 – 2.49) 9.80 (8.96 – 12.6) 1,716

 2005–2006 2.48 (2.24 – 2.74) < LOD 2.36 (2.06 – 2.69) 11.3 (10.1 – 14.7) 1,684

40–59 years

 2001–2002 2.98 (2.60 – 3.42) < LOD 2.85 (2.47 – 3.28) 16.0 (12.8 – 20.7) 1,470

 2005–2006 3.15 (2.85 – 3.47) < LOD 3.01 (2.72 – 3.36) 17.0 (14.5 – 21.9) 1,365

60 years and older

 2001–2002 3.08 (2.74 – 3.46) < LOD 3.14 (2.71 – 3.61) 12.7 (12.0 – 13.7) 1,523

 2005–2006 3.42 (3.05 – 3.83) .711 (< LOD – .811) 3.33 (2.86 – 3.86) 17.0 (14.0 – 19.8) 1,387

Gender

(6 years and older)

Males

 2001–2002 2.22 (1.98 – 2.49) < LOD 2.07 (1.87 – 2.44) 10.3 (9.30 – 12.3) 3,835

 2005–2006 2.37 (2.20 – 2.55) < LOD 2.23 (2.06 – 2.39) 11.5 (9.92 – 13.9) 3,544

Females

 2001–2002 2.76 (2.47 – 3.07) < LOD 2.67 (2.35 – 2.97) 13.3 (11.8 – 16.2) 4,094

 2005–2006 3.18 (2.89 – 3.50) < LOD 3.01 (2.74 – 3.32) 16.4 (14.6 – 18.4) 3,702

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 2.73 (2.38 – 3.14) .726 (< LOD – .805) 2.63 (2.38 – 2.99) 10.1 (8.46 – 14.1) 1,990

 2005–2006 2.99 (2.79 – 3.21) .824 (.749 – .889) 2.87 (2.61 – 3.21) 10.8 (10.5 – 12.5) 1,844

Non-Hispanic Blacks

 2001–2002 1.77 (1.50 – 2.09) < LOD 1.58 (1.36 – 1.91) 10.1 (7.64 – 14.5) 1,864

 2005–2006 1.98 (1.74 – 2.26) < LOD 1.71 (1.49 – 1.99) 11.0 (8.83 – 14.8) 1,890

Non-Hispanic Whites

 2001–2002 2.57 (2.25 – 2.95) < LOD 2.48 (2.11 – 2.86) 12.8 (11.2 – 15.5) 3,450

 2005–2006 2.80 (2.60 – 3.02) < LOD 2.67 (2.47 – 2.89) 14.4 (12.8 – 16.7) 2,966

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 135135

0.75

0.80

0.85

0.90

5th Percentile

Total

(6+y) 01−02

05−06

3−5y 01−02

05−06

6−11y 01−02

05−06

12−19y 01−02

05−06

20+y 01−02

05−06

Males

(6+y) 01−02

05−06

Females

(6+y) 01−02

05−06

MA

(6+y) 01−02

05−06

NHB

(6+y) 01−02

05−06

NHW

(6+y) 01−02

05−06

1.0

1.5

2.0

2.5

3.0

3.5

50th Percentile

5

10

15

20

95th Percentile

Figure 2.6.b. Serum alpha−carotene: Concentrations by survey cycle

Selected percentiles in μg/dL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 2001–2002 and 2005–2006

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table.
136

2nd 136 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.7.a.1. Serum trans-beta-carotene: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 12.1 (11.5 – 12.8) 2.32 (1.98 – 2.67) 3.18 (2.92 – 3.42) 11.6 (11.1 – 12.3) 53.3 (49.1 – 59.3) 74.1 (68.1 – 83.3) 7,254 Age group 6–11 years 13.0 (12.1 – 14.0) 4.14 (2.67 – 5.05) 5.15 (4.11 – 5.61) 12.7 (11.8 – 13.6) 37.7 (29.9 – 49.2) 47.6 (39.6 – 100) 860 12–19 years 9.24 (8.76 – 9.75) 2.59 (2.05 – 2.96) 3.20 (2.87 – 3.52) 8.96 (8.30 – 9.66) 28.3 (26.3 – 30.7) 35.3 (31.3 – 41.8) 1,954 20–39 years 10.4 (9.63 – 11.3) 2.41 (1.40 – 2.81) 3.01 (2.79 – 3.23) 9.97 (9.14 – 10.9) 41.6 (36.9 – 53.3) 59.5 (48.7 – 85.1) 1,688 40–59 years 12.8 (11.9 – 13.9) 1.94 (1.36 – 2.20) 2.69 (2.15 – 3.41) 12.4 (11.6 – 13.4) 63.0 (53.5 – 73.8) 79.2 (73.3 – 97.9) 1,365 60 years and older 16.4 (15.1 – 17.7) 2.80 (2.64 – 3.20) 3.90 (3.43 – 4.17) 15.9 (14.5 – 17.8) 74.6 (66.3 – 83.4) 102 (85.9 – 143) 1,387 Gender Males 10.3 (9.89 – 10.8) 1.96 (1.40 – 2.25) 2.77 (2.28 – 3.06) 10.3 (9.62 – 10.9) 40.8 (36.8 – 46.4) 54.3 (49.4 – 66.2) 3,547 Females 14.2 (13.3 – 15.1) 2.93 (2.45 – 3.23) 3.77 (3.51 – 4.05) 13.2 (12.0 – 14.4) 64.5 (58.3 – 73.6) 84.7 (75.9 – 102) 3,707 Race/ethnicity Mexican Americans 11.5 (10.5 – 12.7) 2.67 (2.19 – 3.06) 3.49 (3.15 – 3.86) 11.3 (10.4 – 12.4) 39.2 (35.1 – 46.5) 48.6 (46.2 – 59.4) 1,844 Non-Hispanic Blacks 10.8 (9.72 – 12.0) 2.29 (2.00 – 2.54) 3.02 (2.57 – 3.36) 10.5 (9.31 – 11.4) 45.0 (38.3 – 53.7) 57.4 (51.4 – 73.5) 1,891 Non-Hispanic Whites 12.3 (11.6 – 13.1) 2.20 (1.90 – 2.65) 3.06 (2.80 – 3.41) 11.8 (11.2 – 12.6) 56.9 (50.4 – 64.9) 76.2 (72.3 – 93.3) 2,973
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 137137

6−11 12−19 20−39 40−59 60+

0 10 20 30

Serum trans−beta−carotene

(μg/dL)

Overall

6−11 12−19 20−39 40−59 60+

Mexican Americans

Females

Males

6−11 12−19 20−39 40−59 60+

0 10 20 30

Non−Hispanic Blacks

Serum trans−beta−carotene

(μg/dL)

6−11 12−19 20−39 40−59 60+

Non−Hispanic Whites

6−11 12−19 20−39 40−59 60+

0 10 20 30

Serum trans−beta−carotene

(μg/dL)

Females

Age (years)

6−11 12−19 20−39 40−59 60+

Males

Age (years)

Mexican

 Americans

Non−Hispanic

 Blacks

Non−Hispanic

 Whites

Figure 2.7.a. Serum trans−beta−carotene: Concentrations by age group

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006
138 2nd 138 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.7.a.2. Serum trans-beta-carotene: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 12.1 (11.5 – 12.8) 4.26 (4.02 – 4.53) 11.6 (11.1 – 12.3) 37.1 (34.2 – 40.7) 7,254

6–11 years 13.0 (12.1 – 14.0) 6.21 (5.49 – 6.89) 12.7 (11.8 – 13.6) 27.4 (25.1 – 31.7) 860

12–19 years 9.24 (8.76 – 9.75) 4.21 (3.86 – 4.52) 8.96 (8.30 – 9.66) 20.3 (18.9 – 22.7) 1,954

20–39 years 10.4 (9.63 – 11.3) 3.85 (3.50 – 4.19) 9.97 (9.14 – 10.9) 30.4 (26.5 – 35.8) 1,688

40–59 years 12.8 (11.9 – 13.9) 4.12 (3.59 – 4.55) 12.4 (11.6 – 13.4) 42.7 (39.1 – 47.5) 1,365

60 years and older 16.4 (15.1 – 17.7) 5.27 (4.47 – 6.08) 15.9 (14.5 – 17.8) 51.0 (45.9 – 59.1) 1,387

Males

Total, 6 years and older 10.3 (9.89 – 10.8) 3.76 (3.48 – 4.02) 10.3 (9.62 – 10.9) 28.2 (26.4 – 31.4) 3,547

6–11 years 13.7 (12.6 – 15.0) 6.93 (5.62 – 7.94) 13.1 (12.1 – 14.3) 27.4 (23.5 – 34.7) 427

12–19 years 8.46 (7.93 – 9.03) 3.82 (3.27 – 4.29) 8.26 (7.75 – 8.90) 17.8 (17.2 – 18.7) 980

20–39 years 8.89 (8.36 – 9.46) 3.36 (3.02 – 3.80) 8.51 (7.91 – 9.14) 23.9 (22.2 – 26.7) 738

40–59 years 10.5 (9.38 – 11.7) 3.43 (2.20 – 4.20) 10.8 (9.45 – 12.3) 31.8 (27.9 – 36.0) 673

60 years and older 13.3 (11.9 – 14.8) 4.47 (3.75 – 5.33) 13.0 (11.5 – 14.4) 41.5 (33.8 – 51.1) 729

Females

Total, 6 years and older 14.2 (13.3 – 15.1) 5.00 (4.60 – 5.30) 13.2 (12.0 – 14.4) 43.9 (41.2 – 48.9) 3,707

6–11 years 12.4 (11.3 – 13.5) 5.61 (4.56 – 6.75) 11.8 (10.5 – 13.6) 27.4 (24.6 – 33.5) 433

12–19 years 10.1 (9.48 – 10.9) 4.73 (4.26 – 4.95) 9.76 (8.95 – 10.7) 24.6 (20.9 – 29.1) 974

20–39 years 12.2 (10.7 – 13.9) 4.39 (3.79 – 5.08) 11.4 (10.2 – 12.9) 37.0 (28.6 – 50.2) 950

40–59 years 15.5 (14.2 – 17.0) 5.07 (4.61 – 5.33) 14.5 (12.7 – 16.2) 53.2 (44.0 – 64.4) 692

60 years and older 19.5 (17.4 – 21.8) 6.30 (5.12 – 7.04) 19.4 (16.5 – 23.1) 62.3 (50.5 – 75.2) 658

Table 2.7.a.3. Serum trans-beta-carotene: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 11.5 (10.5 – 12.7) 4.48 (4.14 – 4.81) 11.3 (10.4 – 12.4) 29.7 (25.9 – 35.0) 1,844

6–11 years 11.4 (10.6 – 12.4) 5.74 (4.57 – 6.28) 11.0 (9.92 – 12.0) 24.2 (21.0 – 31.1) 295

12–19 years 9.02 (8.39 – 9.70) 4.07 (3.59 – 4.64) 9.05 (8.35 – 10.1) 18.6 (17.3 – 22.7) 646

20–39 years 11.5 (9.84 – 13.3) 4.45 (4.01 – 4.85) 11.3 (9.45 – 13.7) 29.9 (23.5 – 37.2) 449

40–59 years 12.8 (11.1 – 14.8) 4.15 (3.63 – 5.03) 12.7 (11.1 – 14.7) 32.5 (27.7 – 47.1) 246

60 years and older 14.8 (13.2 – 16.5) 5.31 (3.02 – 7.79) 14.7 (12.7 – 15.6) 43.1 (37.9 – 47.4) 208

Males

Total, 6 years and older 10.4 (9.29 – 11.6) 4.15 (3.63 – 4.46) 10.3 (9.20 – 11.5) 25.3 (22.6 – 30.4) 883

6–11 years 12.0 (11.2 – 12.8) 6.15 (4.40 – 7.62) 11.5 (10.4 – 12.6) 23.1 (19.7 – 34.4) 145

12–19 years 8.18 (7.37 – 9.07) 3.71 (3.32 – 4.25) 8.34 (6.90 – 9.63) 17.7 (15.3 – 19.6) 313

20–39 years 10.3 (8.45 – 12.6) 4.20 (3.00 – 4.71) 9.64 (7.83 – 12.8) 26.6 (22.0 – 36.9) 198

40–59 years 10.9 (8.97 – 13.2) 3.82 (2.55 – 4.31) 11.3 (9.45 – 13.4) 26.3 (21.6 – 35.9) 122

60 years and older 12.4 (10.6 – 14.6) 4.47† (2.51 – 6.70) 12.0 (9.45 – 15.9) 35.7† (19.8 – 154) 105

Females

Total, 6 years and older 12.9 (11.9 – 14.1) 5.08 (4.51 – 5.60) 12.5 (11.6 – 13.7) 34.4 (30.2 – 39.3) 961

6–11 years 10.9 (9.63 – 12.3) 5.10 (3.98 – 5.96) 10.2 (8.54 – 11.9) 24.3 (19.4 – 32.8) 150

12–19 years 10.0 (9.35 – 10.7) 4.83 (4.12 – 5.13) 10.2 (9.47 – 10.6) 20.9 (18.0 – 28.7) 333

20–39 years 13.0 (11.1 – 15.3) 5.15 (3.69 – 6.18) 12.6 (11.2 – 15.5) 33.8 (24.6 – 45.8) 251

40–59 years 15.3 (12.6 – 18.5) 5.06 (3.42 – 6.68) 14.4 (12.2 – 18.3) 41.2 (29.2 – 108) 124

60 years and older 17.0 (14.7 – 19.7) 5.97† (3.10 – 8.19) 15.1 (14.3 – 19.4) 44.5† (39.3 – 50.9) 103

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 139139

Table 2.7.a.4. Serum trans-beta-carotene: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 10.8 (9.72 – 12.0) 4.00 (3.53 – 4.34) 10.5 (9.31 – 11.4) 31.2 (26.5 – 38.3) 1,891

6–11 years 11.9 (10.6 – 13.3) 6.30 (4.86 – 7.03) 11.6 (10.9 – 12.6) 23.0 (18.3 – 37.7) 240

12–19 years 8.46 (7.85 – 9.11) 4.09 (3.71 – 4.35) 8.13 (7.88 – 8.42) 17.9 (15.7 – 21.3) 665

20–39 years 9.32 (8.28 – 10.5) 3.85 (3.27 – 4.22) 8.49 (7.61 – 10.2) 23.4 (19.5 – 30.8) 368

40–59 years 12.1 (10.3 – 14.1) 3.46 (2.33 – 4.66) 12.3 (10.3 – 15.2) 40.9 (34.3 – 50.2) 335

60 years and older 14.7 (12.8 – 16.9) 4.60 (3.81 – 5.04) 15.3 (12.1 – 18.7) 44.8 (37.0 – 51.5) 283

Males

Total, 6 years and older 9.49 (8.62 – 10.4) 3.48 (3.00 – 3.95) 8.92 (8.05 – 9.95) 26.5 (23.0 – 32.4) 949

6–11 years 12.7 (11.1 – 14.5) 6.79 (5.53 – 7.49) 12.7 (10.7 – 14.9) 22.9 (18.7 – 55.1) 128

12–19 years 8.47 (7.78 – 9.21) 4.15 (3.18 – 4.70) 8.23 (7.85 – 8.76) 17.3 (15.8 – 19.7) 343

20–39 years 8.00 (7.09 – 9.02) 3.39 (2.51 – 3.99) 7.16 (6.35 – 7.95) 22.0 (19.3 – 26.4) 170

40–59 years 9.83 (8.14 – 11.9) 2.65 (1.98 – 3.42) 9.46 (7.15 – 13.1) 36.7 (26.2 – 66.7) 156

60 years and older 12.8 (11.3 – 14.5) 3.77 (3.46 – 4.61) 12.4 (10.7 – 15.1) 35.3 (29.1 – 52.0) 152

Females

Total, 6 years and older 12.1 (10.7 – 13.6) 4.49 (4.05 – 4.88) 11.5 (10.3 – 13.4) 35.5 (27.7 – 46.1) 942

6–11 years 11.1 (9.52 – 13.0) 5.32 (3.52 – 6.63) 11.3 (9.67 – 12.5) 22.3 (16.9 – 37.0) 112

12–19 years 8.45 (7.74 – 9.22) 4.00 (3.50 – 4.37) 8.03 (7.59 – 8.49) 18.6 (15.5 – 24.3) 322

20–39 years 10.6 (9.08 – 12.4) 4.27 (3.46 – 5.15) 10.8 (8.50 – 12.2) 25.4 (18.6 – 46.1) 198

40–59 years 14.4 (12.1 – 17.1) 4.85 (2.70 – 6.42) 14.5 (11.6 – 18.4) 44.9 (39.3 – 49.0) 179

60 years and older 16.3 (13.5 – 19.7) 4.83 (3.86 – 5.68) 17.6 (11.6 – 25.6) 46.5 (38.7 – 55.7) 131

Table 2.7.a.5. Serum trans-beta-carotene: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 12.3 (11.6 – 13.1) 4.21 (3.81 – 4.60) 11.8 (11.2 – 12.6) 39.0 (34.8 – 43.4) 2,973

6–11 years 13.6 (12.4 – 14.9) 6.31 (5.42 – 7.09) 13.2 (12.1 – 14.3) 27.8 (24.9 – 36.2) 231

12–19 years 9.58 (8.94 – 10.3) 4.36 (3.85 – 4.71) 9.14 (8.12 – 10.5) 20.9 (19.0 – 26.6) 499

20–39 years 10.1 (9.08 – 11.1) 3.53 (3.18 – 3.94) 9.78 (8.70 – 10.6) 30.5 (25.2 – 39.1) 714

40–59 years 12.9 (11.8 – 14.0) 4.10 (3.54 – 4.59) 12.4 (11.4 – 13.5) 43.4 (39.4 – 48.4) 683

60 years and older 16.3 (14.9 – 17.8) 5.29 (4.22 – 6.19) 15.9 (14.2 – 18.1) 50.9 (44.8 – 64.2) 846

Males

Total, 6 years and older 10.4 (9.87 – 11.0) 3.71 (3.35 – 4.02) 10.5 (9.56 – 11.4) 28.6 (26.0 – 33.0) 1,472

6–11 years 14.3 (12.7 – 16.1) 7.16 (4.60 – 9.03) 13.4 (12.1 – 14.7) 26.3 (23.2 – 48.8) 112

12–19 years 8.77 (8.14 – 9.46) 3.91 (2.92 – 4.60) 8.49 (7.53 – 9.58) 17.9 (16.6 – 20.4) 254

20–39 years 8.65 (8.03 – 9.32) 3.13 (2.85 – 3.48) 8.30 (7.47 – 9.44) 23.8 (20.9 – 26.9) 309

40–59 years 10.6 (9.34 – 12.0) 3.45 (2.06 – 4.26) 11.0 (9.61 – 12.4) 30.6 (26.6 – 35.9) 351

60 years and older 13.0 (11.5 – 14.7) 4.39 (3.31 – 5.39) 12.6 (11.0 – 14.3) 41.0 (32.8 – 51.7) 446

Females

Total, 6 years and older 14.5 (13.5 – 15.6) 4.95 (4.33 – 5.45) 13.4 (12.2 – 15.0) 46.4 (41.5 – 53.3) 1,501

6–11 years 12.9 (11.2 – 14.8) 5.61 (2.70 – 7.13) 12.6 (9.76 – 15.1) 27.7 (24.8 – 40.6) 119

12–19 years 10.5 (9.71 – 11.5) 4.86 (4.27 – 5.37) 9.87 (8.71 – 11.3) 26.8 (21.8 – 30.1) 245

20–39 years 11.7 (9.95 – 13.8) 4.15 (3.18 – 4.99) 10.9 (9.35 – 12.7) 36.5 (26.6 – 60.7) 405

40–59 years 15.6 (14.1 – 17.2) 5.00 (4.17 – 5.44) 14.2 (12.0 – 17.1) 57.1 (44.0 – 69.2) 332

60 years and older 19.7 (17.4 – 22.3) 6.35 (5.12 – 7.18) 19.5 (16.2 – 23.5) 64.3 (50.2 – 75.5) 400
140 2nd 140 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.7.b. Serum trans-beta-carotene: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 2001–2002 and 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2001–2002 12.2 (11.5 – 12.9) 3.21 (2.95 – 3.46) 12.0 (11.3 – 12.6) 47.7 (44.2 – 52.1) 7,929

 2005–2006 12.1 (11.5 – 12.8) 3.18 (2.92 – 3.42) 11.6 (11.1 – 12.3) 53.3 (49.1 – 59.3) 7,254

Age group

3–5 years

 2001–2002 13.6 (12.5 – 14.6) 4.60 (3.79 – 5.00) 13.6 (12.1 – 15.2) 45.1 (35.8 – 56.3) 429

6–11 years

 2001–2002 13.3 (12.7 – 13.9) 5.44 (5.00 – 5.96) 13.2 (12.5 – 13.9) 32.9 (30.4 – 38.8) 1,012

 2005–2006 13.0 (12.1 – 14.0) 5.15 (4.11 – 5.61) 12.7 (11.8 – 13.6) 37.7 (29.9 – 49.2) 860

12–19 years

 2001–2002 9.69 (9.20 – 10.2) 3.34 (2.97 – 3.59) 9.63 (8.97 – 10.4) 28.2 (25.4 – 32.5) 2,206

 2005–2006 9.24 (8.76 – 9.75) 3.20 (2.87 – 3.52) 8.96 (8.30 – 9.66) 28.3 (26.3 – 30.7) 1,954

20–39 years

 2001–2002 10.3 (9.38 – 11.2) 2.90 (2.13 – 3.20) 9.81 (9.10 – 10.8) 39.8 (35.2 – 42.6) 1,716

 2005–2006 10.4 (9.63 – 11.3) 3.01 (2.79 – 3.23) 9.97 (9.14 – 10.9) 41.6 (36.9 – 53.3) 1,688

40–59 years

 2001–2002 13.3 (12.1 – 14.7) 3.30 (2.74 – 3.65) 13.0 (12.0 – 14.2) 60.0 (49.9 – 79.7) 1,471

 2005–2006 12.8 (11.9 – 13.9) 2.69 (2.15 – 3.41) 12.4 (11.6 – 13.4) 63.0 (53.5 – 73.8) 1,365

60 years and older

 2001–2002 16.5 (14.9 – 18.3) 3.51 (2.88 – 4.13) 17.5 (15.3 – 19.6) 61.4 (56.0 – 66.1) 1,524

 2005–2006 16.4 (15.1 – 17.7) 3.90 (3.43 – 4.17) 15.9 (14.5 – 17.8) 74.6 (66.3 – 83.4) 1,387

Gender

(6 years and older)

Males

 2001–2002 10.9 (10.2 – 11.6) 3.01 (2.68 – 3.25) 11.0 (10.3 – 11.6) 42.1 (37.5 – 45.5) 3,837

 2005–2006 10.3 (9.89 – 10.8) 2.77 (2.28 – 3.06) 10.3 (9.62 – 10.9) 40.8 (36.8 – 46.4) 3,547

Females

 2001–2002 13.6 (12.7 – 14.6) 3.57 (3.37 – 3.83) 13.1 (12.2 – 14.2) 54.1 (47.6 – 62.0) 4,092

 2005–2006 14.2 (13.3 – 15.1) 3.77 (3.51 – 4.05) 13.2 (12.0 – 14.4) 64.5 (58.3 – 73.6) 3,707

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 12.5 (11.6 – 13.4) 3.56 (3.12 – 3.83) 12.9 (11.6 – 13.9) 38.5 (34.5 – 47.5) 1,990

 2005–2006 11.5 (10.5 – 12.7) 3.49 (3.15 – 3.86) 11.3 (10.4 – 12.4) 39.2 (35.1 – 46.5) 1,844

Non-Hispanic Blacks

 2001–2002 10.8 (9.90 – 11.8) 2.83 (2.42 – 3.22) 10.7 (9.93 – 11.6) 40.3 (35.4 – 45.6) 1,864

 2005–2006 10.8 (9.72 – 12.0) 3.02 (2.57 – 3.36) 10.5 (9.31 – 11.4) 45.0 (38.3 – 53.7) 1,891

Non-Hispanic Whites

 2001–2002 12.5 (11.5 – 13.6) 3.35 (3.06 – 3.61) 12.1 (11.3 – 13.0) 50.8 (45.8 – 56.9) 3,450

 2005–2006 12.3 (11.6 – 13.1) 3.06 (2.80 – 3.41) 11.8 (11.2 – 12.6) 56.9 (50.4 – 64.9) 2,973
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 141141

2

3

4

5

6

5th Percentile

Total

(6+y) 01−02

05−06

3−5y 01−02

05−06

6−11y 01−02

05−06

12−19y 01−02

05−06

20+y 01−02

05−06

Males

(6+y) 01−02

05−06

Females

(6+y) 01−02

05−06

MA

(6+y) 01−02

05−06

NHB

(6+y) 01−02

05−06

NHW

(6+y) 01−02

05−06

8

10

12

14

16

50th Percentile

20

40

60

80

95th Percentile

Figure 2.7.b. Serum trans−beta−carotene: Concentrations by survey cycle

Selected percentiles in μg/dL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 2001–2002 and 2005–2006
142

2nd 142 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.8.a.1. Serum cis-beta-carotene: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older * < LOD < LOD < LOD 3.20 (2.87 – 3.64) 4.48 (3.93 – 5.11) 6,616 Age group 6–11 years * < LOD < LOD < LOD 1.95 (1.63 – 2.68) 2.67 (2.16 – 4.22) 779 12–19 years * < LOD < LOD < LOD 1.47 (1.33 – 1.81) 1.87 (1.58 – 2.39) 1,785 20–39 years * < LOD < LOD < LOD 2.51 (2.08 – 3.19) 3.74 (2.88 – 5.09) 1,528 40–59 years * < LOD < LOD .730 (< LOD – .783) 3.73 (3.21 – 4.44) 4.84 (4.34 – 5.50) 1,254 60 years and older 1.08 (.985 – 1.17) < LOD < LOD .903 (.811 – .992) 4.59 (3.93 – 5.32) 6.53 (5.17 – 8.65) 1,270 Gender Males * < LOD < LOD < LOD 2.26 (1.99 – 2.60) 3.09 (2.67 – 3.91) 3,204 Females * < LOD < LOD .759 (.708 – .816) 3.88 (3.60 – 4.48) 5.27 (4.71 – 6.32) 3,412 Race/ethnicity Mexican Americans * < LOD < LOD < LOD 2.26 (1.97 – 2.59) 2.80 (2.48 – 3.46) 1,707 Non-Hispanic Blacks * < LOD < LOD < LOD 2.81 (2.37 – 3.38) 3.51 (3.17 – 4.61) 1,673 Non-Hispanic Whites * < LOD < LOD < LOD 3.44 (3.06 – 3.82) 4.71 (4.11 – 5.20) 2,725 < LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. * Not calculated. Proportion of results below limit of detection was too high to provide a valid result.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 143143

No cis-beta-carotene figure for concentrations by age group is presented because the geometric

means were not calculated due to the proportion of results below the limit of detection being

too high for valid results (see Table 2.8.a.1).
144 2nd 144 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.8.a.2. Serum cis-beta-carotene: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older * < LOD < LOD 2.10 (1.92 – 2.39) 6,616

6–11 years * < LOD < LOD 1.47 (1.28 – 1.78) 779

12–19 years * < LOD < LOD 1.12 (.995 – 1.26) 1,785

20–39 years * < LOD < LOD 1.78 (1.55 – 2.03) 1,528

40–59 years * < LOD .730 (< LOD – .783) 2.49 (2.18 – 2.86) 1,254

60 years and older 1.08 (.985 – 1.17) < LOD .903 (.811 – .992) 3.09 (2.62 – 3.64) 1,270

Males

Total, 6 years and older * < LOD < LOD 1.59 (1.43 – 1.86) 3,204

6–11 years * < LOD .704 (< LOD – .757) 1.52 (1.26 – 2.33) 386

12–19 years * < LOD < LOD .935 (.878 – 1.02) 886

20–39 years * < LOD < LOD 1.37 (1.23 – 1.59) 652

40–59 years * < LOD < LOD 1.75 (1.50 – 2.05) 616

60 years and older * < LOD .726 (< LOD – .817) 2.37 (1.91 – 2.99) 664

Females

Total, 6 years and older * < LOD .759 (.708 – .816) 2.70 (2.35 – 3.10) 3,412

6–11 years * < LOD < LOD 1.44 (1.21 – 1.74) 393

12–19 years * < LOD < LOD 1.35 (1.13 – 1.59) 899

20–39 years * < LOD < LOD 2.15 (1.77 – 3.04) 876

40–59 years 1.04 (.954 – 1.13) < LOD .827 (.745 – .963) 3.30 (2.72 – 3.78) 638

60 years and older 1.26 (1.11 – 1.41) < LOD 1.15 (.904 – 1.36) 3.69 (3.23 – 4.71) 606

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.

Table 2.8.a.3. Serum cis-beta-carotene: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older * < LOD < LOD 1.70 (1.52 – 1.91) 1,707

6–11 years * < LOD < LOD 1.34 (1.09 – 1.67) 269

12–19 years * < LOD < LOD .975 (.899 – 1.15) 609

20–39 years * < LOD < LOD 1.73 (1.42 – 2.02) 402

40–59 years .880 (.780 – .992) < LOD .751 (< LOD – .864) 1.97 (1.65 – 2.75) 228

60 years and older .964 (.878 – 1.06) < LOD .854 (.778 – .919) 2.48 (2.05 – 3.55) 199

Males

Total, 6 years and older * < LOD < LOD 1.47 (1.21 – 1.71) 814

6–11 years * < LOD < LOD 1.34 (1.06 – 1.98) 131

12–19 years * < LOD < LOD .900 (.833 – 1.09) 299

20–39 years * < LOD < LOD 1.58 (1.16 – 2.07) 171

40–59 years * < LOD < LOD 1.57 (1.29 – 2.19) 114

60 years and older * < LOD† .718 (< LOD – .904) 1.61† (1.08 – 10.8) 99

Females

Total, 6 years and older * < LOD .720 (< LOD – .789) 1.95 (1.76 – 2.24) 893

6–11 years * < LOD < LOD 1.35 (1.06 – 1.72) 138

12–19 years * < LOD < LOD 1.10 (.944 – 1.46) 310

20–39 years * < LOD .774 (< LOD – .960) 1.88 (1.57 – 2.36) 231

40–59 years 1.00 (.839 – 1.19) < LOD .870 (.703 – 1.06) 2.23 (1.71 – 6.40) 114

60 years and older 1.09 (.959 – 1.24) < LOD† .923 (.853 – 1.06) 2.85† (2.37 – 4.06) 100

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 145145

Table 2.8.a.4. Serum cis-beta-carotene: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older * < LOD < LOD 1.87 (1.59 – 2.49) 1,673

6–11 years * < LOD < LOD 1.33 (1.12 – 2.11) 208

12–19 years * < LOD < LOD 1.05 (.916 – 1.20) 580

20–39 years * < LOD < LOD 1.41 (1.24 – 1.84) 327

40–59 years * < LOD .778 (< LOD – .937) 2.54 (2.16 – 3.11) 298

60 years and older 1.04 (.906 – 1.19) < LOD .965 (.778 – 1.09) 2.80 (2.23 – 3.45) 260

Males

Total, 6 years and older * < LOD < LOD 1.61 (1.33 – 1.94) 827

6–11 years .807 (.695 – .937) < LOD .738 (< LOD – .876) 1.45 (1.13 – 6.80) 112

12–19 years * < LOD < LOD .997 (.882 – 1.17) 290

20–39 years * < LOD < LOD 1.27 (.962 – 1.84) 149

40–59 years * < LOD < LOD 2.28 (1.51 – 3.29) 136

60 years and older * < LOD .784 (< LOD – .927) 1.95 (1.64 – 3.14) 140

Females

Total, 6 years and older * < LOD .717 (< LOD – .832) 2.20 (1.83 – 2.77) 846

6–11 years * < LOD† < LOD 1.19† (1.03 – 1.99) 96

12–19 years * < LOD < LOD 1.08 (.914 – 1.42) 290

20–39 years * < LOD < LOD 1.62 (1.25 – 2.76) 178

40–59 years 1.01 (.886 – 1.16) < LOD .877 (.765 – 1.03) 2.82 (2.25 – 3.43) 162

60 years and older 1.17 (.947 – 1.44) < LOD 1.10 (.720 – 1.58) 3.16 (2.59 – 3.84) 120

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.

† Estimate is subject to greater uncertainty due to small cell size.

Table 2.8.a.5. Serum cis-beta-carotene: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older * < LOD < LOD 2.17 (1.92 – 2.55) 2,725

6–11 years * < LOD < LOD 1.46 (1.21 – 2.42) 212

12–19 years * < LOD < LOD 1.16 (.979 – 1.39) 462

20–39 years * < LOD < LOD 1.74 (1.44 – 2.15) 653

40–59 years * < LOD .720 (< LOD – .779) 2.50 (2.11 – 3.14) 634

60 years and older 1.07 (.967 – 1.18) < LOD .892 (.783 – 1.00) 3.09 (2.57 – 3.70) 764

Males

Total, 6 years and older * < LOD < LOD 1.59 (1.42 – 1.92) 1,336

6–11 years * < LOD† < LOD 1.49† (1.16 – 5.17) 102

12–19 years * < LOD < LOD .926 (.842 – 1.19) 231

20–39 years * < LOD < LOD 1.35 (1.18 – 1.59) 278

40–59 years * < LOD < LOD 1.69 (1.46 – 1.99) 324

60 years and older * < LOD < LOD 2.39 (1.82 – 3.14) 401

Females

Total, 6 years and older * < LOD .761 (.704 – .828) 2.79 (2.34 – 3.48) 1,389

6–11 years * < LOD† < LOD 1.43† (1.19 – 1.98) 110

12–19 years * < LOD < LOD 1.39 (1.12 – 1.85) 231

20–39 years * < LOD < LOD 2.14 (1.62 – 3.70) 375

40–59 years 1.03 (.941 – 1.13) < LOD .795 (.718 – .966) 3.55 (2.73 – 3.96) 310

60 years and older 1.26 (1.10 – 1.45) < LOD 1.16 (.875 – 1.38) 3.70 (3.16 – 4.80) 363

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.

† Estimate is subject to greater uncertainty due to small cell size.
146 2nd 146 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.8.b. Serum cis-beta-carotene: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 2001–2002 and 2005–2006.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2001–2002 * < LOD < LOD 2.64 (2.41 – 2.87) 7,929

 2005–2006 * < LOD < LOD 3.20 (2.87 – 3.64) 6,616

Age group

3–5 years

 2001–2002 * < LOD < LOD 2.07 (1.88 – 2.62) 430

6–11 years

 2001–2002 * < LOD < LOD 1.64 (1.50 – 1.84) 1,014

 2005–2006 * < LOD < LOD 1.95 (1.63 – 2.68) 779

12–19 years

 2001–2002 * < LOD < LOD 1.39 (1.30 – 1.55) 2,206

 2005–2006 * < LOD < LOD 1.47 (1.33 – 1.81) 1,785

20–39 years

 2001–2002 * < LOD < LOD 2.05 (1.82 – 2.46) 1,716

 2005–2006 * < LOD < LOD 2.51 (2.08 – 3.19) 1,528

40–59 years

 2001–2002 * < LOD < LOD 3.30 (2.77 – 4.39) 1,470

 2005–2006 * < LOD .730 (< LOD – .783) 3.73 (3.21 – 4.44) 1,254

60 years and older

 2001–2002 1.02 (.943 – 1.11) < LOD .899 (.803 – 1.02) 3.50 (3.11 – 3.94) 1,523

 2005–2006 1.08 (.985 – 1.17) < LOD .903 (.811 – .992) 4.59 (3.93 – 5.32) 1,270

Gender

(6 years and older)

Males

 2001–2002 * < LOD < LOD 2.13 (1.94 – 2.41) 3,835

 2005–2006 * < LOD < LOD 2.26 (1.99 – 2.60) 3,204

Females

 2001–2002 * < LOD < LOD 3.08 (2.73 – 3.70) 4,094

 2005–2006 * < LOD .759 (.708 – .816) 3.88 (3.60 – 4.48) 3,412

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 * < LOD < LOD 2.06 (1.85 – 2.42) 1,990

 2005–2006 * < LOD < LOD 2.26 (1.97 – 2.59) 1,707

Non-Hispanic Blacks

 2001–2002 * < LOD < LOD 2.29 (1.96 – 2.69) 1,864

 2005–2006 * < LOD < LOD 2.81 (2.37 – 3.38) 1,673

Non-Hispanic Whites

 2001–2002 * < LOD < LOD 2.79 (2.48 – 3.28) 3,450

 2005–2006 * < LOD < LOD 3.44 (3.06 – 3.82) 2,725

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

* Not calculated. Proportion of results below limit of detection was too high to provide a valid result.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 147147

0.70

0.75

0.80

0.85

5th Percentile

Total

(6+y) 01−02

05−06

3−5y 01−02

05−06

6−11y 01−02

05−06

12−19y 01−02

05−06

20+y 01−02

05−06

Males 01−02

05−06

Females 01−02

05−06

MA01−02

05−06

NHB01−02

05−06

NHW01−02

05−06

0.70

0.75

0.80

0.85

50th Percentile

1

2

3

4

5

95th Percentile

Figure 2.8.b. Serum cis−beta−carotene: Concentrations by survey cycle

Selected percentiles in μg/dL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 2001–2002 and 2005–2006

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table.
148

2nd 148 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.9.a.1. Serum beta-cryptoxanthin: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 7.70 (7.34 – 8.08) 1.90 (1.63 – 2.06) 2.46 (2.26 – 2.63) 7.62 (7.24 – 7.99) 24.1 (22.5 – 26.4) 30.5 (28.7 – 33.2) 7,195 Age group 6–11 years 9.47 (8.88 – 10.1) 3.41 (2.68 – 3.69) 3.90 (3.32 – 4.23) 9.14 (8.52 – 9.66) 24.9 (23.0 – 28.7) 30.4 (27.1 – 42.3) 855 12–19 years 7.82 (7.42 – 8.23) 2.56 (2.13 – 2.97) 3.20 (2.91 – 3.50) 7.49 (7.01 – 7.99) 20.3 (18.8 – 23.4) 25.5 (23.6 – 27.2) 1,924 20–39 years 7.95 (7.52 – 8.40) 2.33 (1.84 – 2.53) 2.78 (2.50 – 2.97) 7.81 (7.31 – 8.18) 24.5 (21.7 – 28.8) 31.7 (28.8 – 38.0) 1,679 40–59 years 7.24 (6.60 – 7.94) 1.48 (1.14 – 1.92) 2.16 (1.80 – 2.40) 7.03 (6.50 – 7.82) 24.8 (21.5 – 29.2) 30.3 (27.7 – 41.1) 1,357 60 years and older 7.39 (6.86 – 7.97) 1.52 (1.38 – 1.62) 1.98 (1.62 – 2.25) 7.48 (7.03 – 8.13) 24.2 (22.7 – 27.6) 31.9 (27.8 – 35.2) 1,380 Gender Males 7.51 (7.10 – 7.94) 1.86 (1.42 – 2.14) 2.41 (2.10 – 2.70) 7.49 (7.12 – 7.88) 22.8 (21.5 – 25.0) 28.4 (26.4 – 30.9) 3,514 Females 7.89 (7.53 – 8.27) 1.93 (1.68 – 2.10) 2.54 (2.24 – 2.69) 7.74 (7.28 – 8.14) 25.5 (23.4 – 28.1) 32.5 (30.0 – 37.1) 3,681 Race/ethnicity Mexican Americans 13.0 (11.8 – 14.3) 3.45 (3.15 – 3.89) 4.42 (3.87 – 4.86) 12.9 (11.9 – 14.2) 36.2 (32.4 – 45.4) 46.2 (40.7 – 63.0) 1,842 Non-Hispanic Blacks 8.34 (7.88 – 8.84) 2.32 (2.02 – 2.51) 2.89 (2.59 – 3.11) 8.23 (7.80 – 8.81) 23.6 (20.8 – 27.8) 29.8 (26.9 – 35.6) 1,848 Non-Hispanic Whites 6.94 (6.59 – 7.32) 1.66 (1.47 – 1.92) 2.26 (2.07 – 2.44) 6.96 (6.62 – 7.38) 20.5 (19.7 – 21.9) 25.5 (23.3 – 28.2) 2,960
6−11 12−19 20−39 40−59 60+ 

0 5 10 15 20

Serum beta−cryptoxanthin (μg/dL) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

20 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.9.a. Serum beta−cryptoxanthin: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006 Serum beta−cryptoxanthin Serum beta−cryptoxanthin (μg/dL) (μg/dL) 0 5 10 15 20 0 5 10 15 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 149149
150 2nd 150 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.9.a.2. Serum beta-cryptoxanthin: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 7.70 (7.34 – 8.08) 3.17 (2.95 – 3.36) 7.62 (7.24 – 7.99) 18.5 (17.5 – 19.7) 7,195

6–11 years 9.47 (8.88 – 10.1) 4.47 (3.95 – 5.23) 9.14 (8.52 – 9.66) 19.5 (17.8 – 21.7) 855

12–19 years 7.82 (7.42 – 8.23) 3.86 (3.64 – 4.01) 7.49 (7.01 – 7.99) 16.5 (15.2 – 17.8) 1,924

20–39 years 7.95 (7.52 – 8.40) 3.42 (3.06 – 3.76) 7.81 (7.31 – 8.18) 18.2 (16.7 – 20.0) 1,679

40–59 years 7.24 (6.60 – 7.94) 2.76 (2.48 – 3.06) 7.03 (6.50 – 7.82) 19.3 (17.2 – 21.2) 1,357

60 years and older 7.39 (6.86 – 7.97) 2.82 (2.40 – 3.01) 7.48 (7.03 – 8.13) 19.0 (17.4 – 20.7) 1,380

Males

Total, 6 years and older 7.51 (7.10 – 7.94) 3.13 (2.87 – 3.38) 7.49 (7.12 – 7.88) 18.0 (17.1 – 19.3) 3,514

6–11 years 9.70 (8.87 – 10.6) 4.86 (3.91 – 5.70) 9.33 (8.48 – 10.2) 19.2 (17.3 – 21.7) 426

12–19 years 7.89 (7.36 – 8.46) 3.95 (3.55 – 4.37) 7.65 (7.02 – 8.42) 16.9 (15.0 – 18.6) 961

20–39 years 7.86 (7.38 – 8.38) 3.49 (3.11 – 3.88) 7.74 (7.16 – 8.22) 17.9 (16.0 – 19.5) 735

40–59 years 6.84 (6.09 – 7.69) 2.58 (2.16 – 2.91) 6.74 (6.12 – 7.68) 18.8 (16.7 – 21.9) 668

60 years and older 7.01 (6.37 – 7.70) 2.87 (2.36 – 3.05) 7.16 (6.44 – 7.89) 17.6 (16.7 – 20.5) 724

Females

Total, 6 years and older 7.89 (7.53 – 8.27) 3.21 (2.99 – 3.40) 7.74 (7.28 – 8.14) 19.1 (17.9 – 20.2) 3,681

6–11 years 9.23 (8.67 – 9.83) 4.21 (3.49 – 4.98) 8.82 (8.30 – 9.60) 19.7 (17.8 – 23.4) 429

12–19 years 7.73 (7.26 – 8.23) 3.77 (3.48 – 3.96) 7.32 (6.78 – 8.01) 16.3 (14.9 – 17.8) 963

20–39 years 8.04 (7.52 – 8.59) 3.32 (2.93 – 3.81) 7.87 (7.27 – 8.51) 19.3 (17.0 – 23.4) 944

40–59 years 7.63 (6.94 – 8.39) 3.08 (2.66 – 3.33) 7.35 (6.62 – 8.25) 19.7 (17.2 – 20.9) 689

60 years and older 7.73 (7.04 – 8.48) 2.79 (2.34 – 3.03) 7.73 (7.23 – 8.79) 20.0 (18.1 – 22.9) 656

Table 2.9.a.3. Serum beta-cryptoxanthin: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 13.0 (11.8 – 14.3) 5.53 (5.21 – 5.91) 12.9 (11.9 – 14.2) 29.7 (25.9 – 34.0) 1,842

6–11 years 12.4 (11.4 – 13.5) 6.01 (4.82 – 6.78) 12.3 (11.0 – 14.0) 24.8 (23.0 – 27.8) 295

12–19 years 11.1 (10.3 – 12.1) 5.77 (5.11 – 6.34) 11.0 (10.2 – 12.1) 22.8 (19.2 – 26.1) 646

20–39 years 13.6 (11.7 – 16.0) 5.47 (4.92 – 6.41) 13.5 (11.7 – 15.7) 31.9 (26.5 – 45.3) 448

40–59 years 13.3 (11.7 – 15.2) 5.34 (4.80 – 5.81) 13.6 (11.9 – 15.8) 29.8 (25.8 – 35.3) 245

60 years and older 13.3 (11.4 – 15.6) 5.60 (2.79 – 7.53) 13.4 (11.3 – 15.8) 29.7 (24.7 – 42.9) 208

Males

Total, 6 years and older 12.6 (11.2 – 14.1) 5.38 (4.94 – 5.92) 12.7 (11.4 – 14.4) 27.9 (24.5 – 32.7) 881

6–11 years 12.5 (11.3 – 13.8) 6.02 (3.82 – 6.86) 12.5 (11.2 – 14.4) 24.3 (22.2 – 32.0) 145

12–19 years 10.7 (9.74 – 11.9) 6.00 (5.02 – 6.51) 10.5 (9.42 – 11.6) 21.7 (18.5 – 26.0) 313

20–39 years 13.5 (11.1 – 16.4) 5.38 (4.43 – 6.71) 13.8 (11.6 – 16.0) 29.6 (22.6 – 45.6) 197

40–59 years 12.6 (10.5 – 15.0) 5.06 (3.45 – 5.65) 13.0 (10.4 – 15.5) 30.6 (25.0 – 45.0) 121

60 years and older 12.0 (9.50 – 15.1) 4.24† (1.40 – 7.66) 11.4 (9.88 – 15.0) 26.9† (21.1 – 37.5) 105

Females

Total, 6 years and older 13.4 (12.2 – 14.6) 5.64 (5.31 – 6.10) 13.1 (12.2 – 14.2) 30.8 (26.8 – 39.3) 961

6–11 years 12.3 (11.3 – 13.5) 5.87 (4.89 – 6.83) 11.8 (10.9 – 13.3) 26.0 (21.9 – 28.8) 150

12–19 years 11.6 (10.6 – 12.7) 5.49 (4.35 – 6.31) 12.1 (10.9 – 13.0) 23.4 (19.9 – 30.4) 333

20–39 years 13.8 (11.7 – 16.2) 5.49 (4.69 – 6.54) 13.0 (11.0 – 16.0) 34.7 (29.7 – 47.2) 251

40–59 years 14.2 (12.2 – 16.4) 5.67 (3.59 – 7.24) 13.7 (12.5 – 16.3) 29.5 (24.9 – 36.5) 124

60 years and older 14.5 (11.8 – 18.0) 5.79† (3.11 – 7.70) 15.4 (12.2 – 17.4) 30.1† (25.5 – 59.9) 103

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 151151

Table 2.9.a.4. Serum beta-cryptoxanthin: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 8.34 (7.88 – 8.84) 3.72 (3.51 – 4.02) 8.23 (7.80 – 8.81) 18.1 (17.2 – 19.3) 1,848

6–11 years 11.9 (11.1 – 12.8) 6.05 (5.13 – 6.76) 11.7 (10.6 – 13.2) 22.8 (19.7 – 25.0) 237

12–19 years 8.69 (7.99 – 9.46) 4.54 (4.16 – 4.92) 8.47 (7.65 – 9.40) 17.4 (15.7 – 19.0) 637

20–39 years 8.26 (7.76 – 8.78) 3.97 (3.62 – 4.26) 7.95 (7.47 – 8.71) 16.3 (15.0 – 18.9) 363

40–59 years 7.89 (6.95 – 8.97) 2.90 (2.54 – 3.55) 7.98 (6.88 – 9.10) 18.8 (17.2 – 22.3) 332

60 years and older 7.38 (6.55 – 8.31) 3.16 (2.61 – 3.71) 7.31 (6.35 – 8.23) 16.8 (15.5 – 21.8) 279

Males

Total, 6 years and older 8.23 (7.64 – 8.87) 3.58 (3.20 – 3.89) 8.03 (7.38 – 8.90) 19.0 (17.7 – 20.9) 922

6–11 years 12.5 (11.2 – 14.0) 6.69 (4.92 – 7.69) 12.6 (10.6 – 14.7) 23.9 (21.5 – 25.6) 127

12–19 years 8.80 (8.01 – 9.67) 4.43 (3.92 – 4.96) 8.50 (7.75 – 9.40) 18.2 (15.8 – 20.7) 325

20–39 years 8.26 (7.73 – 8.83) 4.00 (3.65 – 4.31) 7.41 (7.04 – 7.98) 18.2 (15.3 – 21.6) 168

40–59 years 7.49 (6.22 – 9.03) 2.63 (2.42 – 2.81) 7.64 (6.42 – 9.09) 19.0 (17.1 – 24.6) 153

60 years and older 6.73 (6.08 – 7.45) 2.92 (2.43 – 3.29) 6.06 (5.09 – 7.20) 17.0 (15.6 – 17.8) 149

Females

Total, 6 years and older 8.44 (8.04 – 8.86) 3.87 (3.56 – 4.40) 8.39 (8.01 – 8.86) 17.3 (16.4 – 18.5) 926

6–11 years 11.2 (9.74 – 13.0) 5.33† (4.18 – 6.55) 10.8 (9.90 – 12.2) 19.6† (17.8 – 30.0) 110

12–19 years 8.59 (7.79 – 9.46) 4.66 (4.22 – 5.04) 8.46 (7.40 – 9.63) 16.6 (14.9 – 18.0) 312

20–39 years 8.25 (7.69 – 8.86) 3.73 (3.50 – 4.18) 8.14 (7.80 – 8.94) 15.6 (13.7 – 20.1) 195

40–59 years 8.24 (7.42 – 9.14) 3.64 (2.54 – 4.52) 8.22 (6.90 – 9.23) 18.5 (16.3 – 21.5) 179

60 years and older 7.89 (6.67 – 9.33) 3.67 (2.29 – 4.00) 7.96 (6.64 – 9.20) 16.5 (14.7 – 26.2) 130

† Estimate is subject to greater uncertainty due to small cell size.

Table 2.9.a.5. Serum beta-cryptoxanthin: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 6.94 (6.59 – 7.32) 2.93 (2.72 – 3.14) 6.96 (6.62 – 7.38) 16.3 (15.3 – 17.4) 2,960

6–11 years 8.29 (7.73 – 8.89) 4.21 (3.43 – 4.88) 8.12 (7.60 – 8.69) 15.7 (14.5 – 17.9) 230

12–19 years 7.12 (6.60 – 7.68) 3.72 (3.31 – 3.93) 6.82 (6.07 – 7.64) 14.2 (13.1 – 16.1) 497

20–39 years 6.90 (6.60 – 7.21) 3.01 (2.73 – 3.40) 6.93 (6.69 – 7.24) 15.1 (13.3 – 16.5) 711

40–59 years 6.63 (5.99 – 7.33) 2.63 (2.35 – 2.88) 6.61 (6.11 – 7.28) 17.2 (14.6 – 20.0) 679

60 years and older 7.05 (6.51 – 7.64) 2.75 (2.28 – 2.96) 7.26 (6.66 – 7.79) 17.7 (16.8 – 19.6) 843

Males

Total, 6 years and older 6.83 (6.42 – 7.28) 2.92 (2.50 – 3.23) 6.90 (6.58 – 7.29) 15.9 (14.6 – 17.5) 1,468

6–11 years 8.45 (7.44 – 9.60) 4.43 (3.50 – 5.65) 7.99 (7.29 – 9.15) 15.9 (14.0 – 21.0) 112

12–19 years 7.38 (6.60 – 8.26) 3.87 (3.20 – 4.40) 7.10 (6.14 – 8.39) 14.5 (12.6 – 17.5) 253

20–39 years 6.94 (6.51 – 7.40) 3.15 (2.80 – 3.53) 7.06 (6.75 – 7.53) 14.0 (12.1 – 16.7) 309

40–59 years 6.39 (5.62 – 7.26) 2.42 (1.99 – 2.82) 6.31 (5.75 – 6.96) 17.6 (14.6 – 21.6) 350

60 years and older 6.66 (6.02 – 7.37) 2.78 (2.23 – 3.04) 6.94 (5.82 – 7.73) 17.0 (15.2 – 18.8) 444

Females

Total, 6 years and older 7.05 (6.69 – 7.43) 2.94 (2.70 – 3.20) 7.04 (6.59 – 7.55) 16.6 (15.4 – 18.1) 1,492

6–11 years 8.11 (7.34 – 8.95) 3.85 (3.04 – 4.45) 8.14 (7.69 – 8.60) 15.0 (13.3 – 22.0) 118

12–19 years 6.84 (6.25 – 7.48) 3.57 (2.93 – 3.86) 6.57 (5.73 – 7.38) 14.0 (12.8 – 16.4) 244

20–39 years 6.86 (6.45 – 7.28) 2.92 (2.53 – 3.38) 6.73 (6.29 – 7.41) 15.7 (13.5 – 18.2) 402

40–59 years 6.87 (6.18 – 7.64) 2.84 (2.52 – 3.24) 6.84 (6.09 – 7.85) 16.5 (14.4 – 19.9) 329

60 years and older 7.39 (6.69 – 8.17) 2.73 (2.26 – 2.94) 7.50 (6.74 – 8.69) 19.5 (17.0 – 21.2) 399
152 2nd 152 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.9.b. Serum beta-cryptoxanthin: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 2001–2002 and 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2001–2002 7.46 (7.06 – 7.87) 2.45 (2.20 – 2.68) 7.40 (7.00 – 7.82) 23.0 (20.9 – 25.5) 7,890

 2005–2006 7.70 (7.34 – 8.08) 2.46 (2.26 – 2.63) 7.62 (7.24 – 7.99) 24.1 (22.5 – 26.4) 7,195

Age group

3–5 years

 2001–2002 9.43 (8.40 – 10.6) 3.30 (1.88 – 3.96) 9.09 (7.81 – 10.4) 30.7 (25.3 – 43.1) 427

6–11 years

 2001–2002 9.40 (8.71 – 10.2) 3.92 (3.28 – 4.22) 9.05 (8.29 – 10.2) 26.1 (21.9 – 31.6) 1,006

 2005–2006 9.47 (8.88 – 10.1) 3.90 (3.32 – 4.23) 9.14 (8.52 – 9.66) 24.9 (23.0 – 28.7) 855

12–19 years

 2001–2002 7.63 (7.20 – 8.08) 3.05 (2.58 – 3.31) 7.45 (7.00 – 7.99) 19.8 (18.5 – 22.3) 2,199

 2005–2006 7.82 (7.42 – 8.23) 3.20 (2.91 – 3.50) 7.49 (7.01 – 7.99) 20.3 (18.8 – 23.4) 1,924

20–39 years

 2001–2002 7.11 (6.57 – 7.69) 2.40 (2.04 – 2.73) 6.83 (6.25 – 7.50) 22.9 (20.0 – 26.6) 1,707

 2005–2006 7.95 (7.52 – 8.40) 2.78 (2.50 – 2.97) 7.81 (7.31 – 8.18) 24.5 (21.7 – 28.8) 1,679

40–59 years

 2001–2002 7.28 (6.75 – 7.86) 2.39 (2.02 – 2.71) 7.16 (6.66 – 7.77) 23.2 (20.4 – 26.1) 1,459

 2005–2006 7.24 (6.60 – 7.94) 2.16 (1.80 – 2.40) 7.03 (6.50 – 7.82) 24.8 (21.5 – 29.2) 1,357

60 years and older

 2001–2002 7.44 (6.84 – 8.09) 1.94 (1.71 – 2.22) 7.64 (7.06 – 8.28) 23.5 (20.9 – 27.8) 1,519

 2005–2006 7.39 (6.86 – 7.97) 1.98 (1.62 – 2.25) 7.48 (7.03 – 8.13) 24.2 (22.7 – 27.6) 1,380

Gender

(6 years and older)

Males

 2001–2002 7.28 (6.89 – 7.69) 2.41 (2.10 – 2.66) 7.32 (6.82 – 7.81) 22.3 (20.4 – 25.0) 3,815

 2005–2006 7.51 (7.10 – 7.94) 2.41 (2.10 – 2.70) 7.49 (7.12 – 7.88) 22.8 (21.5 – 25.0) 3,514

Females

 2001–2002 7.63 (7.20 – 8.08) 2.48 (2.29 – 2.75) 7.45 (7.05 – 7.84) 23.8 (21.1 – 26.2) 4,075

 2005–2006 7.89 (7.53 – 8.27) 2.54 (2.24 – 2.69) 7.74 (7.28 – 8.14) 25.5 (23.4 – 28.1) 3,681

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 12.1 (11.2 – 13.2) 4.14 (3.71 – 4.53) 12.1 (10.9 – 13.5) 34.5 (32.1 – 38.5) 1,988

 2005–2006 13.0 (11.8 – 14.3) 4.42 (3.87 – 4.86) 12.9 (11.9 – 14.2) 36.2 (32.4 – 45.4) 1,842

Non-Hispanic Blacks

 2001–2002 8.03 (7.38 – 8.74) 2.99 (2.66 – 3.27) 7.92 (7.32 – 8.55) 23.0 (19.9 – 27.7) 1,859

 2005–2006 8.34 (7.88 – 8.84) 2.89 (2.59 – 3.11) 8.23 (7.80 – 8.81) 23.6 (20.8 – 27.8) 1,848

Non-Hispanic Whites

 2001–2002 6.80 (6.43 – 7.19) 2.36 (2.05 – 2.53) 6.71 (6.29 – 7.16) 19.6 (18.2 – 22.2) 3,422

 2005–2006 6.94 (6.59 – 7.32) 2.26 (2.07 – 2.44) 6.96 (6.62 – 7.38) 20.5 (19.7 – 21.9) 2,960
Figure 2.9.b. Serum beta−cryptoxanthin: Concentrations by survey cycle 

Selected percentiles in μg/dL (95% confidence intervals), National Health and 


Nutrition Examination Survey, 2001–2002 and 2005–2006
 

50 

5th Percentile 50th Percentile 95th Percentile

40 

30 

20 

10 

16 

14 

12 

10 

8 

6 

5 

4 

3 

2 

1 

1 1 

1 

1 1 

1 1 

1 1 

1 1 1 

1 

1 

1 

1 1 

1 1 

1 1 

1 1 1 

1 1 1 1 1 1 1 1 

1 

1 

1 1 

1 1 

1 1 

1 

1 1 

1 1 

1 1 1 1 1 1 

1 

1 

1 1 

1 1 

01−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) (6+y) (6+y) (6+y) (6+y) (6+y) 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 153153
154

2nd 154 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.10.a.1. Serum lutein/zeaxanthin: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 13.8 (13.4 – 14.2) 4.95 (4.69 – 5.19) 5.90 (5.68 – 6.18) 13.7 (13.2 – 14.1) 31.3 (30.3 – 33.2) 38.5 (37.0 – 40.0) 7,254 Age group 6–11 years 13.1 (12.6 – 13.7) 5.74 (4.13 – 6.47) 6.70 (5.50 – 7.67) 13.3 (12.8 – 13.9) 24.5 (23.5 – 27.4) 29.0 (27.3 – 30.2) 860 12–19 years 10.7 (10.3 – 11.1) 4.91 (4.39 – 5.18) 5.67 (5.21 – 5.91) 10.6 (10.0 – 11.1) 20.0 (19.1 – 21.1) 22.7 (21.4 – 25.1) 1,954 20–39 years 13.6 (13.1 – 14.1) 4.94 (4.24 – 5.46) 5.91 (5.19 – 6.41) 13.6 (12.9 – 14.4) 29.3 (27.7 – 32.1) 35.2 (31.7 – 40.0) 1,688 40–59 years 14.5 (13.8 – 15.2) 4.62 (4.02 – 5.31) 5.82 (5.28 – 6.13) 14.5 (13.7 – 15.2) 35.7 (33.3 – 37.8) 40.8 (38.5 – 46.1) 1,365 60 years and older 15.5 (14.9 – 16.2) 5.27 (4.72 – 5.83) 6.44 (6.02 – 6.69) 15.7 (15.0 – 16.5) 35.9 (32.8 – 40.3) 42.5 (39.7 – 51.2) 1,387 Gender Males 13.6 (13.1 – 14.0) 4.92 (4.48 – 5.30) 5.93 (5.42 – 6.35) 13.5 (13.0 – 14.1) 30.7 (28.7 – 31.4) 35.7 (33.3 – 39.0) 3,547 Females 14.0 (13.5 – 14.4) 4.98 (4.62 – 5.26) 5.89 (5.69 – 6.13) 13.8 (13.3 – 14.4) 32.8 (31.0 – 35.7) 39.9 (38.4 – 41.5) 3,707 Race/ethnicity Mexican Americans 15.1 (14.5 – 15.8) 6.36 (5.62 – 6.79) 7.41 (6.79 – 7.83) 15.0 (14.4 – 15.6) 31.3 (29.2 – 34.1) 35.5 (33.2 – 40.8) 1,844 Non-Hispanic Blacks 15.3 (14.8 – 15.8) 5.88 (5.20 – 6.37) 7.03 (6.33 – 7.71) 15.4 (15.0 – 15.8) 31.5 (29.4 – 35.1) 38.0 (34.8 – 41.7) 1,891 Non-Hispanic Whites 13.2 (12.8 – 13.6) 4.74 (4.46 – 4.96) 5.70 (5.33 – 5.88) 12.9 (12.5 – 13.4) 30.9 (29.1 – 32.8) 37.5 (34.4 – 39.9) 2,973
6−11 12−19 20−39 40−59 60+ 

Serum lutein/zeaxanthin

0 10 20 30 

(μg/dL) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

30 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.10.a. Serum lutein/zeaxanthin: Concentrations by age group 

Geometric Mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006 Serum lutein/zeaxanthin Serum lutein/zeaxanthin (μg/dL) (μg/dL) 0 10 20 30 0 10 20 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 155155
156 2nd 156 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.10.a.2. Serum lutein/zeaxanthin: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 13.8 (13.4 – 14.2) 7.24 (6.91 – 7.49) 13.7 (13.2 – 14.1) 26.5 (25.7 – 27.3) 7,254

6–11 years 13.1 (12.6 – 13.7) 7.93 (6.84 – 8.54) 13.3 (12.8 – 13.9) 20.7 (20.1 – 22.0) 860

12–19 years 10.7 (10.3 – 11.1) 6.50 (6.19 – 6.74) 10.6 (10.0 – 11.1) 17.6 (16.9 – 18.4) 1,954

20–39 years 13.6 (13.1 – 14.1) 7.40 (6.64 – 7.83) 13.6 (12.9 – 14.4) 25.1 (23.4 – 27.1) 1,688

40–59 years 14.5 (13.8 – 15.2) 7.23 (6.70 – 7.58) 14.5 (13.7 – 15.2) 29.4 (27.5 – 31.0) 1,365

60 years and older 15.5 (14.9 – 16.2) 7.89 (7.52 – 8.13) 15.7 (15.0 – 16.5) 29.0 (27.3 – 31.9) 1,387

Males

Total, 6 years and older 13.6 (13.1 – 14.0) 7.22 (6.78 – 7.61) 13.5 (13.0 – 14.1) 25.6 (24.5 – 26.2) 3,547

6–11 years 13.4 (12.7 – 14.1) 8.08 (7.62 – 8.69) 13.6 (12.5 – 14.2) 20.5 (19.0 – 22.5) 427

12–19 years 10.5 (10.1 – 10.9) 6.49 (6.06 – 6.86) 10.3 (9.91 – 10.9) 17.3 (16.7 – 18.3) 980

20–39 years 13.4 (12.8 – 14.0) 7.26 (6.51 – 7.96) 13.4 (12.8 – 14.2) 23.8 (22.4 – 26.0) 738

40–59 years 14.2 (13.4 – 15.0) 7.22 (5.99 – 7.90) 14.1 (13.1 – 15.1) 27.6 (26.6 – 31.0) 673

60 years and older 15.5 (14.7 – 16.4) 7.94 (7.26 – 8.26) 15.9 (15.2 – 17.0) 27.8 (26.2 – 31.2) 729

Females

Total, 6 years and older 14.0 (13.5 – 14.4) 7.27 (6.77 – 7.56) 13.8 (13.3 – 14.4) 27.5 (26.7 – 28.5) 3,707

6–11 years 12.9 (12.1 – 13.7) 7.63 (5.98 – 8.50) 13.1 (12.6 – 13.7) 21.4 (19.9 – 23.6) 433

12–19 years 10.9 (10.3 – 11.4) 6.52 (5.98 – 6.93) 10.8 (10.1 – 11.5) 18.0 (16.9 – 19.1) 974

20–39 years 13.8 (13.2 – 14.5) 7.42 (6.59 – 7.80) 13.8 (12.9 – 14.8) 25.7 (23.9 – 28.0) 950

40–59 years 14.7 (13.9 – 15.6) 7.17 (6.76 – 7.56) 15.0 (13.8 – 16.2) 29.6 (28.9 – 32.2) 692

60 years and older 15.6 (14.8 – 16.4) 7.80 (7.40 – 8.17) 15.6 (14.1 – 16.7) 29.8 (28.0 – 32.8) 658

Table 2.10.a.3. Serum lutein/zeaxanthin: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 15.1 (14.5 – 15.8) 8.60 (8.07 – 9.17) 15.0 (14.4 – 15.6) 26.8 (25.2 – 28.6) 1,844

6–11 years 13.2 (12.4 – 14.0) 8.43 (6.89 – 9.35) 13.3 (12.2 – 14.1) 21.1 (19.3 – 23.5) 295

12–19 years 12.1 (11.5 – 12.7) 7.64 (7.22 – 8.01) 12.3 (11.7 – 12.9) 18.9 (18.0 – 20.0) 646

20–39 years 15.4 (14.3 – 16.6) 8.96 (8.09 – 9.65) 15.4 (14.2 – 17.3) 26.2 (23.4 – 30.5) 449

40–59 years 17.2 (16.0 – 18.5) 9.78 (7.36 – 11.0) 17.2 (16.2 – 18.5) 30.4 (27.3 – 36.3) 246

60 years and older 18.6 (16.7 – 20.7) 9.96 (7.59 – 12.0) 18.7 (16.9 – 20.3) 32.2 (30.1 – 34.4) 208

Males

Total, 6 years and older 15.4 (14.5 – 16.3) 8.81 (8.00 – 9.51) 15.1 (14.4 – 16.0) 28.1 (25.6 – 31.1) 883

6–11 years 13.0 (12.1 – 13.9) 8.75 (6.33 – 9.71) 13.1 (12.1 – 13.9) 19.6 (17.5 – 22.0) 145

12–19 years 11.7 (11.0 – 12.5) 7.62 (6.85 – 8.20) 12.0 (10.9 – 12.9) 18.2 (17.4 – 19.2) 313

20–39 years 16.0 (14.6 – 17.5) 9.47 (8.02 – 10.1) 15.8 (14.9 – 17.4) 28.5 (24.2 – 33.1) 198

40–59 years 17.7 (15.7 – 19.9) 8.69 (5.55 – 11.6) 17.6 (16.1 – 19.9) 31.1 (27.0 – 52.1) 122

60 years and older 19.1 (16.0 – 22.7) 10.7† (6.38 – 12.2) 18.5 (14.5 – 25.4) 34.1† (29.9 – 45.4) 105

Females

Total, 6 years and older 14.9 (14.2 – 15.6) 8.46 (7.68 – 9.34) 14.7 (14.1 – 15.5) 24.4 (23.3 – 27.0) 961

6–11 years 13.4 (12.5 – 14.4) 7.94 (6.66 – 8.97) 13.6 (11.9 – 14.4) 23.4 (19.8 – 27.1) 150

12–19 years 12.5 (11.9 – 13.1) 7.61 (7.08 – 8.14) 12.8 (12.3 – 13.1) 19.7 (18.3 – 20.8) 333

20–39 years 14.7 (13.7 – 15.9) 8.18 (7.42 – 9.74) 14.7 (13.1 – 16.9) 23.1 (22.2 – 27.0) 251

40–59 years 16.7 (15.6 – 18.0) 10.1 (7.40 – 10.9) 16.6 (14.5 – 18.4) 28.6 (23.7 – 44.2) 124

60 years and older 18.2 (16.1 – 20.7) 9.82† (7.45 – 11.7) 18.8 (16.2 – 21.7) 30.6† (28.3 – 33.6) 103

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 157157

Table 2.10.a.4. Serum lutein/zeaxanthin: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 15.3 (14.8 – 15.8) 8.61 (8.21 – 9.04) 15.4 (15.0 – 15.8) 26.6 (25.2 – 28.4) 1,891

6–11 years 15.8 (15.3 – 16.4) 10.5 (9.30 – 11.0) 16.2 (15.6 – 16.8) 23.9 (22.5 – 27.4) 240

12–19 years 12.9 (12.3 – 13.5) 7.94 (7.37 – 8.38) 13.0 (12.1 – 13.7) 20.9 (19.5 – 22.1) 665

20–39 years 14.5 (13.7 – 15.3) 8.29 (6.74 – 9.45) 14.4 (13.5 – 15.4) 25.3 (24.0 – 28.3) 368

40–59 years 16.4 (15.5 – 17.4) 8.77 (7.81 – 9.51) 17.0 (15.8 – 18.2) 28.6 (26.6 – 30.2) 335

60 years and older 17.4 (16.0 – 19.1) 8.99 (8.24 – 10.1) 17.7 (16.0 – 19.1) 31.5 (27.1 – 36.5) 283

Males

Total, 6 years and older 15.4 (14.9 – 15.9) 8.69 (8.26 – 9.42) 15.6 (14.9 – 16.3) 26.6 (25.6 – 28.4) 949

6–11 years 15.9 (14.9 – 16.9) 11.1 (10.3 – 11.9) 15.9 (15.0 – 17.2) 23.1 (21.9 – 26.9) 128

12–19 years 13.1 (12.4 – 13.8) 8.08 (7.27 – 8.68) 13.3 (12.2 – 14.6) 20.8 (19.6 – 21.9) 343

20–39 years 14.6 (13.8 – 15.5) 8.48 (6.56 – 9.65) 14.2 (13.1 – 15.7) 26.3 (23.2 – 29.1) 170

40–59 years 16.9 (15.8 – 18.1) 9.21 (7.66 – 9.97) 18.2 (15.6 – 19.3) 30.6 (27.5 – 36.0) 156

60 years and older 17.1 (16.2 – 18.1) 8.83 (7.79 – 9.64) 17.9 (17.2 – 18.8) 29.0 (25.9 – 34.0) 152

Females

Total, 6 years and older 15.2 (14.5 – 15.8) 8.51 (7.69 – 9.12) 15.3 (14.8 – 15.9) 26.4 (24.6 – 29.1) 942

6–11 years 15.8 (15.1 – 16.5) 9.57 (7.86 – 10.7) 16.5 (14.8 – 17.1) 24.0 (22.3 – 28.9) 112

12–19 years 12.7 (11.9 – 13.6) 7.70 (6.62 – 8.68) 12.7 (11.4 – 13.6) 21.1 (19.1 – 23.5) 322

20–39 years 14.4 (13.4 – 15.5) 8.03 (5.21 – 9.63) 14.7 (13.6 – 15.4) 24.6 (23.2 – 28.5) 198

40–59 years 16.0 (15.0 – 17.1) 8.72 (7.23 – 9.34) 16.6 (15.6 – 17.6) 26.9 (24.6 – 29.9) 179

60 years and older 17.7 (15.2 – 20.5) 9.08 (7.95 – 10.6) 17.3 (15.1 – 20.2) 33.2 (26.3 – 57.9) 131

Table 2.10.a.5. Serum lutein/zeaxanthin: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 13.2 (12.8 – 13.6) 6.80 (6.48 – 7.16) 12.9 (12.5 – 13.4) 25.8 (25.1 – 26.9) 2,973

6–11 years 12.5 (11.8 – 13.3) 7.68 (6.04 – 8.34) 12.7 (12.2 – 13.6) 19.8 (18.3 – 23.1) 231

12–19 years 9.88 (9.46 – 10.3) 6.16 (5.75 – 6.48) 9.80 (9.34 – 10.3) 16.2 (15.0 – 17.1) 499

20–39 years 12.7 (12.2 – 13.1) 6.56 (5.93 – 7.39) 12.4 (11.7 – 13.2) 23.6 (22.1 – 26.9) 714

40–59 years 13.8 (13.0 – 14.6) 6.87 (6.26 – 7.25) 13.7 (12.6 – 15.1) 27.9 (26.7 – 30.2) 683

60 years and older 15.0 (14.4 – 15.7) 7.59 (7.25 – 7.97) 15.2 (14.2 – 15.8) 28.5 (26.4 – 31.4) 846

Males

Total, 6 years and older 13.0 (12.5 – 13.4) 6.87 (6.45 – 7.22) 12.8 (12.2 – 13.5) 24.4 (23.5 – 25.7) 1,472

6–11 years 12.9 (11.8 – 14.2) 7.95 (5.77 – 8.67) 13.0 (12.2 – 14.1) 18.9 (17.1 – 31.9) 112

12–19 years 9.75 (9.24 – 10.3) 6.23 (5.55 – 6.75) 9.71 (9.33 – 10.0) 15.6 (14.3 – 16.9) 254

20–39 years 12.4 (11.9 – 12.9) 6.55 (5.75 – 7.69) 12.3 (11.7 – 13.0) 22.7 (21.8 – 24.8) 309

40–59 years 13.6 (12.8 – 14.4) 6.96 (5.83 – 7.71) 13.4 (12.3 – 14.9) 26.6 (24.5 – 29.9) 351

60 years and older 15.0 (14.2 – 15.9) 7.59 (7.11 – 8.05) 15.4 (14.4 – 16.5) 26.6 (25.5 – 30.6) 446

Females

Total, 6 years and older 13.4 (12.9 – 13.8) 6.75 (6.20 – 7.26) 13.0 (12.4 – 13.7) 27.4 (26.0 – 28.1) 1,501

6–11 years 12.1 (11.1 – 13.2) 6.73 (5.07 – 8.32) 12.4 (11.1 – 13.2) 19.9 (18.2 – 28.1) 119

12–19 years 10.0 (9.21 – 10.9) 6.08 (5.23 – 6.57) 9.90 (9.18 – 11.1) 16.5 (15.3 – 18.1) 245

20–39 years 12.9 (12.2 – 13.6) 6.60 (5.82 – 7.42) 12.6 (11.2 – 14.4) 25.0 (22.3 – 28.5) 405

40–59 years 14.0 (13.0 – 15.0) 6.78 (5.98 – 7.28) 14.0 (12.5 – 15.7) 29.2 (27.5 – 30.7) 332

60 years and older 15.1 (14.3 – 15.9) 7.58 (6.96 – 8.05) 14.7 (13.6 – 16.2) 29.2 (27.6 – 32.6) 400
158 2nd 158 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.10.b. Serum lutein/zeaxanthin: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 2001–2002 and 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2001–2002 13.1 (12.5 – 13.6) 5.77 (5.53 – 6.00) 12.9 (12.2 – 13.5) 30.4 (28.6 – 32.2) 7,923

 2005–2006 13.8 (13.4 – 14.2) 5.90 (5.68 – 6.18) 13.7 (13.2 – 14.1) 31.3 (30.3 – 33.2) 7,254

Age group

3–5 years

 2001–2002 12.5 (11.8 – 13.2) 6.38 (5.82 – 7.04) 12.5 (12.0 – 13.1) 24.6 (22.2 – 31.5) 430

6–11 years

 2001–2002 12.5 (11.9 – 13.2) 6.61 (5.88 – 7.06) 12.3 (11.6 – 13.1) 24.8 (22.4 – 26.0) 1,014

 2005–2006 13.1 (12.6 – 13.7) 6.70 (5.50 – 7.67) 13.3 (12.8 – 13.9) 24.5 (23.5 – 27.4) 860

12–19 years

 2001–2002 10.4 (9.91 – 11.0) 4.99 (4.64 – 5.54) 10.4 (9.80 – 11.0) 20.9 (19.4 – 23.2) 2,205

 2005–2006 10.7 (10.3 – 11.1) 5.67 (5.21 – 5.91) 10.6 (10.0 – 11.1) 20.0 (19.1 – 21.1) 1,954

20–39 years

 2001–2002 12.1 (11.5 – 12.9) 5.47 (5.16 – 5.73) 12.0 (11.2 – 12.7) 27.1 (25.7 – 30.7) 1,714

 2005–2006 13.6 (13.1 – 14.1) 5.91 (5.19 – 6.41) 13.6 (12.9 – 14.4) 29.3 (27.7 – 32.1) 1,688

40–59 years

 2001–2002 14.4 (13.6 – 15.2) 6.47 (5.69 – 7.04) 14.1 (13.5 – 14.9) 32.6 (31.0 – 35.5) 1,468

 2005–2006 14.5 (13.8 – 15.2) 5.82 (5.28 – 6.13) 14.5 (13.7 – 15.2) 35.7 (33.3 – 37.8) 1,365

60 years and older

 2001–2002 15.2 (14.3 – 16.2) 6.14 (5.54 – 6.68) 15.3 (14.3 – 16.6) 35.1 (33.3 – 41.0) 1,522

 2005–2006 15.5 (14.9 – 16.2) 6.44 (6.02 – 6.69) 15.7 (15.0 – 16.5) 35.9 (32.8 – 40.3) 1,387

Gender

(6 years and older)

Males

 2001–2002 13.0 (12.5 – 13.6) 5.67 (5.35 – 6.01) 13.0 (12.4 – 13.6) 29.8 (28.3 – 31.7) 3,832

 2005–2006 13.6 (13.1 – 14.0) 5.93 (5.42 – 6.35) 13.5 (13.0 – 14.1) 30.7 (28.7 – 31.4) 3,547

Females

 2001–2002 13.1 (12.5 – 13.7) 5.87 (5.59 – 6.03) 12.7 (12.1 – 13.5) 31.4 (28.8 – 33.0) 4,091

 2005–2006 14.0 (13.5 – 14.4) 5.89 (5.69 – 6.13) 13.8 (13.3 – 14.4) 32.8 (31.0 – 35.7) 3,707

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 13.7 (13.3 – 14.2) 6.58 (6.15 – 6.84) 13.6 (13.2 – 14.1) 28.5 (26.8 – 30.7) 1,988

 2005–2006 15.1 (14.5 – 15.8) 7.41 (6.79 – 7.83) 15.0 (14.4 – 15.6) 31.3 (29.2 – 34.1) 1,844

Non-Hispanic Blacks

 2001–2002 14.2 (13.1 – 15.5) 6.80 (6.20 – 7.20) 14.1 (12.8 – 15.5) 30.7 (28.5 – 34.6) 1,864

 2005–2006 15.3 (14.8 – 15.8) 7.03 (6.33 – 7.71) 15.4 (15.0 – 15.8) 31.5 (29.4 – 35.1) 1,891

Non-Hispanic Whites

 2001–2002 12.6 (12.0 – 13.2) 5.60 (5.14 – 5.90) 12.4 (11.7 – 13.1) 28.8 (27.2 – 31.8) 3,447

 2005–2006 13.2 (12.8 – 13.6) 5.70 (5.33 – 5.88) 12.9 (12.5 – 13.4) 30.9 (29.1 – 32.8) 2,973
5th Percentile 50th Percentile 95th Percentile

35 

30 

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01−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) (6+y) (6+y) (6+y) (6+y) (6+y) 

Figure 2.10.b. Serum lutein/zeaxanthin: Concentrations by survey cycle 

Selected percentiles in μg/dL (95% confidence intervals), National Health and 


Nutrition Examination Survey, 2001–2002 and 2005–2006
 

40 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 159159
160

2nd 160 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.11.a.1. Serum trans-lycopene: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 21.2 (20.7 – 21.7) 5.64 (4.99 – 6.25) 7.81 (7.33 – 8.40) 22.7 (22.2 – 23.2) 43.6 (42.4 – 44.9) 48.4 (47.5 – 49.8) 7,254 Age group 6–11 years 21.7 (20.5 – 22.9) 7.67 (5.27 – 9.29) 9.48 (7.38 – 10.9) 22.5 (21.1 – 23.7) 42.8 (40.0 – 46.0) 46.1 (44.0 – 54.8) 860 12–19 years 21.9 (21.1 – 22.6) 8.42 (7.31 – 8.78) 9.91 (8.98 – 11.0) 22.3 (21.8 – 22.9) 42.6 (40.2 – 45.1) 46.8 (44.4 – 52.7) 1,954 20–39 years 23.9 (23.3 – 24.4) 8.24 (7.38 – 8.96) 10.7 (8.97 – 11.4) 25.1 (24.3 – 25.6) 46.1 (44.1 – 47.2) 51.6 (48.9 – 53.5) 1,688 40–59 years 21.6 (20.4 – 22.8) 5.13 (3.76 – 6.34) 7.69 (6.02 – 8.98) 23.2 (22.1 – 24.4) 44.6 (42.5 – 47.1) 50.0 (47.2 – 55.9) 1,365 60 years and older 16.4 (15.4 – 17.4) 3.75 (2.69 – 4.36) 5.19 (4.32 – 5.97) 17.8 (16.8 – 19.0) 38.8 (37.3 – 40.7) 44.4 (40.7 – 46.5) 1,387 Gender Males 21.8 (21.0 – 22.6) 5.79 (4.54 – 6.70) 7.85 (6.99 – 8.89) 23.4 (22.6 – 24.3) 44.7 (43.7 – 47.0) 52.1 (49.0 – 55.7) 3,547 Females 20.6 (20.0 – 21.2) 5.47 (4.93 – 6.39) 7.76 (7.09 – 8.40) 22.2 (21.5 – 22.6) 42.3 (41.2 – 43.9) 46.3 (45.1 – 48.8) 3,707 Race/ethnicity Mexican Americans 19.5 (19.1 – 20.0) 7.04 (6.09 – 7.33) 8.80 (7.83 – 9.29) 20.2 (19.6 – 20.9) 38.0 (36.4 – 40.2) 42.5 (39.8 – 49.9) 1,844 Non-Hispanic Blacks 22.0 (20.9 – 23.2) 6.29 (5.46 – 6.99) 8.11 (7.39 – 8.77) 23.5 (22.6 – 24.7) 47.0 (44.7 – 49.5) 53.5 (51.0 – 57.3) 1,891 Non-Hispanic Whites 21.3 (20.8 – 21.9) 5.46 (4.83 – 6.26) 7.69 (7.04 – 8.47) 23.0 (22.4 – 23.5) 43.8 (42.4 – 45.2) 48.5 (47.3 – 50.6) 2,973
6−11 12−19 20−39 40−59 60+ 

0 10 20 30 

Serum trans−lycopene (μg/dL) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

30 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.11.a. Serum trans−lycopene: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006 Serum trans−lycopene Serum trans−lycopene (μg/dL) (μg/dL) 0 10 20 30 0 10 20 

6−11 12−19 20−39 

Females 

40−59 60+ 6−11 12−19 20−39 

Males 

40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

6−11 12−19 

Age (years) 

20−39 40−59 60+ 6−11 12−19 

Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 161161
162 2nd 162 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

 Table 2.11.a.2. Serum trans-lycopene: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 21.2 (20.7 – 21.7) 10.7 (10.1 – 11.3) 22.7 (22.2 – 23.2) 38.9 (37.7 – 39.8) 7,254

6–11 years 21.7 (20.5 – 22.9) 11.6 (10.5 – 12.9) 22.5 (21.1 – 23.7) 38.3 (36.3 – 40.3) 860

12–19 years 21.9 (21.1 – 22.6) 12.9 (12.2 – 13.6) 22.3 (21.8 – 22.9) 37.2 (35.8 – 39.1) 1,954

20–39 years 23.9 (23.3 – 24.4) 13.4 (11.8 – 14.8) 25.1 (24.3 – 25.6) 40.2 (39.5 – 41.2) 1,688

40–59 years 21.6 (20.4 – 22.8) 11.0 (9.50 – 11.9) 23.2 (22.1 – 24.4) 39.9 (38.4 – 41.8) 1,365

60 years and older 16.4 (15.4 – 17.4) 7.14 (6.48 – 7.69) 17.8 (16.8 – 19.0) 33.7 (32.3 – 36.1) 1,387

Males

Total, 6 years and older 21.8 (21.0 – 22.6) 11.2 (10.3 – 11.8) 23.4 (22.6 – 24.3) 39.6 (38.1 – 41.0) 3,547

6–11 years 22.6 (21.4 – 23.9) 12.8 (11.0 – 14.4) 23.1 (21.8 – 24.3) 38.6 (36.9 – 40.8) 427

12–19 years 22.2 (21.4 – 23.0) 13.4 (11.5 – 14.2) 22.7 (22.0 – 23.6) 37.2 (36.3 – 38.7) 980

20–39 years 25.1 (24.0 – 26.2) 14.6 (11.9 – 15.8) 26.2 (24.9 – 27.4) 41.4 (40.0 – 43.7) 738

40–59 years 21.9 (20.1 – 23.9) 10.9 (8.58 – 12.4) 23.9 (22.3 – 25.6) 40.6 (37.3 – 43.9) 673

60 years and older 16.3 (15.1 – 17.6) 7.44 (6.33 – 7.78) 17.8 (16.4 – 19.1) 33.5 (31.3 – 36.8) 729

Females

Total, 6 years and older 20.6 (20.0 – 21.2) 10.3 (9.56 – 11.1) 22.2 (21.5 – 22.6) 38.2 (36.7 – 39.5) 3,707

6–11 years 20.8 (18.9 – 22.8) 10.4 (8.68 – 12.8) 21.7 (20.3 – 23.5) 37.3 (35.2 – 41.9) 433

12–19 years 21.5 (20.1 – 23.0) 12.8 (10.7 – 13.7) 21.9 (21.0 – 23.2) 37.1 (34.6 – 40.6) 974

20–39 years 22.7 (22.1 – 23.3) 12.9 (11.1 – 14.2) 23.7 (23.0 – 24.6) 39.0 (35.9 – 41.3) 950

40–59 years 21.3 (20.1 – 22.5) 11.0 (9.50 – 11.9) 22.4 (21.0 – 24.3) 39.3 (38.6 – 40.8) 692

60 years and older 16.4 (15.3 – 17.6) 6.89 (6.29 – 7.73) 17.9 (16.6 – 19.3) 34.2 (31.5 – 38.3) 658

Table 2.11.a.3. Serum trans-lycopene: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 19.5 (19.1 – 20.0) 10.7 (10.1 – 11.2) 20.2 (19.6 – 20.9) 33.7 (32.8 – 34.4) 1,844

6–11 years 19.6 (18.5 – 20.8) 11.0 (9.47 – 13.0) 20.1 (19.1 – 21.2) 32.4 (31.2 – 34.0) 295

12–19 years 20.0 (19.2 – 20.9) 12.0 (10.1 – 12.8) 20.9 (19.8 – 22.1) 33.5 (32.3 – 35.2) 646

20–39 years 20.9 (19.7 – 22.1) 11.6 (9.65 – 13.5) 22.0 (21.0 – 23.3) 34.7 (33.4 – 38.1) 449

40–59 years 18.4 (17.3 – 19.5) 10.0 (9.04 – 11.0) 18.8 (18.2 – 19.4) 32.8 (30.6 – 37.0) 246

60 years and older 15.5 (14.0 – 17.1) 7.71 (5.24 – 8.87) 16.1 (14.7 – 17.7) 28.6 (26.1 – 33.2) 208

Males

Total, 6 years and older 20.1 (19.4 – 20.8) 11.0 (9.96 – 12.0) 21.1 (20.1 – 22.2) 34.4 (32.2 – 37.6) 883

6–11 years 19.0 (17.8 – 20.2) 10.9 (9.33 – 12.7) 19.5 (18.2 – 20.5) 32.1 (28.9 – 36.1) 145

12–19 years 20.6 (19.2 – 22.1) 12.3 (8.72 – 13.6) 22.1 (19.9 – 23.4) 34.0 (32.7 – 35.5) 313

20–39 years 21.9 (20.0 – 23.9) 13.2 (8.92 – 15.1) 23.1 (21.5 – 24.9) 35.1 (32.1 – 44.4) 198

40–59 years 18.6 (17.1 – 20.2) 10.1 (7.36 – 11.3) 19.3 (17.8 – 20.7) 32.7 (28.9 – 39.9) 122

60 years and older 15.5 (12.9 – 18.6) 7.41† (2.71 – 8.77) 16.2 (13.9 – 19.3) 31.3† (25.2 – 56.0) 105

Females

Total, 6 years and older 19.0 (18.4 – 19.5) 10.5 (10.0 – 11.0) 19.4 (18.5 – 20.2) 33.3 (32.1 – 34.1) 961

6–11 years 20.4 (18.9 – 22.0) 11.4 (9.53 – 13.4) 21.2 (19.3 – 23.0) 32.5 (31.2 – 35.0) 150

12–19 years 19.4 (18.6 – 20.3) 11.8 (10.1 – 12.2) 20.0 (19.4 – 20.9) 32.9 (31.5 – 35.7) 333

20–39 years 19.7 (18.6 – 20.8) 10.8 (9.95 – 12.7) 20.0 (18.5 – 23.4) 34.1 (32.5 – 36.7) 251

40–59 years 18.1 (16.8 – 19.6) 10.0 (9.01 – 11.0) 18.0 (16.9 – 19.1) 32.8 (30.5 – 34.5) 124

60 years and older 15.5 (14.0 – 17.2) 7.98† (5.24 – 10.5) 16.0 (13.3 – 18.1) 26.7† (25.0 – 31.2) 103

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 163163

Table 2.11.a.4. Serum trans-lycopene: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 22.0 (20.9 – 23.2) 10.8 (9.77 – 11.8) 23.5 (22.6 – 24.7) 40.0 (39.1 – 41.7) 1,891

6–11 years 25.6 (23.3 – 28.2) 13.7 (11.1 – 17.0) 27.0 (24.6 – 28.9) 41.8 (38.7 – 45.9) 240

12–19 years 24.8 (23.5 – 26.2) 14.3 (12.9 – 15.4) 25.8 (23.6 – 27.4) 41.6 (39.1 – 44.9) 665

20–39 years 25.7 (24.2 – 27.2) 14.5 (12.4 – 15.6) 26.3 (25.0 – 27.8) 42.4 (39.6 – 47.1) 368

40–59 years 20.4 (19.1 – 21.8) 9.89 (8.68 – 10.8) 21.3 (19.9 – 23.3) 38.6 (36.2 – 43.4) 335

60 years and older 14.3 (13.1 – 15.7) 6.20 (4.94 – 6.93) 15.3 (14.5 – 16.5) 31.2 (27.5 – 35.7) 283

Males

Total, 6 years and older 23.1 (21.9 – 24.3) 11.2 (9.87 – 12.4) 24.9 (23.3 – 26.4) 41.8 (39.8 – 44.9) 949

6–11 years 26.2 (23.4 – 29.2) 16.4 (10.4 – 18.0) 27.0 (23.4 – 29.8) 40.1 (38.4 – 46.3) 128

12–19 years 25.5 (24.1 – 27.0) 14.9 (13.5 – 16.1) 26.2 (23.9 – 27.8) 43.2 (39.5 – 51.7) 343

20–39 years 28.0 (26.5 – 29.6) 15.3 (13.6 – 16.8) 27.9 (26.2 – 30.2) 47.8 (42.5 – 52.7) 170

40–59 years 20.5 (18.3 – 22.9) 9.19 (6.70 – 10.9) 22.1 (18.9 – 26.4) 38.6 (35.6 – 51.3) 156

60 years and older 14.6 (13.3 – 15.9) 5.56 (4.94 – 6.14) 15.5 (15.0 – 17.1) 32.1 (30.0 – 38.1) 152

Females

Total, 6 years and older 21.2 (19.8 – 22.7) 10.6 (9.30 – 11.6) 22.5 (21.1 – 23.7) 39.0 (37.2 – 41.0) 942

6–11 years 25.1 (22.4 – 28.1) 12.4 (9.15 – 15.1) 26.7 (24.9 – 28.9) 42.1 (38.4 – 49.7) 112

12–19 years 24.1 (21.9 – 26.6) 13.9 (10.5 – 15.5) 24.8 (22.1 – 27.6) 39.8 (36.6 – 43.9) 322

20–39 years 23.8 (21.8 – 26.1) 13.6 (10.9 – 15.7) 25.0 (22.1 – 27.2) 39.1 (37.4 – 41.6) 198

40–59 years 20.3 (19.2 – 21.6) 9.99 (9.03 – 11.3) 20.9 (18.1 – 23.3) 39.0 (34.8 – 44.3) 179

60 years and older 14.1 (12.1 – 16.5) 6.71 (3.54 – 7.89) 15.0 (13.0 – 17.4) 28.1 (24.6 – 39.1) 131

Table 2.11.a.5. Serum trans-lycopene: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 21.3 (20.8 – 21.9) 10.8 (10.1 – 11.3) 23.0 (22.4 – 23.5) 39.1 (37.5 – 40.6) 2,973

6–11 years 21.4 (19.6 – 23.4) 11.1 (9.63 – 12.9) 22.1 (20.4 – 24.0) 37.5 (33.7 – 42.4) 231

12–19 years 21.6 (20.6 – 22.6) 13.0 (11.1 – 13.7) 22.1 (21.4 – 22.7) 37.0 (35.0 – 39.9) 499

20–39 years 24.6 (23.6 – 25.6) 13.7 (11.4 – 16.4) 25.6 (24.8 – 26.4) 40.7 (39.6 – 42.3) 714

40–59 years 22.3 (20.9 – 23.9) 11.7 (9.54 – 13.0) 24.2 (22.9 – 25.3) 40.5 (38.3 – 42.2) 683

60 years and older 16.6 (15.6 – 17.6) 7.32 (6.45 – 8.11) 18.0 (16.9 – 19.2) 34.2 (32.3 – 37.0) 846

Males

Total, 6 years and older 21.9 (21.0 – 22.9) 11.3 (10.3 – 11.9) 23.6 (22.7 – 24.8) 39.6 (37.9 – 41.6) 1,472

6–11 years 22.6 (20.7 – 24.6) 12.8 (8.41 – 14.9) 23.0 (21.1 – 24.8) 38.3 (33.4 – 43.2) 112

12–19 years 21.8 (20.6 – 23.2) 13.2 (10.0 – 14.3) 22.5 (21.1 – 24.3) 36.6 (35.8 – 38.4) 254

20–39 years 25.7 (24.2 – 27.2) 14.8 (11.8 – 17.1) 26.5 (25.1 – 28.4) 41.5 (39.6 – 46.1) 309

40–59 years 22.8 (20.6 – 25.2) 11.8 (8.02 – 14.0) 25.0 (23.2 – 27.0) 41.2 (38.1 – 44.0) 351

60 years and older 16.3 (15.0 – 17.8) 7.49 (6.36 – 8.08) 17.7 (16.0 – 19.2) 33.7 (31.3 – 37.0) 446

Females

Total, 6 years and older 20.8 (20.0 – 21.7) 10.2 (9.48 – 11.1) 22.4 (21.5 – 23.1) 38.5 (36.5 – 40.3) 1,501

6–11 years 20.1 (17.6 – 23.1) 9.66 (4.60 – 12.9) 20.7 (19.2 – 23.2) 36.7 (30.8 – 50.0) 119

12–19 years 21.3 (19.4 – 23.3) 12.7 (9.21 – 14.2) 21.6 (20.3 – 23.5) 37.2 (33.9 – 41.5) 245

20–39 years 23.5 (22.5 – 24.5) 13.0 (10.2 – 16.2) 24.6 (23.3 – 25.3) 40.2 (35.9 – 42.7) 405

40–59 years 21.8 (20.3 – 23.6) 11.7 (9.46 – 12.9) 23.4 (21.4 – 25.3) 39.7 (37.9 – 41.1) 332

60 years and older 16.9 (15.8 – 18.0) 7.00 (6.17 – 8.28) 18.3 (17.1 – 20.1) 34.4 (32.1 – 38.5) 400
164 2nd 164 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.11.b. Serum trans-lycopene: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the U.S. population, National 

Health and Nutrition Examination Survey, 2001–2002 and 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2001–2002 20.6 (19.9 – 21.3) 7.87 (7.49 – 8.27) 22.2 (21.3 – 23.1) 42.5 (41.0 – 43.9) 7,921

 2005–2006 21.2 (20.7 – 21.7) 7.81 (7.33 – 8.40) 22.7 (22.2 – 23.2) 43.6 (42.4 – 44.9) 7,254

Age group

3–5 years

 2001–2002 16.1 (15.2 – 17.1) 6.16 (3.73 – 7.47) 17.3 (16.2 – 18.1) 33.9 (32.8 – 37.9) 427

6–11 years

 2001–2002 21.6 (20.7 – 22.5) 9.31 (8.20 – 9.83) 22.7 (21.4 – 23.6) 40.5 (37.7 – 47.0) 1,012

 2005–2006 21.7 (20.5 – 22.9) 9.48 (7.38 – 10.9) 22.5 (21.1 – 23.7) 42.8 (40.0 – 46.0) 860

12–19 years

 2001–2002 21.6 (21.1 – 22.1) 10.5 (9.69 – 11.1) 22.2 (21.8 – 22.7) 40.5 (38.1 – 43.2) 2,205

 2005–2006 21.9 (21.1 – 22.6) 9.91 (8.98 – 11.0) 22.3 (21.8 – 22.9) 42.6 (40.2 – 45.1) 1,954

20–39 years

 2001–2002 22.7 (21.5 – 23.9) 10.3 (9.02 – 11.5) 23.7 (22.5 – 24.9) 44.9 (42.4 – 47.1) 1,714

 2005–2006 23.9 (23.3 – 24.4) 10.7 (8.97 – 11.4) 25.1 (24.3 – 25.6) 46.1 (44.1 – 47.2) 1,688

40–59 years

 2001–2002 21.1 (20.1 – 22.1) 7.82 (7.02 – 8.61) 22.7 (21.4 – 24.1) 42.6 (41.2 – 43.8) 1,468

 2005–2006 21.6 (20.4 – 22.8) 7.69 (6.02 – 8.98) 23.2 (22.1 – 24.4) 44.6 (42.5 – 47.1) 1,365

60 years and older

 2001–2002 15.4 (14.6 – 16.3) 4.15 (2.92 – 5.13) 17.1 (16.1 – 17.9) 39.0 (36.4 – 41.3) 1,522

 2005–2006 16.4 (15.4 – 17.4) 5.19 (4.32 – 5.97) 17.8 (16.8 – 19.0) 38.8 (37.3 – 40.7) 1,387

Gender

(6 years and older)

Males

 2001–2002 21.4 (20.6 – 22.3) 8.02 (7.31 – 8.80) 23.3 (22.3 – 24.2) 44.2 (42.8 – 46.3) 3,832

 2005–2006 21.8 (21.0 – 22.6) 7.85 (6.99 – 8.89) 23.4 (22.6 – 24.3) 44.7 (43.7 – 47.0) 3,547

Females

 2001–2002 19.8 (19.2 – 20.5) 7.82 (7.13 – 8.34) 21.2 (20.4 – 22.0) 40.3 (38.9 – 42.1) 4,089

 2005–2006 20.6 (20.0 – 21.2) 7.76 (7.09 – 8.40) 22.2 (21.5 – 22.6) 42.3 (41.2 – 43.9) 3,707

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 20.0 (19.2 – 20.8) 8.89 (7.84 – 9.62) 20.7 (20.1 – 21.7) 39.8 (38.1 – 42.0) 1,987

 2005–2006 19.5 (19.1 – 20.0) 8.80 (7.83 – 9.29) 20.2 (19.6 – 20.9) 38.0 (36.4 – 40.2) 1,844

Non-Hispanic Blacks

 2001–2002 21.7 (21.0 – 22.3) 8.03 (6.83 – 9.11) 23.4 (22.2 – 24.3) 46.6 (44.9 – 49.0) 1,864

 2005–2006 22.0 (20.9 – 23.2) 8.11 (7.39 – 8.77) 23.5 (22.6 – 24.7) 47.0 (44.7 – 49.5) 1,891

Non-Hispanic Whites

 2001–2002 20.8 (20.1 – 21.6) 8.17 (7.55 – 8.72) 22.4 (21.3 – 23.5) 42.5 (40.9 – 44.0) 3,446

 2005–2006 21.3 (20.8 – 21.9) 7.69 (7.04 – 8.47) 23.0 (22.4 – 23.5) 43.8 (42.4 – 45.2) 2,973
5th Percentile 50th Percentile 95th Percentile

50 

45 

40 

35 

30 

25 

20 

15 

12 

10 

8 

6 

4 

2 

i 

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01−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−0601−0205−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) (6+y) (6+y) (6+y) (6+y) (6+y) 

Figure 2.11.b. Serum trans−lycopene: Concentrations by survey cycle 

Selected percentiles in μg/dL (95% confidence intervals), National Health and 


Nutrition Examination Survey, 2001–2002 and 2005–2006
 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 165165
166

2nd 166 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.12.a.1. Serum total lycopene: Concentrations Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 39.4 (38.5 – 40.2) 11.3 (10.4 – 12.6) 15.4 (14.6 – 16.1) 41.8 (41.0 – 42.6) 80.8 (78.8 – 82.5) 90.7 (87.9 – 94.7) 7,149 Age group 6–11 years 39.7 (37.5 – 42.0) 14.9 (10.7 – 17.8) 18.8 (15.1 – 19.9) 40.9 (38.5 – 44.1) 78.4 (74.8 – 82.5) 83.0 (80.6 – 105) 851 12–19 years 39.5 (38.2 – 40.8) 15.4 (12.9 – 17.4) 19.1 (17.2 – 20.9) 40.6 (39.6 – 42.0) 73.9 (71.5 – 79.0) 82.8 (78.1 – 93.4) 1,907 20–39 years 43.8 (42.7 – 44.9) 15.9 (14.0 – 17.8) 20.0 (17.0 – 21.8) 45.2 (43.8 – 46.6) 83.3 (81.4 – 86.1) 92.7 (87.4 – 99.3) 1,667 40–59 years 40.5 (38.2 – 42.9) 10.6 (7.35 – 13.2) 15.0 (12.4 – 17.1) 43.1 (41.1 – 45.3) 84.1 (79.9 – 89.2) 97.2 (90.7 – 103) 1,346 60 years and older 31.5 (29.8 – 33.2) 8.08 (6.96 – 9.57) 10.7 (9.50 – 12.4) 33.5 (31.4 – 35.9) 72.8 (69.5 – 76.4) 81.7 (76.3 – 89.4) 1,378 Gender Males 40.6 (39.3 – 42.0) 11.4 (9.28 – 13.2) 15.6 (13.9 – 17.3) 43.5 (42.2 – 44.7) 84.5 (81.6 – 86.9) 95.2 (89.9 – 103) 3,493 Females 38.2 (37.1 – 39.3) 11.1 (10.3 – 12.9) 15.3 (14.2 – 16.4) 40.1 (38.9 – 41.6) 77.6 (75.1 – 80.5) 86.0 (81.9 – 92.1) 3,656 Race/ethnicity Mexican Americans 36.2 (35.3 – 37.1) 13.7 (11.8 – 14.3) 16.6 (15.3 – 17.9) 37.4 (36.1 – 38.9) 70.5 (67.0 – 74.0) 79.3 (74.1 – 91.3) 1,818 Non-Hispanic Blacks 41.3 (39.2 – 43.5) 12.9 (10.9 – 14.2) 16.7 (14.3 – 18.0) 43.1 (41.1 – 45.5) 86.4 (83.0 – 89.5) 97.2 (91.5 – 107) 1,846 Non-Hispanic Whites 39.6 (38.6 – 40.6) 10.9 (9.72 – 12.5) 15.1 (14.2 – 16.0) 42.4 (41.3 – 43.3) 81.1 (78.9 – 82.9) 89.7 (87.2 – 94.8) 2,943
6−11 12−19 20−39 40−59 60+ 

0 20 40 60 

Serum total lycopene (μg/dL) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

60

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.12.a. Serum total lycopene: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2005–2006 Serum total lycopene Serum total lycopene (μg/dL) (μg/dL) 0 20 40 60 0 20 40 

6−11 12−19 20−39 

Females 

40−59 60+ 6−11 12−19 20−39 

Males 

40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

6−11 12−19 

Age (years) 

20−39 40−59 60+ 6−11 12−19 

Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 167167
168 2nd 168 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.12.a.2. Serum total lycopene: Total population

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 39.4 (38.5 – 40.2) 20.5 (19.5 – 21.3) 41.8 (41.0 – 42.6) 71.2 (69.5 – 72.7) 7,149

6–11 years 39.7 (37.5 – 42.0) 21.5 (19.3 – 25.4) 40.9 (38.5 – 44.1) 67.6 (63.5 – 74.9) 851

12–19 years 39.5 (38.2 – 40.8) 23.5 (21.8 – 24.6) 40.6 (39.6 – 42.0) 66.3 (63.1 – 69.6) 1,907

20–39 years 43.8 (42.7 – 44.9) 24.6 (21.9 – 27.2) 45.2 (43.8 – 46.6) 74.0 (72.5 – 75.8) 1,667

40–59 years 40.5 (38.2 – 42.9) 21.0 (18.6 – 22.9) 43.1 (41.1 – 45.3) 72.8 (70.3 – 77.1) 1,346

60 years and older 31.5 (29.8 – 33.2) 14.3 (13.3 – 15.9) 33.5 (31.4 – 35.9) 62.8 (60.2 – 67.5) 1,378

Males

Total, 6 years and older 40.6 (39.3 – 42.0) 21.2 (20.1 – 22.2) 43.5 (42.2 – 44.7) 72.9 (70.9 – 75.6) 3,493

6–11 years 41.4 (39.2 – 43.8) 23.7 (20.3 – 26.4) 42.1 (39.7 – 44.9) 69.5 (63.4 – 78.2) 421

12–19 years 40.1 (38.5 – 41.8) 23.8 (21.3 – 26.0) 41.1 (40.0 – 42.5) 66.3 (64.6 – 69.4) 955

20–39 years 46.4 (44.5 – 48.5) 26.8 (22.9 – 30.6) 48.3 (45.5 – 51.0) 78.5 (74.6 – 81.9) 730

40–59 years 41.2 (37.7 – 45.0) 20.9 (15.2 – 23.9) 44.9 (42.6 – 47.1) 75.0 (71.0 – 81.4) 663

60 years and older 31.3 (29.1 – 33.7) 14.3 (12.6 – 15.9) 34.4 (31.6 – 36.4) 62.0 (59.0 – 69.3) 724

Females

Total, 6 years and older 38.2 (37.1 – 39.3) 19.9 (18.8 – 21.1) 40.1 (38.9 – 41.6) 69.3 (67.0 – 71.7) 3,656

6–11 years 37.9 (34.8 – 41.3) 19.4 (16.3 – 24.7) 39.8 (35.7 – 43.9) 66.2 (59.8 – 74.0) 430

12–19 years 38.8 (36.2 – 41.5) 23.4 (20.0 – 24.6) 40.1 (37.8 – 42.7) 65.3 (60.1 – 72.6) 952

20–39 years 41.3 (40.2 – 42.4) 22.6 (20.7 – 26.2) 42.7 (41.5 – 43.7) 71.6 (66.4 – 74.0) 937

40–59 years 39.8 (37.6 – 42.1) 20.9 (18.9 – 22.8) 41.1 (37.8 – 45.0) 71.3 (68.8 – 75.6) 683

60 years and older 31.6 (29.7 – 33.5) 14.2 (12.9 – 16.4) 33.0 (30.8 – 35.8) 64.6 (58.0 – 69.7) 654

Table 2.12.a.3. Serum total lycopene: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 36.2 (35.3 – 37.1) 20.5 (19.5 – 21.7) 37.4 (36.1 – 38.9) 61.5 (58.8 – 63.5) 1,818

6–11 years 35.5 (33.8 – 37.3) 21.0 (18.7 – 22.5) 35.5 (33.8 – 37.3) 58.4 (55.7 – 63.1) 292

12–19 years 35.7 (34.5 – 37.0) 21.8 (19.6 – 23.4) 37.4 (36.0 – 38.7) 58.5 (55.6 – 61.8) 639

20–39 years 38.8 (36.5 – 41.1) 22.7 (18.7 – 24.7) 41.0 (39.1 – 42.5) 63.8 (58.8 – 71.2) 441

40–59 years 34.8 (32.7 – 37.1) 19.6 (17.4 – 21.1) 35.1 (32.6 – 38.5) 60.7 (57.3 – 65.5) 240

60 years and older 29.9 (27.3 – 32.8) 14.7 (11.9 – 17.9) 30.1 (27.9 – 33.8) 54.7 (48.8 – 65.8) 206

Males

Total, 6 years and older 37.6 (36.3 – 39.0) 21.4 (19.9 – 23.0) 39.2 (36.9 – 40.8) 63.1 (59.5 – 68.0) 867

6–11 years 34.4 (32.6 – 36.4) 20.2 (17.8 – 22.4) 34.3 (31.7 – 36.1) 57.4 (50.5 – 73.4) 142

12–19 years 36.9 (34.6 – 39.4) 22.5 (19.2 – 24.6) 39.1 (36.8 – 40.7) 59.7 (55.9 – 63.9) 310

20–39 years 41.3 (37.8 – 45.1) 24.6 (16.6 – 27.7) 42.6 (40.6 – 45.6) 66.1 (58.3 – 94.4) 192

40–59 years 35.6 (32.6 – 38.8) 19.0 (14.4 – 22.6) 36.4 (33.4 – 40.5) 58.7 (56.0 – 74.3) 120

60 years and older 29.9 (25.1 – 35.7) 14.5† (5.80 – 18.2) 30.2 (26.0 – 36.1) 61.9† (48.0 – 86.3) 103

Females

Total, 6 years and older 34.8 (33.8 – 35.8) 20.0 (18.7 – 21.4) 35.3 (33.5 – 37.3) 59.5 (56.8 – 62.0) 951

6–11 years 36.7 (34.4 – 39.1) 21.1 (17.7 – 24.4) 36.7 (34.3 – 40.4) 58.8 (56.3 – 62.2) 150

12–19 years 34.5 (33.2 – 35.8) 20.6 (19.0 – 22.6) 34.8 (33.8 – 36.8) 57.8 (51.9 – 62.0) 329

20–39 years 35.9 (33.9 – 38.1) 20.2 (17.5 – 22.7) 37.4 (33.3 – 41.9) 61.4 (56.1 – 68.6) 249

40–59 years 34.0 (31.6 – 36.7) 19.6 (16.1 – 21.4) 33.0 (30.2 – 38.3) 61.0 (55.9 – 67.8) 120

60 years and older 29.9 (27.3 – 32.8) 16.1† (12.1 – 20.5) 29.2 (26.6 – 35.7) 52.7† (48.0 – 59.9) 103

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 169169

Table 2.12.a.4. Serum total lycopene: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 41.3 (39.2 – 43.5) 21.4 (19.5 – 23.1) 43.1 (41.1 – 45.5) 75.5 (72.1 – 79.6) 1,846

6–11 years 47.9 (43.3 – 52.9) 27.4 (20.5 – 31.8) 49.6 (44.6 – 56.3) 78.5 (73.9 – 84.4) 236

12–19 years 44.3 (42.3 – 46.4) 26.9 (23.9 – 29.0) 45.8 (42.8 – 47.8) 73.1 (69.2 – 78.2) 636

20–39 years 47.0 (44.2 – 50.1) 26.4 (23.2 – 29.6) 49.0 (45.5 – 52.3) 79.6 (76.1 – 82.9) 363

40–59 years 39.2 (36.4 – 42.2) 20.0 (17.1 – 21.4) 40.8 (37.7 – 43.4) 73.7 (66.9 – 84.2) 331

60 years and older 28.2 (26.0 – 30.6) 12.7 (10.4 – 15.4) 29.1 (26.6 – 32.7) 59.0 (53.0 – 68.4) 280

Males

Total, 6 years and older 43.6 (41.0 – 46.3) 22.9 (19.5 – 24.5) 45.8 (42.8 – 48.4) 81.2 (76.4 – 87.8) 922

6–11 years 49.5 (44.4 – 55.1) 30.6 (15.3 – 35.9) 50.4 (42.4 – 58.7) 76.8 (70.9 – 91.8) 126

12–19 years 45.7 (43.1 – 48.6) 28.9 (25.6 – 30.2) 46.7 (43.6 – 50.4) 76.3 (69.3 – 90.2) 324

20–39 years 51.6 (48.4 – 55.1) 29.7 (25.9 – 31.9) 51.4 (48.1 – 54.9) 86.3 (81.2 – 90.5) 169

40–59 years 40.0 (35.3 – 45.3) 18.4 (13.2 – 22.9) 41.1 (36.8 – 47.4) 82.9 (67.2 – 97.5) 153

60 years and older 28.9 (26.5 – 31.6) 12.5 (11.1 – 13.0) 31.1 (28.3 – 34.7) 59.5 (52.9 – 66.0) 150

Females

Total, 6 years and older 39.3 (37.0 – 41.8) 20.8 (18.5 – 22.2) 41.0 (39.4 – 43.0) 71.4 (68.7 – 74.1) 924

6–11 years 46.3 (41.2 – 52.1) 24.6† (17.9 – 27.5) 48.5 (44.6 – 54.8) 78.5† (72.8 – 84.6) 110

12–19 years 42.9 (39.5 – 46.4) 25.6 (20.1 – 28.1) 44.1 (39.8 – 48.0) 70.4 (67.3 – 75.3) 312

20–39 years 43.4 (39.8 – 47.3) 23.6 (21.0 – 28.0) 44.5 (40.4 – 50.6) 72.6 (68.4 – 76.7) 194

40–59 years 38.6 (36.3 – 41.0) 20.1 (17.1 – 21.5) 40.2 (36.7 – 43.0) 68.6 (63.6 – 75.8) 178

60 years and older 27.7 (24.1 – 31.9) 12.8 (8.09 – 17.2) 28.6 (24.8 – 32.4) 57.6 (45.4 – 82.2) 130

† Estimate is subject to greater uncertainty due to small cell size.

Table 2.12.a.5. Serum total lycopene: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in μg/dL) for non-Hispanic whites in the 

U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2005–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 39.6 (38.6 – 40.6) 20.4 (19.4 – 21.3) 42.4 (41.3 – 43.3) 71.5 (69.4 – 73.8) 2,943

6–11 years 39.3 (35.9 – 43.1) 20.7 (18.9 – 24.9) 40.6 (37.7 – 44.9) 64.8 (58.7 – 78.0) 230

12–19 years 39.2 (37.5 – 40.9) 23.3 (20.8 – 24.8) 40.7 (39.3 – 42.1) 66.2 (62.8 – 70.2) 489

20–39 years 44.8 (43.2 – 46.5) 25.3 (21.5 – 29.3) 45.9 (44.0 – 48.4) 75.4 (72.5 – 77.8) 706

40–59 years 41.6 (38.8 – 44.6) 22.2 (17.8 – 24.4) 44.7 (42.6 – 47.0) 73.9 (70.4 – 78.5) 674

60 years and older 31.7 (30.0 – 33.5) 14.4 (13.3 – 16.2) 33.9 (31.7 – 36.7) 62.9 (60.2 – 67.4) 844

Males

Total, 6 years and older 40.7 (39.2 – 42.3) 21.0 (19.7 – 22.0) 43.9 (42.5 – 45.2) 73.2 (70.9 – 76.0) 1,461

6–11 years 41.5 (38.1 – 45.3) 23.6† (19.7 – 26.4) 42.3 (39.5 – 45.7) 66.0† (58.8 – 81.5) 111

12–19 years 39.8 (37.1 – 42.6) 23.2 (19.9 – 27.0) 41.0 (38.4 – 43.0) 66.3 (63.5 – 69.8) 251

20–39 years 47.2 (44.7 – 49.8) 26.8 (21.7 – 31.6) 49.4 (45.9 – 52.3) 78.7 (73.9 – 85.0) 308

40–59 years 42.6 (38.4 – 47.1) 22.4 (15.0 – 27.3) 46.3 (44.0 – 49.0) 75.3 (70.9 – 82.7) 346

60 years and older 31.2 (28.6 – 34.0) 14.4 (12.3 – 16.1) 33.9 (30.8 – 36.5) 62.0 (58.8 – 69.7) 445

Females

Total, 6 years and older 38.5 (36.9 – 40.1) 19.7 (18.2 – 21.3) 40.7 (38.9 – 42.5) 69.6 (66.8 – 72.6) 1,482

6–11 years 37.0 (32.7 – 41.8) 19.1 (13.7 – 25.3) 39.1 (33.8 – 43.3) 61.9 (54.6 – 78.0) 119

12–19 years 38.6 (35.1 – 42.3) 23.6 (18.0 – 25.6) 40.4 (37.0 – 43.4) 64.4 (57.9 – 75.6) 238

20–39 years 42.5 (40.6 – 44.4) 22.9 (19.9 – 28.7) 43.2 (41.9 – 44.2) 72.1 (66.5 – 77.0) 398

40–59 years 40.7 (37.6 – 44.0) 21.6 (17.5 – 24.5) 42.4 (39.0 – 47.4) 72.1 (68.7 – 78.7) 328

60 years and older 32.2 (30.3 – 34.2) 14.3 (12.9 – 16.6) 33.8 (31.6 – 37.1) 64.5 (59.0 – 68.7) 399

† Estimate is subject to greater uncertainty due to small cell size.
170 2nd 170 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

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Vitamin D

Background Information

Sources and Physiological Functions. Vitamin D (calciferol) comprises a group of fat soluble

seco-sterols found naturally in only a few foods, such as fish-liver oils, fatty fishes, mushrooms, egg

yolks, and liver. The two major physiologically relevant forms of vitamin D are D2 (ergocalciferol)

and D3 (cholecalciferol). Vitamin D3 is photosynthesized in the skin of vertebrates by the action

of solar ultraviolet (UV) B radiation on 7-dehydrocholesterol present in the skin (Fieser 1959).

Vitamin D2 is produced by UV irradiation of ergosterol, which occurs in molds, yeast, and higherorder plants. Under conditions of regular sun exposure, dietary vitamin D intake is of minor

importance. However, latitude, season, aging, sunscreen use, and skin pigmentation influence the

production of vitamin D3 by the skin (Institute of Medicine 2011). In the United States, most

of the dietary intake of vitamin D comes from fortified milk products and other fortified foods

such as breakfast cereals and orange juice (Institute of Medicine 2011). Both vitamin D2 and D3

are used in nonprescription vitamin D supplements, but vitamin D2 is the only form available by

prescription in the United States (Holick 2007).

Vitamin D without a subscript represents either D2 or D3 or both. Vitamin D, per se, is

biologically inert. Whether derived from the skin or diet, vitamin D is only short-lived in

circulation (with a half-life of 1–2 days), as it is either stored in fat cells or metabolized in the liver

(Mawer 1972). In circulation, vitamin D is bound to vitamin D-binding protein and transported

to the liver, where it is converted to 25-hydroxyvitamin D [25(OH)D] (DeLuca 1984). This

major circulating form of vitamin D is a good reflection of cumulative effects of exposure

to sunlight and dietary intake of vitamin D (Haddad 1973; Holick 1995) and is therefore

used by clinicians to determine vitamin D status. To be biologically activated at physiologic

concentrations, 25(OH)D must be converted in the kidneys to 1,25-dihydroxyvitamin D

[1,25(OH)2D], which is thought to be responsible for most, if not all, of the biologic functions

of vitamin D (DeLuca 1988; Reichel 1989). The production of 25(OH)D in the liver is a

function of vitamin D availability from dietary intake and sun exposure whereas production of

1,25(OH)2D in the kidney is tightly regulated by mineral requirements. In the liver, vitamin

D-25-hydroxylase is down-regulated by vitamin D and its metabolites, thereby limiting any

increase in the circulating concentration of 25(OH)D following intakes or following production

of vitamin D after exposure to sunlight. In the kidney, in response to serum calcium and

phosphorus concentrations, the production of 1,25(OH)2D is regulated through the action of

parathyroid hormone (PTH) (DeLuca 1988; Reichel 1989).

Health Effects. Active vitamin D (1,25-dihydroxyvitamin D) functions as a hormone, and its

main biologic function in people is to maintain serum calcium and phosphorus concentrations

within the normal range by enhancing the efficiency of the small intestine to absorb these

minerals from the diet (DeLuca 1988; Reichel 1989). When dietary calcium intake is inadequate

to satisfy the body’s calcium requirement, 1,25(OH)2D, along with PTH, mobilizes calcium

stores from the bone. In the kidney, 1,25(OH)2D increases calcium reabsorption by the distal

renal tubules. Apart from these traditional calcium-related actions, 1,25(OH)2D and its synthetic

analogs are increasingly recognized for their potent anti-proliferative, pro-differentiative, and

immunomodulatory activities (Nagpal 2005).

Vitamin D deficiency is characterized by inadequate mineralization or by demineralization of

the skeleton. Among children, vitamin D deficiency is a common cause of bone deformities

known as rickets. Vitamin D deficiency in adults leads to a mineralization defect in the skeleton,
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 173173

causing osteomalacia, and it induces secondary hyperparathyroidism with consequent bone loss

and osteoporosis. Potential roles for vitamin D beyond bone health, such as effects on muscle

strength, the risk for cancer, and the risk for type 2 diabetes, are under intense investigation. The

Agency for Healthcare Research and Quality (AHRQ) reviewed the effectiveness and safety of

vitamin D on outcomes related to bone health (Cranney 2007). The report suggests that vitamin

D supplementation has positive effects on bone health in postmenopausal women and older men.

Another AHRQ systematic review of vitamin D status and health outcomes found no significant

associations between vitamin D status and total cancer mortality, nor did it find any conclusive

evidence for the association of vitamin D status with cancer risk or cancer outcome (Chung

2009). It also found no clear association between vitamin D status and cardiometabolic outcomes

including fasting glucose, blood pressure, myocardial infarction or stroke. Randomized trials

showed no clinically significant consistent effects of vitamin D supplementation at the dosages

given (Pittas 2010).

Intake Recommendations. What constitutes the optimal intake of vitamin D remains a matter

of some disagreement. Current recommendations from the Institute of Medicine (2011) call for

400 international units (IU) [10 micrograms (μg)] of vitamin D daily from birth through age

1 year for adequate intake (AI)]. The Recommended Dietary Allowance (RDA) for those aged

1–70 years is 600 IU (15 μg) and 800 IU (20 μg) for those older than 70 years. According to

the Dietary Guidelines for Americans (U.S. Department of Agriculture and U.S. Department of

Health Human Services 2010), moderate evidence shows that intake of milk and milk products is

linked to improved bone health, especially in children and adolescents. In the United States, most

dietary vitamin D is obtained from fortified foods, especially milk. The Tolerable Upper Intake

Level for vitamin D is 4000 IU (100 μg) per day in North America for individuals 9 years of age

and older and ranges from 1000 IU to 3000 IU for infants and children less than 9 years of age; as

intake increases above this amount, the potential risk for adverse consequences increases.

Biochemical Indicators and Methods. To assess vitamin D status, one measures the

concentration of 25(OH)D in serum, using either antibody-based methods such as radioisotope-,

enzyme-linked- or chemiluminescence- immunoassays, or using chemistry-based methods such

as HPLC separation with UV or tandem mass spectrometry detection. Studies have shown that

standardized chemistry-based methods are equivalent but that antibody-based methods may show

significant bias. Some clinical laboratories use conventional units for 25(OH)D (nanogram per

milliliter [ng/mL]), whereas other laboratories use

international system (SI) units (nanomole per liter

[nmol/L]). The conversion factor to SI units is:

1 ng/mL = 2.5 nmol/L.

The Institute of Medicine (2011) committee to

review dietary reference intakes for vitamin D and

calcium suggested that persons with serum 25(OH)

D concentrations of less than 30 nmol/L (12 ng/mL)

are at risk for deficiency; those with concentrations

of at least 30 but less than 50 nmol/L (12 to less

than 20 ng/mL) are at risk for inadequacy; and those

with concentrations between 50–75 nmol/L (20–30

ng/mL) are considered sufficient. The Committee

indicated that concentrations greater than 125 nmol/L

(50 ng/mL) may be reason for concern. Of interest
174 2nd 174 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

to public health scientists, the report indicated that a serum 25(OH)D level consistent with the

Estimated Average Requirement for dietary intake (EAR) lies between 30 and 50 nmol/L and that

40 nmol/L was selected from the middle of the range to serve as the targeted level for median dietary

requirements (Institute of Medicine 2011).

A number of external quality assurance programs exist for serum or plasma 25(OH)D

concentration measurements, including those sponsored by DEQAS (Vitamin D External

Quality Assessment Scheme), College of American Pathologists (Bone and Growth Survey and

Accuracy-Based Vitamin D Survey), and NIST/NIH (Vitamin D Metabolites Quality Assurance

Program). Standard reference materials (SRM 972) with certified values for 25(OH)D2, 25(OH)

D3 and C3-epimer of 25(OH)D3 are available from the U.S. National Institute of Standards and

Technology (NIST). An additional solvent-based reference material set (SRM 2972) with certified

values for 25(OH)D2 and 25(OH)D3 is also available (https://www-s.nist.gov/srmors/view_detail.

cfm?srm=972). Further improvement in the agreement between laboratories and methods is

expected as more laboratories use these SRMs.

Data in NHANES. The data in this report were obtained by use of an antibody-based method,

specifically a radioimmunoassay (DiaSorin, Stillwater, MN). The manufacturer reformulated the

kit in the late 1990s, resulting in data that were on average 12% lower than those generated with

the original kit. To make NHANES III data (original kit) comparable to data from 2001–2006

(reformulated kit), we followed the recommendations of a panel of experts (Yetley 2010) to use

a published adjustment equation for the NHANES III data (see Analytic Note at http://www.

cdc.gov/nchs/nhanes/nhanes2005-2006/VID_D.htm). The Analytic Note also reported that

the reformulated kit showed some assay drifts between 2001 and 2006. To generate 2003–2004

and 2005–2006 tables and figures, we used the public release data files from November 2010.

Using data that were already adjusted for these assay drifts was the most appropriate way to make

comparisons across survey cycles.

Since 1988, NHANES has monitored the vitamin D status of the U.S. population. By design,

this survey collects information and biological samples in the summer from people living at higher

latitudes and in the winter from people living at lower latitudes. Because the different racial and

ethnic groups are not evenly distributed across all geographic regions in the United States, the

season-latitude structure of the survey can affect comparisons by race or ethnicity. In two seasonal

subpopulations from NHANES III (1988–1994), Looker et al. (2002) showed that in the winter

and lower latitude subpopulation, 1–5% and 25–57% had 25(OH)D concentrations less than

25 nmol/L (10 ng/mL) and less than 62.5 nmol/L (25 ng/mL), respectively. In the summer and

higher latitude subpopulation, 1–3% and 21–49% had 25(OH)D concentrations below these

cutoffs. Mean 25(OH)D concentrations were highest in non-Hispanic whites, intermediate in

Mexican Americans, and lowest in non-Hispanic blacks. A more recent analysis of NHANES

III and NHANES 2000–2004 (Looker 2008) demonstrated that overall, mean serum 25(OH)

D were 5–9 nmol/L lower in 2000–2004 than in 1988–1994 in most males, but not in most

females. Factors related to changes in vitamin D status were increased body mass index, decreased

milk intake, and increased usage of sun protection in the more recent surveys.

For more information about vitamin D, see the Institute of Medicine’s Dietary Reference Intake

reports (Institute of Medicine 2011), fact sheets from the National Institutes of Health, Office of

Dietary Supplements

(http://ods.od.nih.gov/Health_Information/Information_About_Individual_Dietary_

Supplements.aspx).
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 175175

Highlights

Serum 25-hydroxyvitamin D [25(OH)D] concentrations in the U.S. population showed the

following demographic patterns and characteristics:

•	 Concentrations generally decreased with increasing age.

•	 No consistent pattern was observed with regard to gender.

•	 Among the three race/ethnic groups, non-Hispanic blacks had the lowest 25(OH)D

concentrations and non-Hispanic whites had the highest concentrations.

•	 The likelihood of being vitamin D deficient was significantly influenced by race/

ethnicity.

During the past several years, the vitamin D status of the U.S. population was under intensive

investigation to determine whether a downward trend was apparent. In the analysis below, we

used data that were adjusted for radioimmunoassay reformulation and assay drifts according to

recommendations made by a panel of experts (Yetley 2010). The age-adjusted mean 25(OH)D

concentrations in the U.S. population decreased by approximately 10% between NHANES III

and the periods 2001–2002 and 2003–2006 (Figure H.2.b). Decreases were seen in all groups

shown (total or stratified by gender or race/ethnicity). Similarly, a recent report found that the

age- and season-adjusted prevalence at risk of deficiency (serum 25(OH)D concentrations less

than 30 nmol/L) increased between 1988–1994 and 2001–2002 from 4% to 7% for males aged

12 years and older and from 7% to 11% for females aged 12 years and older (Looker 2011).

Figure H.2.b. Age-adjusted geometric mean concentrations of serum 25-hydroxyvitamin D in the U.S. population aged 12 years and

older by gender or race/ethnicity, National Health and Nutrition Examination Survey, 1988–2006.

Error bars represent 95% confidence intervals. Within a demographic group, bars not sharing a common letter differ (p < 0.05). Age adjustment was

done using direct standardization.

It is interesting to note that non-Hispanic blacks one year and older had the highest prevalence

of vitamin D deficiency (serum 25(OH)D concentrations less than 30 nmol/L) (Figure H.2.c),

despite clinical data showing superior bone health with greater density and fewer fractures than

other race/ethnic groups; further research is needed to explain this unusual finding (Aloia 2008).

Higher peak bone mass, higher obesity rates, greater muscle mass and lower bone turnover

are some of the factors that have been suggested to protect African Americans against fracture

a 

a 

a 

a 

a 

a 

b b 

b 

b 

b 

b 

b b b 

b 

c 

b 

0 

10 

20 

30 

40 

50 

60 

70 

80 

Total 

population 

Males Females Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Serum 25-hydroxyvitamin D (nmol/L) 

1988-1994 2001-2002 2003-2006 
176 2nd 176 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

(Aloia 2008). Non-Hispanic blacks and Mexican Americans had the highest prevalence of low

serum 25(OH)D concentrations categorized at risk for inadequacy (30 to less than 50 nmol/L)

compared to non-Hispanic whites (Figure H.2.c).

Figure H.2.c. Age-adjusted prevalence estimates of serum 25-hydroxyvitamin D concentrations less than 30 and 30 to less than 50

nmol/L in the U.S. population aged 1 year and older by race/ethnicity, National Health and Nutrition Examination Survey, 2003–

2006.

Error bars represent 95% confidence intervals. Within each vitamin D status category, bars not sharing a common letter differ (p < 0.05). Age

adjustment was done using direct standardization.

The Institute of Medicine (2011) report concluded that serum 25(OH)D levels of 40 nmol/L

are at a level consistent with a desirable median intake of vitamin D. Non-Hispanic blacks had

significantly higher prevalence of serum concentrations less than 40 nmol/L (Figure H.2.d) which

corresponds to the targeted level for the median dietary requirement. The median meets the

requirement of approximately half the population thus individuals with concentrations less than

40 nmol/L are at increased risk of adverse health outcomes.

Figure H.2.d. Age-adjusted prevalence estimates of serum 25-hydroxyvitamin D concentrations less than 40 nmol/L in the U.S.

population aged 1 years and older by race/ethnicity, National Health and Nutrition Examination Survey, 2003–2006.

Error bars represent 95% confidence intervals. Bars not sharing a common letter differ (p < 0.05). Age adjustment was done using direct

standardization.

a 

b 

c 

a 

b 

c 

0 

5 

10 

15 

20 

25 

30 

35 

40 

45 

Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Prevalence (%) 

< 30 nmol/L 30 to < 50 nmol/L 

a 

b 

c 

0 

10 

20 

30 

40 

50 

60 

70 

Prevalence (%) 

Mexican American Non-Hispanic black 

< 40 nmol/L

Non-Hispanic white 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 177177

Detailed Observations

The selected observations mentioned below are derived from the tables and figures presented next.

Statements about categorical differences between demographic groups noted below are based on

non-overlapping confidence limits from univariate analysis without adjusting for demographic

variables (e.g., age, gender, race/ethnicity) or other blood concentration determinants (e.g., dietary

intake, supplement usage, smoking, BMI). A multivariate analysis may alter the size and statistical

significance of these categorical differences. Furthermore, additional significant differences of

smaller magnitude may be present despite their lack of mention here (e.g., if confidence limits

slightly overlap or if differences are not statistically significant before covariate adjustment has

occurred). For a selection of citations of descriptive NHANES papers related to these biochemical

indicators of diet and nutrition, see Appendix G.

Geometric mean concentrations (NHANES 2003–2006):

•	 Serum 25(OH)D concentrations decreased through adolescence and then stabilized

(Table 2.13.a.1).

•	 Non-Hispanic blacks had the lowest concentrations of serum 25(OH)D (Table

2.13.a.1).

Changes in geometric mean concentrations across surveys:

•	 Geometric mean 25(OH)D concentrations remained steady across the survey cycles

from 2001–2006 (Table 2.13.b).

Prevalence estimates of low or high biochemical indicator concentrations:

•	 Between 2003 and 2006, 8% of the population aged 1 year and older were at risk for

vitamin D deficiency, as defined by a serum concentration < 30 nmol/L, whereas 24%

had serum concentrations between 30 and less than 50 nmol/L, levels that placed

them at risk for inadequacy (Tables 2.13.c.1 and 2.13.c.2). Approximately 17% of the

population had concentrations < 40 nmol/L which is considered the level associated

with desirable intake (Tables 2.13.c.3). Less than 1% had serum concentrations > 125

nmol/L, a level that may be reason for concern about excess (Tables 2.13.c.4).

•	 Less than 2% of children (1–11 years) were at risk for vitamin D deficiency (Table

2.13.c.1).

•	 More females (10%) than males (6%) were at risk for vitamin D deficiency (Table

2.13.c.1).

•	 More non-Hispanic blacks (31%) were at risk for vitamin D deficiency than nonHispanic whites (4%) or Mexican Americans (11%) (Table 2.13.c.1).

•	 The prevalence of risk for vitamin D deficiency remained steady across the 2001–2006

survey cycles (Table 2.13.d.1).
178

2nd 178 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.13.a.1. Serum 25-hydroxyvitamin D: Concentrations Geometric mean and selected percentiles of serum concentrations (in nmol/L) for the total U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 1 year and older 55.6 (53.6 – 57.6) 18.5 (17.4 – 19.7) 23.2 (21.4 – 25.0) 58.0 (56.3 – 59.9) 96.6 (93.9 – 101) 108 (105 – 112) 16,604 Age group 1–5 years 68.6 (66.7 – 70.5) 36.9 (32.9 – 38.8) 41.6 (39.5 – 43.4) 68.8 (66.9 – 70.6) 99.6 (95.7 – 107) 107 (102 – 121) 1,799 6–11 years 63.8 (61.6 – 66.1) 30.5 (27.3 – 31.6) 35.3 (32.0 – 38.7) 64.5 (63.0 – 66.1) 97.2 (92.5 – 108) 105 (98.4 – 122) 1,768 12–19 years 55.1 (52.4 – 58.0) 18.0 (15.6 – 20.1) 22.7 (19.8 – 25.1) 57.6 (55.3 – 60.1) 98.4 (94.3 – 108) 111 (106 – 123) 4,044 20–39 years 54.5 (52.1 – 57.0) 17.6 (15.9 – 19.0) 21.8 (20.3 – 23.3) 56.6 (54.4 – 58.9) 102 (97.2 – 108) 115 (110 – 122) 3,262 40–59 years 53.6 (51.3 – 56.0) 17.8 (16.3 – 18.9) 21.7 (19.8 – 23.6) 56.0 (54.1 – 58.1) 94.3 (90.5 – 98.3) 103 (98.0 – 110) 2,660 60 years and older 54.1 (52.4 – 55.8) 19.1 (18.1 – 20.1) 23.1 (21.6 – 24.6) 56.9 (55.4 – 58.5) 91.9 (89.5 – 95.0) 100 (96.6 – 106) 3,071 Gender Males 56.7 (54.7 – 58.7) 20.7 (18.6 – 22.3) 25.8 (23.8 – 27.3) 58.9 (57.1 – 60.7) 94.0 (90.7 – 97.7) 103 (98.6 – 109) 8,145 Females 54.5 (52.5 – 56.6) 17.6 (16.2 – 18.5) 21.2 (19.8 – 22.5) 57.2 (55.2 – 59.2) 99.4 (96.1 – 106) 112 (108 – 117) 8,459 Race/ethnicity Mexican Americans 48.7 (46.3 – 51.2) 18.2 (16.8 – 19.4) 21.5 (19.6 – 23.3) 49.9 (47.7 – 53.4) 81.8 (79.2 – 84.7) 88.2 (85.4 – 92.0) 4,275 Non-Hispanic Blacks 36.1 (34.3 – 38.0) 12.0 (11.0 – 12.8) 14.3 (13.5 – 15.1) 36.6 (34.2 – 39.1) 70.9 (68.5 – 73.7) 79.0 (74.9 – 82.2) 4,349 Non-Hispanic Whites 61.9 (60.3 – 63.4) 24.9 (23.3 – 25.9) 31.0 (29.1 – 32.6) 63.2 (61.8 – 64.6) 102 (97.8 – 106) 113 (110 – 117) 6,698
1−5 6−11 12−19 20−39 40−59 60+ 

0 20 40 60 80 

Serum 25−hydroxyvitamin D (nmol/L) 

Overall 

1−5 6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

80

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.13.a. Serum 25−hydroxyvitamin D: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Serum 25−hydroxyvitamin D Serum 25−hydroxyvitamin D (nmol/L) (nmol/L) 0 20 40 60 80 0 20 40 60 

1−5 6−11 12−19 20−39 40−59 60+ 1−5 6−11 12−19 20−39 40−59 60+ 

Females Males 

1−5 6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

1−5 6−11 12−19 20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 179179
180 2nd 180 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.13.a.2. Serum 25-hydroxyvitamin D: Total population

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for the total U.S. population 

aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 55.6 (53.6 – 57.6) 23.2 (21.4 – 25.0) 58.0 (56.3 – 59.9) 96.6 (93.9 – 101) 16,604

1–5 years 68.6 (66.7 – 70.5) 41.6 (39.5 – 43.4) 68.8 (66.9 – 70.6) 99.6 (95.7 – 107) 1,799

6–11 years 63.8 (61.6 – 66.1) 35.3 (32.0 – 38.7) 64.5 (63.0 – 66.1) 97.2 (92.5 – 108) 1,768

12–19 years 55.1 (52.4 – 58.0) 22.7 (19.8 – 25.1) 57.6 (55.3 – 60.1) 98.4 (94.3 – 108) 4,044

20–39 years 54.5 (52.1 – 57.0) 21.8 (20.3 – 23.3) 56.6 (54.4 – 58.9) 102 (97.2 – 108) 3,262

40–59 years 53.6 (51.3 – 56.0) 21.7 (19.8 – 23.6) 56.0 (54.1 – 58.1) 94.3 (90.5 – 98.3) 2,660

60 years and older 54.1 (52.4 – 55.8) 23.1 (21.6 – 24.6) 56.9 (55.4 – 58.5) 91.9 (89.5 – 95.0) 3,071

Males

Total, 1 year and older 56.7 (54.7 – 58.7) 25.8 (23.8 – 27.3) 58.9 (57.1 – 60.7) 94.0 (90.7 – 97.7) 8,145

1–5 years 69.2 (67.0 – 71.5) 41.7 (40.1 – 43.5) 69.3 (66.7 – 71.6) 101 (96.7 – 106) 904

6–11 years 65.5 (63.2 – 67.9) 36.9 (32.5 – 40.3) 65.8 (64.3 – 67.6) 98.0 (92.4 – 116) 862

12–19 years 56.6 (54.0 – 59.3) 25.3 (22.5 – 28.0) 58.7 (56.4 – 61.2) 95.2 (88.8 – 105) 2,049

20–39 years 53.7 (51.4 – 56.1) 23.6 (20.9 – 25.7) 55.9 (53.7 – 57.8) 90.6 (87.7 – 96.7) 1,472

40–59 years 55.8 (53.3 – 58.4) 25.3 (22.4 – 27.0) 58.0 (55.8 – 60.8) 92.4 (88.1 – 98.7) 1,311

60 years and older 55.6 (53.7 – 57.7) 26.0 (23.8 – 27.9) 57.5 (55.6 – 59.7) 91.9 (89.1 – 97.2) 1,547

Females

Total, 1 year and older 54.5 (52.5 – 56.6) 21.2 (19.8 – 22.5) 57.2 (55.2 – 59.2) 99.4 (96.1 – 106) 8,459

1–5 years 67.9 (65.8 – 70.0) 41.3 (37.4 – 44.3) 68.4 (66.3 – 70.3) 98.1 (93.3 – 113) 895

6–11 years 61.9 (59.6 – 64.4) 34.0 (31.4 – 37.6) 62.8 (60.1 – 65.3) 96.4 (92.5 – 103) 906

12–19 years 53.6 (50.6 – 56.9) 20.6 (18.0 – 22.9) 56.4 (53.1 – 59.5) 106 (96.5 – 114) 1,995

20–39 years 55.3 (52.4 – 58.3) 20.5 (19.1 – 21.8) 57.6 (54.4 – 60.7) 110 (106 – 116) 1,790

40–59 years 51.6 (49.2 – 54.2) 19.4 (18.3 – 20.6) 54.1 (50.8 – 57.0) 95.1 (91.5 – 99.2) 1,349

60 years and older 52.9 (51.1 – 54.7) 21.7 (20.2 – 23.2) 56.4 (54.5 – 58.2) 92.0 (89.1 – 95.8) 1,524

Table 2.13.a.3. Serum 25-hydroxyvitamin D: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for Mexican Americans in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 48.7 (46.3 – 51.2) 21.5 (19.6 – 23.3) 49.9 (47.7 – 53.4) 81.8 (79.2 – 84.7) 4,275

1–5 years 64.8 (63.1 – 66.6) 42.5 (39.4 – 44.7) 64.3 (62.3 – 66.1) 93.8 (89.5 – 99.7) 584

6–11 years 56.9 (55.0 – 58.8) 32.7 (30.9 – 34.9) 58.2 (56.3 – 59.8) 82.9 (80.7 – 86.9) 589

12–19 years 46.8 (44.2 – 49.6) 22.0 (20.2 – 23.4) 47.8 (45.6 – 50.7) 74.8 (71.2 – 83.6) 1,288

20–39 years 46.6 (43.6 – 49.7) 20.6 (17.6 – 23.5) 48.0 (45.4 – 51.5) 78.0 (75.6 – 83.1) 789

40–59 years 44.4 (41.4 – 47.7) 19.4 (17.4 – 21.2) 45.8 (41.9 – 49.0) 79.8 (72.4 – 87.7) 472

60 years and older 45.0 (42.4 – 47.8) 20.1 (17.6 – 21.4) 45.9 (43.6 – 48.1) 79.5 (73.4 – 89.5) 553

Males

Total, 1 year and older 51.1 (48.7 – 53.7) 24.5 (21.7 – 26.6) 52.7 (49.4 – 55.5) 81.7 (79.0 – 85.2) 2,073

1–5 years 65.2 (63.9 – 66.5) 44.6 (40.5 – 45.8) 64.4 (63.1 – 65.6) 94.9 (88.6 – 109) 282

6–11 years 58.8 (56.8 – 60.8) 36.0 (32.3 – 38.8) 59.7 (57.8 – 62.3) 83.3 (80.5 – 92.2) 286

12–19 years 49.5 (46.6 – 52.6) 23.8 (21.5 – 26.2) 50.0 (47.4 – 54.0) 78.0 (72.7 – 85.8) 641

20–39 years 49.1 (45.5 – 52.8) 24.3 (19.7 – 26.2) 49.8 (47.1 – 54.1) 77.0 (73.1 – 86.5) 353

40–59 years 47.4 (44.0 – 51.0) 20.9 (15.3 – 25.9) 47.4 (44.6 – 54.3) 79.8 (72.2 – 92.8) 239

60 years and older 48.0 (44.0 – 52.2) 21.4 (18.3 – 25.0) 48.3 (43.6 – 54.3) 81.2 (74.4 – 96.7) 272

Females

Total, 1 year and older 46.2 (43.7 – 48.8) 19.8 (18.9 – 20.6) 47.7 (45.4 – 50.3) 82.1 (78.6 – 85.4) 2,202

1–5 years 64.5 (61.8 – 67.2) 40.5 (36.0 – 44.3) 64.2 (59.9 – 67.5) 92.9 (89.1 – 98.6) 302

6–11 years 54.8 (52.3 – 57.5) 31.1 (25.0 – 33.7) 56.6 (54.0 – 58.8) 82.3 (74.5 – 93.8) 303

12–19 years 44.1 (41.4 – 47.1) 20.4 (17.3 – 22.5) 45.6 (42.4 – 48.0) 73.2 (67.7 – 80.3) 647

20–39 years 43.9 (40.7 – 47.3) 18.5 (16.4 – 20.4) 44.9 (41.6 – 48.2) 80.2 (74.8 – 87.1) 436

40–59 years 41.5 (37.9 – 45.3) 18.7 (17.5 – 20.0) 42.8 (37.3 – 46.8) 79.6 (70.9 – 85.0) 233

60 years and older 42.7 (39.6 – 46.1) 19.1 (15.4 – 21.1) 44.3 (40.5 – 47.0) 78.0 (71.5 – 88.9) 281
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 181181

Table 2.13.a.4. Serum 25-hydroxyvitamin D: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for non-Hispanic blacks in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 36.1 (34.3 – 38.0) 14.3 (13.5 – 15.1) 36.6 (34.2 – 39.1) 70.9 (68.5 – 73.7) 4,349

1–5 years 55.5 (52.7 – 58.5) 29.4 (21.0 – 33.4) 57.5 (54.5 – 59.6) 86.6 (82.1 – 91.3) 503

6–11 years 48.1 (45.7 – 50.6) 24.8 (23.4 – 25.7) 49.4 (47.3 – 52.2) 73.8 (71.5 – 80.2) 561

12–19 years 34.2 (31.4 – 37.2) 13.8 (13.0 – 14.6) 34.6 (31.3 – 38.2) 68.3 (64.2 – 72.2) 1,421

20–39 years 32.5 (30.4 – 34.8) 13.7 (12.7 – 14.8) 31.5 (29.2 – 34.2) 64.0 (61.1 – 70.4) 716

40–59 years 34.1 (32.0 – 36.3) 13.3 (11.6 – 14.8) 34.7 (32.4 – 37.7) 66.2 (62.0 – 71.6) 626

60 years and older 36.2 (34.1 – 38.3) 15.0 (13.2 – 15.9) 36.3 (33.8 – 39.7) 72.9 (67.6 – 80.3) 522

Males

Total, 1 year and older 38.0 (35.9 – 40.3) 15.5 (14.0 – 16.6) 38.6 (35.9 – 41.4) 71.8 (69.0 – 78.6) 2,166

1–5 years 56.5 (52.5 – 60.7) 30.0 (21.7 – 34.0) 58.4 (54.3 – 61.6) 89.1 (81.9 – 98.4) 248

6–11 years 51.0 (48.1 – 54.1) 26.0 (23.0 – 28.4) 53.0 (49.3 – 56.5) 75.0 (70.5 – 88.7) 277

12–19 years 36.9 (34.0 – 40.0) 14.6 (13.2 – 15.9) 38.1 (34.9 – 41.0) 70.8 (66.6 – 75.9) 745

20–39 years 32.4 (29.8 – 35.1) 13.8 (11.6 – 15.2) 30.5 (28.4 – 33.3) 64.9 (59.0 – 82.3) 339

40–59 years 37.4 (34.8 – 40.2) 15.9 (14.0 – 17.1) 38.2 (34.2 – 42.2) 69.6 (62.4 – 77.2) 293

60 years and older 37.5 (34.9 – 40.3) 15.0 (12.8 – 16.6) 38.5 (34.7 – 42.7) 72.3 (66.1 – 79.2) 264

Females

Total, 1 year and older 34.5 (32.7 – 36.3) 13.6 (12.9 – 14.3) 34.9 (32.4 – 37.7) 69.6 (65.9 – 73.0) 2,183

1–5 years 54.6 (51.2 – 58.2) 28.4 (13.2 – 35.2) 56.0 (53.3 – 58.8) 83.1 (79.7 – 94.4) 255

6–11 years 45.3 (42.3 – 48.4) 23.6 (19.4 – 25.3) 46.0 (42.4 – 49.7) 73.0 (71.0 – 76.9) 284

12–19 years 31.5 (28.8 – 34.5) 13.3 (12.5 – 14.2) 31.3 (27.7 – 34.3) 64.7 (59.3 – 71.5) 676

20–39 years 32.7 (30.4 – 35.1) 13.7 (11.8 – 15.1) 32.4 (29.3 – 36.2) 63.0 (60.6 – 70.6) 377

40–59 years 31.5 (29.2 – 34.0) 12.2 (10.5 – 13.2) 32.5 (28.6 – 35.2) 63.2 (58.7 – 75.3) 333

60 years and older 35.3 (32.8 – 37.9) 15.0 (13.0 – 15.8) 34.7 (31.6 – 39.3) 73.5 (64.4 – 96.3) 258

Table 2.13.a.5. Serum 25-hydroxyvitamin D: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for non-Hispanic whites in the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, 1 year and older 61.9 (60.3 – 63.4) 31.0 (29.1 – 32.6) 63.2 (61.8 – 64.6) 102 (97.8 – 106) 6,698

1–5 years 73.6 (71.3 – 76.0) 49.0 (44.1 – 51.7) 72.3 (70.7 – 74.2) 105 (97.8 – 118) 516

6–11 years 71.1 (68.2 – 74.1) 46.1 (43.5 – 48.1) 69.6 (67.5 – 71.8) 103 (96.1 – 119) 457

12–19 years 65.2 (63.0 – 67.4) 37.4 (35.6 – 40.1) 64.7 (62.9 – 66.6) 107 (100 – 113) 1,050

20–39 years 64.1 (61.8 – 66.5) 33.3 (29.8 – 36.3) 64.3 (61.8 – 66.6) 110 (107 – 115) 1,458

40–59 years 58.9 (56.8 – 61.0) 27.4 (25.9 – 30.2) 60.4 (58.0 – 63.2) 96.7 (92.5 – 103) 1,360

60 years and older 57.4 (55.9 – 58.9) 26.0 (24.2 – 27.7) 59.7 (58.3 – 61.1) 92.9 (90.8 – 97.2) 1,857

Males

Total, 1 year and older 62.4 (60.8 – 64.1) 33.7 (31.8 – 35.4) 63.6 (62.1 – 65.0) 97.4 (93.9 – 103) 3,303

1–5 years 74.1 (71.7 – 76.6) 47.1 (41.5 – 52.3) 72.7 (70.4 – 74.8) 105 (99.2 – 116) 279

6–11 years 72.6 (69.1 – 76.3) 47.1† (41.6 – 52.5) 70.9 (68.0 – 74.8) 105† (96.4 – 136) 219

12–19 years 65.4 (63.2 – 67.7) 40.6 (37.3 – 42.7) 65.3 (63.5 – 67.1) 99.6 (93.5 – 112) 528

20–39 years 61.6 (59.5 – 63.8) 33.5 (30.7 – 36.5) 62.3 (59.6 – 64.7) 96.8 (90.9 – 104) 641

40–59 years 60.7 (58.5 – 63.0) 31.8 (28.4 – 34.0) 62.6 (59.9 – 64.8) 96.1 (90.0 – 104) 691

60 years and older 58.7 (56.9 – 60.5) 30.5 (26.7 – 33.3) 60.0 (58.1 – 61.5) 92.7 (90.1 – 98.7) 945

Females

Total, 1 year and older 61.3 (59.6 – 63.1) 27.9 (25.6 – 30.3) 62.9 (61.0 – 64.5) 107 (102 – 111) 3,395

1–5 years 73.1 (69.8 – 76.5) 49.8 (45.5 – 52.8) 71.9 (69.3 – 75.8) 105 (94.9 – 122) 237

6–11 years 69.4 (66.6 – 72.4) 45.6 (42.7 – 47.6) 68.3 (65.6 – 70.8) 99.9 (94.8 – 109) 238

12–19 years 64.9 (61.7 – 68.3) 34.9 (31.1 – 37.5) 63.9 (61.4 – 67.0) 112 (106 – 127) 522

20–39 years 66.7 (63.5 – 70.0) 33.0 (26.4 – 37.1) 66.6 (63.5 – 69.6) 117 (112 – 128) 817

40–59 years 57.1 (54.6 – 59.7) 24.8 (19.9 – 27.0) 58.4 (55.6 – 61.9) 97.2 (93.4 – 105) 669

60 years and older 56.3 (54.6 – 58.0) 23.9 (22.0 – 25.7) 59.5 (57.8 – 61.2) 93.1 (90.0 – 99.8) 912

† Estimate is subject to greater uncertainty due to small cell size. 
182 2nd 182 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.13.b. Serum 25-hydroxyvitamin D: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in nmol/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 2001–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2001–2002 54.7 (52.6 – 56.8) 22.6 (20.4 – 24.9) 57.1 (55.1 – 59.3) 96.8 (92.4 – 105) 7,807

 2003–2004 55.5 (52.5 – 58.7) 24.2 (20.9 – 26.3) 57.5 (54.7 – 60.6) 97.2 (92.8 – 104) 7,403

 2005–2006 54.3 (51.5 – 57.3) 21.8 (20.1 – 23.5) 57.2 (54.8 – 59.7) 95.9 (91.9 – 103) 7,402

Age group

1–5 years

 2003–2004 68.2 (65.9 – 70.5) 41.3 (37.6 – 44.4) 68.7 (66.8 – 70.6) 97.8 (96.3 – 101) 895

 2005–2006 69.0 (65.7 – 72.5) 41.8 (39.3 – 44.0) 69.1 (64.7 – 72.1) 103 (94.2 – 121) 904

6–11 years

 2001–2002 63.8 (60.5 – 67.3) 36.9 (31.9 – 39.7) 63.7 (60.4 – 66.8) 101 (90.1 – 138) 991

 2003–2004 63.4 (60.2 – 66.7) 34.8 (31.2 – 40.5) 64.5 (61.8 – 66.9) 94.3 (87.5 – 109) 846

 2005–2006 64.2 (60.8 – 67.7) 35.8 (31.9 – 38.6) 64.4 (62.6 – 66.8) 98.8 (92.5 – 129) 922

12–19 years

 2001–2002 55.1 (52.5 – 57.8) 24.5 (20.8 – 27.2) 56.7 (54.2 – 59.1) 96.1 (91.8 – 102) 2,167

 2003–2004 56.2 (52.2 – 60.6) 24.8 (21.0 – 27.3) 57.9 (53.9 – 61.8) 101 (94.1 – 112) 2,059

 2005–2006 54.0 (50.1 – 58.3) 21.2 (17.6 – 23.9) 57.3 (54.0 – 60.7) 96.3 (88.6 – 111) 1,985

20–39 years

 2001–2002 54.1 (51.8 – 56.5) 21.2 (19.4 – 23.1) 56.4 (54.0 – 59.0) 102 (94.8 – 110) 1,691

 2003–2004 54.4 (50.9 – 58.1) 22.5 (19.0 – 25.4) 56.1 (51.9 – 59.9) 104 (95.9 – 110) 1,559

 2005–2006 54.6 (51.1 – 58.4) 21.1 (19.0 – 23.3) 57.0 (54.2 – 60.1) 99.2 (95.5 – 113) 1,703

40–59 years

 2001–2002 54.0 (51.4 – 56.6) 21.4 (18.7 – 24.4) 56.8 (54.6 – 59.8) 94.9 (90.5 – 104) 1,449

 2003–2004 54.7 (51.1 – 58.5) 23.6 (18.7 – 26.9) 56.5 (53.6 – 60.2) 94.5 (89.0 – 102) 1,278

 2005–2006 52.6 (49.6 – 55.9) 20.8 (18.8 – 22.8) 55.5 (52.9 – 58.4) 94.1 (88.9 – 100) 1,382

60 years and older

 2001–2002 52.5 (49.9 – 55.3) 23.1 (21.1 – 24.4) 55.1 (52.4 – 57.7) 91.8 (88.4 – 95.0) 1,509

 2003–2004 55.2 (52.9 – 57.5) 24.2 (21.8 – 25.8) 57.6 (55.2 – 59.7) 94.1 (90.1 – 102) 1,661

 2005–2006 53.1 (50.4 – 55.9) 22.3 (20.4 – 24.3) 56.4 (54.1 – 58.9) 90.4 (87.5 – 93.9) 1,410

Gender

(6 years and older)

Males

 2001–2002 56.5 (54.5 – 58.6) 25.8 (23.8 – 27.2) 58.3 (56.3 – 60.7) 96.0 (91.2 – 105) 3,782

 2003–2004 56.8 (53.6 – 60.2) 27.0 (23.7 – 29.4) 58.6 (55.8 – 61.7) 92.1 (88.8 – 98.2) 3,638

 2005–2006 55.1 (52.4 – 58.0) 23.8 (21.5 – 25.6) 57.7 (55.7 – 60.1) 94.1 (88.1 – 102) 3,603

Females

 2001–2002 53.0 (50.6 – 55.5) 20.5 (18.0 – 22.7) 55.8 (53.5 – 58.1) 98.4 (92.6 – 108) 4,025

 2003–2004 54.3 (51.4 – 57.3) 21.3 (19.2 – 23.5) 56.3 (53.3 – 59.5) 103 (97.3 – 109) 3,765

 2005–2006 53.6 (50.5 – 56.9) 20.5 (18.6 – 22.3) 56.6 (53.8 – 59.5) 97.1 (93.1 – 107) 3,799

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 48.9 (46.2 – 51.8) 23.0 (21.3 – 24.5) 50.1 (47.1 – 52.7) 81.6 (77.3 – 91.2) 1,961

 2003–2004 48.7 (46.0 – 51.6) 22.8 (19.4 – 25.5) 50.2 (47.1 – 53.4) 80.5 (77.2 – 84.1) 1,802

 2005–2006 45.9 (41.9 – 50.2) 20.0 (16.3 – 22.6) 47.3 (43.3 – 52.8) 78.5 (73.0 – 84.5) 1,889

Non-Hispanic Blacks

 2001–2002 32.6 (31.3 – 34.0) 13.3 (10.9 – 14.4) 32.5 (31.1 – 34.2) 66.2 (63.9 – 68.5) 1,821

 2003–2004 36.3 (33.5 – 39.4) 14.3 (12.8 – 15.6) 37.0 (34.0 – 40.7) 69.1 (65.8 – 73.9) 1,914

 2005–2006 33.8 (31.6 – 36.2) 13.9 (13.0 – 14.8) 33.4 (30.7 – 37.1) 68.4 (64.5 – 71.1) 1,932

Non-Hispanic Whites

 2001–2002 60.9 (58.7 – 63.1) 29.9 (28.2 – 31.2) 62.2 (60.2 – 64.2) 102 (95.9 – 110) 3,416

 2003–2004 61.7 (59.3 – 64.2) 30.2 (27.0 – 33.6) 63.2 (60.8 – 65.2) 103 (97.3 – 109) 3,155

 2005–2006 61.0 (59.0 – 63.1) 31.0 (27.5 – 32.4) 62.3 (60.3 – 64.1) 99.0 (95.9 – 108) 3,027
 

 

 

 

 

 

 

 

 

 

140 

120 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5th Percentile 50th Percentile 95th Percentile 100 

80 

60 

80 

70 

60 

50 

40 

30 

50 

40 

30 

20 

10 

 

Total 1−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) (6+y) (6+y) (6+y) (6+y) (6+y) 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

01−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−06

Figure 2.13.b. Serum 25−hydroxyvitamin D: Concentrations by survey cycle 

Selected percentiles in nmol/L (95% confidence intervals), National Health and 


Nutrition Examination Survey, 2001–2006


2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 183183
184 2nd 184 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.13.c.1. Serum 25-hydroxyvitamin D: Prevalence

Prevalence (in percent) of low serum 25-hydroxyvitamin D concentration (< 30 nmol/L) for the U.S. 

population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. 

Sample

size

Prevalence

(95% conf. interval)

Estimated total 

number of persons

Total, 1 year and older 16,604 8.1 (6.7 – 9.8) 23,004,000

Age group

1–5 years 1,799 0.7 (0.4 – 1.3) 146,000

6–11 years 1,768 1.8 (1.3 – 2.6) 442,000

12–19 years 4,044 8.5 (6.5 – 11.2) 2,823,000

20–39 years 3,262 9.5 (7.6 – 11.8) 7,538,000

40–59 years 2,660 9.3 (7.4 – 11.7) 7,343,000

60 years and older 3,071 8.8 (7.3 – 10.5) 4,084,000

Gender

Males 8,145 6.3 (5.0 – 7.9) 8,735,000

Females 8,459 9.9 (8.1 – 11.9) 14,288,000

Race/ethnicity

Mexican Americans 4,275 11.3 (8.7 – 14.6) 2,919,000

Non-Hispanic Blacks 4,349 31.1 (27.4 – 35.1) 10,623,000

Non-Hispanic Whites 6,698 3.6 (3.0 – 4.4) 6,929,000
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 185185

Table 2.13.c.2. Serum 25-hydroxyvitamin D: Prevalence

Prevalence (in percent) of low serum 25-hydroxyvitamin D concentration (between 30–50 nmol/L) for the 

U.S. population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. 

Sample 

size

Prevalence 

(95% conf. interval)

Estimated total 

number of persons

Total, 1 year and older 16,604 23.6 (21.6 – 25.8) 66,859,000

Age group

1–5 years 1,799 8.9 (7.1 – 11.0) 1,799,000

6–11 years 1,768 14.1 (11.5 – 17.2) 3,407,000

12–19 years 4,044 24.2 (21.3 – 27.3) 8,005,000

20–39 years 3,262 26.2 (23.6 – 29.0) 20,908,000

40–59 years 2,660 25.0 (22.2 – 28.0) 19,729,000

60 years and older 3,071 25.5 (23.7 – 27.4) 11,879,000

Gender

Males 8,145 23.1 (20.8 – 25.6) 31,909,000

Females 8,459 24.1 (22.1 – 26.3) 34,955,000

Race/ethnicity

Mexican Americans 4,275 32.9 (29.6 – 36.4) 8,514,000

Non-Hispanic Blacks 4,349 39.5 (37.3 – 41.7) 13,483,000

Non-Hispanic Whites 6,698 18.1 (16.2 – 20.2) 34,769,000
186 2nd 186 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.13.c.3. Serum 25-hydroxyvitamin D: Prevalence

Prevalence (in percent) of low serum 25-hydroxyvitamin D concentration (< 40 nmol/L) for the U.S. 

population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. 

Sample 

size

Prevalence

(95% conf. interval)

Estimated total 

number of persons

Total, 1 year and older 16,604 17.2 (14.7 – 20.0) 49,431,000

Age group

1–5 years 1,799 2.7 (1.8 – 4.0) 541,000

6–11 years 1,768 5.7 (4.2 – 7.7) 1,358,000

12–19 years 4,044 17.1 (13.8 – 21.0) 5,729,000

20–39 years 3,262 19.7 (16.4 – 23.4) 15,722,000

40–59 years 2,660 20.0 (16.6 – 23.9) 16,400,000

60 years and older 3,071 17.8 (15.5 – 20.4) 8,602,000

Gender

Males 8,145 14.6 (12.3 – 17.4) 20,576,000

Females 8,459 19.6 (16.9 – 22.7) 28,869,000

Race/ethnicity

Mexican Americans 4,275 24.4 (20.1 – 29.3) 6,635,000

Non-Hispanic Blacks 4,349 51.6 (46.7 – 56.5) 17,968,000

Non-Hispanic Whites 6,698 9.4 (7.9 – 11.2) 18,114,000
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 187187

Table 2.13.c.4. Serum 25-hydroxyvitamin D: Prevalence

Prevalence (in percent) of high serum 25-hydroxyvitamin D concentration (> 125 nmol/L) for the U.S. 

population aged 1 year and older, National Health and Nutrition Examination Survey, 2003–2006. 

Sample 

size

Prevalence

(95% conf. interval)

Estimated total 

number of persons

Total, 1 year and older 16,604 0.9 (0.6 – 1.2) 2,449,000

Age group

1–5 years 1,799 § §

6–11 years 1,768 § §

12–19 years 4,044 1.4 (0.9 – 2.1) 450,000

20–39 years 3,262 1.5 (0.9 – 2.4) 1,193,000

40–59 years 2,660 0.6‡ (0.3 – 1.2) 498,000‡

60 years and older 3,071 0.3‡ (0.1 – 0.6) 134,000‡

Gender

Males 8,145 0.4 (0.3 – 0.7) 587,000

Females 8,459 1.3 (0.9 – 1.9) 1,867,000

Race/ethnicity

Mexican Americans 4,275 § §

Non-Hispanic Blacks 4,349 § §

Non-Hispanic Whites 6,698 1.2 (0.8 – 1.7) 2,283,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
188 2nd 188 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.13.d.1. Serum 25-hydroxyvitamin D: Prevalence by survey cycle

Prevalence (in percent) of low serum 25-hydroxyvitamin D concentration (< 30 nmol/L) for the U.S. population, 

National Health and Nutrition Examination Survey, 2001–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 6 years and older

 2001–2002 7,807 8.4 (6.8 – 10.3) 21,467,000

 2003–2004 7,403 7.6 (5.5 – 10.5) 20,049,000

 2005–2006 7,402 9.5 (7.3 – 12.2) 25,318,000

Age group

1–5 years

 2003–2004 895 § §

 2005–2006 904 0.7‡ (0.3 – 1.5) 137,000‡

6–11 years

 2001–2002 991 § §

 2003–2004 846 1.5 (0.8 – 2.6) 350,000

 2005–2006 922 2.2 (1.4 – 3.5) 524,000

12–19 years

 2001–2002 2,167 7.0 (4.4 – 11.1) 2,266,000

 2003–2004 2,059 7.0 (4.6 – 10.7) 2,327,000

 2005–2006 1,985 10.0 (6.8 – 14.5) 3,353,000

20–39 years

 2001–2002 1,691 9.5 (7.7 – 11.5) 7,498,000

 2003–2004 1,559 9.3 (6.6 – 12.8) 7,391,000

 2005–2006 1,703 9.6 (6.9 – 13.3) 7,700,000

40–59 years

 2001–2002 1,449 9.4 (7.2 – 12.2) 7,125,000

 2003–2004 1,278 7.5 (4.8 – 11.4) 5,910,000

 2005–2006 1,382 11.0 (8.3 – 14.5) 9,054,000

60 years and older

 2001–2002 1,509 8.8 (6.7 – 11.3) 3,921,000

 2003–2004 1,661 8.3 (6.1 – 11.1) 3,841,000

 2005–2006 1,410 9.3 (7.2 – 11.8) 4,488,000

Gender

(6 years and older)

Males

 2001–2002 3,782 6.2 (4.9 – 7.9) 7,774,000

 2003–2004 3,638 5.3 (3.5 – 8.1) 6,830,000

 2005–2006 3,603 8.0 (6.0 – 10.6) 10,419,000

Females

 2001–2002 4,025 10.4 (8.2 – 13.0) 13,726,000

 2003–2004 3,765 9.8 (7.3 – 13.1) 13,254,000

 2005–2006 3,799 10.9 (8.2 – 14.2) 14,894,000

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 1,961 8.9 (6.7 – 11.6) 1,863,000

 2003–2004 1,802 9.7 (7.1 – 13.3) 2,218,000

 2005–2006 1,889 15.0 (10.2 – 21.5) 3,604,000

Non-Hispanic Blacks

 2001–2002 1,821 37.8 (34.5 – 41.2) 11,654,000

 2003–2004 1,914 28.5 (22.6 – 35.2) 8,872,000

 2005–2006 1,932 37.4 (32.2 – 42.9) 11,915,000

Non-Hispanic Whites

 2001–2002 3,416 3.7 (2.9 – 4.7) 6,654,000

 2003–2004 3,155 3.6 (2.6 – 4.9) 6,423,000

 2005–2006 3,027 4.0 (3.1 – 5.1) 7,240,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 189189

Table 2.13.d.2. Serum 25-hydroxyvitamin D: Prevalence by survey cycle

Prevalence (in percent) of low serum 25-hydroxyvitamin D concentration (between 30–50 nmol/L) for the U.S. 

population, National Health and Nutrition Examination Survey, 2001–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 6 years and older

 2001–2002 7,807 24.0 (21.7 – 26.4) 61,533,000

 2003–2004 7,403 24.5 (21.2 – 28.1) 64,338,000

 2005–2006 7,402 24.5 (21.7 – 27.5) 65,423,000

Age group

1–5 years

 2003–2004 895 8.6 (6.4 – 11.5) 1,741,000

 2005–2006 904 9.2 (6.5 – 12.8) 1,857,000

6–11 years

 2001–2002 991 14.7 (10.9 – 19.6) 3,639,000

 2003–2004 846 13.3 (9.4 – 18.4) 3,199,000

 2005–2006 922 15.0 (11.5 – 19.3) 3,558,000

12–19 years

 2001–2002 2,167 23.6 (20.4 – 27.1) 7,638,000

 2003–2004 2,059 23.8 (19.4 – 28.9) 7,881,000

 2005–2006 1,985 24.6 (20.8 – 28.8) 8,214,000

20–39 years

 2001–2002 1,691 24.8 (21.8 – 28.1) 19,655,000

 2003–2004 1,559 27.5 (23.1 – 32.4) 21,959,000

 2005–2006 1,703 24.9 (21.9 – 28.1) 19,866,000

40–59 years

 2001–2002 1,449 24.3 (21.3 – 27.5) 18,368,000

 2003–2004 1,278 25.1 (21.0 – 29.6) 19,828,000

 2005–2006 1,382 24.8 (20.8 – 29.4) 20,365,000

60 years and older

 2001–2002 1,509 26.9 (23.0 – 31.2) 12,040,000

 2003–2004 1,661 23.8 (21.6 – 26.0) 11,054,000

 2005–2006 1,410 27.3 (24.1 – 30.6) 13,167,000

Gender

(6 years and older)

Males

 2001–2002 3,782 22.8 (20.4 – 25.4) 28,420,000

 2003–2004 3,638 23.6 (19.8 – 27.9) 30,162,000

 2005–2006 3,603 24.3 (21.2 – 27.8) 31,683,000

Females

 2001–2002 4,025 25.1 (22.5 – 27.9) 33,130,000

 2003–2004 3,765 25.4 (22.1 – 28.9) 34,190,000

 2005–2006 3,799 24.6 (21.6 – 27.8) 33,739,000

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 1,961 35.6 (31.0 – 40.5) 7,496,000

 2003–2004 1,802 34.9 (30.6 – 39.5) 7,963,000

 2005–2006 1,889 35.5 (30.0 – 41.3) 8,515,000

Non-Hispanic Blacks

 2001–2002 1,821 40.0 (37.5 – 42.6) 12,350,000

 2003–2004 1,914 42.2 (38.1 – 46.3) 13,140,000

 2005–2006 1,932 39.0 (36.1 – 42.0) 12,422,000

Non-Hispanic Whites

 2001–2002 3,416 18.7 (16.6 – 21.0) 33,627,000

 2003–2004 3,155 18.6 (15.6 – 22.1) 33,594,000

 2005–2006 3,027 18.9 (16.0 – 22.2) 34,271,000
190 2nd 190 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.13.d.3. Serum 25-hydroxyvitamin D: Prevalence by survey cycle

Prevalence (in percent) of low serum 25-hydroxyvitamin D concentration (< 40 nmol/L) for the U.S. population, 

National Health and Nutrition Examination Survey, 2001–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 6 years and older

 2001–2002 7,807 18.2 (15.5 – 21.3) 46,723,000

 2003–2004 7,403 17.2 (13.3 – 21.9) 45,025,000

 2005–2006 7,402 18.9 (15.3 – 23.1) 50,461,000

Age group

1–5 years

 2003–2004 895 3.0 (1.6 – 5.5) 612,000

 2005–2006 904 2.3 (1.4 – 3.7) 467,000

6–11 years

 2001–2002 991 5.3 (3.2 – 8.7) 1,313,000

 2003–2004 846 5.8 (3.4 – 9.7) 1,399,000

 2005–2006 922 5.6 (4.0 – 7.9) 1,338,000

12–19 years

 2001–2002 2,167 17.5 (13.2 – 22.8) 5,660,000

 2003–2004 2,059 15.3 (11.2 – 20.6) 5,078,000

 2005–2006 1,985 18.9 (13.8 – 25.4) 6,325,000

20–39 years

 2001–2002 1,691 19.7 (16.2 – 23.6) 15,557,000

 2003–2004 1,559 19.9 (15.1 – 25.6) 15,829,000

 2005–2006 1,703 19.5 (14.9 – 25.2) 15,587,000

40–59 years

 2001–2002 1,449 19.1 (16.0 – 22.7) 14,488,000

 2003–2004 1,278 18.5 (13.6 – 24.6) 14,620,000

 2005–2006 1,382 21.5 (16.8 – 27.0) 17,595,000

60 years and older

 2001–2002 1,509 20.9 (16.9 – 25.7) 9,371,000

 2003–2004 1,661 16.4 (13.4 – 20.0) 7,646,000

 2005–2006 1,410 19.1 (15.5 – 23.4) 9,241,000

Gender

(6 years and older)

Males

 2001–2002 3,782 14.8 (12.6 – 17.3) 18,450,000

 2003–2004 3,638 14.2 (10.4 – 19.1) 18,138,000

 2005–2006 3,603 16.6 (13.4 – 20.4) 21,606,000

Females

 2001–2002 4,025 21.4 (18.1 – 25.3) 28,325,000

 2003–2004 3,765 20.0 (15.9 – 24.8) 26,932,000

 2005–2006 3,799 21.0 (16.8 – 26.0) 28,849,000

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 1,961 23.3 (19.0 – 28.2) 4,904,000

 2003–2004 1,802 24.5 (19.1 – 30.8) 5,582,000

 2005–2006 1,889 28.9 (21.3 – 37.9) 6,943,000

Non-Hispanic Blacks

 2001–2002 1,821 60.6 (57.1 – 64.1) 18,708,000

 2003–2004 1,914 51.0 (43.9 – 58.1) 15,900,000

 2005–2006 1,932 57.7 (50.3 – 64.7) 18,374,000

Non-Hispanic Whites

 2001–2002 3,416 10.4 (8.6 – 12.4) 18,638,000

 2003–2004 3,155 9.5 (7.0 – 12.8) 17,121,000

 2005–2006 3,027 10.1 (8.1 – 12.6) 18,342,000
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 191191

Table 2.13.d.4. Serum 25-hydroxyvitamin D: Prevalence by survey cycle

Prevalence (in percent) of high serum 25-hydroxyvitamin D concentration (> 125 nmol/L) for the U.S. 

population, National Health and Nutrition Examination Survey, 2001–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Total, 6 years and older

 2001–2002 7,807 0.8 (0.5 – 1.2) 1,998,000

 2003–2004 7,403 1.0 (0.5 – 1.7) 2,547,000

 2005–2006 7,402 0.8 (0.6 – 1.2) 2,224,000

Age group

1–5 years

 2003–2004 895 § §

 2005–2006 904 § §

6–11 years

 2001–2002 991 § §

 2003–2004 846 § §

 2005–2006 922 § §

12–19 years

 2001–2002 2,167 § §

 2003–2004 2,059 1.3 (0.7 – 2.3) 427,000

 2005–2006 1,985 1.4‡ (0.7 – 2.9) 478,000‡

20–39 years

 2001–2002 1,691 1.0 (0.6 – 1.8) 821,000

 2003–2004 1,559 1.7‡ (0.8 – 3.4) 1,334,000‡

 2005–2006 1,703 1.3 (0.7 – 2.4) 1,050,000

40–59 years

 2001–2002 1,449 0.8‡ (0.4 – 1.6) 616,000‡

 2003–2004 1,278 § §

 2005–2006 1,382 § §

60 years and older

 2001–2002 1,509 § §

 2003–2004 1,661 § §

 2005–2006 1,410 § §

Gender

(6 years and older)

Males

 2001–2002 3,782 § §

 2003–2004 3,638 § §

 2005–2006 3,603 0.5‡ (0.2 – 1.0) 649,000‡

Females

 2001–2002 4,025 1.1 (0.7 – 1.7) 1,395,000

 2003–2004 3,765 1.5 (0.8 – 2.9) 2,071,000

 2005–2006 3,799 1.1 (0.7 – 1.9) 1,574,000

Race/ethnicity

(6 years and older)

Mexican Americans

 2001–2002 1,961 § §

 2003–2004 1,802 § §

 2005–2006 1,889 § §

Non-Hispanic Blacks

 2001–2002 1,821 § §

 2003–2004 1,914 § §

 2005–2006 1,932 § §

Non-Hispanic Whites

 2001–2002 3,416 1.0 (0.7 – 1.5) 1,859,000

 2003–2004 3,155 1.3 (0.7 – 2.5) 2,391,000

 2005–2006 3,027 1.1 (0.7 – 1.7) 2,047,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
192 2nd 192 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

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2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 193193

Fatty Acids

Background Information

Nomenclature. Fatty acids are organic acids characterized by long unbranched aliphatic tails (4-

28 carbons) attached to a carboxyl group. Fatty acids usually possess an even number of carbon

atoms; and the carbon chain may contain several unsaturated or exclusively saturated bonds. Thus,

fatty acids differ in chain length, degree of saturation, location of the double bond(s) along the

chain, and whether the orientation of hydrogen atoms adjacent to the double bond is cis or trans.

Fatty acids with no double bonds are referred to as saturated fatty acids (SFA) while those with

one double bond are monounsaturated fatty acids (MUFA). Fatty acids with two or more double

bonds are termed polyunsaturated fatty acids (PUFA). PUFA are most often categorized into two

groups distinguished by a difference in location of the first double bond from the methyl end of

the acyl chain, namely, n-6 and n-3. Linoleic acid (18:2n-6) and alpha-linolenic acid (18:3n-3)

are representatives of these two groups. Each contains 18 carbon atoms but differs in the number

of double bonds (18:2n-6 vs 18:3n-3) and the location of the first double bond (18:2n-6 vs

18:3n-3). In this report, unless marked, all unsaturated fatty acids are assumed to be in the cis

configuration.

Sources and Physiological Functions. Good sources of PUFA include soybean, corn and

cottonseed oils (U.S. Department of Agriculture and U.S. Department of Health and Human

Services 2010). Oils that are rich in MUFA include olive, canola and safflower oils (U.S.

Department of Agriculture and U.S. Department of Health and Human Services 2010). Recent

NHANES data provide information on the major food sources of various fatty acids consumed

in the United States (U.S. National Institutes of Health 2010a and 2010b). Chicken dishes,

desserts, salad dressings, chips, nuts, seeds and pizza are the main sources of n-6 PUFA. The main

sources of n-3 PUFA (C18:3n-3) in the American diet are salad dressings, chicken dishes, desserts,

pizza, bread, mayonnaise and pasta dishes; whereas, the main sources of long-chain n-3 PUFA

(C20:5n-3 and C22:6n-3) are fish and fish mixed dishes. The chief dietary sources of MUFA

(C18:1) are desserts, meats, nuts, seeds, pizza, French fries and Mexican foods. The main sources

of SFA in the American diet are full-fat cheese, pizza and desserts; other sources include chicken

dishes, cured meats, ribs and burgers.

Triacylglycerols (triglycerides), the basic building blocks of fats and oils, are made up of three

fatty acids esterified to a glycerol molecule (Lichtenstein 2005). They are usually composed of 2–3

different kinds of fatty acids per molecule. During digestion, dietary triglycerides from animal

and vegetable fats are hydrolyzed in the small intestine to release free fatty acids. These acids

enter the intestinal cells and are used to resynthesize triglycerides, which become incorporated

into large lipoprotein particles called chylomicrons; these in turn are released into the lymph

prior to entering the plasma. Fatty acids with 10 or fewer carbon atoms can be absorbed from

the gut directly into the bloodstream where they are bound to albumin in the plasma. At distal

sites, triglycerides are again hydrolyzed by lipases before fatty acids can enter cells for further

metabolism. Once inside peripheral cells, free fatty acids provide an immediate source of energy

(fatty acids are the body’s major fuel source) or act as substrate for the biosynthesis of signaling

molecules such as eicosanoids. Free fatty acids are also incorporated into other lipid classes,

such as phospholipids, sphingolipids, and cholesteryl esters, or they may be resynthesized into

triglycerides and stored for later use. Phospholipids, which are critical structural components of

cellular membranes, tend to incorporate unsaturated fatty acids and so serve as a reservoir for

MUFA and PUFA.
194 2nd 194 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Humans are incapable of de novo synthesis of n-6 and n-3 PUFA because they lack the ability to

insert a double bond any closer than 9 carbons from the methyl end. Thus, linoleic (18:2n-6)

and alpha-linolenic (18:3n-3) acid are called “essential” PUFA in that they are required for good

health but must be derived from food sources rather than through endogenous biosynthesis or

metabolism. Both of these fatty acids are metabolized to longer-chain, more highly unsaturated

forms. Note that SFA and MUFA in plasma are not expected to closely reflect dietary intake

because these two classes of fatty acids can be endogenously synthesized from carbohydrates. The

strongest correlations with dietary intake are provided by plasma concentrations of n-3 PUFA and

trans-fatty acids (Sun 2007).

Health Effects. The most common MUFA is oleic acid (C18:1n-9); although humans can

synthesize this fatty acid, it is obtained largely through the diet. Evidence suggests that replacing

dietary carbohydrates with MUFA decreases LDL-cholesterol concentration, but there is little

evidence that MUFA are associated with coronary heart disease (Astrup 2011). Currently, intense

debate surrounds the question whether reduction in dietary SFA reduces risk of cardiovascular

disease (Zelman 2011). At present, the Dietary Guidelines for Americans recommend reduced intake

of SFA (U.S. Department of Agriculture and U.S. Department of Health and Human Services

2010). Restricting fat intake and replacing SFA with other nutrients has revealed added complexity

in the diet-heart issue. According to evidence from human studies, replacing SFA with PUFA lowers

coronary heart disease risk, whereas replacing SFA with carbohydrate either has no benefit (Micha

2010) or may be harmful or beneficial depending upon the quality of the carbohydrate (Jakobsen

2009; Jakobsen 2010). Carbohydrates either rapidly or slowly increase blood glucose; highly refined

carbohydrates are amongst the former, and higher intake of these is associated with greater risk for

development of diabetes. Replacing SFA with highly refined carbohydrates and added sugars may be

increasing heart disease risk through promotion of obesity and diabetes (Hu 2010).

The heart healthy effects of PUFA are most often assessed based on their effects on the concentrations

of total cholesterol, HDL- and LDL-cholesterol, cholesterol ratios and/or triglycerides. Intake of n-6

PUFA helps to lower total cholesterol and LDL-cholesterol, however, high intake of n-6 fatty acids may

suppress HDL-cholesterol levels. In contrast, n-3 fatty acid consumption has been shown to maintain

and even increase HDL status (International Life Sciences Institute 2001). In the United States, the

FDA permits qualified health claims to be made about a diet-disease relationship for cardiovascular

disease; currently, 6 of the 7 permitted claims for cardiovascular disease are related to the MUFA or

PUFA content of nuts, oils and spreads, or fish oil supplements.

Deficiency in the essential fatty acids is determined by use of a plasma triene-to-tetraene ratio

(eicosatrienoic [C20:3n-9]:arachidonic [C20:4n-6] acid); a ratio greater than 0.2 indicates deficiency

(Institute of Medicine 2005). (Note: eicosatrienoic was not part of the plasma fatty acid profile

measured for NHANES 2003-2004.) PUFA deficiency may manifest with neuropathy and skin

problems, such as rough or scaly skin and dermatitis (International Life Sciences Institute 2001).

Intake Recommendations. Because the body makes more than enough SFA to meet metabolic

needs, people have no requirement for these fatty acids. Evidence suggests that SFA are positively

associated with total cholesterol and LDL-cholesterol concentrations and thus with cardiovascular

disease risk. Lowering dietary intake of SFA to no more than 10% of caloric intake and replacing

them with MUFA and PUFA is recommended to reduce the risk of cardiovascular disease; moreover,

lowering the percentage of calories derived from SFA to 7% of calories, can further reduce risk of

cardiovascular disease (U.S. Department of Agriculture and U.S. Department of Health and Human

Services 2010; Cleeman 2001). The National Cholesterol Education Program Expert Panel on

Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (ATP III) recommends
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 195195

that MUFA not exceed 20% of calories (Cleeman 2001). Guidance about adequate intake (AI) is

available for the essential fatty acids. The AI of linoleic acid is 17 g/d for men and 12 g/d for women.

For alpha-linolenic acid, the AI is 1.6 g/d for men and 1.1 g/d for women. Moderate evidence shows

that consumption of about 8 oz of seafood per week, which provides an average of 250 mg per day

of eicosapentaenoic acid (C20:5n-3) and docosahexaenoic acid (C22:6n-3), reduces cardiac deaths

among persons with and without cardiovascular disease (U.S. Department of Agriculture and U.S.

Department of Health and Human Services 2010). This amount of seafood is also associated with

improved infant health outcomes such as visual and cognitive development, when consumed by

pregnant or lactating women (U.S. Department of Agriculture and U.S. Department of Health and

Human Services 2010). Currently, there is not enough evidence to establish upper tolerable limits

for n-3 or n-6 PUFA (Institute of Medicine 2005).

According to the American Heart Association, patients with coronary heart disease should

be encouraged to increase their consumption of eicosapentaenoic acid (C20:5n-3) and

docosahexaenoic acid (C22:6n-3) to about 1 gram per day preferably from oily fish. The

American Heart Association Dietary Guidelines recommend at least two servings of fish per week

(particularly fatty fish) for patients without documented coronary heart disease. In addition,

inclusion of vegetable oils (e.g., soybean, canola,walnut, flaxseed) and food sources (e.g., walnuts,

flaxseeds) high in alpha-linolenic acid (C18:3n-3) is recommended in a healthy diet for the general

population (Kris-Etherton 2002). The American Heart Association recommends 5-10% of energy

from n-6 fatty acids (Harris 2009) while Adult Treatment Panel III recommends up to 10% of

total calories may be consumed from polyunsaturated fats (Cleeman 2001).

Biochemical Indicators and Methods. The long term fatty acid content of the diet is best

represented by the adipose tissue triglyceride content owing to the two-year half-life of adipose tissue

fatty acids. Erythrocytes, due to their 120 day half-life, reflect

intermediate term (weeks-to-months) dietary intake, although

this idea has been challenged by data demonstrating large changes

in the fatty acid composition of erthyrocytes within days of

altering dietary fat intake (Hodson 2008). Serum or plasma

concentrations represent more recent intake (days-to-weeks).

Few studies have compared the fatty acid composition of plasma

with red blood cells to assess which substrate best reflects dietary

intake. In one study, fatty acid correlations with food frequency

questionnaire data were only slightly stronger for erythrocytes

than for plasma (Sun 2007). The triglyceride fraction of plasma

appears to demonstrate the greatest day-to-day variation of any

circulating lipid fraction. Thus, whenever serum or plasma is

collected for fatty acid analysis, fasting is preferred to minimize

the within- and between-person variability at the time of

specimen collection.

Capillary gas chromatography (GC) is the technique most frequently used to separate fatty acids

for quantitative analysis. Detection methods include flame ionization or electron capture negative

chemical ionization mass spectrometry. Internal standards are used to correct for losses during

sample preparation and improve the accuracy and precision of measurements.

Data in NHANES. The data in this report were generated for fasted (≥ 8 hours) adults (≥ 20

years) by use of gas chromatography-mass spectrometry (GC-MS) based on a modification of the

method of Lagerstedt et al. (2001). Plasma fatty acid concentrations are reported in μmol/L units.
196 2nd 196 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Generally, fatty acid data are expressed as percentage by weight of total fatty acids (wt%) although

percentage by mole (mol%) would be more meaningful. The possible advantages of using absolute

concentrations of individual fatty acids have not been well investigated (Hodson 2008). No data

exist on plasma concentrations of fatty acids in NHANES prior to 2003. This report shows firsttime NHANES data for 24 plasma fatty acids including 6 SFA, 7 MUFA, and 11 PUFA; these

data were acquired using surplus plasma from NHANES 2003-2004. The serum specimens were

stored at -70°C until fatty acids were measured during the period 2010–2011. Based on limited

information in the literature about absolute concentrations, these 24 fatty acids are estimated to

comprise at least 90% of the total fatty acids circulating in the plasma in all lipid classes (fatty

acyls, glycerolipids, glycerophospholipids, sphingolipids and sterols). All unsaturated fatty acids

are assumed to be in the cis configuration; trans-fatty acids were not measured.

For more information about polyunsaturated fatty acids, see the Institute of Medicine’s Dietary Reference Intake reports (Institute of Medicine 2005) and fact sheets from the National Institutes of Health,

Office of Dietary Supplements (http://ods.od.nih.gov/FactSheets/Omega3FattyAcidsandHealth.asp).

Highlights

These first-time plasma concentrations of saturated (SFA), monounsaturated (MUFA), and

polyunsaturated (PUFA) fatty acids in the U.S. population showed the following demographic

patterns and characteristics:

•	 In general, fatty acids circulated at lower concentrations in younger adults.

•	 Plasma concentrations of individual fatty acids were generally similar in men and women.

•	 No consistent race/ethnic pattern was observed for plasma fatty acid concentrations,

however heart-healthy polyunsaturated fatty acids showed race/ethnic differences.

All three classes of fatty acids contained representatives at low (< 100 μmol/L) and high

concentrations (> 1,000 μmol/L) (Figure H.2.e).
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 197197

Figure H.2.e. Geometric mean plasma concentrations of individual fatty acids in the U.S. population from fasted adults aged 20 years

and older by race/ethnicity, National Health and Nutrition Examination Survey, 2003-2004.

Error bars represent 95% confidence intervals. The y-axis is displayed on the logarithmic scale.

Saturated (SFA) Monounsaturated (MUFA) Polyunsaturated (PUFA)

20:0 Arachidic acid 22:1n-9 Docosenoic acid 22:5n-6 Docosapentaenoic acid

24:0 Lignoceric acid 14:1n-5 Myristoleic acid 20:2n-6 Eicosadienoic acid

22:0 Doconsanoic acid 20:1n-9 Eicosenoic acid 22:4n-6 Docosatetraenoic acid

14:0 Myristic acid 24:1n-9 Nervonic acid 22:5n-3 Docosapentaenoic acid

18:0 Stearic acid 18:1n-9 cis-Vaccenic acid 20:5n-3 Eicosapentaenoic acid

16:0 Palmitic acid 16:1n-9 Palmitoleic acid 18:3n-6 gamma-Linolenic acid

18:1n-9 Oleic acid 18:3n-3 alpha-Linolenic acid

22:6n-3 Docosahexaenoic acid

20:3n-6 homo-gamma-Linolenic acid

20:4n-6 Arachidonic acid

18:2n-6 Linoleic acid

Plasma concentrations of heart-healthy PUFA showed race/ethnic differences. Geometric mean

concentrations of eicosapentaenoic acid (EPA), which is typically derived from seafood and

supplements, were higher in fasted non-Hispanic blacks and whites compared with MexicanAmerican adults (Figure H.2.f ).

In addition, plasma concentrations of the related long-chain polyunsaturated docosahexaenoic

acid (DHA) were higher in non-Hispanic black compared with Mexican-American and nonHispanic white adults (Figure H.2.g).

Tracking plasma fatty acid concentrations over time will show progress toward more heart-healthy

diets.

1 

10 

100 

1,000 

10,000 

20:0 

24:0 

22:0 

14:0 

18:0 

16:0 

22:1n-9 

14:1n-5 

20:1n-9 

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18:3n-6 

18:3n-3 

22:6n-3 

20:3n-6 

20:4n-6 

18:2n-6 

Saturated Monounsaturated Polyunsaturated 

Geometric mean ( mol/L) 
	

	

	

20 

30 

40 

50 

60 

A. 

b 

a 

a 

10 

0 Mexican American Non-Hispanic black Non-Hispanic white 

EPA ( mol/L) 

180 

160 

40 

20 

0

b 

a 

b 

Mexican American Non-Hispanic black Non-Hispanic white

DHA ( mol/L) 

140 

120 

100 

80 

60 

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198 198 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 199199
200

2nd 200 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.14.a.1. Plasma myristic acid (14:0): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 119 (113 – 125) 42.5 (39.9 – 45.1) 48.1 (46.2 – 50.5) 116 (108 – 123) 308 (282 – 353) 392 (360 – 438) 1,796 Age group 20–39 years 110 (104 – 117) 39.0 (31.1 – 42.5) 45.0 (42.5 – 46.8) 106 (99.0 – 118) 301 (252 – 370) 370 (330 – 533) 603 40–59 years 126 (117 – 136) 46.2 (41.4 – 47.9) 51.8 (47.2 – 56.4) 120 (109 – 132) 329 (287 – 401) 410 (383 – 481) 514 60 years and older 121 (112 – 131) 44.5 (37.9 – 47.5) 50.2 (46.3 – 54.5) 120 (112 – 127) 300 (243 – 366) 329 (307 – 426) 679 Gender Males 120 (112 – 129) 40.6 (34.0 – 45.1) 47.6 (44.8 – 52.6) 118 (105 – 129) 320 (285 – 384) 414 (366 – 508) 856 Females 117 (111 – 124) 44.6 (39.5 – 45.9) 48.3 (45.9 – 50.8) 115 (107 – 121) 303 (258 – 359) 365 (325 – 434) 940 Race/ethnicity Mexican Americans 126 (110 – 144) 41.6† (39.1 – 47.5) 48.5 (40.6 – 52.3) 124 (108 – 144) 342 (304 – 470) 408† (349 – 1,810) 375 Non-Hispanic Blacks 85.8 (78.9 – 93.3) 32.8† (27.9 – 38.3) 39.8 (30.2 – 43.5) 84.3 (72.0 – 95.0) 223 (178 – 283) 261† (229 – 410) 309 Non-Hispanic Whites 123 (116 – 131) 45.6 (38.4 – 47.8) 50.9 (46.5 – 55.8) 119 (110 – 127) 310 (286 – 364) 396 (358 – 464) 982 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 50 100 150 200 

Plasma myristic acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

200

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.14.a. Plasma myristic acid (14:0): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma myristic acid Plasma myristic acid (μmol/L) (μmol/L) 0 50 100 150 200 0 50 100 150 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 201201
202 2nd 202 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.14.a.2. Plasma myristic acid (14:0): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 119 (113 – 125) 57.9 (55.2 – 61.1) 116 (108 – 123) 248 (237 – 266) 1,796

20–39 years 110 (104 – 117) 52.8 (49.4 – 55.9) 106 (99.0 – 118) 240 (209 – 260) 603

40–59 years 126 (117 – 136) 61.8 (56.1 – 66.0) 120 (109 – 132) 266 (248 – 294) 514

60 years and older 121 (112 – 131) 61.4 (54.6 – 67.0) 120 (112 – 127) 238 (224 – 256) 679

Males

Total, 20 years and older 120 (112 – 129) 58.8 (54.7 – 61.5) 118 (105 – 129) 260 (243 – 272) 856

20–39 years 112 (102 – 122) 53.4 (47.6 – 57.8) 106 (93.5 – 122) 245 (209 – 284) 277

40–59 years 133 (120 – 147) 61.8 (57.5 – 70.6) 124 (109 – 154) 279 (265 – 336) 247

60 years and older 115 (106 – 126) 58.2 (47.3 – 67.9) 119 (112 – 123) 226 (201 – 244) 332

Females

Total, 20 years and older 117 (111 – 124) 56.6 (53.6 – 61.5) 115 (107 – 121) 242 (225 – 270) 940

20–39 years 109 (101 – 117) 51.3 (49.2 – 55.4) 106 (95.9 – 119) 226 (193 – 308) 326

40–59 years 120 (111 – 131) 61.5 (51.6 – 64.9) 115 (107 – 123) 249 (226 – 301) 267

60 years and older 126 (114 – 139) 64.1 (51.0 – 73.7) 121 (109 – 143) 244 (227 – 302) 347

Table 2.14.a.3. Plasma myristic acid (14:0): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 126 (110 – 144) 54.6 (49.2 – 62.0) 124 (108 – 144) 277 (244 – 352) 375

20–39 years 122 (95.1 – 155) 51.0 (45.4 – 56.1) 123 (83.9 – 158) 259 (212 – 1,990) 132

40–59 years 133 (112 – 159) 61.2† (46.5 – 76.0) 130 (95.3 – 155) 313† (248 – 387) 93

60 years and older 135 (124 – 146) 68.0 (64.2 – 75.1) 133 (112 – 160) 252 (224 – 315) 150

Males

Total, 20 years and older 126 (102 – 156) 56.3 (49.6 – 62.4) 123 (95.9 – 153) 282 (228 – 410) 188

20–39 years 123 (86.4 – 175) 51.8† (46.6 – 57.2) 123 (67.8 – 214) 274† (202 – 556) 67

40–59 years 136 (104 – 179) 68.5† (54.1 – 82.7) 125 (90.5 – 177) 305† (201 – 721) 48

60 years and older 117 (104 – 131) 65.6† (48.2 – 71.4) 117 (104 – 135) 199† (164 – 390) 73

Females

Total, 20 years and older 126 (110 – 145) 51.4 (40.7 – 65.3) 127 (108 – 152) 268 (240 – 339) 187

20–39 years 119 (92.9 – 153) 50.5† (39.7 – 66.1) 121 (93.6 – 150) 245† (173 – 2,410) 65

40–59 years 130 (99.5 – 169) 50.0† (36.9 – 74.6) 134 (83.1 – 193) 313† (248 – 460) 45

60 years and older 154 (131 – 180) 81.6† (54.5 – 95.1) 153 (120 – 195) 274† (228 – 391) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 203203

Table 2.14.a.4. Plasma myristic acid (14:0): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 85.8 (78.9 – 93.3) 44.8 (38.0 – 50.1) 84.3 (72.0 – 95.0) 161 (146 – 201) 309

20–39 years 81.9 (72.7 – 92.2) 43.6 (33.7 – 48.1) 76.7 (66.9 – 92.1) 149 (128 – 249) 125

40–59 years 91.9 (82.8 – 102) 44.5† (28.4 – 51.6) 93.4 (82.5 – 106) 184† (150 – 249) 98

60 years and older 84.9 (76.3 – 94.5) 46.9† (36.2 – 58.7) 79.7 (71.8 – 95.2) 154† (129 – 188) 86

Males

Total, 20 years and older 87.3 (76.6 – 99.4) 40.9 (31.8 – 46.6) 85.3 (67.2 – 98.7) 170 (148 – 270) 142

20–39 years 82.7 (67.7 – 101) 39.7† (28.5 – 47.0) 71.6 (61.5 – 101) 167† (128 – 466) 57

40–59 years 98.8 (78.8 – 124) 41.2† (29.2 – 55.7) 97.8 (84.0 – 115) 229† (148 – 479) 42

60 years and older 78.0 (64.2 – 94.6) 43.7† (36.0 – 52.8) 67.4 (58.9 – 104) 143† (121 – 187) 43

Females

Total, 20 years and older 84.7 (76.2 – 94.2) 46.5 (39.2 – 51.8) 83.0 (69.2 – 99.1) 153 (135 – 189) 167

20–39 years 81.2 (72.4 – 91.2) 44.2† (33.9 – 51.5) 78.8 (64.6 – 98.7) 144† (110 – 259) 68

40–59 years 87.0 (72.2 – 105) 46.6† (27.8 – 51.5) 86.5 (64.8 – 106) 160† (123 – 690) 56

60 years and older 89.6 (78.3 – 103) 53.5† (39.8 – 63.8) 82.6 (73.5 – 103) 158† (120 – 194) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.14.a.5. Plasma myristic acid (14:0): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 123 (116 – 131) 61.6 (56.2 – 65.5) 119 (110 – 127) 250 (236 – 280) 982

20–39 years 118 (110 – 126) 56.9 (50.1 – 64.0) 115 (103 – 123) 244 (216 – 303) 294

40–59 years 127 (115 – 140) 63.8 (56.4 – 69.1) 120 (108 – 136) 266 (238 – 299) 279

60 years and older 124 (114 – 136) 61.8 (53.5 – 70.8) 121 (116 – 134) 241 (225 – 301) 409

Males

Total, 20 years and older 126 (115 – 137) 61.5 (56.0 – 67.2) 121 (107 – 141) 263 (243 – 273) 465

20–39 years 119 (107 – 133) 58.3 (35.4 – 67.0) 115 (98.2 – 140) 245 (206 – 337) 124

40–59 years 134 (120 – 151) 65.6 (57.8 – 72.3) 124 (108 – 163) 272 (264 – 317) 139

60 years and older 120 (108 – 134) 58.8 (46.7 – 72.3) 121 (115 – 127) 229 (203 – 262) 202

Females

Total, 20 years and older 121 (114 – 128) 61.5 (55.6 – 64.2) 118 (110 – 123) 247 (223 – 303) 517

20–39 years 116 (104 – 129) 55.5 (48.9 – 63.3) 114 (97.3 – 128) 240 (197 – 361) 170

40–59 years 121 (108 – 135) 62.2 (48.3 – 69.0) 115 (104 – 123) 237 (195 – 399) 140

60 years and older 128 (114 – 145) 64.1 (47.6 – 74.7) 124 (110 – 146) 248 (229 – 314) 207
204

2nd 204 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.15.a.1. Plasma palmitic acid (16:0): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 2,710 (2,640 – 2,780) 1,570 (1,420 – 1,610) 1,690 (1,610 – 1,770) 2,630 (2,540 – 2,730) 4,710 (4,500 – 5,030) 5,370 (5,180 – 5,630) 1,805 Age group 20–39 years 2,540 (2,470 – 2,610) 1,440 (1,330 – 1,550) 1,590 (1,480 – 1,670) 2,450 (2,380 – 2,540) 4,550 (4,000 – 5,330) 5,340 (4,740 – 6,860) 609 40–59 years 2,780 (2,680 – 2,880) 1,600 (1,330 – 1,750) 1,830 (1,650 – 1,910) 2,650 (2,530 – 2,800) 4,750 (4,560 – 5,320) 5,410 (5,260 – 5,760) 514 60 years and older 2,890 (2,790 – 2,990) 1,750 (1,610 – 1,860) 1,910 (1,760 – 1,970) 2,820 (2,740 – 2,940) 4,630 (4,390 – 5,160) 5,220 (4,830 – 5,790) 682 Gender Males 2,700 (2,590 – 2,810) 1,560 (1,380 – 1,650) 1,670 (1,570 – 1,790) 2,610 (2,500 – 2,710) 4,730 (4,400 – 5,320) 5,630 (5,090 – 6,090) 863 Females 2,720 (2,640 – 2,800) 1,570 (1,400 – 1,610) 1,710 (1,660 – 1,780) 2,640 (2,540 – 2,760) 4,660 (4,450 – 5,270) 5,350 (4,970 – 5,500) 942 Race/ethnicity Mexican Americans 2,880 (2,710 – 3,050) 1,500† (1,310 – 1,710) 1,750 (1,500 – 1,830) 2,750 (2,620 – 2,970) 5,430 (4,580 – 6,310) 5,980† (5,640 – 6,380) 374 Non-Hispanic Blacks 2,450 (2,340 – 2,570) 1,540† (1,250 – 1,580) 1,590 (1,320 – 1,730) 2,330 (2,240 – 2,480) 4,020 (3,610 – 4,510) 4,570† (4,050 – 8,480) 310 Non-Hispanic Whites 2,720 (2,630 – 2,810) 1,570 (1,380 – 1,610) 1,690 (1,600 – 1,780) 2,650 (2,550 – 2,730) 4,720 (4,430 – 5,270) 5,350 (4,930 – 5,640) 991 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 1000 2000 3000 4000 

Plasma palmitic acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

4000

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.15.a. Plasma palmitic acid (16:0): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma palmitic acid Plasma palmitic acid (μmol/L) (μmol/L) 0 1000 2000 3000 4000 0 1000 2000 3000 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 205205
206 2nd 206 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.15.a.2. Plasma palmitic acid (16:0): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 2,710 (2,640 – 2,780) 1,890 (1,820 – 1,930) 2,630 (2,540 – 2,730) 3,990 (3,820 – 4,360) 1,805

20–39 years 2,540 (2,470 – 2,610) 1,750 (1,660 – 1,810) 2,450 (2,380 – 2,540) 3,790 (3,540 – 4,260) 609

40–59 years 2,780 (2,680 – 2,880) 1,950 (1,910 – 1,990) 2,650 (2,530 – 2,800) 4,160 (3,840 – 4,570) 514

60 years and older 2,890 (2,790 – 2,990) 2,050 (1,960 – 2,140) 2,820 (2,740 – 2,940) 4,050 (3,840 – 4,430) 682

Males

Total, 20 years and older 2,700 (2,590 – 2,810) 1,880 (1,760 – 1,920) 2,610 (2,500 – 2,710) 4,010 (3,790 – 4,430) 863

20–39 years 2,540 (2,400 – 2,690) 1,740 (1,580 – 1,820) 2,470 (2,340 – 2,600) 3,690 (3,420 – 4,540) 282

40–59 years 2,840 (2,690 – 3,000) 1,950 (1,890 – 2,010) 2,700 (2,480 – 2,870) 4,420 (4,030 – 4,760) 247

60 years and older 2,750 (2,640 – 2,860) 1,960 (1,820 – 2,070) 2,730 (2,620 – 2,830) 3,790 (3,530 – 4,380) 334

Females

Total, 20 years and older 2,720 (2,640 – 2,800) 1,920 (1,820 – 1,970) 2,640 (2,540 – 2,760) 3,960 (3,810 – 4,370) 942

20–39 years 2,530 (2,440 – 2,640) 1,760 (1,670 – 1,840) 2,440 (2,350 – 2,580) 3,870 (3,510 – 4,530) 327

40–59 years 2,730 (2,620 – 2,840) 1,960 (1,820 – 2,090) 2,590 (2,530 – 2,760) 3,850 (3,620 – 4,630) 267

60 years and older 3,010 (2,870 – 3,150) 2,180 (2,050 – 2,230) 2,950 (2,760 – 3,150) 4,340 (4,000 – 4,570) 348

Table 2.15.a.3. Plasma palmitic acid (16:0): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 2,880 (2,710 – 3,050) 1,900 (1,720 – 2,050) 2,750 (2,620 – 2,970) 4,540 (4,130 – 5,550) 374

20–39 years 2,730 (2,510 – 2,970) 1,820 (1,390 – 1,970) 2,700 (2,350 – 2,890) 4,410 (3,700 – 5,680) 131

40–59 years 3,090 (2,820 – 3,380) 2,000† (1,480 – 2,330) 2,840 (2,610 – 3,290) 4,940† (4,130 – 6,470) 93

60 years and older 3,140 (3,010 – 3,280) 2,250 (1,970 – 2,420) 3,150 (3,010 – 3,300) 4,530 (3,910 – 5,350) 150

Males

Total, 20 years and older 2,850 (2,580 – 3,160) 1,890 (1,570 – 2,010) 2,690 (2,510 – 3,180) 4,500 (4,020 – 5,950) 188

20–39 years 2,730 (2,320 – 3,220) 1,770† (1,460 – 1,940) 2,540 (2,090 – 3,270) 4,400† (3,600 – 6,350) 67

40–59 years 3,110 (2,670 – 3,630) 1,950† (1,790 – 2,530) 2,830 (2,580 – 3,400) 4,580† (3,880 – 7,970) 48

60 years and older 2,910 (2,740 – 3,080) 2,090† (1,500 – 2,420) 2,900 (2,580 – 3,230) 3,810† (3,500 – 5,010) 73

Females

Total, 20 years and older 2,900 (2,660 – 3,170) 1,930 (1,330 – 2,180) 2,790 (2,450 – 3,280) 4,570 (4,060 – 5,360) 186

20–39 years 2,730 (2,430 – 3,070) 1,840† (1,300 – 2,150) 2,740 (2,230 – 3,080) 4,330† (3,560 – 6,760) 64

40–59 years 3,060 (2,650 – 3,530) 2,050† (1,480 – 2,330) 2,890 (2,460 – 3,500) 4,950† (3,540 – 6,010) 45

60 years and older 3,370 (3,050 – 3,740) 2,370† (2,060 – 2,540) 3,370 (2,780 – 3,790) 5,020† (4,210 – 6,170) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 207207

Table 2.15.a.4. Plasma palmitic acid (16:0): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 2,450 (2,340 – 2,570) 1,750 (1,600 – 1,830) 2,330 (2,240 – 2,480) 3,430 (3,330 – 3,630) 310

20–39 years 2,350 (2,170 – 2,530) 1,680 (1,410 – 1,810) 2,190 (2,070 – 2,480) 3,390 (3,140 – 3,730) 126

40–59 years 2,520 (2,370 – 2,680) 1,790† (1,620 – 1,890) 2,350 (2,270 – 2,590) 3,430† (3,370 – 4,090) 98

60 years and older 2,620 (2,490 – 2,760) 2,030† (1,870 – 2,180) 2,510 (2,430 – 2,760) 3,450† (3,280 – 3,770) 86

Males

Total, 20 years and older 2,450 (2,280 – 2,640) 1,690 (1,550 – 1,810) 2,340 (2,180 – 2,500) 3,550 (3,170 – 4,270) 143

20–39 years 2,320 (2,080 – 2,600) 1,570† (1,310 – 1,770) 2,140 (1,930 – 2,710) 3,410† (2,940 – 9,940) 58

40–59 years 2,620 (2,330 – 2,940) 1,770† (1,380 – 1,950) 2,370 (2,290 – 2,620) 4,060† (2,900 – 8,390) 42

60 years and older 2,520 (2,260 – 2,820) 1,740† (1,640 – 1,910) 2,440 (2,150 – 2,980) 3,290† (3,000 – 4,330) 43

Females

Total, 20 years and older 2,450 (2,300 – 2,620) 1,800 (1,690 – 1,870) 2,330 (2,230 – 2,570) 3,380 (3,210 – 3,680) 167

20–39 years 2,370 (2,170 – 2,580) 1,700† (1,390 – 1,850) 2,230 (2,030 – 2,590) 3,350† (3,110 – 4,210) 68

40–59 years 2,450 (2,230 – 2,680) 1,780† (1,260 – 1,940) 2,330 (2,140 – 2,650) 3,370† (2,930 – 6,230) 56

60 years and older 2,690 (2,520 – 2,870) 2,180† (1,950 – 2,240) 2,530 (2,400 – 2,790) 3,510† (3,260 – 4,220) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.15.a.5. Plasma palmitic acid (16:0): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 2,720 (2,630 – 2,810) 1,900 (1,800 – 1,950) 2,650 (2,550 – 2,730) 3,960 (3,810 – 4,420) 991

20–39 years 2,550 (2,450 – 2,640) 1,720 (1,600 – 1,810) 2,450 (2,370 – 2,590) 3,790 (3,510 – 4,490) 300

40–59 years 2,750 (2,630 – 2,870) 1,950 (1,900 – 1,990) 2,640 (2,500 – 2,800) 4,040 (3,790 – 4,700) 279

60 years and older 2,910 (2,790 – 3,030) 2,040 (1,950 – 2,140) 2,840 (2,730 – 2,990) 4,150 (3,840 – 4,520) 412

Males

Total, 20 years and older 2,700 (2,580 – 2,840) 1,890 (1,750 – 1,940) 2,630 (2,500 – 2,740) 3,960 (3,770 – 4,500) 471

20–39 years 2,530 (2,360 – 2,720) 1,680 (1,540 – 1,800) 2,460 (2,350 – 2,620) 3,630 (3,260 – 5,810) 128

40–59 years 2,810 (2,630 – 2,990) 1,950 (1,890 – 2,010) 2,700 (2,460 – 2,930) 4,280 (3,850 – 4,740) 139

60 years and older 2,780 (2,640 – 2,920) 1,950 (1,760 – 2,070) 2,750 (2,600 – 2,930) 3,830 (3,530 – 4,690) 204

Females

Total, 20 years and older 2,730 (2,640 – 2,820) 1,920 (1,810 – 1,970) 2,650 (2,550 – 2,770) 3,970 (3,810 – 4,500) 520

20–39 years 2,560 (2,410 – 2,710) 1,740 (1,600 – 1,870) 2,440 (2,280 – 2,690) 3,890 (3,490 – 4,960) 172

40–59 years 2,690 (2,570 – 2,830) 1,940 (1,720 – 2,110) 2,580 (2,530 – 2,710) 3,780 (3,510 – 4,690) 140

60 years and older 3,020 (2,860 – 3,200) 2,140 (2,010 – 2,250) 2,960 (2,750 – 3,210) 4,440 (4,030 – 4,660) 208
208

2nd 208 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.16.a.1. Plasma stearic acid (18:0): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 692 (678 – 706) 432 (411 – 444) 471 (440 – 484) 684 (663 – 705) 1,040 (1,020 – 1,100) 1,180 (1,130 – 1,270) 1,806 Age group 20–39 years 649 (635 – 664) 420 (362 – 437) 444 (422 – 468) 638 (624 – 659) 998 (922 – 1,120) 1,150 (1,030 – 1,470) 609 40–59 years 718 (698 – 738) 430 (383 – 473) 481 (426 – 524) 711 (682 – 733) 1,100 (1,040 – 1,160) 1,210 (1,130 – 1,350) 515 60 years and older 724 (703 – 746) 471 (430 – 489) 511 (473 – 534) 731 (697 – 763) 1,030 (976 – 1,120) 1,130 (1,040 – 1,310) 682 Gender Males 690 (671 – 710) 433 (408 – 469) 472 (440 – 483) 673 (644 – 711) 1,090 (1,030 – 1,200) 1,280 (1,170 – 1,360) 864 Females 694 (677 – 712) 421 (399 – 441) 462 (433 – 489) 689 (667 – 712) 1,030 (975 – 1,080) 1,140 (1,080 – 1,190) 942 Race/ethnicity Mexican Americans 710 (677 – 745) 440† (411 – 467) 475 (434 – 492) 710 (666 – 748) 1,150 (1,030 – 1,320) 1,210† (1,170 – 1,330) 374 Non-Hispanic Blacks 676 (655 – 697) 440† (356 – 471) 473 (435 – 495) 669 (645 – 693) 961 (901 – 1,130) 1,130† (998 – 2,010) 310 Non-Hispanic Whites 692 (676 – 709) 421 (408 – 441) 465 (430 – 485) 686 (663 – 709) 1,040 (1,020 – 1,090) 1,170 (1,090 – 1,270) 992 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 500 1000 

Plasma stearic acid

(μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

1000

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.16.a. Plasma stearic acid (18:0): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma stearic acid Plasma stearic acid (μmol/L) (μmol/L) 0 500 1000 0 500 

20−39 40−59 

Females 

60+ 20−39 40−59 

Males 

60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

20−39 

Age (years) 

40−59 60+ 20−39 40−59 

Age (years) 

60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 209209
210 2nd 210 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.16.a.2. Plasma stearic acid (18:0): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 692 (678 – 706) 515 (489 – 531) 684 (663 – 705) 939 (914 – 963) 1,806

20–39 years 649 (635 – 664) 484 (468 – 498) 638 (624 – 659) 870 (831 – 932) 609

40–59 years 718 (698 – 738) 545 (520 – 557) 711 (682 – 733) 989 (955 – 1,030) 515

60 years and older 724 (703 – 746) 552 (538 – 567) 731 (697 – 763) 930 (893 – 976) 682

Males

Total, 20 years and older 690 (671 – 710) 509 (483 – 527) 673 (644 – 711) 967 (930 – 1,010) 864

20–39 years 660 (636 – 686) 484 (469 – 504) 643 (615 – 672) 888 (831 – 1,010) 282

40–59 years 728 (697 – 761) 548 (520 – 571) 711 (646 – 752) 1,020 (997 – 1,040) 248

60 years and older 679 (656 – 703) 514 (472 – 546) 679 (659 – 718) 874 (825 – 960) 334

Females

Total, 20 years and older 694 (677 – 712) 522 (484 – 543) 689 (667 – 712) 916 (892 – 951) 942

20–39 years 639 (620 – 658) 483 (454 – 504) 635 (622 – 658) 849 (817 – 919) 327

40–59 years 709 (685 – 733) 532 (478 – 566) 710 (687 – 733) 934 (900 – 990) 267

60 years and older 763 (736 – 790) 617 (573 – 628) 763 (735 – 786) 971 (914 – 1,020) 348

Table 2.16.a.3. Plasma stearic acid (18:0): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 710 (677 – 745) 503 (485 – 528) 710 (666 – 748) 997 (921 – 1,160) 374

20–39 years 678 (632 – 727) 492 (464 – 510) 664 (594 – 755) 971 (801 – 1,330) 131

40–59 years 756 (710 – 806) 534† (457 – 587) 746 (714 – 770) 1,060† (915 – 1,470) 93

60 years and older 776 (735 – 820) 602 (491 – 646) 767 (720 – 815) 1,060 (961 – 1,180) 150

Males

Total, 20 years and older 705 (651 – 764) 501 (480 – 522) 690 (611 – 766) 1,030 (919 – 1,210) 188

20–39 years 682 (596 – 779) 492† (456 – 508) 647 (540 – 805) 1,040† (830 – 1,330) 67

40–59 years 753 (675 – 841) 529† (469 – 595) 725 (656 – 815) 1,010† (911 – 1,490) 48

60 years and older 726 (678 – 776) 593† (457 – 610) 720 (658 – 783) 896† (832 – 1,300) 73

Females

Total, 20 years and older 716 (677 – 758) 514 (443 – 559) 730 (669 – 777) 996 (885 – 1,140) 186

20–39 years 673 (620 – 732) 481† (340 – 555) 678 (629 – 751) 835† (791 – 1,140) 64

40–59 years 759 (696 – 828) 519† (439 – 624) 756 (700 – 819) 1,070† (859 – 1,410) 45

60 years and older 826 (760 – 897) 624† (541 – 652) 810 (736 – 903) 1,100† (1,050 – 1,250) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 211211

Table 2.16.a.4. Plasma stearic acid (18:0): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 676 (655 – 697) 509 (458 – 540) 669 (645 – 693) 886 (835 – 941) 310

20–39 years 645 (610 – 682) 483 (435 – 514) 641 (587 – 672) 887 (808 – 945) 126

40–59 years 706 (675 – 738) 542† (477 – 567) 693 (664 – 710) 908† (833 – 1,120) 98

60 years and older 705 (681 – 729) 561† (511 – 615) 711 (692 – 753) 834† (806 – 886) 86

Males

Total, 20 years and older 678 (645 – 713) 483 (455 – 524) 663 (618 – 696) 925 (854 – 1,110) 143

20–39 years 651 (602 – 704) 461† (422 – 517) 619 (569 – 687) 897† (803 – 2,540) 58

40–59 years 726 (665 – 792) 544† (475 – 557) 676 (621 – 738) 1,010† (877 – 1,670) 42

60 years and older 662 (608 – 720) 503† (334 – 555) 673 (615 – 738) 830† (782 – 974) 43

Females

Total, 20 years and older 674 (649 – 699) 514 (354 – 567) 674 (644 – 702) 834 (789 – 1,030) 167

20–39 years 639 (604 – 677) 496† (446 – 515) 645 (594 – 667) 833† (715 – 1,090) 68

40–59 years 691 (651 – 733) 526† (353 – 589) 693 (643 – 710) 826† (774 – 2,490) 56

60 years and older 733 (710 – 757) 638† (558 – 668) 718 (696 – 779) 842† (800 – 885) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.16.a.5. Plasma stearic acid (18:0): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 692 (676 – 709) 515 (484 – 533) 686 (663 – 709) 940 (913 – 973) 992

20–39 years 648 (627 – 669) 481 (441 – 507) 635 (614 – 661) 853 (823 – 953) 300

40–59 years 710 (689 – 733) 540 (494 – 565) 705 (675 – 727) 969 (946 – 1,020) 280

60 years and older 726 (700 – 753) 546 (524 – 566) 733 (695 – 770) 940 (900 – 1,020) 412

Males

Total, 20 years and older 691 (669 – 715) 512 (480 – 533) 678 (644 – 720) 959 (919 – 1,010) 472

20–39 years 662 (629 – 696) 484 (433 – 513) 654 (615 – 675) 844 (810 – 1,250) 128

40–59 years 723 (691 – 757) 558 (513 – 576) 709 (640 – 749) 1,020 (975 – 1,040) 140

60 years and older 681 (653 – 711) 508 (471 – 545) 687 (652 – 726) 880 (819 – 1,030) 204

Females

Total, 20 years and older 693 (673 – 713) 516 (481 – 537) 689 (664 – 713) 923 (899 – 954) 520

20–39 years 636 (607 – 666) 460 (427 – 510) 627 (608 – 658) 874 (818 – 1,000) 172

40–59 years 698 (672 – 725) 519 (441 – 554) 699 (675 – 730) 934 (902 – 966) 140

60 years and older 766 (733 – 801) 611 (543 – 630) 767 (735 – 801) 981 (911 – 1,050) 208
212

2nd 212 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.17.a.1. Plasma arachidic acid (20:0): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 23.4 (23.0 – 23.9) 15.1 (14.4 – 15.5) 16.2 (15.4 – 16.7) 23.2 (22.9 – 23.6) 33.6 (32.5 – 35.9) 36.7 (35.0 – 39.1) 1,757 Age group 20–39 years 22.2 (21.6 – 22.9) 14.8 (13.3 – 15.2) 15.6 (15.0 – 16.2) 22.1 (21.4 – 23.0) 31.6 (30.3 – 34.0) 33.9 (32.4 – 36.6) 592 40–59 years 23.9 (23.3 – 24.5) 15.4 (14.4 – 16.3) 16.8 (15.6 – 17.5) 23.5 (22.9 – 24.2) 34.0 (32.4 – 36.8) 36.9 (34.2 – 43.6) 500 60 years and older 24.8 (24.1 – 25.4) 15.6 (13.7 – 16.3) 16.7 (15.6 – 18.0) 24.9 (23.8 – 25.7) 36.1 (33.8 – 38.6) 38.6 (36.5 – 42.2) 665 Gender Males 22.3 (21.8 – 22.8) 14.4 (12.7 – 15.2) 15.5 (14.5 – 16.3) 22.0 (21.7 – 22.3) 32.0 (31.4 – 32.8) 33.8 (32.5 – 36.4) 843 Females 24.5 (23.9 – 25.1) 15.9 (15.0 – 16.5) 16.9 (16.1 – 17.7) 24.3 (23.7 – 25.1) 35.7 (33.6 – 38.4) 38.5 (36.4 – 42.2) 914 Race/ethnicity Mexican Americans 22.5 (21.3 – 23.8) 13.5† (11.4 – 15.6) 15.6 (12.7 – 16.8) 22.4 (21.1 – 23.7) 32.7 (31.2 – 35.5) 35.1† (33.2 – 41.0) 367 Non-Hispanic Blacks 23.2 (22.1 – 24.3) 14.6† (9.41 – 15.3) 15.4 (13.6 – 16.7) 22.7 (21.9 – 23.5) 33.4 (31.2 – 40.8) 35.9† (33.6 – 76.6) 307 Non-Hispanic Whites 23.6 (23.0 – 24.2) 15.3 (14.1 – 15.8) 16.3 (15.3 – 16.8) 23.5 (22.9 – 24.0) 34.1 (32.6 – 36.9) 37.5 (35.6 – 39.5) 962 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 10 20 30 

Plasma arachidic acid

(μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

30

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.17.a. Plasma arachidic acid (20:0): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma arachidic acid Plasma arachidic acid (μmol/L) (μmol/L) 0 10 20 30 0 10 20 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 213213
214 2nd 214 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.17.a.2. Plasma arachidic acid (20:0): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 23.4 (23.0 – 23.9) 17.6 (16.9 – 18.1) 23.2 (22.9 – 23.6) 31.2 (30.4 – 32.1) 1,757

20–39 years 22.2 (21.6 – 22.9) 16.6 (16.0 – 17.2) 22.1 (21.4 – 23.0) 29.5 (28.7 – 30.6) 592

40–59 years 23.9 (23.3 – 24.5) 18.3 (17.5 – 18.8) 23.5 (22.9 – 24.2) 31.4 (30.2 – 32.9) 500

60 years and older 24.8 (24.1 – 25.4) 18.5 (18.0 – 19.1) 24.9 (23.8 – 25.7) 32.9 (31.9 – 34.2) 665

Males

Total, 20 years and older 22.3 (21.8 – 22.8) 16.8 (16.0 – 17.5) 22.0 (21.7 – 22.3) 29.6 (29.0 – 31.0) 843

20–39 years 21.4 (20.6 – 22.3) 16.4 (15.2 – 17.1) 21.0 (20.5 – 21.8) 28.1 (26.1 – 31.6) 275

40–59 years 23.1 (22.2 – 23.9) 17.4 (16.6 – 18.0) 22.7 (22.0 – 23.8) 31.1 (29.2 – 32.1) 241

60 years and older 22.6 (22.1 – 23.0) 16.8 (15.8 – 18.1) 22.4 (21.8 – 23.0) 29.4 (28.9 – 30.4) 327

Females

Total, 20 years and older 24.5 (23.9 – 25.1) 18.7 (18.0 – 19.0) 24.3 (23.7 – 25.1) 32.3 (31.2 – 33.6) 914

20–39 years 23.1 (22.3 – 23.9) 16.9 (16.2 – 18.5) 23.4 (22.6 – 23.8) 30.1 (29.2 – 31.2) 317

40–59 years 24.6 (24.1 – 25.2) 18.9 (18.3 – 19.3) 24.2 (23.5 – 25.3) 32.6 (30.7 – 34.4) 259

60 years and older 26.7 (25.8 – 27.7) 20.1 (18.8 – 21.2) 26.9 (25.7 – 28.1) 35.4 (33.2 – 38.1) 338

Table 2.17.a.3. Plasma arachidic acid (20:0): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 22.5 (21.3 – 23.8) 16.9 (15.3 – 18.2) 22.4 (21.1 – 23.7) 29.6 (27.9 – 33.1) 367

20–39 years 22.2 (20.8 – 23.6) 16.5 (12.4 – 18.3) 21.8 (20.6 – 23.6) 29.5 (27.1 – 36.1) 130

40–59 years 23.0 (21.1 – 25.0) 16.9† (13.9 – 18.7) 23.0 (21.4 – 25.2) 30.6† (27.4 – 41.6) 91

60 years and older 22.7 (21.2 – 24.4) 17.4 (14.6 – 18.7) 22.9 (21.8 – 24.2) 29.3 (27.4 – 34.1) 146

Males

Total, 20 years and older 22.1 (20.6 – 23.7) 16.8 (9.37 – 18.3) 22.4 (20.5 – 23.8) 28.3 (26.9 – 32.7) 185

20–39 years 21.9 (20.2 – 23.9) 16.6† (11.7 – 19.0) 21.7 (19.6 – 23.9) 27.6† (24.5 – 36.3) 66

40–59 years 22.4 (19.9 – 25.3) 15.9† (12.5 – 19.1) 23.0 (19.4 – 25.4) 29.3† (26.8 – 31.9) 47

60 years and older 21.6 (19.5 – 24.0) 15.8† (9.37 – 18.7) 21.9 (20.2 – 24.7) 27.8† (25.5 – 32.7) 72

Females

Total, 20 years and older 23.0 (21.6 – 24.5) 16.8 (15.9 – 18.5) 22.5 (21.3 – 24.0) 31.0 (28.3 – 43.0) 182

20–39 years 22.5 (20.6 – 24.5) 16.4† (12.9 – 18.5) 21.8 (20.2 – 23.9) 29.7† (27.3 – 43.7) 64

40–59 years 23.6 (21.6 – 25.8) 17.3† (15.6 – 19.2) 22.8 (21.3 – 25.3) 31.8† (27.5 – 41.6) 44

60 years and older 23.8 (21.9 – 25.9) 18.5† (13.1 – 20.6) 23.9 (22.2 – 24.5) 30.2† (27.2 – 40.1) 74

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 215215

Table 2.17.a.4. Plasma arachidic acid (20:0): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 23.2 (22.1 – 24.3) 17.4 (15.9 – 18.4) 22.7 (21.9 – 23.5) 31.0 (29.3 – 33.1) 307

20–39 years 22.5 (21.3 – 23.8) 17.0 (13.7 – 18.5) 22.0 (21.4 – 22.8) 30.5 (28.0 – 34.0) 124

40–59 years 24.2 (22.6 – 25.8) 17.0† (15.3 – 19.1) 23.5 (22.5 – 25.2) 31.9† (29.4 – 35.9) 98

60 years and older 23.2 (21.7 – 24.7) 18.3† (15.4 – 18.8) 22.9 (21.1 – 25.6) 29.5† (28.3 – 35.6) 85

Males

Total, 20 years and older 22.4 (21.2 – 23.7) 15.9 (11.7 – 18.2) 21.5 (20.7 – 22.8) 31.2 (29.0 – 35.8) 142

20–39 years 21.4 (19.2 – 23.9) 14.9† (11.3 – 18.3) 20.7 (18.6 – 22.4) 31.2† (23.2 – 71.3) 57

40–59 years 24.3 (21.7 – 27.1) 16.1† (14.7 – 19.7) 23.1 (21.3 – 26.5) 31.7† (29.4 – 48.6) 42

60 years and older 21.6 (20.2 – 23.1) 15.5† (8.59 – 18.4) 21.2 (20.3 – 24.1) 27.9† (25.6 – 33.8) 43

Females

Total, 20 years and older 23.8 (22.6 – 25.1) 18.4 (16.2 – 19.9) 23.4 (22.2 – 25.1) 30.3 (28.7 – 34.8) 165

20–39 years 23.4 (22.0 – 25.0) 18.7† (14.9 – 20.5) 22.8 (21.9 – 25.3) 29.5† (27.8 – 32.5) 67

40–59 years 24.1 (22.7 – 25.6) 17.0† (14.8 – 20.5) 23.6 (21.8 – 25.8) 31.8† (27.7 – 54.9) 56

60 years and older 24.2 (21.5 – 27.1) 18.6† (14.3 – 20.6) 23.9 (19.8 – 29.5) 29.9† (29.3 – 37.1) 42

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.17.a.5. Plasma arachidic acid (20:0): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 23.6 (23.0 – 24.2) 17.6 (16.7 – 18.4) 23.5 (22.9 – 24.0) 31.6 (30.6 – 32.6) 962

20–39 years 22.2 (21.3 – 23.1) 16.5 (15.4 – 17.0) 22.0 (20.9 – 23.5) 29.6 (28.3 – 31.3) 290

40–59 years 23.8 (23.1 – 24.6) 18.4 (17.4 – 19.3) 23.4 (22.9 – 24.1) 31.5 (29.9 – 34.3) 270

60 years and older 25.2 (24.6 – 25.9) 19.0 (18.0 – 19.4) 25.3 (24.4 – 26.4) 33.5 (32.2 – 35.6) 402

Males

Total, 20 years and older 22.4 (21.7 – 23.0) 16.7 (16.1 – 17.6) 22.0 (21.7 – 22.4) 29.8 (29.0 – 31.2) 460

20–39 years 21.2 (20.1 – 22.4) 16.3 (13.6 – 17.0) 20.8 (19.9 – 22.0) 28.5 (25.8 – 32.1) 125

40–59 years 23.0 (21.9 – 24.2) 17.6 (15.6 – 18.6) 22.5 (21.9 – 23.8) 31.1 (28.9 – 32.4) 136

60 years and older 22.9 (22.3 – 23.5) 16.9 (16.1 – 18.3) 22.8 (22.1 – 23.5) 29.6 (29.0 – 31.6) 199

Females

Total, 20 years and older 24.8 (24.0 – 25.7) 18.7 (17.7 – 19.1) 24.8 (23.8 – 25.7) 32.9 (31.4 – 35.6) 502

20–39 years 23.0 (21.9 – 24.3) 16.7 (15.9 – 17.7) 23.6 (22.3 – 24.4) 30.1 (29.3 – 31.3) 165

40–59 years 24.7 (24.0 – 25.5) 18.9 (18.2 – 19.7) 24.2 (23.3 – 25.5) 32.7 (30.5 – 37.1) 134

60 years and older 27.4 (26.4 – 28.4) 20.9 (19.1 – 21.7) 27.6 (26.5 – 28.8) 36.0 (33.6 – 38.6) 203
216

2nd 216 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.18.a.1. Plasma docosanoic acid (22:0): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 69.3 (67.7 – 71.0) 41.5 (38.1 – 43.2) 45.2 (42.9 – 47.6) 69.5 (68.0 – 71.4) 102 (99.0 – 108) 110 (106 – 117) 1,739 Age group 20–39 years 66.5 (65.1 – 67.9) 42.6 (38.0 – 44.3) 46.1 (43.0 – 48.1) 66.5 (65.0 – 68.5) 97.4 (94.4 – 98.7) 99.9 (98.3 – 104) 589 40–59 years 71.8 (68.5 – 75.2) 41.6 (20.1 – 45.2) 46.4 (40.2 – 49.5) 74.0 (68.3 – 76.6) 105 (99.0 – 111) 111 (106 – 134) 496 60 years and older 70.2 (68.2 – 72.4) 39.2 (31.7 – 42.9) 43.0 (40.1 – 46.2) 70.9 (68.1 – 73.4) 109 (105 – 114) 115 (111 – 128) 654 Gender Males 65.8 (64.0 – 67.7) 39.3 (34.2 – 42.4) 43.0 (39.7 – 45.1) 66.2 (64.2 – 68.3) 96.4 (94.9 – 98.2) 105 (98.2 – 111) 834 Females 72.8 (70.4 – 75.2) 43.4 (40.5 – 47.0) 48.4 (45.1 – 50.3) 73.7 (70.7 – 75.6) 106 (102 – 111) 113 (108 – 128) 905 Race/ethnicity Mexican Americans 64.4 (61.3 – 67.7) 39.0† (35.4 – 41.8) 42.0 (37.4 – 46.5) 64.4 (60.9 – 67.4) 95.3 (87.1 – 129) 97.9† (94.9 – 129) 367 Non-Hispanic Blacks 69.6 (66.5 – 73.0) 41.1† (20.8 – 47.2) 46.3 (34.5 – 51.1) 69.4 (64.3 – 74.7) 106 (104 – 107) 115† (107 – 123) 306 Non-Hispanic Whites 70.4 (68.9 – 72.0) 42.6 (39.4 – 43.7) 46.9 (43.4 – 48.5) 70.9 (69.4 – 72.8) 104 (99.2 – 110) 111 (108 – 121) 947 † Estimate is subject to greater uncertainty due to small cell size.
20−39 40−59 60+ 

Plasma docosanoic acid

0 20 40 60 80 100 

(μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

100

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.18.a. Plasma docosanoic acid (22:0): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma docosanoic acid Plasma docosanoic acid (μmol/L) (μmol/L) 0 20 40 60 80 100 0 20 40 60 80 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 217217
218 2nd 218 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.18.a.2. Plasma docosanoic acid (22:0): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 69.3 (67.7 – 71.0) 50.1 (48.7 – 51.5) 69.5 (68.0 – 71.4) 95.3 (93.0 – 97.7) 1,739

20–39 years 66.5 (65.1 – 67.9) 49.7 (48.9 – 51.0) 66.5 (65.0 – 68.5) 89.5 (86.7 – 93.6) 589

40–59 years 71.8 (68.5 – 75.2) 51.9 (47.5 – 55.9) 74.0 (68.3 – 76.6) 96.4 (93.8 – 100) 496

60 years and older 70.2 (68.2 – 72.4) 49.1 (46.2 – 50.7) 70.9 (68.1 – 73.4) 100 (96.1 – 105) 654

Males

Total, 20 years and older 65.8 (64.0 – 67.7) 48.1 (45.1 – 49.7) 66.2 (64.2 – 68.3) 90.5 (88.2 – 92.5) 834

20–39 years 64.7 (62.6 – 66.8) 49.3 (46.8 – 51.2) 63.7 (61.0 – 66.2) 88.7 (82.6 – 93.6) 274

40–59 years 68.7 (65.3 – 72.2) 48.3 (43.0 – 51.4) 70.9 (66.0 – 74.5) 92.2 (89.0 – 96.9) 238

60 years and older 63.1 (60.8 – 65.5) 43.6 (40.8 – 47.0) 64.3 (60.6 – 67.9) 88.2 (85.2 – 91.7) 322

Females

Total, 20 years and older 72.8 (70.4 – 75.2) 52.4 (50.4 – 55.1) 73.7 (70.7 – 75.6) 98.7 (96.1 – 102) 905

20–39 years 68.3 (66.2 – 70.6) 50.9 (48.4 – 51.7) 69.4 (66.8 – 71.6) 91.4 (86.0 – 97.4) 315

40–59 years 74.9 (70.9 – 79.1) 56.6 (48.1 – 58.3) 76.5 (70.1 – 80.6) 99.0 (94.7 – 108) 258

60 years and older 76.6 (73.8 – 79.6) 54.1 (49.1 – 58.5) 75.7 (73.2 – 80.1) 107 (103 – 112) 332

Table 2.18.a.3. Plasma docosanoic acid (22:0): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 64.4 (61.3 – 67.7) 47.8 (41.7 – 51.6) 64.4 (60.9 – 67.4) 87.1 (81.5 – 95.4) 367

20–39 years 64.0 (60.8 – 67.4) 48.4 (42.0 – 50.6) 63.1 (59.7 – 66.8) 85.7 (80.1 – 95.4) 129

40–59 years 66.5 (61.6 – 71.8) 48.1† (35.5 – 55.5) 67.7 (64.3 – 71.7) 87.9† (80.6 – 106) 91

60 years and older 61.4 (56.4 – 66.9) 42.7 (38.6 – 47.2) 61.4 (59.8 – 64.2) 85.0 (74.6 – 120) 147

Males

Total, 20 years and older 64.0 (60.5 – 67.7) 48.2 (38.9 – 52.7) 64.4 (60.8 – 67.1) 85.2 (80.7 – 90.4) 185

20–39 years 65.2 (62.2 – 68.3) 49.6† (31.7 – 55.2) 63.8 (60.7 – 66.9) 86.8† (77.5 – 116) 65

40–59 years 63.1 (56.3 – 70.6) 44.8† (35.5 – 55.6) 65.0 (55.7 – 72.0) 81.4† (74.8 – 97.7) 47

60 years and older 59.6 (53.5 – 66.3) 38.8† (35.0 – 43.0) 61.3 (55.7 – 65.1) 87.6† (68.0 – 112) 73

Females

Total, 20 years and older 64.9 (60.6 – 69.6) 46.5 (41.2 – 50.7) 64.5 (59.9 – 71.3) 92.9 (79.5 – 120) 182

20–39 years 62.5 (57.1 – 68.4) 42.2† (38.2 – 50.3) 61.3 (55.1 – 70.9) 83.6† (76.3 – 97.3) 64

40–59 years 70.7 (65.1 – 76.6) 53.4† (37.4 – 57.1) 68.7 (65.7 – 76.7) 93.5† (85.0 – 106) 44

60 years and older 63.1 (56.5 – 70.6) 47.0† (34.0 – 54.2) 62.0 (57.9 – 66.5) 82.9† (75.2 – 116) 74

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 219219

Table 2.18.a.4. Plasma docosanoic acid (22:0): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 69.6 (66.5 – 73.0) 52.1 (46.8 – 53.9) 69.4 (64.3 – 74.7) 94.2 (91.4 – 101) 306

20–39 years 67.3 (63.9 – 70.8) 52.3 (42.4 – 54.1) 65.0 (62.8 – 71.2) 89.8 (86.7 – 97.6) 124

40–59 years 75.2 (70.9 – 79.7) 53.1† (42.9 – 59.2) 78.6 (71.7 – 82.9) 104† (91.6 – 118) 98

60 years and older 65.6 (61.9 – 69.5) 47.9† (27.8 – 53.2) 65.4 (61.9 – 68.1) 91.3† (81.1 – 118) 84

Males

Total, 20 years and older 66.1 (62.1 – 70.3) 47.6 (33.1 – 53.2) 64.6 (61.6 – 68.4) 90.2 (87.9 – 98.0) 141

20–39 years 63.5 (58.3 – 69.1) 49.2† (34.5 – 53.7) 61.5 (57.0 – 66.1) 86.6† (76.7 – 119) 57

40–59 years 73.0 (64.3 – 83.0) 44.8† (39.5 – 59.2) 74.5 (62.0 – 85.4) 93.5† (86.7 – 171) 42

60 years and older 59.6 (54.0 – 65.7) 41.2† (20.8 – 47.8) 60.2 (53.4 – 67.0) 81.3† (73.0 – 95.8) 42

Females

Total, 20 years and older 72.5 (69.2 – 76.0) 53.8 (50.3 – 56.1) 73.9 (66.3 – 78.4) 99.7 (91.4 – 106) 165

20–39 years 70.6 (65.5 – 76.0) 53.0† (40.9 – 57.0) 71.3 (63.1 – 79.9) 91.5† (88.3 – 96.2) 67

40–59 years 76.8 (72.5 – 81.4) 55.8† (43.3 – 61.0) 80.4 (72.4 – 84.5) 105† (91.6 – 117) 56

60 years and older 69.7 (62.7 – 77.4) 53.1† (41.5 – 55.8) 67.8 (59.0 – 76.7) 100† (79.0 – 123) 42

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.18.a.5. Plasma docosanoic acid (22:0): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 70.4 (68.9 – 72.0) 50.8 (49.4 – 51.7) 70.9 (69.4 – 72.8) 96.4 (94.6 – 98.5) 947

20–39 years 67.1 (65.4 – 68.8) 49.9 (48.6 – 51.2) 68.1 (65.9 – 69.5) 90.6 (85.6 – 96.6) 288

40–59 years 72.3 (68.7 – 76.0) 52.1 (48.5 – 56.3) 74.3 (68.3 – 76.9) 96.5 (93.4 – 103) 267

60 years and older 72.3 (70.5 – 74.1) 50.1 (47.1 – 53.0) 72.5 (70.4 – 74.6) 102 (98.0 – 108) 392

Males

Total, 20 years and older 66.9 (64.8 – 69.0) 49.2 (46.5 – 51.0) 67.8 (65.4 – 69.6) 92.0 (88.7 – 94.5) 453

20–39 years 65.3 (62.5 – 68.2) 49.5 (44.6 – 51.7) 64.4 (61.8 – 68.6) 89.1 (80.8 – 97.3) 125

40–59 years 69.6 (66.0 – 73.4) 49.9 (41.9 – 55.0) 72.3 (66.0 – 75.2) 93.1 (90.8 – 96.8) 134

60 years and older 64.6 (61.6 – 67.7) 46.9 (43.1 – 49.4) 65.3 (62.4 – 69.7) 88.4 (85.6 – 92.0) 194

Females

Total, 20 years and older 73.9 (71.2 – 76.8) 52.8 (49.8 – 56.8) 74.4 (71.7 – 76.5) 99.3 (96.1 – 108) 494

20–39 years 68.8 (66.0 – 71.7) 51.0 (47.5 – 52.1) 69.4 (67.8 – 72.6) 92.8 (85.6 – 98.1) 163

40–59 years 75.0 (69.9 – 80.4) 56.4 (44.8 – 59.1) 76.5 (67.5 – 81.7) 98.6 (94.6 – 110) 133

60 years and older 79.5 (77.1 – 81.9) 57.0 (49.9 – 62.1) 78.5 (75.6 – 83.3) 109 (105 – 113) 198
220

2nd 220 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.19.a.1. Plasma lignoceric acid (24:0): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 54.0 (52.8 – 55.3) 31.2 (29.5 – 33.0) 35.3 (32.7 – 36.8) 53.8 (52.6 – 55.6) 80.9 (79.0 – 83.6) 87.0 (84.9 – 90.2) 1,743 Age group 20–39 years 51.6 (50.3 – 53.0) 31.8 (26.8 – 35.2) 35.6 (32.4 – 36.6) 51.3 (49.8 – 52.9) 73.6 (71.8 – 78.6) 82.0 (76.0 – 88.3) 583 40–59 years 56.4 (54.2 – 58.7) 33.2 (28.7 – 37.6) 37.8 (32.9 – 39.6) 56.6 (54.1 – 59.6) 81.1 (77.4 – 88.0) 86.8 (83.6 – 94.4) 495 60 years and older 54.3 (52.7 – 56.0) 29.1 (21.7 – 31.0) 31.6 (30.0 – 34.2) 54.8 (52.4 – 57.5) 86.9 (81.9 – 91.9) 92.3 (89.1 – 97.5) 665 Gender Males 53.7 (52.2 – 55.2) 30.6 (28.5 – 33.0) 34.6 (30.7 – 37.7) 53.7 (51.6 – 55.8) 80.8 (76.4 – 84.9) 86.1 (84.5 – 93.1) 836 Females 54.4 (52.6 – 56.2) 32.4 (29.8 – 35.0) 35.8 (32.6 – 37.0) 53.8 (52.7 – 56.1) 80.7 (78.7 – 84.5) 87.3 (83.8 – 91.9) 907 Race/ethnicity Mexican Americans 50.4 (47.3 – 53.7) 29.9† (19.2 – 32.6) 32.4 (28.7 – 36.0) 50.1 (47.2 – 53.8) 76.4 (71.1 – 83.0) 80.7† (76.9 – 117) 355 Non-Hispanic Blacks 53.3 (50.5 – 56.2) 30.8† (24.0 – 35.4) 34.8 (27.0 – 38.0) 53.1 (49.6 – 57.0) 79.0 (73.3 – 84.2) 83.9† (79.0 – 112) 302 Non-Hispanic Whites 54.7 (53.4 – 56.0) 31.5 (28.7 – 33.6) 35.8 (33.1 – 37.2) 54.8 (53.0 – 56.5) 81.4 (79.1 – 85.0) 87.2 (85.1 – 92.1) 966 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 20 40 60 80 

Plasma lignoceric acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

80

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.19.a. Plasma lignoceric acid (24:0): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma lignoceric acid Plasma lignoceric acid (μmol/L) (μmol/L) 0 20 40 60 80 0 20 40 60 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 221221
222 2nd 222 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.19.a.2. Plasma lignoceric acid (24:0): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 54.0 (52.8 – 55.3) 39.0 (37.4 – 40.6) 53.8 (52.6 – 55.6) 74.2 (72.2 – 76.4) 1,743

20–39 years 51.6 (50.3 – 53.0) 37.9 (36.6 – 39.6) 51.3 (49.8 – 52.9) 69.0 (66.5 – 71.8) 583

40–59 years 56.4 (54.2 – 58.7) 41.4 (37.9 – 43.7) 56.6 (54.1 – 59.6) 76.0 (72.9 – 79.2) 495

60 years and older 54.3 (52.7 – 56.0) 37.1 (33.6 – 39.5) 54.8 (52.4 – 57.5) 77.9 (76.4 – 81.4) 665

Males

Total, 20 years and older 53.7 (52.2 – 55.2) 39.1 (37.1 – 41.0) 53.7 (51.6 – 55.8) 72.6 (70.8 – 74.8) 836

20–39 years 53.1 (51.2 – 55.1) 39.5 (37.9 – 42.3) 52.1 (50.1 – 55.5) 70.9 (67.6 – 74.9) 272

40–59 years 56.3 (53.6 – 59.0) 41.1 (34.7 – 44.2) 56.1 (53.5 – 60.5) 75.1 (71.7 – 83.1) 238

60 years and older 50.3 (48.3 – 52.4) 33.6 (30.2 – 37.8) 50.4 (47.1 – 55.0) 70.2 (68.5 – 74.4) 326

Females

Total, 20 years and older 54.4 (52.6 – 56.2) 39.0 (36.5 – 41.6) 53.8 (52.7 – 56.1) 76.1 (72.5 – 78.4) 907

20–39 years 50.1 (48.7 – 51.6) 36.6 (34.8 – 37.9) 50.2 (48.9 – 51.9) 67.3 (64.9 – 69.6) 311

40–59 years 56.5 (53.9 – 59.3) 42.2 (39.0 – 43.6) 57.0 (53.5 – 60.0) 76.0 (72.2 – 79.6) 257

60 years and older 57.8 (55.5 – 60.2) 39.9 (35.3 – 42.3) 58.5 (55.2 – 61.3) 82.8 (78.9 – 89.0) 339

Table 2.19.a.3. Plasma lignoceric acid (24:0): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 50.4 (47.3 – 53.7) 37.1 (31.5 – 39.5) 50.1 (47.2 – 53.8) 69.4 (66.9 – 73.7) 355

20–39 years 50.1 (46.5 – 53.9) 37.1 (30.6 – 38.8) 49.2 (44.7 – 56.1) 68.7 (63.7 – 76.3) 120

40–59 years 52.5 (47.5 – 58.0) 38.8† (21.0 – 44.5) 53.3 (47.1 – 59.6) 71.6† (65.8 – 81.4) 89

60 years and older 46.7 (41.5 – 52.7) 33.0 (19.2 – 36.9) 47.1 (40.1 – 53.9) 66.4 (58.7 – 97.3) 146

Males

Total, 20 years and older 52.9 (49.2 – 56.9) 39.3 (33.0 – 43.1) 52.4 (48.7 – 56.2) 72.2 (67.8 – 77.5) 176

20–39 years 54.0 (50.3 – 58.1) 40.7† (37.8 – 44.4) 52.3 (48.1 – 57.7) 69.7† (63.8 – 84.8) 61

40–59 years 52.7 (45.9 – 60.5) 36.7† (28.8 – 45.9) 53.2 (46.0 – 60.5) 72.4† (65.3 – 81.2) 45

60 years and older 46.7 (40.9 – 53.4) 32.2† (19.2 – 36.7) 48.2 (38.4 – 54.3) 69.1† (55.8 – 89.1) 70

Females

Total, 20 years and older 47.6 (44.6 – 50.7) 32.6 (30.3 – 36.7) 46.5 (43.4 – 51.0) 67.8 (61.8 – 71.1) 179

20–39 years 45.3 (41.0 – 50.0) 32.0† (29.8 – 36.6) 43.2 (37.9 – 52.6) 64.6† (57.6 – 78.7) 59

40–59 years 52.2 (47.3 – 57.7) 39.2† (21.0 – 43.4) 53.3 (44.8 – 60.2) 69.6† (61.1 – 83.2) 44

60 years and older 46.7 (39.8 – 54.8) 34.7† (25.4 – 38.0) 45.3 (39.4 – 54.7) 63.8† (54.4 – 97.3) 76

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 223223

Table 2.19.a.4. Plasma lignoceric acid (24:0): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 53.3 (50.5 – 56.2) 38.6 (35.4 – 40.9) 53.1 (49.6 – 57.0) 71.8 (70.3 – 74.3) 302

20–39 years 51.2 (48.2 – 54.5) 37.2 (29.9 – 41.6) 49.9 (48.0 – 55.7) 67.9 (65.1 – 74.2) 123

40–59 years 57.6 (54.6 – 60.8) 40.9† (33.9 – 46.2) 58.1 (54.2 – 63.3) 73.0† (71.0 – 85.7) 95

60 years and older 50.9 (46.1 – 56.2) 37.3† (29.8 – 40.2) 50.8 (43.5 – 55.2) 74.1† (63.0 – 94.8) 84

Males

Total, 20 years and older 53.4 (50.0 – 56.9) 38.8 (27.0 – 43.3) 52.8 (49.1 – 58.6) 71.8 (68.1 – 80.6) 140

20–39 years 51.3 (47.2 – 55.7) 38.8† (26.2 – 43.5) 49.9 (46.3 – 55.9) 66.5† (63.1 – 83.8) 57

40–59 years 58.6 (52.1 – 65.9) 40.9† (32.2 – 48.9) 60.1 (50.6 – 70.1) 73.8† (70.1 – 112) 41

60 years and older 49.2 (44.5 – 54.4) 30.6† (24.0 – 40.9) 49.5 (44.5 – 54.7) 70.7† (62.3 – 79.1) 42

Females

Total, 20 years and older 53.2 (50.1 – 56.6) 38.2 (35.3 – 40.8) 53.3 (49.2 – 57.7) 72.0 (69.6 – 78.2) 162

20–39 years 51.2 (47.7 – 54.8) 36.8† (28.1 – 41.1) 49.7 (46.0 – 57.4) 69.3† (65.3 – 72.9) 66

40–59 years 56.8 (53.8 – 60.1) 39.9† (34.9 – 46.2) 56.6 (51.9 – 61.3) 72.2† (70.3 – 85.2) 54

60 years and older 52.0 (45.0 – 60.1) 39.7† (31.4 – 40.4) 52.4 (40.8 – 62.0) 78.2† (62.0 – 95.2) 42

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.19.a.5. Plasma lignoceric acid (24:0): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 54.7 (53.4 – 56.0) 39.6 (37.7 – 41.6) 54.8 (53.0 – 56.5) 75.3 (73.0 – 77.3) 966

20–39 years 51.8 (50.1 – 53.6) 37.9 (35.9 – 41.2) 51.5 (49.4 – 53.9) 68.9 (66.0 – 72.6) 293

40–59 years 56.7 (54.2 – 59.3) 42.0 (38.6 – 43.2) 57.0 (53.6 – 60.8) 76.4 (72.8 – 80.8) 270

60 years and older 55.7 (54.1 – 57.3) 38.2 (33.4 – 41.0) 56.3 (54.0 – 58.6) 78.7 (76.9 – 82.3) 403

Males

Total, 20 years and older 54.1 (52.5 – 55.8) 39.4 (36.1 – 41.8) 54.7 (51.8 – 56.5) 72.8 (70.5 – 77.2) 461

20–39 years 53.2 (50.5 – 56.0) 39.4 (35.8 – 42.8) 52.5 (49.5 – 56.8) 70.5 (66.0 – 82.9) 126

40–59 years 56.9 (53.9 – 60.0) 42.1 (35.0 – 44.7) 57.1 (53.1 – 61.8) 76.6 (71.7 – 85.9) 135

60 years and older 51.1 (48.6 – 53.8) 34.8 (29.7 – 39.0) 51.4 (47.1 – 56.4) 70.2 (68.4 – 75.8) 200

Females

Total, 20 years and older 55.2 (53.1 – 57.4) 39.7 (36.6 – 42.5) 55.1 (53.0 – 57.3) 76.6 (74.2 – 79.2) 505

20–39 years 50.6 (48.5 – 52.8) 36.7 (32.4 – 41.2) 51.3 (48.6 – 53.2) 67.3 (64.8 – 69.9) 167

40–59 years 56.5 (53.2 – 59.9) 41.8 (38.2 – 43.1) 56.9 (53.0 – 62.0) 76.4 (71.8 – 81.2) 135

60 years and older 59.9 (57.8 – 62.0) 40.9 (36.7 – 44.9) 60.4 (58.3 – 62.5) 85.4 (79.9 – 91.5) 203
224

2nd 224 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.20.a.1. Plasma myristoleic acid (14:1n-5): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 6.57 (6.08 – 7.09) 1.45 (1.31 – 1.56) 1.79 (1.68 – 1.96) 6.50 (5.90 – 6.99) 23.9 (21.4 – 29.3) 32.1 (27.0 – 40.2) 1,808 Age group 20–39 years 6.21 (5.67 – 6.80) 1.47 (1.17 – 1.64) 1.76 (1.64 – 2.01) 6.05 (5.34 – 6.75) 24.0 (19.3 – 32.6) 31.9 (24.8 – 67.0) 610 40–59 years 7.06 (6.30 – 7.90) 1.44 (1.11 – 1.69) 1.86 (1.63 – 2.02) 6.87 (6.20 – 7.62) 25.8 (21.4 – 34.6) 34.6 (27.0 – 52.9) 515 60 years and older 6.39 (5.61 – 7.26) 1.40 (1.17 – 1.67) 1.73 (1.56 – 1.99) 6.40 (5.53 – 7.45) 23.3 (19.3 – 30.9) 26.9 (23.4 – 40.7) 683 Gender Males 6.35 (5.70 – 7.07) 1.25 (1.05 – 1.39) 1.70 (1.41 – 1.82) 6.47 (5.47 – 7.28) 24.9 (22.8 – 29.7) 33.0 (29.4 – 40.6) 865 Females 6.77 (6.26 – 7.32) 1.59 (1.46 – 1.75) 1.94 (1.71 – 2.32) 6.51 (5.96 – 6.96) 23.4 (19.9 – 31.2) 30.7 (23.9 – 48.1) 943 Race/ethnicity Mexican Americans 6.95 (5.89 – 8.20) 1.53† (1.02 – 1.80) 1.82 (1.51 – 2.05) 6.83 (5.44 – 8.30) 26.1 (21.1 – 35.6) 33.1† (27.4 – 68.4) 376 Non-Hispanic Blacks 3.91 (3.50 – 4.38) 1.06† (.703 – 1.17) 1.18 (1.06 – 1.42) 3.78 (3.17 – 4.49) 12.8 (11.5 – 21.4) 20.3† (13.7 – 31.3) 310 Non-Hispanic Whites 7.07 (6.45 – 7.74) 1.65 (1.42 – 1.79) 2.06 (1.80 – 2.33) 6.84 (6.22 – 7.46) 24.9 (22.3 – 31.8) 32.7 (27.0 – 43.6) 992 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 5 10 15 

Plasma myristoleic acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

15

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.20.a. Plasma myristoleic acid (14:1n–5): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma myristoleic acid Plasma myristoleic acid (μmol/L) (μmol/L) 0 5 10 15 0 5 10 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 225225
226 2nd 226 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.20.a.2. Plasma myristoleic acid (14:1n-5): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 6.57 (6.08 – 7.09) 2.41 (2.26 – 2.59) 6.50 (5.90 – 6.99) 18.5 (16.7 – 20.5) 1,808

20–39 years 6.21 (5.67 – 6.80) 2.33 (2.08 – 2.52) 6.05 (5.34 – 6.75) 16.9 (14.8 – 20.4) 610

40–59 years 7.06 (6.30 – 7.90) 2.53 (2.20 – 2.94) 6.87 (6.20 – 7.62) 19.6 (18.0 – 22.2) 515

60 years and older 6.39 (5.61 – 7.26) 2.43 (2.04 – 2.89) 6.40 (5.53 – 7.45) 17.3 (13.1 – 23.4) 683

Males

Total, 20 years and older 6.35 (5.70 – 7.07) 2.20 (2.01 – 2.35) 6.47 (5.47 – 7.28) 18.5 (16.5 – 21.2) 865

20–39 years 6.08 (5.23 – 7.08) 2.10 (2.03 – 2.33) 6.09 (5.00 – 7.32) 16.9 (14.5 – 23.9) 282

40–59 years 7.02 (6.06 – 8.12) 2.27 (1.80 – 2.81) 6.98 (5.49 – 8.66) 21.0 (18.5 – 26.2) 248

60 years and older 5.74 (5.08 – 6.48) 2.26 (1.68 – 2.61) 5.82 (5.44 – 6.42) 13.7 (10.9 – 20.0) 335

Females

Total, 20 years and older 6.77 (6.26 – 7.32) 2.73 (2.52 – 2.96) 6.51 (5.96 – 6.96) 18.4 (15.3 – 21.6) 943

20–39 years 6.34 (5.67 – 7.08) 2.62 (2.06 – 2.94) 5.91 (5.31 – 6.92) 17.2 (13.9 – 22.4) 328

40–59 years 7.09 (6.37 – 7.90) 2.87 (2.39 – 3.40) 6.81 (6.29 – 7.17) 18.7 (13.8 – 23.3) 267

60 years and older 6.97 (5.87 – 8.26) 2.91 (1.76 – 3.22) 6.89 (5.55 – 8.06) 20.0 (16.1 – 23.8) 348

Table 2.20.a.3. Plasma myristoleic acid (14:1n-5): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 6.95 (5.89 – 8.20) 2.26 (1.82 – 2.82) 6.83 (5.44 – 8.30) 19.4 (17.2 – 22.5) 376

20–39 years 6.79 (5.03 – 9.17) 2.11 (1.71 – 2.75) 6.39 (4.79 – 9.10) 18.7 (15.2 – 32.7) 132

40–59 years 7.17 (5.73 – 8.97) 2.48† (1.66 – 2.92) 6.96 (5.46 – 9.72) 20.0† (16.1 – 32.0) 93

60 years and older 7.30 (6.27 – 8.49) 3.03 (2.65 – 3.26) 7.48 (5.22 – 9.67) 16.7 (14.6 – 24.9) 151

Males

Total, 20 years and older 6.79 (5.24 – 8.79) 2.27 (1.79 – 2.93) 6.58 (4.63 – 8.66) 20.0 (15.8 – 24.9) 189

20–39 years 6.79 (4.48 – 10.3) 2.15† (1.85 – 2.42) 6.56 (3.74 – 11.8) 20.2† (15.3 – 42.7) 67

40–59 years 7.08 (4.81 – 10.4) 2.69† (1.87 – 3.06) 6.77 (3.71 – 12.3) 18.8† (14.0 – 52.0) 48

60 years and older 5.90 (4.57 – 7.62) 2.72† (1.76 – 3.30) 5.60 (3.54 – 8.59) 13.6† (9.90 – 18.3) 74

Females

Total, 20 years and older 7.16 (6.00 – 8.55) 2.03 (1.53 – 3.55) 6.86 (5.60 – 9.13) 18.7 (16.3 – 23.9) 187

20–39 years 6.78 (4.95 – 9.30) 1.96† (1.51 – 3.90) 6.02 (4.64 – 9.28) 16.3† (12.9 – 156) 65

40–59 years 7.27 (5.08 – 10.4) 1.93† (1.62 – 2.55) 7.32 (3.75 – 13.4) 22.2† (16.4 – 30.1) 45

60 years and older 8.88 (7.36 – 10.7) 3.63† (2.33 – 4.14) 9.24 (7.46 – 12.9) 17.4† (14.8 – 43.2) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 227227

Table 2.20.a.4. Plasma myristoleic acid (14:1n-5): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 3.91 (3.50 – 4.38) 1.48 (1.28 – 1.69) 3.78 (3.17 – 4.49) 10.4 (8.24 – 12.7) 310

20–39 years 3.95 (3.33 – 4.70) 1.68 (1.29 – 1.90) 3.54 (3.05 – 4.70) 10.2 (7.80 – 12.7) 126

40–59 years 4.07 (3.55 – 4.66) 1.44† (1.07 – 1.66) 4.21 (2.82 – 4.90) 11.7† (8.28 – 21.4) 98

60 years and older 3.51 (3.15 – 3.92) 1.30† (1.07 – 1.63) 3.37 (2.94 – 4.54) 9.13† (7.34 – 11.4) 86

Males

Total, 20 years and older 3.95 (3.24 – 4.80) 1.23 (1.06 – 1.46) 4.23 (2.79 – 4.93) 11.3 (8.12 – 21.6) 143

20–39 years 3.99 (2.96 – 5.36) 1.37† (.992 – 1.92) 3.41 (2.61 – 5.34) 10.7† (7.65 – 61.3) 58

40–59 years 4.30 (3.03 – 6.10) 1.08† (.703 – 1.28) 4.74 (4.11 – 6.89) 12.4† (8.22 – 24.7) 42

60 years and older 3.13 (2.27 – 4.32) 1.30† (1.16 – 1.49) 2.53 (1.60 – 5.17) 8.55† (6.21 – 14.2) 43

Females

Total, 20 years and older 3.89 (3.46 – 4.37) 1.70 (1.43 – 2.07) 3.60 (3.10 – 4.46) 8.84 (7.45 – 12.7) 167

20–39 years 3.93 (3.38 – 4.56) 1.77† (1.45 – 1.94) 3.65 (3.11 – 4.77) 8.32† (6.65 – 12.6) 68

40–59 years 3.90 (3.15 – 4.82) 1.66† (1.44 – 2.21) 3.42 (2.47 – 4.70) 8.90† (7.34 – 19.3) 56

60 years and older 3.78 (3.23 – 4.42) 1.25† (.999 – 2.33) 3.54 (3.09 – 4.69) 9.24† (5.98 – 19.5) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.20.a.5. Plasma myristoleic acid (14:1n-5): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 7.07 (6.45 – 7.74) 2.83 (2.49 – 3.02) 6.84 (6.22 – 7.46) 19.5 (16.9 – 23.0) 992

20–39 years 6.97 (6.26 – 7.77) 2.79 (2.35 – 3.08) 6.61 (5.91 – 7.53) 18.5 (15.1 – 24.6) 300

40–59 years 7.39 (6.43 – 8.48) 2.87 (2.24 – 3.54) 6.97 (6.17 – 7.94) 19.8 (17.0 – 26.7) 280

60 years and older 6.72 (5.80 – 7.78) 2.63 (2.26 – 3.01) 6.72 (5.74 – 7.72) 17.9 (13.8 – 23.5) 412

Males

Total, 20 years and older 6.84 (6.01 – 7.79) 2.47 (2.07 – 2.86) 6.77 (5.68 – 7.91) 18.7 (16.9 – 22.7) 472

20–39 years 6.84 (5.71 – 8.20) 2.39 (2.03 – 2.95) 6.53 (5.25 – 8.27) 17.0 (14.4 – 31.7) 128

40–59 years 7.31 (6.16 – 8.67) 2.49 (1.82 – 2.96) 7.03 (4.70 – 10.4) 21.0 (18.1 – 27.6) 140

60 years and older 6.13 (5.25 – 7.15) 2.43 (1.75 – 2.89) 6.36 (5.73 – 6.86) 15.9 (11.0 – 23.9) 204

Females

Total, 20 years and older 7.28 (6.68 – 7.93) 3.16 (2.81 – 3.49) 6.86 (6.52 – 7.22) 19.6 (15.9 – 23.8) 520

20–39 years 7.09 (5.99 – 8.39) 2.94 (2.37 – 3.49) 6.67 (5.66 – 8.11) 19.0 (14.7 – 28.0) 172

40–59 years 7.46 (6.48 – 8.59) 3.56 (2.06 – 4.04) 6.84 (6.33 – 7.23) 18.9 (13.4 – 43.3) 140

60 years and older 7.27 (5.90 – 8.94) 3.01 (1.59 – 3.69) 7.09 (5.55 – 8.67) 20.7 (17.0 – 25.2) 208
228

2nd 228 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.21.a.1. Plasma palmitoleic acid (16:1n-7): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 217 (205 – 229) 73.3 (65.1 – 78.1) 84.0 (79.0 – 89.6) 213 (196 – 230) 563 (526 – 664) 727 (657 – 806) 1,805 Age group 20–39 years 195 (185 – 205) 72.5 (60.4 – 78.7) 82.0 (75.0 – 84.1) 185 (173 – 194) 539 (450 – 674) 685 (611 – 840) 610 40–59 years 228 (210 – 248) 69.3 (45.2 – 78.1) 82.4 (71.3 – 96.8) 228 (206 – 251) 572 (525 – 772) 770 (671 – 837) 514 60 years and older 238 (220 – 259) 84.8 (65.4 – 94.1) 100 (87.9 – 113) 241 (216 – 263) 559 (528 – 649) 676 (589 – 763) 681 Gender Males 207 (190 – 225) 69.0 (53.4 – 74.7) 77.7 (68.8 – 84.0) 203 (182 – 225) 562 (495 – 683) 682 (578 – 926) 863 Females 226 (214 – 239) 83.2 (71.2 – 88.4) 93.4 (89.1 – 104) 226 (204 – 243) 567 (528 – 679) 729 (630 – 846) 942 Race/ethnicity Mexican Americans 240 (209 – 277) 78.6† (60.0 – 86.2) 87.0 (64.2 – 95.4) 239 (204 – 281) 692 (594 – 780) 769† (699 – 1,110) 375 Non-Hispanic Blacks 157 (148 – 167) 64.8† (47.2 – 68.9) 70.3 (64.2 – 73.2) 151 (142 – 162) 429 (352 – 529) 523† (433 – 755) 310 Non-Hispanic Whites 221 (208 – 236) 74.9 (53.0 – 83.5) 88.9 (79.3 – 96.5) 221 (201 – 237) 554 (522 – 661) 722 (615 – 831) 990 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 100 200 300 400 

Plasma palmitoleic acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

400

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.21.a. Plasma palmitoleic acid (16:1n–7): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma palmitoleic acid Plasma palmitoleic acid (μmol/L) (μmol/L) 0 100 200 300 400 0 100 200 300 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 229229
230 2nd 230 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.21.a.2. Plasma palmitoleic acid (16:1n-7): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 217 (205 – 229) 105 (97.7 – 109) 213 (196 – 230) 454 (424 – 497) 1,805

20–39 years 195 (185 – 205) 92.3 (86.5 – 98.3) 185 (173 – 194) 411 (357 – 472) 610

40–59 years 228 (210 – 248) 106 (92.9 – 118) 228 (206 – 251) 475 (444 – 549) 514

60 years and older 238 (220 – 259) 122 (111 – 135) 241 (216 – 263) 467 (429 – 540) 681

Males

Total, 20 years and older 207 (190 – 225) 92.6 (84.0 – 98.9) 203 (182 – 225) 456 (400 – 525) 863

20–39 years 192 (171 – 215) 83.9 (76.9 – 93.8) 185 (169 – 211) 410 (344 – 542) 282

40–59 years 223 (198 – 251) 97.4 (78.0 – 108) 218 (184 – 273) 501 (450 – 594) 248

60 years and older 207 (191 – 224) 112 (92.6 – 121) 206 (186 – 228) 386 (339 – 450) 333

Females

Total, 20 years and older 226 (214 – 239) 114 (108 – 123) 226 (204 – 243) 453 (421 – 525) 942

20–39 years 197 (185 – 211) 108 (92.2 – 111) 184 (170 – 199) 406 (352 – 495) 328

40–59 years 233 (217 – 250) 126 (99.4 – 133) 231 (213 – 256) 455 (395 – 534) 266

60 years and older 267 (240 – 298) 137 (115 – 150) 271 (242 – 297) 537 (493 – 585) 348

Table 2.21.a.3. Plasma palmitoleic acid (16:1n-7): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 240 (209 – 277) 101 (64.3 – 131) 239 (204 – 281) 571 (498 – 645) 375

20–39 years 223 (181 – 274) 95.2 (60.0 – 129) 221 (175 – 274) 498 (386 – 737) 132

40–59 years 267 (232 – 307) 117† (79.8 – 143) 250 (233 – 272) 639† (545 – 804) 93

60 years and older 277 (262 – 292) 144 (136 – 158) 281 (250 – 308) 510 (446 – 587) 150

Males

Total, 20 years and older 237 (192 – 292) 96.0 (61.6 – 134) 226 (178 – 290) 578 (489 – 687) 188

20–39 years 225 (169 – 300) 92.8† (61.6 – 130) 215 (153 – 314) 519† (406 – 844) 67

40–59 years 267 (194 – 367) 111† (79.8 – 150) 240 (190 – 353) 715† (438 – 942) 48

60 years and older 230 (192 – 276) 131† (64.1 – 158) 223 (180 – 280) 375† (309 – 876) 73

Females

Total, 20 years and older 245 (207 – 291) 110 (61.1 – 132) 248 (188 – 316) 558 (421 – 749) 187

20–39 years 220 (172 – 281) 98.4† (60.0 – 130) 225 (161 – 293) 449† (352 – 1,110) 65

40–59 years 267 (204 – 350) 119† (88.5 – 144) 252 (148 – 396) 613† (517 – 766) 45

60 years and older 328 (284 – 378) 166† (120 – 215) 353 (281 – 398) 528† (469 – 739) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 231231

Table 2.21.a.4. Plasma palmitoleic acid (16:1n-7): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample

10th 50th 90th size

Males and Females

Total, 20 years and older 157 (148 – 167) 78.0 (72.0 – 84.1) 151 (142 – 162) 326 (270 – 421) 310

20–39 years 149 (136 – 164) 78.7 (71.8 – 85.0) 148 (126 – 164) 309 (221 – 430) 126

40–59 years 161 (144 – 180) 72.4† (65.0 – 82.5) 149 (135 – 175) 333† (288 – 508) 98

60 years and older 171 (155 – 189) 89.5† (61.4 – 102) 171 (152 – 193) 316† (265 – 397) 86

Males

Total, 20 years and older 154 (138 – 172) 74.0 (53.3 – 82.4) 157 (132 – 174) 323 (267 – 437) 143

20–39 years 146 (126 – 169) 71.0† (47.0 – 79.4) 145 (122 – 168) 305† (220 – 863) 58

40–59 years 163 (128 – 206) 72.7† (42.6 – 81.3) 168 (115 – 204) 371† (231 – 814) 42

60 years and older 164 (130 – 205) 98.3† (60.8 – 114) 152 (123 – 206) 280† (222 – 430) 43

Females

Total, 20 years and older 159 (142 – 178) 84.4 (71.0 – 90.6) 149 (134 – 172) 331 (254 – 494) 167

20–39 years 152 (132 – 175) 85.4† (75.5 – 94.4) 147 (121 – 167) 314† (190 – 543) 68

40–59 years 160 (134 – 190) 71.3† (58.4 – 86.2) 144 (112 – 205) 317† (255 – 1,360) 56

60 years and older 176 (150 – 205) 89.4† (49.9 – 104) 178 (142 – 235) 322† (251 – 548) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.21.a.5. Plasma palmitoleic acid (16:1n-7): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 221 (208 – 236) 109 (99.2 – 116) 221 (201 – 237) 453 (411 – 498) 990

20–39 years 199 (184 – 215) 95.5 (84.0 – 109) 191 (174 – 207) 406 (348 – 496) 300

40–59 years 229 (208 – 251) 107 (96.8 – 126) 230 (214 – 253) 462 (409 – 525) 279

60 years and older 243 (221 – 267) 125 (114 – 136) 247 (219 – 272) 484 (415 – 556) 411

Males

Total, 20 years and older 208 (189 – 229) 95.8 (81.2 – 108) 202 (182 – 231) 447 (386 – 520) 471

20–39 years 190 (164 – 221) 83.9 (69.1 – 97.2) 185 (159 – 215) 359 (319 – 554) 128

40–59 years 222 (196 – 252) 98.2 (74.3 – 111) 223 (175 – 277) 470 (410 – 582) 140

60 years and older 211 (192 – 232) 113 (92.1 – 124) 201 (182 – 241) 392 (343 – 481) 203

Females

Total, 20 years and older 234 (219 – 249) 122 (108 – 133) 232 (220 – 250) 455 (408 – 538) 519

20–39 years 206 (187 – 228) 109 (91.9 – 118) 194 (173 – 221) 414 (346 – 644) 172

40–59 years 235 (216 – 256) 130 (99.9 – 146) 239 (220 – 257) 452 (362 – 532) 139

60 years and older 273 (238 – 314) 138 (108 – 165) 274 (243 – 303) 550 (460 – 661) 208
232

2nd 232 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.22.a.1. Plasma cis-vaccenic acid (18:1n-7): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 146 (141 – 150) 75.3 (65.1 – 81.0) 83.6 (76.2 – 89.7) 143 (139 – 148) 262 (251 – 274) 303 (283 – 344) 1,762 Age group 20–39 years 131 (126 – 138) 65.6 (58.6 – 75.3) 76.9 (63.3 – 82.7) 129 (122 – 137) 235 (214 – 259) 269 (248 – 344) 589 40–59 years 148 (143 – 154) 76.4 (64.4 – 85.5) 86.6 (75.1 – 95.5) 144 (139 – 150) 282 (251 – 309) 333 (298 – 533) 501 60 years and older 168 (162 – 173) 94.1 (85.3 – 102) 103 (93.4 – 109) 166 (162 – 172) 266 (258 – 297) 301 (278 – 344) 672 Gender Males 145 (139 – 151) 71.5 (62.4 – 81.2) 83.4 (70.4 – 90.3) 141 (135 – 148) 265 (242 – 301) 325 (277 – 390) 845 Females 147 (141 – 153) 77.7 (61.8 – 81.7) 85.8 (75.4 – 92.0) 145 (139 – 151) 260 (240 – 282) 301 (273 – 345) 917 Race/ethnicity Mexican Americans 152 (138 – 166) 65.9† (55.7 – 82.7) 80.9 (58.0 – 93.1) 146 (136 – 164) 304 (258 – 378) 336† (326 – 384) 373 Non-Hispanic Blacks 129 (120 – 138) 69.5† (54.5 – 74.7) 74.8 (68.0 – 80.3) 125 (117 – 134) 237 (206 – 354) 295† (251 – 429) 305 Non-Hispanic Whites 146 (140 – 152) 77.0 (62.1 – 85.4) 86.7 (75.1 – 93.1) 144 (139 – 149) 260 (242 – 275) 298 (275 – 337) 958 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

Plasma cis−vaccenic acid

0 100 200 300 

(μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

300

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.22.a. Plasma cis−vaccenic acid (18:1n–7): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma cis−vaccenic acid Plasma cis−vaccenic acid (μmol/L) (μmol/L) 0 100 200 300 0 100 200 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 233233
234 2nd 234 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.22.a.2. Plasma cis-vaccenic acid (18:1n-7): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 146 (141 – 150) 95.1 (89.2 – 99.8) 143 (139 – 148) 225 (216 – 234) 1,762

20–39 years 131 (126 – 138) 87.0 (78.0 – 93.7) 129 (122 – 137) 200 (190 – 215) 589

40–59 years 148 (143 – 154) 99.9 (92.1 – 104) 144 (139 – 150) 229 (211 – 262) 501

60 years and older 168 (162 – 173) 113 (107 – 119) 166 (162 – 172) 242 (231 – 259) 672

Males

Total, 20 years and older 145 (139 – 151) 95.1 (87.8 – 102) 141 (135 – 148) 222 (210 – 241) 845

20–39 years 132 (126 – 139) 87.9 (73.4 – 94.8) 129 (123 – 138) 197 (184 – 222) 273

40–59 years 149 (139 – 160) 99.8 (85.5 – 105) 146 (133 – 159) 240 (208 – 301) 242

60 years and older 160 (153 – 167) 109 (97.2 – 117) 161 (150 – 168) 226 (215 – 258) 330

Females

Total, 20 years and older 147 (141 – 153) 95.0 (88.5 – 99.8) 145 (139 – 151) 227 (213 – 238) 917

20–39 years 131 (123 – 139) 85.8 (78.0 – 92.8) 129 (119 – 138) 203 (190 – 222) 316

40–59 years 147 (140 – 154) 99.8 (87.5 – 105) 144 (139 – 147) 219 (187 – 301) 259

60 years and older 174 (166 – 181) 117 (107 – 127) 172 (163 – 182) 248 (237 – 273) 342

Table 2.22.a.3. Plasma cis-vaccenic acid (18:1n-7): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 152 (138 – 166) 97.2 (66.3 – 108) 146 (136 – 164) 240 (222 – 324) 373

20–39 years 140 (125 – 157) 83.4 (55.7 – 108) 140 (125 – 154) 226 (188 – 347) 130

40–59 years 168 (146 – 192) 102† (90.0 – 110) 157 (145 – 183) 270† (240 – 375) 92

60 years and older 179 (171 – 187) 123 (73.1 – 139) 177 (169 – 184) 277 (247 – 310) 151

Males

Total, 20 years and older 151 (130 – 176) 94.6 (58.1 – 111) 144 (127 – 178) 255 (217 – 331) 187

20–39 years 139 (117 – 166) 83.3† (58.1 – 108) 136 (117 – 168) 224† (179 – 350) 66

40–59 years 175 (142 – 216) 103† (88.8 – 127) 159 (139 – 212) 321† (229 – 454) 47

60 years and older 167 (142 – 197) 101† (68.8 – 140) 155 (140 – 209) 263† (217 – 634) 74

Females

Total, 20 years and older 152 (142 – 162) 97.2 (72.8 – 104) 153 (137 – 167) 235 (222 – 261) 186

20–39 years 141 (124 – 160) 87.7† (57.9 – 102) 144 (113 – 169) 221† (186 – 410) 64

40–59 years 159 (133 – 191) 98.6† (81.2 – 109) 151 (125 – 188) 246† (197 – 421) 45

60 years and older 190 (173 – 210) 130† (110 – 142) 187 (165 – 214) 284† (228 – 375) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 235235

Table 2.22.a.4. Plasma cis-vaccenic acid (18:1n-7): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 129 (120 – 138) 82.6 (74.8 – 88.4) 125 (117 – 134) 202 (186 – 225) 305

20–39 years 119 (107 – 134) 80.5 (63.7 – 84.9) 112 (99.8 – 134) 184 (155 – 395) 124

40–59 years 133 (121 – 146) 80.1† (69.5 – 89.8) 124 (118 – 135) 204† (187 – 266) 96

60 years and older 151 (145 – 157) 108† (99.6 – 115) 143 (141 – 147) 218† (191 – 303) 85

Males

Total, 20 years and older 129 (119 – 139) 79.8 (71.9 – 84.8) 124 (117 – 134) 205 (185 – 235) 141

20–39 years 118 (104 – 133) 72.2† (54.1 – 82.8) 114 (89.0 – 136) 185† (136 – 435) 57

40–59 years 136 (117 – 158) 80.3† (69.7 – 90.3) 121 (117 – 132) 221† (188 – 409) 41

60 years and older 151 (136 – 168) 108† (89.1 – 116) 147 (136 – 168) 217† (179 – 250) 43

Females

Total, 20 years and older 129 (116 – 143) 84.9 (67.1 – 94.9) 126 (111 – 139) 197 (165 – 284) 164

20–39 years 121 (102 – 142) 82.6† (56.8 – 94.3) 111 (99.1 – 140) 177† (153 – 284) 67

40–59 years 130 (117 – 145) 76.7† (66.9 – 92.1) 128 (115 – 136) 197† (163 – 575) 55

60 years and older 150 (139 – 162) 108† (102 – 124) 141 (136 – 148) 214† (180 – 323) 42

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.22.a.5. Plasma cis-vaccenic acid (18:1n-7): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 146 (140 – 152) 95.8 (89.8 – 102) 144 (139 – 149) 222 (211 – 234) 958

20–39 years 131 (123 – 139) 88.8 (70.0 – 95.5) 127 (120 – 138) 200 (183 – 218) 285

40–59 years 145 (139 – 153) 100 (89.1 – 104) 144 (137 – 149) 219 (199 – 244) 270

60 years and older 168 (162 – 174) 113 (106 – 117) 167 (162 – 172) 247 (231 – 261) 403

Males

Total, 20 years and older 144 (138 – 150) 96.3 (89.6 – 103) 141 (132 – 149) 217 (205 – 240) 456

20–39 years 131 (122 – 140) 92.8 (67.7 – 97.1) 125 (117 – 139) 185 (173 – 229) 121

40–59 years 145 (135 – 156) 99.8 (84.1 – 105) 144 (127 – 158) 224 (203 – 276) 136

60 years and older 161 (153 – 169) 109 (95.0 – 116) 163 (151 – 170) 229 (216 – 260) 199

Females

Total, 20 years and older 148 (141 – 154) 95.6 (87.9 – 103) 147 (141 – 152) 226 (209 – 240) 502

20–39 years 131 (122 – 141) 87.7 (61.8 – 95.4) 130 (121 – 139) 204 (187 – 234) 164

40–59 years 146 (137 – 155) 100 (86.2 – 105) 144 (139 – 148) 212 (180 – 322) 134

60 years and older 174 (166 – 183) 116 (103 – 128) 171 (162 – 183) 253 (235 – 279) 204
236

2nd 236 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.23.a.1. Plasma oleic acid (18:1n-9): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 2,100 (2,050 – 2,150) 1,110 (1,030 – 1,170) 1,220 (1,170 – 1,270) 2,070 (2,000 – 2,150) 3,850 (3,590 – 4,220) 4,480 (4,230 – 4,940) 1,798 Age group 20–39 years 1,910 (1,840 – 1,980) 1,020 (955 – 1,080) 1,130 (1,080 – 1,170) 1,840 (1,750 – 1,970) 3,710 (3,120 – 4,140) 4,190 (3,770 – 8,650) 608 40–59 years 2,160 (2,100 – 2,230) 1,160 (993 – 1,220) 1,280 (1,180 – 1,350) 2,120 (2,010 – 2,190) 4,150 (3,610 – 4,800) 4,790 (4,290 – 5,320) 512 60 years and older 2,360 (2,290 – 2,440) 1,330 (1,290 – 1,400) 1,430 (1,340 – 1,550) 2,380 (2,290 – 2,450) 3,850 (3,490 – 4,410) 4,410 (4,120 – 4,930) 678 Gender Males 2,140 (2,060 – 2,220) 1,140 (1,040 – 1,210) 1,230 (1,160 – 1,300) 2,100 (2,010 – 2,200) 4,110 (3,560 – 4,930) 4,930 (4,500 – 5,530) 858 Females 2,070 (2,000 – 2,140) 1,090 (972 – 1,140) 1,200 (1,130 – 1,270) 2,020 (1,940 – 2,140) 3,810 (3,490 – 4,020) 4,240 (4,030 – 4,400) 940 Race/ethnicity Mexican Americans 2,240 (2,060 – 2,430) 1,110† (871 – 1,240) 1,270 (987 – 1,340) 2,170 (1,990 – 2,470) 4,280 (3,850 – 5,240) 4,940† (4,400 – 6,640) 375 Non-Hispanic Blacks 1,810 (1,730 – 1,890) 1,020† (892 – 1,080) 1,150 (1,010 – 1,180) 1,710 (1,620 – 1,830) 3,180 (2,890 – 3,760) 3,760† (3,350 – 8,200) 308 Non-Hispanic Whites 2,130 (2,060 – 2,200) 1,120 (990 – 1,210) 1,230 (1,140 – 1,320) 2,120 (2,020 – 2,180) 3,840 (3,580 – 4,190) 4,380 (4,160 – 4,930) 986 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 1000 2000 3000 4000 

Plasma oleic acid

(μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

4000

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.23.a. Plasma oleic acid (18:1n–9): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma oleic acid Plasma oleic acid (μmol/L) (μmol/L) 0 1000 2000 3000 4000 0 1000 2000 3000 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 237237
238 2nd 238 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.23.a.2. Plasma oleic acid (18:1n-9): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 2,100 (2,050 – 2,150) 1,360 (1,310 – 1,400) 2,070 (2,000 – 2,150) 3,230 (3,090 – 3,440) 1,798

20–39 years 1,910 (1,840 – 1,980) 1,240 (1,200 – 1,300) 1,840 (1,750 – 1,970) 2,900 (2,710 – 3,160) 608

40–59 years 2,160 (2,100 – 2,230) 1,410 (1,350 – 1,530) 2,120 (2,010 – 2,190) 3,380 (3,100 – 3,660) 512

60 years and older 2,360 (2,290 – 2,440) 1,630 (1,550 – 1,690) 2,380 (2,290 – 2,450) 3,360 (3,200 – 3,640) 678

Males

Total, 20 years and older 2,140 (2,060 – 2,220) 1,360 (1,310 – 1,410) 2,100 (2,010 – 2,200) 3,340 (3,060 – 3,660) 858

20–39 years 1,960 (1,850 – 2,080) 1,240 (1,220 – 1,310) 1,890 (1,770 – 2,060) 2,950 (2,640 – 3,700) 281

40–59 years 2,250 (2,120 – 2,400) 1,410 (1,310 – 1,550) 2,200 (1,970 – 2,350) 3,580 (3,180 – 4,480) 247

60 years and older 2,310 (2,220 – 2,400) 1,600 (1,400 – 1,730) 2,340 (2,170 – 2,420) 3,310 (3,040 – 3,850) 330

Females

Total, 20 years and older 2,070 (2,000 – 2,140) 1,380 (1,300 – 1,410) 2,020 (1,940 – 2,140) 3,180 (2,960 – 3,370) 940

20–39 years 1,860 (1,790 – 1,940) 1,220 (1,140 – 1,300) 1,780 (1,700 – 1,940) 2,820 (2,570 – 3,620) 327

40–59 years 2,080 (2,000 – 2,160) 1,400 (1,330 – 1,520) 2,000 (1,920 – 2,140) 3,100 (2,830 – 3,700) 265

60 years and older 2,410 (2,280 – 2,530) 1,660 (1,480 – 1,740) 2,430 (2,270 – 2,530) 3,410 (3,260 – 3,820) 348

Table 2.23.a.3. Plasma oleic acid (18:1n-9): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 2,240 (2,060 – 2,430) 1,410 (1,250 – 1,500) 2,170 (1,990 – 2,470) 3,680 (3,330 – 4,270) 375

20–39 years 2,080 (1,850 – 2,350) 1,320 (882 – 1,470) 2,020 (1,710 – 2,390) 3,330 (2,900 – 4,590) 132

40–59 years 2,460 (2,220 – 2,730) 1,610† (1,140 – 1,790) 2,330 (2,090 – 2,670) 4,210† (3,520 – 5,160) 93

60 years and older 2,630 (2,460 – 2,820) 1,800 (1,740 – 1,820) 2,650 (2,320 – 2,900) 3,730 (3,570 – 4,720) 150

Males

Total, 20 years and older 2,240 (1,970 – 2,540) 1,410 (1,150 – 1,510) 2,160 (1,820 – 2,570) 3,940 (3,120 – 4,880) 188

20–39 years 2,080 (1,720 – 2,500) 1,340† (989 – 1,480) 1,930 (1,530 – 2,550) 3,390† (2,640 – 5,270) 67

40–59 years 2,560 (2,160 – 3,040) 1,550† (1,280 – 1,980) 2,490 (2,000 – 3,090) 4,270† (3,570 – 5,640) 48

60 years and older 2,460 (2,160 – 2,800) 1,790† (1,030 – 1,830) 2,350 (1,900 – 3,040) 3,440† (3,270 – 4,860) 73

Females

Total, 20 years and older 2,240 (2,060 – 2,450) 1,400 (859 – 1,680) 2,160 (2,020 – 2,500) 3,500 (3,280 – 3,970) 187

20–39 years 2,090 (1,810 – 2,410) 1,240† (831 – 1,570) 2,020 (1,750 – 2,330) 3,210† (2,850 – 4,200) 65

40–59 years 2,350 (2,020 – 2,730) 1,590† (1,080 – 1,770) 2,200 (1,990 – 2,730) 3,760† (2,920 – 5,280) 45

60 years and older 2,800 (2,470 – 3,180) 1,890† (1,600 – 2,040) 2,730 (2,320 – 3,420) 4,260† (3,660 – 5,490) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 239239

Table 2.23.a.4. Plasma oleic acid (18:1n-9): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 1,810 (1,730 – 1,890) 1,210 (1,170 – 1,260) 1,710 (1,620 – 1,830) 2,750 (2,610 – 2,990) 308

20–39 years 1,680 (1,560 – 1,810) 1,170 (1,050 – 1,210) 1,540 (1,470 – 1,760) 2,470 (2,310 – 3,740) 125

40–59 years 1,900 (1,750 – 2,050) 1,240† (1,060 – 1,310) 1,790 (1,640 – 1,970) 2,840† (2,610 – 3,590) 97

60 years and older 2,000 (1,870 – 2,150) 1,400† (1,190 – 1,570) 1,960 (1,800 – 2,190) 2,800† (2,670 – 3,020) 86

Males

Total, 20 years and older 1,850 (1,720 – 1,990) 1,200 (1,140 – 1,240) 1,720 (1,570 – 1,920) 2,930 (2,470 – 4,190) 142

20–39 years 1,710 (1,540 – 1,910) 1,140† (887 – 1,230) 1,560 (1,380 – 1,830) 2,480† (2,400 – 6,770) 57

40–59 years 2,000 (1,730 – 2,310) 1,290† (1,010 – 1,410) 1,850 (1,600 – 2,060) 3,160† (2,570 – 8,560) 42

60 years and older 1,980 (1,730 – 2,270) 1,350† (1,080 – 1,620) 1,960 (1,700 – 2,140) 2,870† (2,440 – 4,520) 43

Females

Total, 20 years and older 1,770 (1,670 – 1,890) 1,210 (1,150 – 1,280) 1,700 (1,600 – 1,840) 2,660 (2,460 – 2,960) 166

20–39 years 1,650 (1,510 – 1,810) 1,160† (1,080 – 1,250) 1,540 (1,470 – 1,710) 2,430† (2,130 – 3,240) 68

40–59 years 1,820 (1,640 – 2,030) 1,200† (863 – 1,280) 1,760 (1,620 – 2,010) 2,620† (2,360 – 6,740) 55

60 years and older 2,010 (1,880 – 2,160) 1,410† (1,280 – 1,590) 1,930 (1,700 – 2,400) 2,780† (2,640 – 3,030) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.23.a.5. Plasma oleic acid (18:1n-9): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 2,130 (2,060 – 2,200) 1,390 (1,320 – 1,480) 2,120 (2,020 – 2,180) 3,240 (3,100 – 3,430) 986

20–39 years 1,940 (1,820 – 2,050) 1,260 (1,140 – 1,360) 1,870 (1,750 – 2,040) 2,820 (2,630 – 3,710) 299

40–59 years 2,150 (2,070 – 2,220) 1,400 (1,320 – 1,550) 2,140 (2,030 – 2,180) 3,320 (3,020 – 3,600) 279

60 years and older 2,390 (2,310 – 2,470) 1,650 (1,530 – 1,730) 2,420 (2,330 – 2,480) 3,410 (3,250 – 3,700) 408

Males

Total, 20 years and older 2,170 (2,070 – 2,280) 1,380 (1,290 – 1,520) 2,150 (2,040 – 2,240) 3,300 (3,030 – 3,630) 468

20–39 years 1,990 (1,830 – 2,170) 1,250 (1,070 – 1,380) 1,960 (1,760 – 2,130) 2,830 (2,610 – 4,110) 128

40–59 years 2,230 (2,080 – 2,380) 1,390 (1,220 – 1,570) 2,200 (1,950 – 2,370) 3,460 (3,020 – 4,000) 140

60 years and older 2,350 (2,240 – 2,460) 1,600 (1,390 – 1,730) 2,400 (2,320 – 2,470) 3,340 (3,070 – 4,100) 200

Females

Total, 20 years and older 2,090 (2,010 – 2,180) 1,390 (1,320 – 1,470) 2,080 (1,970 – 2,160) 3,200 (2,910 – 3,660) 518

20–39 years 1,880 (1,770 – 2,000) 1,260 (1,120 – 1,360) 1,790 (1,670 – 2,010) 2,810 (2,530 – 3,860) 171

40–59 years 2,070 (1,980 – 2,170) 1,410 (1,100 – 1,560) 2,010 (1,890 – 2,160) 3,100 (2,720 – 3,910) 139

60 years and older 2,430 (2,300 – 2,560) 1,670 (1,470 – 1,810) 2,430 (2,250 – 2,540) 3,470 (3,220 – 4,060) 208
240

2nd 240 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.24.a.1. Plasma eicosenoic acid (20:1n-9): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 13.6 (13.2 – 14.1) 6.69 (6.33 – 7.03) 7.56 (6.83 – 7.98) 13.3 (12.8 – 13.8) 25.9 (24.2 – 30.5) 33.1 (29.9 – 38.3) 1,805 Age group 20–39 years 12.6 (12.0 – 13.3) 6.35 (5.53 – 6.66) 6.82 (6.35 – 7.49) 12.1 (11.4 – 12.9) 25.8 (22.7 – 37.3) 34.7 (26.3 – 45.2) 608 40–59 years 13.5 (13.0 – 14.1) 6.96 (4.20 – 7.54) 7.59 (7.00 – 8.25) 13.2 (12.3 – 13.8) 25.7 (23.6 – 31.7) 31.8 (27.6 – 47.0) 514 60 years and older 15.6 (15.1 – 16.1) 8.94 (7.50 – 9.41) 9.74 (8.98 – 10.3) 15.1 (14.7 – 15.8) 26.0 (24.4 – 30.4) 31.1 (28.1 – 39.5) 683 Gender Males 13.9 (13.3 – 14.5) 6.70 (6.12 – 7.50) 7.68 (6.72 – 8.27) 13.5 (12.9 – 14.2) 28.7 (24.6 – 33.4) 37.1 (31.8 – 42.5) 865 Females 13.4 (12.8 – 14.0) 6.66 (5.98 – 7.01) 7.48 (6.83 – 7.84) 13.0 (12.6 – 13.6) 24.9 (23.2 – 26.6) 30.1 (26.1 – 35.3) 940 Race/ethnicity Mexican Americans 15.4 (14.4 – 16.5) 6.86† (6.00 – 8.62) 8.65 (6.33 – 9.25) 14.7 (13.7 – 16.4) 33.1 (27.9 – 40.8) 38.7† (33.2 – 45.9) 376 Non-Hispanic Blacks 11.7 (11.0 – 12.4) 6.11† (5.11 – 6.37) 6.39 (6.08 – 6.85) 11.1 (10.2 – 12.1) 23.4 (21.3 – 28.1) 29.4† (25.1 – 51.3) 310 Non-Hispanic Whites 13.6 (13.1 – 14.2) 6.83 (5.83 – 7.46) 7.63 (6.70 – 8.15) 13.4 (12.9 – 13.8) 24.9 (23.5 – 30.1) 31.7 (26.5 – 39.3) 989 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 5 10 15 20 25 

Plasma eicosenoic acid

(μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

25

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.24.a. Plasma eicosenoic acid (20:1n–9): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma eicosenoic acid Plasma eicosenoic acid (μmol/L) (μmol/L) 0 5 10 15 20 25 0 5 10 15 20 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 241241
242 2nd 242 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.24.a.2. Plasma eicosenoic acid (20:1n-9): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 13.6 (13.2 – 14.1) 8.46 (7.94 – 8.95) 13.3 (12.8 – 13.8) 22.2 (21.4 – 23.2) 1,805

20–39 years 12.6 (12.0 – 13.3) 7.85 (6.91 – 8.20) 12.1 (11.4 – 12.9) 21.6 (20.3 – 23.2) 608

40–59 years 13.5 (13.0 – 14.1) 8.71 (7.75 – 9.34) 13.2 (12.3 – 13.8) 22.3 (20.3 – 24.2) 514

60 years and older 15.6 (15.1 – 16.1) 10.7 (10.3 – 10.9) 15.1 (14.7 – 15.8) 23.1 (21.8 – 24.6) 683

Males

Total, 20 years and older 13.9 (13.3 – 14.5) 8.77 (8.41 – 8.97) 13.5 (12.9 – 14.2) 22.8 (21.2 – 24.7) 865

20–39 years 12.7 (11.9 – 13.5) 7.88 (6.97 – 8.43) 12.2 (11.6 – 13.0) 21.2 (17.8 – 25.8) 282

40–59 years 14.2 (13.3 – 15.3) 8.96 (8.39 – 9.70) 13.9 (12.7 – 14.7) 23.2 (20.5 – 31.5) 248

60 years and older 15.6 (15.0 – 16.2) 10.5 (10.2 – 10.9) 14.9 (14.4 – 16.1) 23.5 (21.8 – 24.8) 335

Females

Total, 20 years and older 13.4 (12.8 – 14.0) 8.18 (7.55 – 8.94) 13.0 (12.6 – 13.6) 21.8 (21.0 – 22.9) 940

20–39 years 12.6 (11.8 – 13.4) 7.74 (6.79 – 8.08) 12.0 (10.8 – 13.2) 21.7 (20.6 – 23.4) 326

40–59 years 12.9 (12.3 – 13.6) 8.31 (7.29 – 9.14) 12.5 (11.9 – 13.1) 19.9 (18.5 – 23.0) 266

60 years and older 15.6 (14.9 – 16.4) 10.8 (9.70 – 11.4) 15.1 (14.6 – 15.9) 22.6 (21.6 – 25.1) 348

Table 2.24.a.3. Plasma eicosenoic acid (20:1n-9): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 15.4 (14.4 – 16.5) 9.39 (8.68 – 10.3) 14.7 (13.7 – 16.4) 26.9 (22.7 – 33.2) 376

20–39 years 14.6 (13.2 – 16.2) 8.93 (7.04 – 9.80) 14.1 (12.1 – 16.5) 23.5 (20.3 – 40.8) 132

40–59 years 16.4 (14.8 – 18.2) 10.2† (7.11 – 11.7) 15.2 (14.6 – 16.8) 28.4† (25.1 – 32.9) 93

60 years and older 17.6 (16.3 – 19.1) 12.0 (10.4 – 12.6) 16.7 (14.6 – 19.8) 27.7 (24.8 – 37.1) 151

Males

Total, 20 years and older 15.4 (13.7 – 17.3) 9.18 (8.78 – 10.6) 14.7 (13.3 – 16.8) 26.1 (21.8 – 39.8) 189

20–39 years 14.5 (12.0 – 17.7) 8.87† (7.99 – 9.35) 14.2 (11.5 – 16.7) 22.7† (17.5 – 40.9) 67

40–59 years 17.0 (14.8 – 19.6) 10.5† (7.01 – 12.6) 15.3 (14.5 – 17.7) 30.7† (24.6 – 44.8) 48

60 years and older 17.0 (14.6 – 19.7) 11.7† (5.88 – 13.3) 16.4 (12.8 – 21.4) 25.3† (21.4 – 59.6) 74

Females

Total, 20 years and older 15.4 (14.4 – 16.5) 9.59 (6.32 – 10.4) 15.0 (13.6 – 16.6) 27.1 (22.6 – 35.3) 187

20–39 years 14.7 (13.2 – 16.4) 9.04† (6.32 – 10.1) 14.0 (11.6 – 16.6) 23.8† (21.5 – 38.7) 65

40–59 years 15.7 (13.3 – 18.6) 9.79† (6.66 – 11.9) 14.9 (12.8 – 18.8) 26.4† (19.1 – 38.4) 45

60 years and older 18.3 (15.9 – 21.0) 11.9† (9.58 – 13.0) 16.8 (14.6 – 21.4) 32.3† (24.3 – 38.0) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 243243

Table 2.24.a.4. Plasma eicosenoic acid (20:1n-9): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 11.7 (11.0 – 12.4) 7.28 (6.35 – 7.86) 11.1 (10.2 – 12.1) 20.0 (17.7 – 22.1) 310

20–39 years 10.9 (9.78 – 12.1) 6.75 (6.07 – 7.51) 9.90 (9.05 – 11.4) 19.7 (15.0 – 25.9) 126

40–59 years 12.1 (10.9 – 13.3) 7.40† (5.83 – 8.31) 11.4 (10.1 – 12.4) 20.0† (16.8 – 33.4) 98

60 years and older 13.4 (12.7 – 14.1) 9.43† (8.18 – 9.88) 13.1 (12.2 – 14.6) 19.7† (17.7 – 24.3) 86

Males

Total, 20 years and older 11.9 (11.1 – 12.8) 7.12 (6.18 – 7.71) 11.0 (9.88 – 12.3) 21.2 (17.6 – 35.8) 143

20–39 years 10.9 (9.62 – 12.4) 6.33† (5.90 – 7.47) 9.97 (8.73 – 12.2) 17.2† (14.7 – 35.2) 58

40–59 years 12.8 (10.5 – 15.6) 7.86† (5.24 – 8.80) 11.1 (9.28 – 14.0) 21.3† (16.6 – 61.1) 42

60 years and older 13.6 (12.4 – 15.0) 9.07† (6.71 – 10.5) 12.3 (11.2 – 15.0) 22.3† (18.9 – 25.7) 43

Females

Total, 20 years and older 11.5 (10.4 – 12.7) 7.29 (6.37 – 7.99) 11.3 (9.96 – 12.5) 19.0 (15.8 – 25.1) 167

20–39 years 10.9 (9.36 – 12.6) 6.88† (5.96 – 7.70) 9.60 (8.86 – 11.9) 20.2† (14.6 – 26.0) 68

40–59 years 11.5 (10.2 – 12.9) 7.20† (5.09 – 7.95) 11.6 (9.98 – 12.5) 17.6† (14.1 – 40.8) 56

60 years and older 13.3 (12.4 – 14.2) 9.42† (8.21 – 9.77) 13.3 (12.6 – 14.6) 18.0† (15.3 – 24.3) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.24.a.5. Plasma eicosenoic acid (20:1n-9): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 13.6 (13.1 – 14.2) 8.60 (7.88 – 9.22) 13.4 (12.9 – 13.8) 22.0 (20.7 – 23.3) 989

20–39 years 12.6 (11.8 – 13.6) 7.88 (6.83 – 8.26) 12.1 (11.4 – 13.0) 21.6 (19.4 – 24.2) 298

40–59 years 13.3 (12.7 – 13.9) 8.71 (7.53 – 9.56) 13.0 (11.9 – 13.7) 21.7 (19.0 – 23.1) 279

60 years and older 15.8 (15.2 – 16.3) 10.8 (10.4 – 11.1) 15.2 (14.7 – 15.9) 23.1 (21.7 – 25.4) 412

Males

Total, 20 years and older 13.9 (13.2 – 14.5) 8.91 (8.24 – 9.44) 13.6 (12.9 – 14.2) 22.2 (20.4 – 24.2) 472

20–39 years 12.5 (11.5 – 13.7) 7.92 (6.33 – 8.95) 11.9 (11.4 – 13.0) 18.2 (15.7 – 42.2) 128

40–59 years 13.9 (12.9 – 15.0) 8.97 (7.92 – 9.80) 13.8 (11.9 – 14.7) 22.2 (19.9 – 25.5) 140

60 years and older 15.8 (15.1 – 16.6) 10.6 (10.2 – 11.2) 15.3 (14.7 – 16.4) 23.4 (21.7 – 26.6) 204

Females

Total, 20 years and older 13.4 (12.8 – 14.1) 8.17 (7.57 – 9.08) 13.1 (12.6 – 13.7) 21.8 (20.5 – 23.4) 517

20–39 years 12.7 (11.7 – 13.8) 7.83 (5.75 – 8.15) 12.3 (10.7 – 13.7) 21.7 (20.6 – 25.6) 170

40–59 years 12.6 (11.9 – 13.4) 8.42 (6.89 – 9.47) 12.1 (11.7 – 13.0) 19.0 (17.2 – 22.9) 139

60 years and older 15.7 (14.9 – 16.5) 10.9 (10.5 – 11.4) 15.1 (14.5 – 15.9) 22.8 (21.2 – 26.1) 208
244

2nd 244 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.25.a.1. Plasma docosenoic acid (22:1n-9): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 3.44 (2.97 – 3.99) < LOD .712 (< LOD – 1.25) 3.62 (3.30 – 4.07) 10.3 (9.50 – 12.2) 13.6 (11.8 – 16.6) 1,604 Age group 20–39 years 3.36 (2.75 – 4.11) < LOD .612 (< LOD – 1.38) 3.46 (3.10 – 4.06) 11.6 (9.32 – 16.7) 14.7 (12.4 – 20.1) 533 40–59 years 3.39 (2.89 – 3.97) .310 (< LOD – .677) .729 (< LOD – 1.15) 3.51 (3.16 – 4.23) 9.45 (8.62 – 13.4) 12.6 (10.8 – 16.6) 454 60 years and older 3.67 (3.18 – 4.24) .421 (< LOD – .890) .831 (< LOD – 1.46) 3.93 (3.55 – 4.47) 9.69 (8.60 – 10.9) 11.2 (9.74 – 15.5) 617 Gender Males 3.34 (2.85 – 3.92) < LOD .620 (< LOD – 1.11) 3.54 (3.24 – 4.04) 10.1 (9.39 – 11.9) 12.9 (10.9 – 14.0) 767 Females 3.54 (3.04 – 4.12) .334 (< LOD – .936) .941 (< LOD – 1.41) 3.66 (3.33 – 4.23) 11.0 (8.65 – 14.7) 14.7 (11.9 – 17.7) 837 Race/ethnicity Mexican Americans 3.38 (2.83 – 4.03) < LOD† .692 (< LOD – 1.46) 3.69 (3.32 – 4.29) 10.5 (7.40 – 23.0) 13.3† (8.78 – 23.8) 345 Non-Hispanic Blacks 3.81 (3.39 – 4.29) .673† (< LOD – 1.47) 1.43 (< LOD – 1.72) 3.83 (3.46 – 4.50) 10.8 (9.41 – 15.0) 13.4† (11.0 – 20.1) 280 Non-Hispanic Whites 3.36 (2.79 – 4.05) < LOD .613 (< LOD – 1.15) 3.54 (3.16 – 4.23) 10.1 (9.13 – 12.6) 13.6 (11.4 – 16.8) 863 < LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

Plasma docosenoic acid

0 2 4 6 

(μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

6 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.25.a. Plasma docosenoic acid (22:1n–9): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma docosenoic acid Plasma docosenoic acid (μmol/L) (μmol/L) 0 2 4 6 0 2 4 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 245245
246 2nd 246 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.25.a.2. Plasma docosenoic acid (22:1n-9): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 3.44 (2.97 – 3.99) 1.38 (.670 – 1.82) 3.62 (3.30 – 4.07) 8.15 (7.41 – 9.51) 1,604

20–39 years 3.36 (2.75 – 4.11) 1.38 (< LOD – 1.87) 3.46 (3.10 – 4.06) 8.64 (7.27 – 11.3) 533

40–59 years 3.39 (2.89 – 3.97) 1.21 (.624 – 1.79) 3.51 (3.16 – 4.23) 8.03 (7.04 – 9.44) 454

60 years and older 3.67 (3.18 – 4.24) 1.55 (.813 – 1.94) 3.93 (3.55 – 4.47) 7.86 (7.43 – 8.68) 617

Males

Total, 20 years and older 3.34 (2.85 – 3.92) 1.22 (.372 – 1.85) 3.54 (3.24 – 4.04) 8.37 (7.59 – 9.60) 767

20–39 years 3.33 (2.63 – 4.20) 1.11 (< LOD – 1.89) 3.38 (2.94 – 4.18) 9.18 (7.58 – 12.3) 249

40–59 years 3.32 (2.85 – 3.86) 1.21 (.324 – 1.87) 3.68 (3.16 – 4.39) 8.06 (6.79 – 9.60) 219

60 years and older 3.42 (2.95 – 3.95) 1.33 (.641 – 1.75) 3.65 (3.35 – 3.95) 7.93 (7.45 – 9.69) 299

Females

Total, 20 years and older 3.54 (3.04 – 4.12) 1.47 (.937 – 1.84) 3.66 (3.33 – 4.23) 7.82 (7.24 – 9.41) 837

20–39 years 3.40 (2.83 – 4.08) 1.44 (.483 – 1.70) 3.58 (2.95 – 4.23) 7.58 (6.98 – 14.6) 284

40–59 years 3.46 (2.85 – 4.19) 1.16 (.666 – 1.76) 3.44 (3.03 – 4.43) 7.92 (7.18 – 11.5) 235

60 years and older 3.89 (3.33 – 4.54) 1.77 (.727 – 2.27) 4.25 (3.69 – 5.32) 7.69 (7.38 – 8.54) 318

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

Table 2.25.a.3. Plasma docosenoic acid (22:1n-9): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 3.38 (2.83 – 4.03) 1.47 (.698 – 1.86) 3.69 (3.32 – 4.29) 7.40 (6.31 – 12.3) 345

20–39 years 3.70 (2.96 – 4.62) 1.58 (< LOD – 2.35) 3.97 (3.54 – 4.50) 7.41 (6.18 – 16.2) 117

40–59 years 2.97 (2.04 – 4.31) 1.20† (< LOD – 1.85) 3.45 (2.09 – 4.69) 7.48† (5.26 – 12.2) 91

60 years and older 3.04 (2.44 – 3.79) 1.48 (< LOD – 1.90) 3.41 (2.89 – 3.83) 6.86 (5.67 – 12.0) 137

Males

Total, 20 years and older 3.57 (2.84 – 4.49) 1.51 (< LOD – 1.96) 3.93 (3.52 – 4.30) 8.15 (6.07 – 23.8) 170

20–39 years 3.72 (2.68 – 5.16) 1.38† (< LOD – 2.15) 4.00 (3.27 – 4.92) 7.88† (6.00 – 23.8) 58

40–59 years 3.47 (2.50 – 4.81) 1.47† (< LOD – 2.04) 3.82 (2.77 – 4.66) 8.18† (5.28 – 11.5) 47

60 years and older 3.00 (1.75 – 5.14) 1.47† (< LOD – 2.17) 3.41 (1.76 – 5.76) 7.10† (5.04 – 13.1) 65

Females

Total, 20 years and older 3.16 (2.54 – 3.92) 1.43 (< LOD – 1.87) 3.55 (2.85 – 4.70) 6.83 (5.85 – 7.88) 175

20–39 years 3.67 (3.03 – 4.43) 1.68† (< LOD – 2.49) 3.76 (3.30 – 4.88) 7.10† (5.69 – 18.2) 59

40–59 years 2.48 (1.54 – 3.98) .740† (< LOD – 1.71) 2.87 (1.88 – 4.31) 6.29† (4.79 – 12.2) 44

60 years and older 3.08 (2.53 – 3.75) 1.48† (< LOD – 2.10) 3.39 (2.65 – 3.84) 6.46† (4.82 – 10.8) 72

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 247247

Table 2.25.a.4. Plasma docosenoic acid (22:1n-9): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 3.81 (3.39 – 4.29) 1.76 (.712 – 2.22) 3.83 (3.46 – 4.50) 8.37 (7.02 – 13.4) 280

20–39 years 3.52 (2.85 – 4.34) 1.68 (< LOD – 2.11) 3.54 (3.15 – 4.17) 8.10 (5.61 – 23.4) 116

40–59 years 4.04 (3.53 – 4.64) 1.64† (< LOD – 2.46) 4.52 (3.73 – 5.02) 8.15† (7.20 – 11.6) 82

60 years and older 4.28 (3.65 – 5.01) 2.24† (.542 – 2.55) 4.19 (3.30 – 5.58) 8.49† (7.12 – 19.0) 82

Males

Total, 20 years and older 3.66 (3.11 – 4.30) 1.82 (< LOD – 2.26) 3.63 (3.08 – 4.53) 9.58 (7.05 – 13.4) 130

20–39 years 3.31 (2.46 – 4.44) 1.50† (< LOD – 2.27) 3.28 (2.35 – 4.53) 7.50† (5.46 – 23.8) 54

40–59 years 3.95 (3.14 – 4.96) 1.76† (< LOD – 2.60) 4.00 (3.07 – 5.03) 9.73† (6.86 – 14.6) 35

60 years and older 4.34 (3.73 – 5.05) 1.86† (< LOD – 2.52) 3.87 (3.28 – 6.41) 9.45† (8.02 – 19.0) 41

Females

Total, 20 years and older 3.94 (3.40 – 4.56) 1.75 (1.28 – 2.16) 4.14 (3.39 – 4.92) 8.10 (6.84 – 16.2) 150

20–39 years 3.70 (2.87 – 4.77) 1.68† (< LOD – 2.25) 3.57 (3.18 – 4.43) 8.27† (5.30 – 19.7) 62

40–59 years 4.12 (3.48 – 4.89) 1.57† (.381 – 2.46) 4.86 (3.40 – 6.24) 8.08† (6.93 – 11.9) 47

60 years and older 4.24 (3.22 – 5.58) 2.30† (1.77 – 2.61) 4.23 (2.58 – 6.59) 7.56† (6.37 – 11.8) 41

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.

Table 2.25.a.5. Plasma docosenoic acid (22:1n-9): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 3.36 (2.79 – 4.05) 1.18 (.420 – 1.78) 3.54 (3.16 – 4.23) 8.12 (7.40 – 9.59) 863

20–39 years 3.21 (2.41 – 4.27) 1.09 (< LOD – 1.87) 3.37 (2.71 – 4.30) 8.51 (7.27 – 11.9) 255

40–59 years 3.33 (2.77 – 4.01) 1.11 (.402 – 1.71) 3.44 (2.98 – 4.49) 8.10 (6.96 – 11.0) 242

60 years and older 3.63 (3.07 – 4.29) 1.49 (.647 – 1.90) 3.93 (3.52 – 4.55) 7.77 (7.44 – 8.50) 366

Males

Total, 20 years and older 3.21 (2.64 – 3.91) 1.09 (< LOD – 1.85) 3.48 (3.05 – 4.20) 8.14 (7.22 – 9.56) 412

20–39 years 3.10 (2.19 – 4.39) .749† (< LOD – 1.86) 3.20 (2.56 – 4.88) 8.97† (7.37 – 12.8) 110

40–59 years 3.21 (2.69 – 3.82) 1.08 (< LOD – 1.91) 3.52 (3.01 – 4.38) 7.62 (5.91 – 9.68) 122

60 years and older 3.38 (2.85 – 4.02) 1.37 (.534 – 1.82) 3.63 (3.33 – 4.15) 7.79 (6.98 – 9.24) 180

Females

Total, 20 years and older 3.51 (2.89 – 4.25) 1.36 (.604 – 1.76) 3.66 (3.21 – 4.30) 7.92 (7.38 – 10.4) 451

20–39 years 3.31 (2.57 – 4.24) 1.37 (< LOD – 1.89) 3.61 (2.73 – 4.30) 7.62 (6.64 – 16.9) 145

40–59 years 3.46 (2.74 – 4.36) 1.09 (.381 – 1.71) 3.43 (2.89 – 5.00) 8.43 (7.34 – 13.9) 120

60 years and older 3.85 (3.20 – 4.63) 1.54 (.484 – 2.18) 4.22 (3.61 – 5.48) 7.71 (7.39 – 8.61) 186

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.
248

2nd 248 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.26.a.1. Plasma nervonic acid (24:1n-9): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 74.9 (72.4 – 77.4) 45.6 (42.9 – 47.8) 49.8 (45.9 – 52.0) 75.0 (72.0 – 77.7) 116 (112 – 121) 126 (122 – 134) 1,696 Age group 20–39 years 72.2 (68.7 – 75.8) 44.5 (40.1 – 45.9) 47.8 (44.5 – 51.6) 72.1 (67.8 – 77.2) 109 (103 – 115) 118 (112 – 126) 573 40–59 years 74.3 (71.5 – 77.1) 46.4 (34.9 – 50.4) 51.2 (46.2 – 53.2) 74.1 (71.4 – 77.6) 109 (105 – 121) 123 (113 – 140) 492 60 years and older 81.0 (77.7 – 84.6) 44.1 (41.8 – 49.9) 50.7 (44.6 – 53.2) 79.9 (77.2 – 84.8) 128 (121 – 138) 137 (129 – 161) 631 Gender Males 72.0 (69.5 – 74.5) 44.3 (40.3 – 45.9) 47.0 (44.5 – 50.9) 71.9 (69.8 – 74.4) 109 (105 – 114) 118 (113 – 127) 816 Females 77.7 (74.8 – 80.7) 47.9 (44.6 – 50.0) 51.6 (47.0 – 55.3) 77.6 (74.3 – 80.0) 121 (116 – 126) 131 (124 – 141) 880 Race/ethnicity Mexican Americans 74.4 (71.0 – 78.0) 46.4† (32.6 – 52.8) 51.4 (43.8 – 54.3) 76.0 (71.1 – 77.9) 108 (101 – 121) 115† (108 – 157) 373 Non-Hispanic Blacks 77.3 (72.1 – 82.8) 44.4† (23.7 – 49.2) 49.3 (38.9 – 53.8) 77.5 (72.6 – 81.8) 123 (115 – 131) 129† (124 – 161) 288 Non-Hispanic Whites 74.1 (71.3 – 77.0) 45.0 (42.5 – 46.4) 49.2 (45.4 – 51.8) 74.0 (71.0 – 77.4) 117 (111 – 122) 127 (122 – 135) 914 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 50 100 150 

Plasma nervonic acid

(μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

150

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.26.a. Plasma nervonic acid (24:1n–9): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma nervonic acid Plasma nervonic acid (μmol/L) (μmol/L) 0 50 100 150 0 50 100 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 249249
250 2nd 250 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.26.a.2. Plasma nervonic acid (24:1n-9): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 74.9 (72.4 – 77.4) 54.4 (51.9 – 56.6) 75.0 (72.0 – 77.7) 103 (99.6 – 108) 1,696

20–39 years 72.2 (68.7 – 75.8) 53.0 (48.3 – 56.2) 72.1 (67.8 – 77.2) 97.3 (94.2 – 103) 573

40–59 years 74.3 (71.5 – 77.1) 55.0 (52.8 – 57.6) 74.1 (71.4 – 77.6) 98.7 (94.9 – 105) 492

60 years and older 81.0 (77.7 – 84.6) 55.9 (51.8 – 60.0) 79.9 (77.2 – 84.8) 118 (110 – 124) 631

Males

Total, 20 years and older 72.0 (69.5 – 74.5) 52.8 (49.8 – 54.8) 71.9 (69.8 – 74.4) 98.6 (95.6 – 102) 816

20–39 years 70.9 (67.0 – 75.0) 52.5 (46.1 – 55.4) 69.2 (64.8 – 76.3) 99.1 (94.0 – 106) 267

40–59 years 72.1 (69.4 – 74.9) 53.1 (47.3 – 57.2) 72.6 (71.1 – 74.6) 96.2 (88.9 – 104) 240

60 years and older 73.9 (70.9 – 77.0) 51.4 (46.3 – 55.2) 74.2 (71.1 – 78.3) 103 (98.0 – 112) 309

Females

Total, 20 years and older 77.7 (74.8 – 80.7) 56.9 (52.7 – 59.5) 77.6 (74.3 – 80.0) 107 (101 – 115) 880

20–39 years 73.4 (70.0 – 77.0) 53.9 (48.4 – 58.2) 74.9 (71.5 – 77.6) 96.9 (92.9 – 104) 306

40–59 years 76.4 (73.2 – 79.8) 57.4 (51.9 – 59.8) 76.8 (70.4 – 81.2) 101 (97.7 – 109) 252

60 years and older 87.3 (82.8 – 92.0) 62.0 (55.7 – 65.4) 86.3 (80.7 – 92.6) 123 (119 – 135) 322

Table 2.26.a.3. Plasma nervonic acid (24:1n-9): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 74.4 (71.0 – 78.0) 55.3 (50.7 – 58.6) 76.0 (71.1 – 77.9) 99.1 (93.7 – 107) 373

20–39 years 73.9 (69.6 – 78.6) 55.3 (43.9 – 58.9) 75.8 (70.4 – 77.8) 96.1 (93.3 – 108) 129

40–59 years 73.9 (69.3 – 78.6) 54.3† (46.6 – 58.8) 74.0 (69.0 – 81.3) 96.6† (89.4 – 122) 93

60 years and older 78.6 (74.8 – 82.7) 58.7 (50.2 – 62.1) 80.2 (76.6 – 82.5) 105 (98.7 – 115) 151

Males

Total, 20 years and older 74.2 (71.0 – 77.6) 55.5 (52.7 – 57.7) 73.5 (70.5 – 77.7) 99.6 (93.4 – 107) 187

20–39 years 74.0 (70.5 – 77.6) 54.5† (46.3 – 58.7) 72.2 (69.5 – 78.7) 94.9† (91.2 – 107) 65

40–59 years 74.1 (68.4 – 80.2) 55.7† (46.0 – 59.9) 70.1 (66.9 – 80.6) 102† (89.0 – 127) 48

60 years and older 76.6 (69.3 – 84.7) 53.2† (39.5 – 63.4) 78.0 (66.3 – 88.3) 104† (97.5 – 157) 74

Females

Total, 20 years and older 74.6 (69.7 – 79.9) 55.2 (45.9 – 59.3) 77.2 (67.2 – 82.0) 96.6 (90.8 – 116) 186

20–39 years 73.9 (67.3 – 81.2) 55.3† (43.1 – 59.1) 77.1 (63.6 – 79.7) 98.6† (89.2 – 129) 64

40–59 years 73.6 (67.1 – 80.8) 50.9† (44.5 – 59.4) 78.4 (63.4 – 85.5) 92.1† (86.2 – 121) 45

60 years and older 80.5 (74.5 – 87.0) 60.5† (32.6 – 67.0) 80.6 (73.5 – 88.3) 104† (92.5 – 159) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 251251

Table 2.26.a.4. Plasma nervonic acid (24:1n-9): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 77.3 (72.1 – 82.8) 54.4 (49.3 – 57.4) 77.5 (72.6 – 81.8) 110 (102 – 121) 288

20–39 years 73.1 (67.2 – 79.6) 50.9 (44.3 – 55.8) 74.1 (67.5 – 79.8) 101 (93.6 – 128) 116

40–59 years 79.9 (74.1 – 86.2) 56.3† (50.0 – 61.9) 78.7 (72.8 – 81.6) 112† (99.6 – 137) 93

60 years and older 84.1 (74.8 – 94.6) 55.3† (43.3 – 59.2) 87.7 (77.2 – 94.2) 122† (114 – 131) 79

Males

Total, 20 years and older 74.4 (67.7 – 81.8) 53.3 (45.2 – 55.5) 74.4 (67.4 – 81.1) 111 (97.0 – 128) 133

20–39 years 69.3 (58.5 – 82.0) 45.2† (23.7 – 53.9) 67.4 (60.3 – 80.6) 104† (81.7 – 129) 54

40–59 years 78.9 (72.2 – 86.3) 56.7† (53.9 – 66.2) 76.6 (68.8 – 81.4) 109† (94.2 – 133) 40

60 years and older 82.3 (73.6 – 92.0) 54.7† (49.6 – 62.2) 84.5 (59.7 – 104) 117† (104 – 129) 39

Females

Total, 20 years and older 79.6 (73.4 – 86.4) 55.7 (50.1 – 60.1) 79.3 (73.1 – 88.6) 109 (101 – 123) 155

20–39 years 76.6 (68.7 – 85.4) 55.6† (48.6 – 61.3) 75.4 (70.3 – 86.2) 98.9† (92.0 – 123) 62

40–59 years 80.6 (72.3 – 90.0) 55.5† (43.4 – 62.9) 79.2 (71.0 – 89.5) 112† (101 – 160) 53

60 years and older 85.3 (71.6 – 102) 51.8† (39.7 – 62.8) 89.2 (75.8 – 95.2) 123† (101 – 167) 40

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.26.a.5. Plasma nervonic acid (24:1n-9): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 74.1 (71.3 – 77.0) 53.5 (51.3 – 56.2) 74.0 (71.0 – 77.4) 102 (98.6 – 109) 914

20–39 years 70.5 (66.5 – 74.8) 51.9 (45.2 – 56.2) 70.7 (64.8 – 76.2) 94.0 (88.1 – 109) 281

40–59 years 73.2 (70.1 – 76.5) 53.9 (51.0 – 57.6) 73.6 (69.8 – 77.6) 97.6 (91.9 – 108) 265

60 years and older 81.0 (77.1 – 85.1) 55.4 (51.8 – 58.7) 79.9 (75.7 – 85.4) 118 (109 – 132) 368

Males

Total, 20 years and older 70.6 (68.1 – 73.1) 52.1 (48.1 – 54.1) 71.0 (68.4 – 73.4) 97.2 (90.7 – 101) 437

20–39 years 68.4 (64.3 – 72.7) 52.0 (43.7 – 55.7) 66.3 (61.7 – 73.0) 92.2 (84.4 – 109) 120

40–59 years 71.0 (67.8 – 74.5) 52.8 (46.3 – 54.4) 72.3 (70.9 – 74.2) 93.2 (86.4 – 107) 135

60 years and older 73.0 (70.0 – 76.1) 50.9 (43.5 – 54.8) 73.7 (68.5 – 78.8) 102 (93.9 – 113) 182

Females

Total, 20 years and older 77.5 (73.8 – 81.3) 56.2 (51.9 – 59.2) 77.4 (72.4 – 81.0) 108 (101 – 119) 477

20–39 years 72.5 (67.9 – 77.5) 51.9 (45.2 – 57.6) 74.1 (68.9 – 78.3) 96.1 (90.0 – 115) 161

40–59 years 75.5 (71.7 – 79.4) 57.2 (51.9 – 59.3) 74.7 (68.4 – 80.7) 100 (94.7 – 109) 130

60 years and older 88.4 (83.1 – 94.1) 61.8 (53.5 – 68.4) 88.3 (79.8 – 96.5) 126 (119 – 137) 186
252

2nd 252 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.27.a.1. Plasma linoleic acid (18:2n-6): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 3,450 (3,390 – 3,510) 2,210 (2,070 – 2,300) 2,370 (2,310 – 2,450) 3,430 (3,370 – 3,520) 4,980 (4,810 – 5,190) 5,410 (5,140 – 5,840) 1,806 Age group 20–39 years 3,340 (3,260 – 3,410) 2,150 (1,830 – 2,290) 2,340 (2,200 – 2,460) 3,310 (3,240 – 3,370) 4,810 (4,630 – 5,230) 5,250 (4,910 – 6,260) 610 40–59 years 3,520 (3,440 – 3,600) 2,230 (1,740 – 2,360) 2,420 (2,250 – 2,570) 3,500 (3,410 – 3,620) 5,060 (4,830 – 5,610) 5,550 (5,110 – 5,880) 515 60 years and older 3,520 (3,430 – 3,600) 2,250 (1,960 – 2,320) 2,360 (2,280 – 2,490) 3,570 (3,480 – 3,640) 5,090 (4,870 – 5,220) 5,440 (5,160 – 5,890) 681 Gender Males 3,380 (3,300 – 3,470) 2,240 (2,120 – 2,310) 2,340 (2,310 – 2,410) 3,360 (3,240 – 3,450) 4,900 (4,640 – 5,360) 5,240 (5,090 – 5,810) 863 Females 3,500 (3,430 – 3,580) 2,170 (1,910 – 2,340) 2,420 (2,300 – 2,540) 3,530 (3,450 – 3,600) 5,040 (4,880 – 5,280) 5,500 (5,100 – 5,900) 943 Race/ethnicity Mexican Americans 3,730 (3,570 – 3,900) 2,320† (1,840 – 2,480) 2,490 (2,330 – 2,610) 3,660 (3,510 – 3,900) 5,800 (5,270 – 6,570) 6,320† (5,810 – 7,000) 375 Non-Hispanic Blacks 3,210 (3,090 – 3,340) 2,140† (1,850 – 2,200) 2,250 (2,110 – 2,360) 3,130 (3,030 – 3,230) 4,610 (4,460 – 4,810) 4,960† (4,640 – 8,680) 310 Non-Hispanic Whites 3,440 (3,370 – 3,510) 2,210 (2,020 – 2,300) 2,360 (2,270 – 2,500) 3,440 (3,360 – 3,540) 4,950 (4,800 – 5,080) 5,190 (5,050 – 5,780) 991 † Estimate is subject to greater uncertainty due to small cell size.
20−39 40−59 60+ 

0 2000 4000 6000 

Plasma linoleic acid

(μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

6000

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.27.a. Plasma linoleic acid (18:2n–6): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma linoleic acid Plasma linoleic acid (μmol/L) (μmol/L) 0 2000 4000 6000 0 2000 4000 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 253253
254 2nd 254 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.27.a.2. Plasma linoleic acid (18:2n-6): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 3,450 (3,390 – 3,510) 2,610 (2,550 – 2,700) 3,430 (3,370 – 3,520) 4,570 (4,410 – 4,730) 1,806

20–39 years 3,340 (3,260 – 3,410) 2,570 (2,470 – 2,610) 3,310 (3,240 – 3,370) 4,410 (4,280 – 4,670) 610

40–59 years 3,520 (3,440 – 3,600) 2,700 (2,520 – 2,780) 3,500 (3,410 – 3,620) 4,700 (4,510 – 4,830) 515

60 years and older 3,520 (3,430 – 3,600) 2,690 (2,480 – 2,790) 3,570 (3,480 – 3,640) 4,580 (4,410 – 4,870) 681

Males

Total, 20 years and older 3,380 (3,300 – 3,470) 2,590 (2,480 – 2,680) 3,360 (3,240 – 3,450) 4,510 (4,240 – 4,720) 863

20–39 years 3,280 (3,190 – 3,380) 2,510 (2,420 – 2,600) 3,210 (3,150 – 3,320) 4,380 (4,030 – 4,910) 282

40–59 years 3,530 (3,430 – 3,620) 2,710 (2,600 – 2,790) 3,490 (3,350 – 3,640) 4,610 (4,350 – 4,860) 248

60 years and older 3,320 (3,220 – 3,420) 2,420 (2,320 – 2,570) 3,370 (3,180 – 3,510) 4,310 (4,160 – 4,680) 333

Females

Total, 20 years and older 3,500 (3,430 – 3,580) 2,640 (2,580 – 2,740) 3,530 (3,450 – 3,600) 4,660 (4,490 – 4,820) 943

20–39 years 3,390 (3,270 – 3,510) 2,590 (2,530 – 2,630) 3,390 (3,280 – 3,520) 4,420 (4,270 – 4,860) 328

40–59 years 3,510 (3,390 – 3,630) 2,630 (2,350 – 2,860) 3,530 (3,420 – 3,620) 4,790 (4,380 – 5,030) 267

60 years and older 3,690 (3,580 – 3,800) 2,870 (2,770 – 2,940) 3,700 (3,600 – 3,790) 4,820 (4,540 – 5,080) 348

Table 2.27.a.3. Plasma linoleic acid (18:2n-6): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 3,730 (3,570 – 3,900) 2,700 (2,500 – 2,900) 3,660 (3,510 – 3,900) 5,170 (4,740 – 5,900) 375

20–39 years 3,630 (3,350 – 3,920) 2,620 (2,350 – 2,730) 3,530 (3,280 – 3,960) 5,120 (4,570 – 6,320) 132

40–59 years 3,920 (3,720 – 4,130) 2,900† (2,410 – 3,150) 3,810 (3,690 – 4,100) 5,370† (4,730 – 7,050) 93

60 years and older 3,860 (3,540 – 4,210) 2,910 (2,120 – 3,360) 3,840 (3,530 – 4,250) 5,050 (4,590 – 6,170) 150

Males

Total, 20 years and older 3,700 (3,460 – 3,950) 2,630 (2,330 – 2,910) 3,640 (3,280 – 4,140) 5,100 (4,650 – 6,350) 188

20–39 years 3,600 (3,220 – 4,040) 2,490† (2,310 – 2,860) 3,500 (3,030 – 4,300) 5,020† (4,440 – 6,640) 67

40–59 years 3,890 (3,610 – 4,200) 3,010† (2,020 – 3,250) 3,860 (3,600 – 4,150) 5,050† (4,530 – 7,450) 48

60 years and older 3,750 (3,490 – 4,030) 2,750† (2,170 – 3,290) 3,760 (3,580 – 3,990) 4,960† (4,330 – 5,580) 73

Females

Total, 20 years and older 3,780 (3,610 – 3,960) 2,710 (2,260 – 3,040) 3,680 (3,530 – 3,920) 5,260 (4,810 – 5,960) 187

20–39 years 3,660 (3,320 – 4,030) 2,710† (1,840 – 3,050) 3,550 (3,470 – 3,910) 5,130† (4,350 – 6,500) 65

40–59 years 3,950 (3,680 – 4,250) 2,720† (2,350 – 3,130) 3,780 (3,580 – 4,330) 5,440† (4,800 – 6,970) 45

60 years and older 3,970 (3,440 – 4,580) 2,920† (2,120 – 3,520) 3,930 (3,450 – 4,570) 5,080† (4,570 – 6,220) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 255255

Table 2.27.a.4. Plasma linoleic acid (18:2n-6): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 3,210 (3,090 – 3,340) 2,430 (2,350 – 2,490) 3,130 (3,030 – 3,230) 4,250 (4,120 – 4,540) 310

20–39 years 3,140 (2,940 – 3,340) 2,360 (2,150 – 2,460) 3,050 (2,860 – 3,230) 4,200 (4,030 – 4,570) 126

40–59 years 3,280 (3,110 – 3,470) 2,540† (2,240 – 2,690) 3,160 (3,040 – 3,260) 4,330† (4,100 – 5,000) 98

60 years and older 3,290 (3,080 – 3,510) 2,470† (1,190 – 2,710) 3,410 (3,090 – 3,550) 4,210† (3,930 – 5,080) 86

Males

Total, 20 years and older 3,190 (3,070 – 3,320) 2,350 (2,180 – 2,480) 3,070 (2,980 – 3,190) 4,380 (3,940 – 4,840) 143

20–39 years 3,120 (2,900 – 3,350) 2,320† (1,800 – 2,450) 3,030 (2,790 – 3,290) 4,110† (3,750 – 7,040) 58

40–59 years 3,370 (3,190 – 3,570) 2,610† (2,200 – 2,750) 3,160 (2,990 – 3,280) 4,570† (4,110 – 8,980) 42

60 years and older 3,050 (2,750 – 3,380) 2,300† (1,190 – 2,500) 3,070 (2,730 – 3,650) 4,010† (3,800 – 4,250) 43

Females

Total, 20 years and older 3,230 (3,050 – 3,410) 2,460 (2,390 – 2,560) 3,180 (2,970 – 3,380) 4,210 (4,040 – 5,050) 167

20–39 years 3,160 (2,920 – 3,410) 2,410† (2,220 – 2,470) 3,100 (2,820 – 3,340) 4,230† (3,900 – 5,030) 68

40–59 years 3,220 (3,000 – 3,440) 2,490† (2,160 – 2,630) 3,100 (2,910 – 3,410) 4,120† (3,720 – 7,490) 56

60 years and older 3,450 (3,190 – 3,720) 2,640† (2,420 – 2,910) 3,430 (3,050 – 3,750) 4,350† (4,100 – 5,080) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.27.a.5. Plasma linoleic acid (18:2n-6): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 3,440 (3,370 – 3,510) 2,620 (2,530 – 2,710) 3,440 (3,360 – 3,540) 4,520 (4,340 – 4,720) 991

20–39 years 3,330 (3,250 – 3,420) 2,580 (2,520 – 2,620) 3,310 (3,250 – 3,380) 4,360 (4,130 – 4,730) 300

40–59 years 3,470 (3,370 – 3,580) 2,690 (2,360 – 2,830) 3,480 (3,340 – 3,620) 4,560 (4,300 – 4,820) 280

60 years and older 3,530 (3,430 – 3,630) 2,680 (2,420 – 2,800) 3,590 (3,490 – 3,690) 4,600 (4,440 – 4,930) 411

Males

Total, 20 years and older 3,360 (3,260 – 3,470) 2,580 (2,440 – 2,690) 3,370 (3,210 – 3,500) 4,330 (4,130 – 4,740) 471

20–39 years 3,250 (3,140 – 3,370) 2,530 (2,420 – 2,600) 3,210 (3,130 – 3,330) 4,150 (3,860 – 5,070) 128

40–59 years 3,480 (3,340 – 3,630) 2,710 (2,430 – 2,830) 3,480 (3,290 – 3,650) 4,430 (4,200 – 4,930) 140

60 years and older 3,330 (3,210 – 3,450) 2,420 (2,300 – 2,580) 3,370 (3,090 – 3,600) 4,320 (4,110 – 4,780) 203

Females

Total, 20 years and older 3,510 (3,430 – 3,590) 2,660 (2,570 – 2,770) 3,530 (3,420 – 3,610) 4,660 (4,480 – 4,820) 520

20–39 years 3,410 (3,240 – 3,580) 2,610 (2,430 – 2,740) 3,390 (3,250 – 3,580) 4,390 (4,180 – 4,970) 172

40–59 years 3,470 (3,330 – 3,610) 2,570 (2,220 – 2,870) 3,480 (3,340 – 3,610) 4,720 (4,290 – 4,940) 140

60 years and older 3,720 (3,580 – 3,860) 2,900 (2,810 – 2,970) 3,760 (3,640 – 3,840) 4,860 (4,530 – 5,140) 208
256

2nd 256 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.28.a.1. Plasma alpha-linolenic acid (18:3n-3): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 63.1 (60.5 – 65.8) 25.2 (21.4 – 27.5) 30.0 (26.0 – 33.1) 61.4 (58.9 – 63.7) 137 (128 – 151) 165 (153 – 192) 1,801 Age group 20–39 years 58.1 (55.8 – 60.6) 24.9 (19.9 – 26.6) 27.3 (25.2 – 30.3) 57.5 (55.2 – 59.9) 127 (117 – 150) 159 (137 – 221) 610 40–59 years 65.0 (60.7 – 69.6) 25.1 (14.3 – 30.3) 30.8 (22.7 – 35.6) 61.2 (58.2 – 66.9) 134 (127 – 162) 174 (157 – 203) 513 60 years and older 69.0 (65.2 – 73.0) 29.3 (20.8 – 33.2) 33.5 (28.4 – 36.4) 68.3 (64.9 – 72.3) 143 (138 – 154) 159 (147 – 234) 678 Gender Males 62.1 (58.8 – 65.5) 23.0 (17.0 – 26.2) 27.6 (22.4 – 31.7) 59.9 (57.3 – 64.2) 142 (128 – 172) 173 (155 – 210) 859 Females 64.1 (61.1 – 67.2) 27.2 (23.6 – 30.6) 32.8 (27.5 – 34.7) 62.4 (59.9 – 65.5) 131 (123 – 150) 158 (146 – 184) 942 Race/ethnicity Mexican Americans 69.0 (63.8 – 74.5) 23.9† (20.1 – 30.7) 31.8 (24.3 – 36.1) 66.2 (59.6 – 73.9) 160 (135 – 246) 199† (159 – 421) 375 Non-Hispanic Blacks 53.8 (50.4 – 57.4) 24.5† (13.3 – 28.8) 28.8 (23.7 – 30.8) 50.5 (48.2 – 53.1) 115 (107 – 147) 149† (121 – 362) 310 Non-Hispanic Whites 63.3 (59.9 – 66.8) 25.2 (20.0 – 27.5) 29.5 (25.8 – 33.0) 62.3 (58.9 – 65.7) 133 (124 – 153) 157 (143 – 193) 986 † Estimate is subject to greater uncertainty due to small cell size.
20−39 40−59 60+ 

0 50 100 150

Plasma alpha−linolenic acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

150

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.28.a. Plasma alpha−linolenic acid (18:3n–3): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma alpha−linolenic Plasma alpha−linolenic acid (μmol/L) acid (μmol/L) 0 50 100 150 0 50 100 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 257257
258 2nd 258 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.28.a.2. Plasma alpha-linolenic acid (18:3n-3): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample

10th 50th 90th size

Males and Females

Total, 20 years and older 63.1 (60.5 – 65.8) 35.3 (33.1 – 38.0) 61.4 (58.9 – 63.7) 114 (110 – 121) 1,801

20–39 years 58.1 (55.8 – 60.6) 32.9 (30.8 – 34.2) 57.5 (55.2 – 59.9) 107 (98.2 – 116) 610

40–59 years 65.0 (60.7 – 69.6) 37.6 (31.3 – 40.5) 61.2 (58.2 – 66.9) 117 (110 – 128) 513

60 years and older 69.0 (65.2 – 73.0) 39.3 (34.8 – 43.2) 68.3 (64.9 – 72.3) 123 (112 – 137) 678

Males

Total, 20 years and older 62.1 (58.8 – 65.5) 33.6 (28.6 – 37.0) 59.9 (57.3 – 64.2) 116 (110 – 127) 859

20–39 years 56.9 (53.5 – 60.6) 31.6 (27.5 – 34.3) 55.7 (51.2 – 59.6) 107 (98.1 – 121) 282

40–59 years 65.9 (61.5 – 70.6) 34.5 (23.9 – 43.7) 63.6 (58.1 – 72.9) 125 (112 – 132) 246

60 years and older 65.4 (60.1 – 71.2) 35.3 (31.7 – 39.8) 63.8 (57.2 – 73.8) 120 (107 – 147) 331

Females

Total, 20 years and older 64.1 (61.1 – 67.2) 38.1 (35.1 – 39.7) 62.4 (59.9 – 65.5) 113 (106 – 122) 942

20–39 years 59.3 (56.1 – 62.7) 34.0 (30.7 – 36.2) 59.1 (56.0 – 62.6) 105 (93.4 – 125) 328

40–59 years 64.2 (58.4 – 70.4) 38.5 (34.1 – 40.6) 58.8 (55.3 – 65.7) 112 (103 – 125) 267

60 years and older 72.0 (67.3 – 77.1) 42.9 (36.5 – 47.5) 71.1 (66.9 – 76.6) 123 (109 – 141) 347

Table 2.28.a.3. Plasma alpha-linolenic acid (18:3n-3): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 69.0 (63.8 – 74.5) 39.4 (30.2 – 43.0) 66.2 (59.6 – 73.9) 133 (117 – 159) 375

20–39 years 65.6 (56.2 – 76.6) 36.8 (25.2 – 41.3) 61.4 (54.6 – 73.8) 125 (111 – 215) 132

40–59 years 73.8 (65.4 – 83.2) 43.8† (30.1 – 47.8) 70.5 (59.0 – 88.4) 133† (115 – 146) 93

60 years and older 76.1 (65.5 – 88.5) 43.6 (34.4 – 47.4) 75.9 (67.6 – 82.9) 136 (108 – 292) 150

Males

Total, 20 years and older 68.9 (61.1 – 77.7) 40.5 (25.8 – 43.5) 65.9 (54.6 – 80.2) 134 (113 – 201) 188

20–39 years 66.2 (52.3 – 83.9) 39.3† (22.8 – 42.6) 58.5 (44.6 – 86.5) 130† (91.9 – 222) 67

40–59 years 74.4 (59.7 – 92.8) 43.7† (22.7 – 50.8) 70.4 (55.6 – 95.9) 133† (105 – 421) 48

60 years and older 70.6 (60.3 – 82.5) 39.6† (31.8 – 47.0) 69.6 (55.1 – 79.4) 125† (94.7 – 292) 73

Females

Total, 20 years and older 69.1 (62.1 – 76.8) 37.5 (23.1 – 44.8) 66.2 (60.2 – 73.2) 131 (118 – 147) 187

20–39 years 64.7 (51.4 – 81.5) 32.7† (20.1 – 43.7) 63.6 (55.0 – 73.4) 125† (102 – 278) 65

40–59 years 73.0 (63.4 – 84.1) 41.4† (23.1 – 52.1) 69.0 (54.1 – 87.9) 132† (110 – 194) 45

60 years and older 81.6 (64.4 – 103) 45.2† (32.3 – 58.1) 82.0 (64.8 – 94.8) 144† (111 – 197) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 259259

Table 2.28.a.4. Plasma alpha-linolenic acid (18:3n-3): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 53.8 (50.4 – 57.4) 31.8 (29.4 – 34.0) 50.5 (48.2 – 53.1) 91.7 (81.0 – 112) 310

20–39 years 50.4 (44.6 – 56.8) 30.7 (26.4 – 33.1) 48.1 (43.0 – 53.0) 76.8 (69.0 – 142) 126

40–59 years 56.2 (52.0 – 60.6) 32.8† (23.4 – 36.2) 51.5 (47.1 – 55.1) 99.0† (81.8 – 315) 98

60 years and older 59.4 (53.3 – 66.2) 35.9† (29.4 – 40.4) 60.0 (53.5 – 63.0) 92.9† (81.4 – 142) 86

Males

Total, 20 years and older 53.4 (48.6 – 58.7) 29.4 (24.1 – 32.4) 51.7 (44.9 – 55.3) 93.3 (78.9 – 149) 143

20–39 years 49.6 (41.2 – 59.8) 28.8† (13.3 – 33.5) 45.5 (42.4 – 57.9) 75.7† (65.3 – 523) 58

40–59 years 57.9 (49.9 – 67.2) 29.7† (18.1 – 35.2) 51.6 (40.9 – 63.7) 124† (97.4 – 284) 42

60 years and older 56.4 (48.8 – 65.1) 30.6† (25.3 – 39.9) 59.8 (46.2 – 72.5) 90.7† (79.0 – 105) 43

Females

Total, 20 years and older 54.1 (50.0 – 58.5) 34.4 (32.1 – 37.0) 50.3 (47.5 – 54.6) 88.9 (77.4 – 120) 167

20–39 years 51.0 (45.7 – 56.9) 32.7† (28.1 – 35.9) 48.2 (41.2 – 57.7) 80.1† (67.0 – 134) 68

40–59 years 54.9 (47.8 – 62.9) 35.2† (23.1 – 39.9) 51.2 (44.3 – 57.6) 84.7† (75.8 – 332) 56

60 years and older 61.4 (53.7 – 70.1) 38.8† (32.9 – 43.2) 59.2 (52.0 – 64.8) 101† (81.5 – 142) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.28.a.5. Plasma alpha-linolenic acid (18:3n-3): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 63.3 (59.9 – 66.8) 34.9 (32.3 – 38.0) 62.3 (58.9 – 65.7) 113 (109 – 120) 986

20–39 years 58.3 (55.5 – 61.3) 32.4 (30.2 – 34.1) 58.4 (56.4 – 61.9) 103 (93.8 – 116) 300

40–59 years 64.0 (57.9 – 70.7) 37.5 (28.1 – 40.8) 60.5 (57.3 – 68.0) 114 (108 – 123) 278

60 years and older 69.4 (65.1 – 74.0) 39.4 (34.3 – 44.1) 69.0 (65.1 – 72.7) 125 (111 – 140) 408

Males

Total, 20 years and older 61.8 (58.1 – 65.7) 33.0 (27.5 – 36.6) 60.6 (57.4 – 65.4) 113 (108 – 124) 467

20–39 years 55.7 (52.2 – 59.5) 30.6 (26.4 – 33.7) 55.1 (47.7 – 60.6) 103 (95.6 – 113) 128

40–59 years 64.8 (59.6 – 70.5) 33.7 (16.1 – 45.7) 63.6 (58.1 – 70.8) 116 (108 – 132) 138

60 years and older 65.8 (60.1 – 72.1) 36.0 (29.2 – 41.6) 63.8 (57.1 – 74.4) 118 (109 – 145) 201

Females

Total, 20 years and older 64.7 (61.0 – 68.5) 38.2 (34.6 – 40.0) 62.8 (59.8 – 67.0) 113 (106 – 121) 519

20–39 years 60.8 (56.7 – 65.1) 34.0 (30.4 – 37.3) 61.0 (56.4 – 66.1) 103 (88.8 – 128) 172

40–59 years 63.2 (55.2 – 72.3) 38.4 (33.6 – 40.7) 58.4 (52.1 – 68.1) 111 (102 – 120) 140

60 years and older 72.5 (67.0 – 78.5) 41.9 (34.7 – 48.1) 71.2 (67.3 – 76.6) 127 (108 – 154) 207
260

2nd 260 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.29.a.1. Plasma gamma-linolenic acid (18:3n-6): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 46.9 (45.0 – 49.0) 17.1 (13.7 – 19.1) 20.2 (19.0 – 22.0) 49.0 (46.4 – 51.5) 100 (94.2 – 106) 117 (107 – 127) 1,795 Age group 20–39 years 41.7 (39.4 – 44.1) 15.0 (12.6 – 17.7) 19.3 (15.1 – 21.2) 41.9 (38.7 – 46.5) 85.1 (79.1 – 105) 99.8 (86.2 – 140) 603 40–59 years 51.0 (48.4 – 53.8) 18.4 (15.0 – 19.4) 20.4 (18.3 – 24.0) 53.3 (50.1 – 56.4) 108 (96.5 – 118) 121 (113 – 129) 513 60 years and older 49.6 (45.9 – 53.6) 18.3 (14.4 – 20.3) 22.0 (20.3 – 23.6) 51.2 (46.1 – 57.0) 102 (97.4 – 119) 115 (104 – 142) 679 Gender Males 48.0 (45.5 – 50.6) 17.1 (13.1 – 20.3) 22.0 (18.7 – 23.5) 50.0 (48.0 – 52.4) 99.2 (90.5 – 120) 120 (105 – 129) 855 Females 46.0 (43.7 – 48.4) 16.8 (12.8 – 19.1) 19.5 (17.0 – 21.6) 47.2 (44.0 – 50.6) 100 (92.8 – 106) 110 (106 – 128) 940 Race/ethnicity Mexican Americans 41.8 (38.1 – 45.8) 12.6† (6.25 – 15.0) 15.1 (9.90 – 18.6) 43.1 (38.4 – 49.9) 94.0 (89.7 – 115) 116† (96.3 – 132) 375 Non-Hispanic Blacks 42.5 (40.4 – 44.7) 16.5† (14.9 – 18.3) 20.6 (15.8 – 23.1) 42.8 (40.0 – 46.4) 84.1 (76.7 – 112) 105† (86.7 – 138) 309 Non-Hispanic Whites 48.8 (46.1 – 51.6) 19.2 (13.9 – 21.3) 22.1 (19.7 – 23.8) 50.5 (47.5 – 53.2) 101 (93.4 – 108) 117 (105 – 128) 981 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

Plasma gamma−linolenic

0 20 40 60 80 

acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 2.29.a. Plasma gamma−linolenic acid (18:3n–6): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma gamma−linolenic Plasma gamma−linolenic acid (μmol/L) acid (μmol/L) 0 20 40 60 80 0 20 40 60 80

Non−Hispanic Blacks 

20−39 40−59 60+ 

Females 

20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

20−39 40−59 60+ 

Males 

20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 261261
262 2nd 262 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.29.a.2. Plasma gamma-linolenic acid (18:3n-6): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 46.9 (45.0 – 49.0) 24.4 (22.9 – 25.8) 49.0 (46.4 – 51.5) 85.7 (82.1 – 90.3) 1,795

20–39 years 41.7 (39.4 – 44.1) 22.5 (20.6 – 24.1) 41.9 (38.7 – 46.5) 75.2 (69.9 – 80.9) 603

40–59 years 51.0 (48.4 – 53.8) 25.7 (23.4 – 29.5) 53.3 (50.1 – 56.4) 90.5 (87.1 – 94.7) 513

60 years and older 49.6 (45.9 – 53.6) 26.7 (23.9 – 29.1) 51.2 (46.1 – 57.0) 90.8 (82.8 – 101) 679

Males

Total, 20 years and older 48.0 (45.5 – 50.6) 25.6 (23.8 – 27.0) 50.0 (48.0 – 52.4) 85.7 (81.2 – 94.4) 855

20–39 years 45.7 (42.7 – 48.8) 25.1 (21.7 – 26.9) 48.8 (44.3 – 52.1) 79.5 (68.4 – 90.5) 277

40–59 years 52.7 (49.5 – 56.2) 26.3 (23.9 – 30.8) 55.7 (51.5 – 59.2) 91.9 (85.6 – 110) 246

60 years and older 44.3 (40.3 – 48.7) 24.7 (19.5 – 27.7) 44.5 (42.4 – 48.4) 79.8 (70.5 – 101) 332

Females

Total, 20 years and older 46.0 (43.7 – 48.4) 23.0 (21.5 – 24.8) 47.2 (44.0 – 50.6) 85.1 (80.4 – 89.8) 940

20–39 years 38.2 (35.3 – 41.3) 21.5 (16.6 – 23.1) 37.3 (34.7 – 41.3) 73.0 (62.6 – 79.0) 326

40–59 years 49.5 (46.3 – 53.0) 24.5 (20.1 – 27.8) 51.7 (48.2 – 55.8) 89.7 (81.9 – 101) 267

60 years and older 54.4 (50.0 – 59.2) 29.1 (26.2 – 30.6) 57.9 (50.7 – 64.5) 97.2 (88.0 – 105) 347

Table 2.29.a.3. Plasma gamma-linolenic acid (18:3n-6): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 41.8 (38.1 – 45.8) 19.5 (15.2 – 22.8) 43.1 (38.4 – 49.9) 83.5 (77.3 – 89.8) 375

20–39 years 38.5 (33.2 – 44.5) 18.1 (13.0 – 20.2) 40.4 (32.6 – 51.1) 71.2 (67.0 – 87.0) 132

40–59 years 47.4 (42.9 – 52.3) 24.2† (17.3 – 27.6) 48.3 (39.6 – 55.1) 94.9† (81.5 – 123) 93

60 years and older 46.9 (40.9 – 53.7) 24.0 (13.3 – 29.1) 48.7 (41.9 – 61.0) 86.0 (79.1 – 89.7) 150

Males

Total, 20 years and older 44.2 (38.1 – 51.2) 20.6 (14.5 – 26.3) 45.9 (38.4 – 54.8) 87.3 (74.0 – 91.6) 188

20–39 years 43.3 (34.6 – 54.2) 20.1† (7.22 – 25.2) 46.7 (32.8 – 60.0) 81.3† (67.1 – 107) 67

40–59 years 47.1 (37.9 – 58.6) 25.8† (9.42 – 31.7) 44.7 (38.0 – 55.2) 94.2† (70.9 – 155) 48

60 years and older 41.1 (33.5 – 50.5) 21.3† (11.1 – 25.6) 42.9 (26.9 – 60.8) 71.0† (57.5 – 131) 73

Females

Total, 20 years and older 39.0 (34.4 – 44.1) 16.5 (10.6 – 21.9) 40.1 (33.0 – 50.6) 82.4 (72.2 – 90.6) 187

20–39 years 32.8 (26.5 – 40.6) 14.7† (6.25 – 19.3) 34.6 (29.0 – 41.4) 61.6† (50.6 – 89.6) 65

40–59 years 47.6 (41.4 – 54.8) 21.0† (15.0 – 27.4) 51.3 (35.0 – 61.6) 94.9† (81.2 – 108) 45

60 years and older 52.9 (46.0 – 60.7) 26.6† (9.56 – 39.1) 55.3 (50.3 – 62.2) 88.9† (86.4 – 98.2) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 263263

Table 2.29.a.4. Plasma gamma-linolenic acid (18:3n-6): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 42.5 (40.4 – 44.7) 23.7 (22.0 – 25.1) 42.8 (40.0 – 46.4) 73.7 (68.3 – 80.0) 309

20–39 years 38.0 (35.1 – 41.2) 22.1 (18.2 – 24.1) 37.1 (32.7 – 41.8) 67.3 (61.8 – 76.2) 125

40–59 years 49.2 (45.5 – 53.2) 27.0† (19.9 – 33.0) 50.1 (48.6 – 53.3) 82.2† (73.0 – 111) 98

60 years and older 42.9 (40.1 – 45.9) 25.3† (11.9 – 30.0) 45.8 (39.8 – 48.6) 68.5† (66.3 – 74.0) 86

Males

Total, 20 years and older 44.7 (41.2 – 48.4) 24.8 (22.5 – 27.5) 44.2 (38.7 – 51.2) 75.4 (72.8 – 88.6) 142

20–39 years 41.7 (37.3 – 46.6) 23.4† (14.7 – 26.3) 42.5 (32.5 – 52.0) 73.1† (60.3 – 181) 57

40–59 years 51.1 (45.1 – 57.8) 27.9† (23.2 – 34.8) 48.8 (39.2 – 58.8) 88.5† (73.1 – 121) 42

60 years and older 40.9 (35.6 – 46.9) 23.6† (20.0 – 26.3) 39.8 (33.3 – 51.3) 69.4† (57.4 – 83.1) 43

Females

Total, 20 years and older 40.9 (38.9 – 43.0) 22.4 (18.9 – 25.2) 41.7 (37.8 – 46.2) 69.3 (65.9 – 78.6) 167

20–39 years 35.3 (32.6 – 38.2) 21.2† (15.5 – 24.3) 36.7 (29.9 – 39.1) 60.0† (50.6 – 82.2) 68

40–59 years 47.9 (42.3 – 54.2) 21.8† (17.8 – 33.3) 50.8 (46.4 – 54.0) 78.1† (68.2 – 109) 56

60 years and older 44.2 (39.6 – 49.4) 25.4† (11.9 – 31.0) 46.8 (36.5 – 54.0) 68.3† (61.7 – 78.4) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.29.a.5. Plasma gamma-linolenic acid (18:3n-6): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 48.8 (46.1 – 51.6) 25.6 (23.9 – 27.8) 50.5 (47.5 – 53.2) 86.9 (82.2 – 93.2) 981

20–39 years 44.1 (40.9 – 47.6) 24.0 (21.8 – 26.7) 45.3 (39.0 – 50.9) 76.3 (69.5 – 84.7) 294

40–59 years 51.9 (48.1 – 56.0) 26.6 (22.8 – 32.2) 54.2 (50.0 – 58.7) 90.3 (86.4 – 94.7) 278

60 years and older 50.6 (46.1 – 55.5) 26.8 (22.8 – 29.6) 52.4 (46.2 – 58.7) 92.5 (83.2 – 104) 409

Males

Total, 20 years and older 49.6 (46.0 – 53.4) 26.3 (23.9 – 29.6) 51.4 (49.0 – 53.5) 86.1 (79.7 – 101) 464

20–39 years 47.7 (43.6 – 52.1) 26.3 (22.5 – 29.5) 49.8 (46.8 – 52.9) 80.5 (67.7 – 115) 124

40–59 years 54.4 (50.0 – 59.2) 28.5 (24.0 – 33.3) 56.9 (51.7 – 60.7) 92.4 (85.5 – 117) 138

60 years and older 44.7 (39.8 – 50.3) 24.6 (16.3 – 28.7) 44.6 (41.8 – 49.7) 80.9 (67.4 – 119) 202

Females

Total, 20 years and older 48.1 (45.4 – 50.9) 24.6 (22.4 – 27.7) 49.1 (45.1 – 53.5) 87.3 (82.1 – 92.2) 517

20–39 years 41.3 (37.2 – 45.8) 23.0 (20.1 – 25.2) 39.6 (35.8 – 45.4) 75.5 (64.7 – 81.7) 170

40–59 years 49.5 (44.8 – 54.8) 25.4 (19.2 – 31.5) 50.5 (46.2 – 56.1) 88.9 (77.0 – 103) 140

60 years and older 56.1 (50.6 – 62.2) 29.6 (22.8 – 33.5) 60.6 (52.8 – 66.0) 97.4 (88.3 – 107) 207
264

2nd 264 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.30.a.1. Plasma eicosadienoic acid (20:2n-6): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 21.2 (20.7 – 21.8) 11.2 (10.5 – 11.6) 12.4 (11.9 – 12.8) 20.9 (20.3 – 21.6) 36.9 (35.1 – 39.9) 42.2 (39.9 – 47.3) 1,805 Age group 20–39 years 20.2 (19.5 – 20.9) 10.4 (9.44 – 11.0) 11.3 (10.7 – 12.0) 19.4 (18.6 – 20.3) 38.5 (35.8 – 43.2) 43.9 (40.7 – 50.1) 607 40–59 years 21.5 (20.6 – 22.3) 11.7 (10.3 – 12.2) 12.8 (11.8 – 13.7) 21.2 (20.3 – 22.4) 35.4 (33.9 – 40.3) 42.0 (38.1 – 47.5) 515 60 years and older 22.8 (22.1 – 23.5) 12.9 (10.6 – 14.0) 14.3 (13.1 – 15.3) 23.1 (22.3 – 23.6) 35.4 (33.7 – 37.4) 38.6 (36.6 – 46.6) 683 Gender Males 20.4 (19.7 – 21.2) 11.4 (10.6 – 11.9) 12.6 (11.8 – 13.0) 20.2 (19.3 – 21.1) 32.9 (31.3 – 37.1) 40.0 (35.1 – 44.9) 865 Females 22.0 (21.3 – 22.7) 11.0 (10.4 – 11.4) 12.2 (11.4 – 13.0) 21.7 (21.0 – 22.3) 38.5 (36.4 – 43.8) 46.5 (40.9 – 49.6) 940 Race/ethnicity Mexican Americans 25.2 (23.5 – 27.1) 11.4† (8.60 – 13.3) 13.3 (11.3 – 14.4) 24.9 (22.8 – 26.6) 49.5 (43.2 – 69.3) 55.0† (49.5 – 121) 375 Non-Hispanic Blacks 19.2 (18.3 – 20.1) 10.8† (9.00 – 11.2) 11.4 (10.5 – 12.5) 19.0 (18.1 – 19.7) 33.5 (28.4 – 40.5) 36.3† (34.6 – 51.6) 310 Non-Hispanic Whites 20.9 (20.3 – 21.5) 11.2 (9.83 – 11.8) 12.3 (11.7 – 12.9) 20.7 (20.1 – 21.4) 35.0 (33.5 – 38.1) 40.7 (36.9 – 46.5) 990 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 10 20 30 40 

Plasma eicosadienoic

acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

40

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.30.a. Plasma eicosadienoic acid (20:2n–6): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma eicosadienoic Plasma eicosadienoic acid (μmol/L) acid (μmol/L) 0 10 20 30 40 0 10 20 30 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 265265
266 2nd 266 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.30.a.2. Plasma eicosadienoic acid (20:2n-6): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 21.2 (20.7 – 21.8) 14.1 (13.5 – 14.6) 20.9 (20.3 – 21.6) 32.0 (30.8 – 33.8) 1,805

20–39 years 20.2 (19.5 – 20.9) 13.0 (12.0 – 13.7) 19.4 (18.6 – 20.3) 33.1 (30.9 – 36.6) 607

40–59 years 21.5 (20.6 – 22.3) 14.5 (13.2 – 15.3) 21.2 (20.3 – 22.4) 30.8 (30.0 – 33.7) 515

60 years and older 22.8 (22.1 – 23.5) 16.2 (15.2 – 16.8) 23.1 (22.3 – 23.6) 32.2 (31.0 – 33.4) 683

Males

Total, 20 years and older 20.4 (19.7 – 21.2) 13.9 (13.0 – 14.7) 20.2 (19.3 – 21.1) 29.6 (28.1 – 31.3) 865

20–39 years 19.3 (18.4 – 20.2) 13.1 (11.6 – 13.9) 19.2 (18.1 – 19.9) 28.3 (26.4 – 31.4) 282

40–59 years 21.2 (20.3 – 22.2) 14.5 (12.9 – 15.3) 20.9 (19.6 – 22.8) 30.3 (28.1 – 32.4) 248

60 years and older 21.4 (20.6 – 22.2) 15.3 (13.2 – 16.6) 21.0 (20.3 – 21.9) 29.5 (28.1 – 33.4) 335

Females

Total, 20 years and older 22.0 (21.3 – 22.7) 14.4 (13.7 – 14.8) 21.7 (21.0 – 22.3) 34.2 (32.5 – 36.2) 940

20–39 years 21.1 (20.1 – 22.3) 12.9 (12.2 – 13.8) 20.0 (19.0 – 21.2) 36.3 (34.3 – 39.4) 325

40–59 years 21.7 (20.6 – 22.9) 14.6 (12.2 – 15.7) 21.4 (20.5 – 22.2) 31.5 (29.9 – 37.8) 267

60 years and older 24.0 (23.1 – 24.9) 16.7 (15.6 – 17.7) 24.0 (23.1 – 25.4) 33.5 (32.4 – 35.7) 348

Table 2.30.a.3. Plasma eicosadienoic acid (20:2n-6): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 25.2 (23.5 – 27.1) 15.7 (13.4 – 17.2) 24.9 (22.8 – 26.6) 42.1 (35.6 – 51.2) 375

20–39 years 24.3 (21.7 – 27.3) 14.1 (12.6 – 16.7) 23.5 (20.5 – 27.8) 43.9 (33.7 – 55.6) 131

40–59 years 26.6 (24.6 – 28.8) 17.7† (12.3 – 20.2) 25.5 (24.5 – 26.5) 42.3† (35.8 – 73.3) 93

60 years and older 26.8 (25.4 – 28.3) 19.9 (18.1 – 20.4) 26.4 (24.7 – 27.6) 37.0 (35.1 – 49.3) 151

Males

Total, 20 years and older 24.7 (22.2 – 27.5) 14.9 (13.0 – 17.2) 24.7 (22.4 – 26.6) 39.9 (31.9 – 63.7) 189

20–39 years 23.8 (20.1 – 28.2) 13.7† (12.1 – 15.9) 23.9 (19.8 – 28.8) 36.5† (28.8 – 56.4) 67

40–59 years 26.4 (24.2 – 28.9) 17.6† (12.5 – 20.6) 25.2 (23.8 – 26.9) 41.6† (34.7 – 73.3) 48

60 years and older 25.8 (23.6 – 28.2) 18.7† (10.7 – 20.5) 25.6 (22.1 – 27.9) 37.0† (31.3 – 69.2) 74

Females

Total, 20 years and older 25.9 (24.0 – 28.0) 16.7 (11.4 – 17.4) 25.1 (22.2 – 27.7) 45.8 (37.6 – 55.9) 186

20–39 years 25.1 (21.8 – 28.8) 14.5† (10.8 – 17.2) 22.7 (20.1 – 27.0) 48.8† (37.2 – 56.6) 64

40–59 years 26.8 (23.1 – 31.2) 18.3† (8.60 – 20.6) 25.7 (23.0 – 28.3) 42.2† (32.9 – 58.3) 45

60 years and older 27.8 (24.0 – 32.2) 20.2† (17.8 – 20.8) 26.9 (22.9 – 34.5) 36.1† (34.7 – 51.5) 77

† Estimate is subject to greater uncertainty due to small cell size.
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 267267

Table 2.30.a.4. Plasma eicosadienoic acid (20:2n-6): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 19.2 (18.3 – 20.1) 12.8 (11.3 – 13.7) 19.0 (18.1 – 19.7) 27.8 (25.4 – 33.8) 310

20–39 years 18.3 (17.0 – 19.7) 12.2 (10.9 – 13.1) 17.9 (16.3 – 19.1) 26.4 (24.5 – 36.1) 126

40–59 years 19.8 (18.6 – 21.1) 13.3† (10.5 – 14.9) 19.2 (17.8 – 21.1) 28.1† (26.1 – 34.9) 98

60 years and older 20.5 (19.6 – 21.3) 14.2† (12.6 – 15.4) 21.1 (19.7 – 22.4) 27.5† (25.3 – 28.2) 86

Males

Total, 20 years and older 18.4 (17.3 – 19.5) 12.3 (10.9 – 13.3) 17.9 (16.5 – 19.2) 26.4 (24.3 – 31.6) 143

20–39 years 17.2 (16.4 – 18.1) 11.3† (9.43 – 13.2) 16.4 (16.0 – 18.2) 25.1† (22.0 – 48.7) 58

40–59 years 20.0 (17.8 – 22.3) 13.8† (10.2 – 15.5) 18.2 (16.8 – 20.4) 31.9† (26.2 – 52.2) 42

60 years and older 18.9 (16.7 – 21.3) 12.4† (8.53 – 14.5) 19.6 (17.1 – 21.5) 25.6† (23.5 – 35.0) 43

Females

Total, 20 years and older 19.8 (18.3 – 21.5) 12.9 (11.2 – 14.7) 19.4 (18.3 – 21.6) 28.2 (24.8 – 40.6) 167

20–39 years 19.3 (17.1 – 21.8) 12.5† (11.2 – 14.1) 18.5 (16.8 – 20.1) 32.1† (24.5 – 47.8) 68

40–59 years 19.7 (18.0 – 21.5) 12.9† (8.30 – 15.4) 19.3 (17.5 – 22.1) 27.0† (23.6 – 96.5) 56

60 years and older 21.5 (20.1 – 23.1) 15.9† (13.1 – 17.7) 21.9 (19.9 – 23.2) 27.7† (24.3 – 40.5) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.30.a.5. Plasma eicosadienoic acid (20:2n-6): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 20.9 (20.3 – 21.5) 14.0 (13.1 – 14.7) 20.7 (20.1 – 21.4) 31.0 (29.8 – 33.3) 990

20–39 years 19.7 (18.9 – 20.5) 12.8 (11.7 – 13.6) 19.3 (18.1 – 20.0) 33.1 (29.5 – 37.1) 298

40–59 years 20.8 (19.7 – 21.9) 13.9 (12.7 – 15.1) 20.8 (19.8 – 21.8) 30.2 (28.0 – 32.2) 280

60 years and older 22.7 (21.9 – 23.5) 16.0 (14.5 – 16.8) 23.0 (22.0 – 23.8) 31.9 (29.9 – 33.5) 412

Males

Total, 20 years and older 20.0 (19.3 – 20.7) 13.7 (12.8 – 14.8) 19.9 (18.9 – 20.8) 28.2 (27.1 – 30.4) 472

20–39 years 18.4 (17.4 – 19.5) 12.7 (10.9 – 13.9) 18.3 (17.3 – 19.4) 25.7 (23.3 – 29.6) 128

40–59 years 20.5 (19.4 – 21.6) 14.1 (12.8 – 15.1) 20.4 (18.7 – 22.5) 28.2 (27.3 – 30.6) 140

60 years and older 21.3 (20.4 – 22.2) 15.4 (12.9 – 16.7) 21.0 (20.1 – 22.1) 29.4 (28.0 – 33.4) 204

Females

Total, 20 years and older 21.8 (20.9 – 22.7) 14.3 (13.2 – 14.8) 21.5 (20.9 – 22.2) 33.8 (31.8 – 36.2) 518

20–39 years 20.9 (19.5 – 22.5) 12.8 (12.0 – 13.7) 20.0 (18.5 – 21.4) 36.9 (34.1 – 40.4) 170

40–59 years 21.1 (19.7 – 22.7) 13.8 (11.8 – 15.4) 21.1 (20.2 – 22.0) 30.9 (28.2 – 36.5) 140

60 years and older 23.9 (22.8 – 25.1) 16.5 (15.0 – 18.1) 24.1 (23.0 – 25.5) 33.2 (32.2 – 35.2) 208
268

2nd 268 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.31.a.1. Plasma homo-gamma-linolenic acid (20:3n-6): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 151 (147 – 156) 73.2 (67.9 – 79.6) 87.5 (84.6 – 89.9) 151 (145 – 156) 262 (254 – 274) 289 (281 – 320) 1,806 Age group 20–39 years 145 (140 – 149) 71.5 (57.7 – 78.3) 84.9 (75.9 – 91.3) 139 (135 – 146) 251 (239 – 276) 281 (262 – 317) 609 40–59 years 155 (147 – 163) 72.0 (67.7 – 86.3) 88.3 (83.1 – 94.0) 156 (147 – 164) 265 (258 – 286) 312 (284 – 337) 514 60 years and older 156 (148 – 164) 77.0 (62.8 – 84.0) 86.6 (77.7 – 92.8) 158 (148 – 167) 262 (254 – 285) 288 (275 – 357) 683 Gender Males 145 (139 – 153) 72.8 (62.2 – 76.4) 86.1 (76.4 – 90.0) 144 (135 – 153) 252 (237 – 277) 281 (260 – 373) 864 Females 157 (152 – 162) 72.9 (67.9 – 84.9) 88.5 (84.7 – 93.0) 156 (150 – 163) 272 (261 – 287) 304 (287 – 321) 942 Race/ethnicity Mexican Americans 166 (154 – 179) 82.2† (58.9 – 89.6) 92.0 (77.8 – 101) 167 (153 – 180) 297 (260 – 363) 330† (295 – 716) 375 Non-Hispanic Blacks 131 (128 – 135) 70.0† (52.8 – 75.7) 76.7 (70.3 – 85.5) 131 (127 – 136) 203 (196 – 230) 223† (206 – 276) 310 Non-Hispanic Whites 152 (146 – 159) 76.0 (67.7 – 84.6) 88.9 (84.9 – 92.9) 152 (144 – 157) 261 (250 – 281) 287 (275 – 324) 991 † Estimate is subject to greater uncertainty due to small cell size.
20−39 40−59 60+ 

0 100 200 300

Plasma homo−gamma−linolenic acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 2.31.a. Plasma homo−gamma−linolenic acid (20:3n–6): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma homo−gamma−linolenic Plasma homo−gamma−linolenic acid (μmol/L) acid (μmol/L) 0 100 200 300 0 100 200 300

Non−Hispanic Blacks 

20−39 40−59 60+ 

Females 

20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

20−39 40−59 60+ 

Males 

20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 269269
270 2nd 270 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.31.a.2. Plasma homo-gamma-linolenic acid (20:3n-6): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 151 (147 – 156) 98.4 (95.2 – 102) 151 (145 – 156) 232 (221 – 245) 1,806

20–39 years 145 (140 – 149) 95.6 (92.4 – 99.4) 139 (135 – 146) 223 (213 – 239) 609

40–59 years 155 (147 – 163) 102 (94.2 – 107) 156 (147 – 164) 240 (222 – 258) 514

60 years and older 156 (148 – 164) 100 (94.3 – 104) 158 (148 – 167) 236 (222 – 250) 683

Males

Total, 20 years and older 145 (139 – 153) 96.7 (93.1 – 100) 144 (135 – 153) 222 (210 – 246) 864

20–39 years 141 (134 – 149) 95.2 (88.2 – 97.7) 137 (131 – 145) 219 (201 – 247) 282

40–59 years 153 (144 – 163) 101 (93.8 – 107) 155 (141 – 161) 232 (217 – 272) 247

60 years and older 140 (131 – 150) 92.2 (84.0 – 97.9) 141 (133 – 153) 203 (185 – 244) 335

Females

Total, 20 years and older 157 (152 – 162) 102 (96.6 – 105) 156 (150 – 163) 241 (227 – 258) 942

20–39 years 148 (142 – 154) 97.3 (91.9 – 103) 142 (135 – 156) 226 (209 – 270) 327

40–59 years 157 (148 – 167) 104 (93.3 – 107) 157 (151 – 166) 241 (214 – 264) 267

60 years and older 170 (162 – 178) 107 (98.4 – 115) 175 (159 – 185) 258 (236 – 274) 348

Table 2.31.a.3. Plasma homo-gamma-linolenic acid (20:3n-6): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 166 (154 – 179) 103 (90.3 – 109) 167 (153 – 180) 258 (245 – 293) 375

20–39 years 158 (140 – 177) 96.7 (82.8 – 104) 158 (131 – 189) 254 (239 – 295) 131

40–59 years 178 (166 – 192) 110† (81.4 – 129) 178 (168 – 186) 289† (241 – 360) 93

60 years and older 177 (169 – 185) 119 (108 – 130) 185 (169 – 199) 245 (237 – 261) 151

Males

Total, 20 years and older 161 (143 – 181) 103 (85.0 – 114) 161 (138 – 192) 246 (222 – 296) 189

20–39 years 157 (133 – 185) 102† (65.4 – 113) 148 (121 – 204) 248† (215 – 329) 67

40–59 years 171 (149 – 196) 111† (84.1 – 132) 168 (148 – 194) 244† (213 – 361) 48

60 years and older 160 (146 – 176) 113† (49.9 – 123) 165 (143 – 181) 228† (188 – 288) 74

Females

Total, 20 years and older 172 (155 – 190) 93.0 (65.6 – 109) 175 (159 – 201) 272 (240 – 716) 186

20–39 years 159 (135 – 188) 89.4† (55.8 – 103) 160 (127 – 200) 269† (225 – 716) 64

40–59 years 188 (162 – 217) 106† (65.9 – 149) 190 (171 – 214) 303† (244 – 372) 45

60 years and older 194 (183 – 207) 128† (117 – 135) 204 (193 – 214) 258† (238 – 328) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 271271

Table 2.31.a.4. Plasma homo-gamma-linolenic acid (20:3n-6): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 131 (128 – 135) 91.5 (81.3 – 96.1) 131 (127 – 136) 187 (181 – 200) 310

20–39 years 129 (122 – 136) 88.0 (72.5 – 96.0) 128 (117 – 139) 186 (172 – 206) 126

40–59 years 136 (130 – 143) 98.8† (63.0 – 109) 134 (128 – 141) 198† (182 – 235) 98

60 years and older 130 (123 – 136) 85.9† (75.4 – 92.8) 134 (117 – 147) 183† (173 – 215) 86

Males

Total, 20 years and older 125 (119 – 131) 82.5 (73.7 – 94.9) 121 (112 – 130) 188 (173 – 203) 143

20–39 years 119 (111 – 128) 77.7† (53.1 – 94.7) 115 (106 – 130) 174† (168 – 196) 58

40–59 years 136 (129 – 144) 99.7† (71.4 – 105) 128 (118 – 147) 197† (174 – 261) 42

60 years and older 120 (107 – 134) 76.3† (45.9 – 90.2) 118 (105 – 141) 184† (156 – 213) 43

Females

Total, 20 years and older 136 (129 – 144) 93.0 (85.4 – 103) 135 (124 – 150) 186 (180 – 206) 167

20–39 years 137 (125 – 149) 92.6† (77.6 – 104) 134 (116 – 159) 193† (174 – 272) 68

40–59 years 136 (126 – 147) 94.2† (49.0 – 116) 135 (128 – 145) 189† (156 – 298) 56

60 years and older 136 (124 – 149) 92.6† (70.7 – 102) 144 (115 – 160) 182† (171 – 216) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.31.a.5. Plasma homo-gamma-linolenic acid (20:3n-6): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 152 (146 – 159) 99.3 (94.2 – 103) 152 (144 – 157) 233 (218 – 250) 991

20–39 years 147 (140 – 154) 97.2 (91.2 – 103) 140 (135 – 148) 226 (215 – 245) 300

40–59 years 154 (143 – 165) 101 (92.9 – 107) 156 (143 – 166) 232 (213 – 261) 279

60 years and older 158 (149 – 167) 100 (91.9 – 107) 160 (148 – 172) 242 (226 – 256) 412

Males

Total, 20 years and older 146 (137 – 155) 97.0 (90.8 – 101) 144 (134 – 155) 222 (206 – 254) 471

20–39 years 142 (129 – 156) 95.2 (73.6 – 101) 136 (126 – 147) 222 (187 – 279) 128

40–59 years 152 (139 – 165) 100 (90.4 – 107) 155 (134 – 165) 227 (210 – 284) 139

60 years and older 142 (132 – 153) 93.6 (86.9 – 99.4) 141 (133 – 154) 206 (184 – 250) 204

Females

Total, 20 years and older 159 (152 – 165) 104 (97.0 – 106) 157 (150 – 168) 242 (224 – 261) 520

20–39 years 151 (143 – 160) 99.5 (93.5 – 109) 141 (135 – 160) 232 (210 – 285) 172

40–59 years 156 (144 – 169) 103 (86.2 – 107) 156 (149 – 168) 240 (210 – 264) 140

60 years and older 172 (161 – 184) 107 (88.1 – 124) 177 (161 – 191) 260 (245 – 271) 208
272

2nd 272 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.32.a.1. Plasma arachidonic acid (20:4n-6): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 776 (761 – 791) 445 (418 – 463) 484 (456 – 500) 789 (772 – 805) 1,180 (1,150 – 1,230) 1,320 (1,240 – 1,420) 1,807 Age group 20–39 years 735 (716 – 755) 429 (386 – 455) 479 (445 – 504) 737 (713 – 761) 1,110 (1,050 – 1,230) 1,230 (1,140 – 1,380) 610 40–59 years 793 (772 – 814) 445 (372 – 470) 480 (450 – 496) 808 (785 – 829) 1,220 (1,160 – 1,360) 1,380 (1,260 – 1,560) 514 60 years and older 819 (798 – 841) 448 (421 – 480) 502 (460 – 535) 841 (814 – 868) 1,200 (1,180 – 1,260) 1,430 (1,310 – 1,490) 683 Gender Males 764 (744 – 785) 452 (424 – 473) 480 (455 – 495) 780 (756 – 806) 1,150 (1,090 – 1,220) 1,230 (1,160 – 1,460) 864 Females 787 (769 – 806) 429 (386 – 465) 490 (436 – 520) 792 (769 – 821) 1,220 (1,180 – 1,300) 1,370 (1,320 – 1,460) 943 Race/ethnicity Mexican Americans 722 (678 – 768) 419† (376 – 432) 440 (396 – 487) 726 (675 – 768) 1,110 (1,040 – 1,310) 1,290† (1,140 – 1,460) 376 Non-Hispanic Blacks 884 (839 – 932) 526† (226 – 572) 576 (493 – 611) 883 (831 – 941) 1,330 (1,260 – 1,580) 1,520† (1,360 – 1,770) 310 Non-Hispanic Whites 773 (752 – 795) 445 (419 – 463) 485 (446 – 511) 785 (767 – 807) 1,160 (1,120 – 1,220) 1,260 (1,190 – 1,480) 991 † Estimate is subject to greater uncertainty due to small cell size.
20−39 40−59 60+ 

0 500 1000 1500 

Plasma arachidonic

acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

1500

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 2.32.a. Plasma arachidonic acid (20:4n–6): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma arachidonic Plasma arachidonic acid (μmol/L) acid (μmol/L) 0 500 1000 1500 0 500 1000 

20−39 40−59 60+ 20−39 40−59 60+ 

Females Males 

20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

20−39 40−59 60+ 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 273273
274 2nd 274 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.32.a.2. Plasma arachidonic acid (20:4n-6): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 776 (761 – 791) 538 (516 – 560) 789 (772 – 805) 1,070 (1,040 – 1,110) 1,807

20–39 years 735 (716 – 755) 529 (510 – 542) 737 (713 – 761) 1,000 (959 – 1,080) 610

40–59 years 793 (772 – 814) 534 (488 – 569) 808 (785 – 829) 1,090 (1,050 – 1,140) 514

60 years and older 819 (798 – 841) 562 (533 – 591) 841 (814 – 868) 1,120 (1,090 – 1,140) 683

Males

Total, 20 years and older 764 (744 – 785) 534 (502 – 547) 780 (756 – 806) 1,040 (1,000 – 1,090) 864

20–39 years 739 (710 – 769) 533 (505 – 542) 736 (713 – 766) 999 (945 – 1,100) 282

40–59 years 792 (761 – 825) 529 (487 – 566) 823 (795 – 842) 1,070 (1,020 – 1,150) 247

60 years and older 761 (726 – 798) 532 (453 – 570) 796 (740 – 839) 1,030 (986 – 1,100) 335

Females

Total, 20 years and older 787 (769 – 806) 549 (517 – 575) 792 (769 – 821) 1,100 (1,050 – 1,160) 943

20–39 years 732 (710 – 755) 523 (497 – 552) 738 (705 – 766) 1,010 (956 – 1,120) 328

40–59 years 793 (755 – 833) 534 (464 – 597) 787 (753 – 864) 1,130 (1,020 – 1,230) 267

60 years and older 870 (844 – 896) 620 (551 – 654) 878 (854 – 904) 1,150 (1,120 – 1,200) 348

Table 2.32.a.3. Plasma arachidonic acid (20:4n-6): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 722 (678 – 768) 499 (439 – 536) 726 (675 – 768) 1,030 (975 – 1,080) 376

20–39 years 681 (631 – 735) 483 (413 – 526) 687 (628 – 745) 993 (892 – 1,070) 132

40–59 years 778 (718 – 844) 510† (420 – 602) 774 (749 – 835) 1,120† (948 – 1,350) 93

60 years and older 811 (777 – 846) 567 (496 – 592) 826 (769 – 874) 1,170 (1,050 – 1,330) 151

Males

Total, 20 years and older 719 (669 – 773) 502 (426 – 535) 745 (674 – 788) 1,030 (937 – 1,090) 189

20–39 years 689 (637 – 746) 503† (380 – 540) 707 (609 – 758) 983† (851 – 1,110) 67

40–59 years 770 (675 – 878) 489† (377 – 606) 800 (748 – 843) 1,040† (881 – 1,460) 48

60 years and older 776 (714 – 842) 527† (376 – 590) 811 (643 – 924) 1,090† (1,000 – 1,360) 74

Females

Total, 20 years and older 724 (659 – 796) 479 (352 – 582) 716 (653 – 782) 1,020 (945 – 1,310) 187

20–39 years 670 (591 – 760) 436† (352 – 539) 676 (626 – 723) 987† (856 – 1,310) 65

40–59 years 788 (711 – 874) 567† (447 – 616) 756 (652 – 885) 1,250† (964 – 1,430) 45

60 years and older 844 (790 – 902) 586† (580 – 600) 835 (810 – 873) 1,220† (987 – 1,940) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 275275

Table 2.32.a.4. Plasma arachidonic acid (20:4n-6): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 884 (839 – 932) 630 (588 – 670) 883 (831 – 941) 1,220 (1,160 – 1,330) 310

20–39 years 836 (776 – 901) 602 (542 – 635) 839 (769 – 887) 1,210 (1,040 – 1,380) 126

40–59 years 936 (858 – 1,020) 681† (513 – 711) 942 (827 – 1,040) 1,230† (1,170 – 1,760) 98

60 years and older 919 (859 – 983) 714† (534 – 744) 933 (830 – 1,030) 1,200† (1,160 – 1,330) 86

Males

Total, 20 years and older 870 (817 – 925) 591 (512 – 659) 859 (811 – 976) 1,200 (1,130 – 1,330) 143

20–39 years 811 (737 – 892) 580† (479 – 616) 812 (692 – 891) 1,120† (1,020 – 1,660) 58

40–59 years 953 (875 – 1,040) 666† (501 – 727) 984 (780 – 1,070) 1,230† (1,110 – 2,240) 42

60 years and older 886 (774 – 1,010) 535† (226 – 722) 940 (833 – 1,050) 1,180† (1,130 – 1,440) 43

Females

Total, 20 years and older 895 (829 – 967) 648 (588 – 704) 884 (823 – 958) 1,230 (1,130 – 1,470) 167

20–39 years 858 (773 – 952) 616† (570 – 661) 857 (746 – 955) 1,230† (1,010 – 1,390) 68

40–59 years 923 (818 – 1,040) 679† (468 – 714) 912 (824 – 1,020) 1,230† (1,100 – 2,020) 56

60 years and older 940 (889 – 995) 740† (715 – 762) 916 (809 – 1,040) 1,220† (1,130 – 1,490) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.32.a.5. Plasma arachidonic acid (20:4n-6): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 773 (752 – 795) 539 (497 – 569) 785 (767 – 807) 1,050 (1,010 – 1,100) 991

20–39 years 733 (711 – 755) 533 (490 – 569) 736 (706 – 766) 971 (929 – 1,060) 300

40–59 years 782 (749 – 817) 531 (465 – 579) 800 (777 – 830) 1,040 (1,010 – 1,120) 279

60 years and older 815 (788 – 843) 562 (504 – 604) 839 (811 – 870) 1,110 (1,070 – 1,140) 412

Males

Total, 20 years and older 760 (733 – 788) 534 (488 – 558) 783 (752 – 810) 1,000 (981 – 1,050) 471

20–39 years 731 (702 – 762) 527 (480 – 562) 735 (698 – 771) 957 (899 – 1,160) 128

40–59 years 789 (748 – 832) 539 (476 – 569) 823 (786 – 863) 1,030 (997 – 1,160) 139

60 years and older 752 (711 – 795) 524 (444 – 573) 769 (715 – 833) 998 (962 – 1,110) 204

Females

Total, 20 years and older 785 (761 – 811) 552 (500 – 583) 786 (769 – 816) 1,080 (1,040 – 1,160) 520

20–39 years 733 (701 – 768) 532 (432 – 583) 738 (699 – 768) 997 (920 – 1,150) 172

40–59 years 776 (722 – 835) 530 (403 – 598) 780 (726 – 858) 1,060 (991 – 1,240) 140

60 years and older 873 (841 – 905) 610 (541 – 665) 889 (857 – 916) 1,150 (1,120 – 1,200) 208
276

2nd 276 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.33.a.1. Plasma eicosapentaenoic acid (20:5n-3): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 42.1 (39.5 – 45.0) 14.8 (11.8 – 16.1) 17.1 (15.7 – 18.6) 40.9 (37.6 – 43.8) 113 (103 – 138) 151 (136 – 176) 1,806 Age group 20–39 years 35.9 (33.8 – 38.1) 13.5 (9.10 – 14.9) 15.8 (13.6 – 16.8) 34.2 (32.0 – 36.2) 106 (84.3 – 137) 134 (110 – 193) 609 40–59 years 45.5 (41.8 – 49.5) 17.1 (14.6 – 17.4) 19.0 (17.1 – 20.8) 45.0 (41.0 – 48.3) 114 (102 – 153) 156 (134 – 200) 515 60 years and older 48.5 (43.3 – 54.4) 15.3 (7.79 – 19.9) 20.0 (11.8 – 23.1) 49.4 (43.5 – 53.8) 132 (111 – 162) 175 (139 – 207) 682 Gender Males 43.1 (39.8 – 46.6) 15.7 (11.2 – 16.9) 17.1 (15.5 – 20.1) 41.4 (37.6 – 45.1) 121 (103 – 150) 156 (136 – 199) 863 Females 41.3 (38.7 – 44.1) 14.1 (11.2 – 15.7) 16.9 (15.2 – 18.3) 40.1 (37.5 – 43.1) 111 (99.9 – 143) 146 (118 – 177) 943 Race/ethnicity Mexican Americans 31.0 (28.7 – 33.5) 8.80† (6.03 – 10.9) 10.9 (7.53 – 15.3) 31.4 (28.4 – 35.4) 77.1 (69.0 – 86.4) 86.5† (79.1 – 98.9) 375 Non-Hispanic Blacks 38.8 (34.7 – 43.4) 14.9† (10.8 – 16.1) 16.7 (14.4 – 18.8) 36.1 (33.0 – 41.6) 113 (95.3 – 169) 141† (114 – 247) 310 Non-Hispanic Whites 43.5 (39.8 – 47.7) 15.8 (11.6 – 17.3) 18.1 (14.9 – 20.8) 42.6 (38.1 – 46.0) 112 (101 – 142) 152 (133 – 177) 991 † Estimate is subject to greater uncertainty due to small cell size.
20−39 40−59 60+ 

Plasma eicosapentaenoic

0 20 40 60 80 

acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 2.33.a. Plasma eicosapentaenoic acid (20:5n–3): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma eicosapentaenoic Plasma eicosapentaenoic acid (μmol/L) acid (μmol/L) 0 20 40 60 80 0 20 40 60 80

Non−Hispanic Blacks 

20−39 40−59 60+ 

Females 

20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

20−39 40−59 60+ 

Males 

20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 277277
278 2nd 278 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.33.a.2. Plasma eicosapentaenoic acid (20:5n-3): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 42.1 (39.5 – 45.0) 20.8 (18.9 – 22.2) 40.9 (37.6 – 43.8) 89.9 (80.0 – 99.9) 1,806

20–39 years 35.9 (33.8 – 38.1) 18.2 (16.7 – 20.2) 34.2 (32.0 – 36.2) 74.5 (64.8 – 94.2) 609

40–59 years 45.5 (41.8 – 49.5) 22.8 (19.4 – 26.2) 45.0 (41.0 – 48.3) 92.8 (81.5 – 103) 515

60 years and older 48.5 (43.3 – 54.4) 24.4 (15.6 – 29.1) 49.4 (43.5 – 53.8) 100 (90.6 – 116) 682

Males

Total, 20 years and older 43.1 (39.8 – 46.6) 21.0 (18.5 – 23.0) 41.4 (37.6 – 45.1) 92.8 (81.4 – 104) 863

20–39 years 38.7 (35.6 – 42.0) 18.7 (16.8 – 20.6) 36.1 (34.3 – 40.5) 86.1 (70.8 – 108) 281

40–59 years 47.3 (42.5 – 52.7) 23.4 (20.8 – 26.6) 45.7 (40.0 – 48.9) 97.4 (82.2 – 136) 248

60 years and older 44.2 (38.7 – 50.5) 22.1 (10.4 – 27.5) 44.6 (38.7 – 51.3) 88.7 (74.8 – 109) 334

Females

Total, 20 years and older 41.3 (38.7 – 44.1) 20.4 (18.5 – 22.2) 40.1 (37.5 – 43.1) 86.3 (76.6 – 101) 943

20–39 years 33.3 (30.9 – 36.0) 17.4 (15.8 – 19.8) 31.4 (30.1 – 34.1) 64.6 (56.5 – 80.8) 328

40–59 years 43.9 (40.1 – 48.1) 21.9 (17.2 – 27.5) 43.4 (40.3 – 47.8) 84.6 (76.6 – 100) 267

60 years and older 52.4 (47.2 – 58.1) 25.2 (21.5 – 29.7) 51.7 (49.2 – 57.1) 105 (94.5 – 134) 348

Table 2.33.a.3. Plasma eicosapentaenoic acid (20:5n-3): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 31.0 (28.7 – 33.5) 15.8 (11.1 – 18.4) 31.4 (28.4 – 35.4) 63.8 (58.1 – 70.0) 375

20–39 years 28.0 (24.9 – 31.4) 15.4 (8.96 – 18.3) 28.3 (21.7 – 35.1) 59.1 (50.9 – 68.1) 132

40–59 years 35.5 (30.7 – 41.0) 17.0† (12.2 – 19.0) 35.9 (31.0 – 40.8) 76.2† (56.8 – 91.5) 93

60 years and older 38.2 (35.8 – 40.7) 17.9 (12.9 – 21.6) 40.5 (34.3 – 43.5) 72.9 (61.1 – 95.6) 150

Males

Total, 20 years and older 33.1 (29.9 – 36.8) 16.4 (15.5 – 18.4) 34.3 (29.0 – 37.9) 68.9 (60.4 – 77.9) 188

20–39 years 30.6 (25.4 – 36.8) 16.1† (9.95 – 18.9) 29.4 (22.2 – 40.7) 63.9† (50.2 – 78.0) 67

40–59 years 39.3 (31.6 – 48.8) 16.2† (11.8 – 22.3) 37.6 (30.0 – 51.3) 82.2† (66.1 – 180) 48

60 years and older 33.6 (29.9 – 37.8) 16.0† (12.8 – 18.3) 34.4 (24.2 – 43.5) 56.5† (48.9 – 161) 73

Females

Total, 20 years and older 28.6 (24.9 – 32.8) 13.8 (7.13 – 18.3) 29.1 (23.4 – 35.1) 60.2 (49.1 – 76.5) 187

20–39 years 24.8 (20.1 – 30.7) 10.8† (6.03 – 18.2) 23.5 (19.9 – 31.6) 53.1† (39.3 – 90.1) 65

40–59 years 31.6 (27.4 – 36.4) 17.1† (8.81 – 19.8) 31.3 (26.8 – 37.9) 55.9† (46.3 – 84.0) 45

60 years and older 42.9 (36.7 – 50.1) 22.2† (8.91 – 26.3) 43.3 (38.1 – 49.3) 85.0† (63.7 – 147) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 279279

Table 2.33.a.4. Plasma eicosapentaenoic acid (20:5n-3): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 38.8 (34.7 – 43.4) 19.9 (17.5 – 21.2) 36.1 (33.0 – 41.6) 80.3 (64.8 – 121) 310

20–39 years 33.9 (28.3 – 40.8) 17.9 (15.0 – 20.1) 32.6 (25.1 – 40.6) 64.8 (53.4 – 253) 126

40–59 years 42.9 (37.2 – 49.6) 20.8† (16.4 – 24.8) 39.9 (35.3 – 44.2) 96.3† (72.1 – 147) 98

60 years and older 46.0 (39.2 – 53.9) 27.2† (19.4 – 30.4) 44.5 (36.2 – 51.1) 88.6† (64.3 – 209) 86

Males

Total, 20 years and older 39.9 (34.4 – 46.2) 18.9 (15.3 – 22.2) 35.5 (32.4 – 41.6) 106 (70.6 – 134) 143

20–39 years 34.9 (26.9 – 45.3) 16.6† (12.9 – 19.5) 33.3 (24.6 – 43.0) 64.8† (51.9 – 150) 58

40–59 years 44.4 (37.5 – 52.5) 21.0† (17.3 – 26.5) 36.0 (30.8 – 50.1) 117† (79.5 – 206) 42

60 years and older 48.4 (34.5 – 67.7) 26.1† (7.52 – 32.4) 44.4 (35.0 – 59.2) 102† (61.1 – 209) 43

Females

Total, 20 years and older 38.0 (34.0 – 42.4) 20.1 (18.5 – 21.4) 36.2 (30.4 – 43.9) 71.2 (61.3 – 105) 167

20–39 years 33.2 (27.9 – 39.5) 18.6† (13.2 – 20.4) 29.7 (25.6 – 35.7) 64.3† (44.7 – 253) 68

40–59 years 41.8 (34.9 – 50.2) 19.8† (12.6 – 25.5) 41.3 (35.8 – 46.4) 71.2† (64.0 – 193) 56

60 years and older 44.5 (39.7 – 50.0) 25.5† (20.0 – 30.5) 44.1 (35.2 – 51.1) 75.9† (62.8 – 104) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.33.a.5. Plasma eicosapentaenoic acid (20:5n-3): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 43.5 (39.8 – 47.7) 21.9 (18.6 – 24.7) 42.6 (38.1 – 46.0) 90.5 (78.4 – 102) 991

20–39 years 37.5 (34.3 – 41.0) 20.4 (16.3 – 21.9) 35.3 (32.0 – 38.3) 74.7 (63.8 – 110) 299

40–59 years 45.8 (41.5 – 50.6) 23.9 (18.8 – 27.7) 45.2 (40.5 – 48.7) 89.0 (78.7 – 101) 280

60 years and older 49.0 (42.5 – 56.5) 23.5 (11.7 – 29.6) 49.9 (44.2 – 54.8) 101 (91.7 – 117) 412

Males

Total, 20 years and older 44.3 (40.1 – 48.9) 21.9 (17.3 – 25.8) 43.1 (37.6 – 47.6) 89.8 (78.2 – 105) 471

20–39 years 40.1 (35.9 – 44.7) 20.6 (16.9 – 22.7) 37.8 (34.8 – 42.9) 89.0 (67.8 – 119) 127

40–59 years 48.0 (42.2 – 54.6) 25.1 (20.7 – 27.5) 47.3 (40.0 – 50.2) 92.4 (80.9 – 140) 140

60 years and older 44.3 (38.0 – 51.6) 21.8 (10.3 – 28.6) 44.8 (37.6 – 52.3) 87.2 (75.6 – 105) 204

Females

Total, 20 years and older 42.9 (39.0 – 47.2) 21.8 (18.3 – 24.6) 42.0 (37.9 – 45.6) 91.3 (76.7 – 104) 520

20–39 years 35.4 (31.7 – 39.4) 18.2 (15.8 – 21.9) 31.9 (30.2 – 37.0) 68.2 (54.3 – 112) 172

40–59 years 43.8 (39.1 – 48.9) 22.3 (12.3 – 30.0) 43.3 (37.8 – 48.4) 81.0 (74.2 – 100) 140

60 years and older 53.5 (46.4 – 61.6) 24.6 (18.7 – 30.9) 53.5 (49.3 – 59.7) 110 (96.5 – 138) 208
280

2nd 280 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.34.a.1. Plasma docosatetraenoic acid (22:4n-6): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 25.0 (24.4 – 25.6) 12.1 (10.4 – 13.1) 14.4 (13.3 – 14.9) 24.7 (24.1 – 25.6) 43.0 (41.6 – 44.7) 47.7 (45.4 – 53.5) 1,808 Age group 20–39 years 24.4 (23.4 – 25.4) 12.2 (10.4 – 13.8) 14.3 (13.1 – 15.0) 23.9 (23.1 – 24.9) 41.1 (38.8 – 46.0) 47.1 (42.8 – 58.0) 610 40–59 years 25.5 (24.5 – 26.4) 11.2 (9.62 – 12.9) 14.3 (12.0 – 15.4) 25.0 (24.3 – 26.6) 44.5 (42.1 – 46.2) 50.0 (45.0 – 63.4) 515 60 years and older 25.3 (24.6 – 26.0) 12.6 (9.34 – 14.4) 14.8 (12.9 – 15.8) 25.7 (24.5 – 26.6) 42.2 (39.6 – 45.3) 47.1 (44.7 – 49.5) 683 Gender Males 25.3 (24.4 – 26.2) 11.8 (9.72 – 13.1) 14.5 (13.5 – 14.9) 25.0 (24.3 – 26.1) 42.4 (41.0 – 44.9) 46.8 (44.6 – 58.2) 865 Females 24.7 (24.0 – 25.5) 12.2 (9.93 – 13.9) 14.3 (13.0 – 15.1) 24.5 (23.6 – 25.6) 43.7 (41.4 – 45.9) 48.0 (44.8 – 56.3) 943 Race/ethnicity Mexican Americans 27.5 (25.6 – 29.5) 13.1† (11.2 – 15.6) 15.8 (12.9 – 16.6) 27.4 (25.1 – 29.6) 47.3 (45.9 – 53.3) 58.5† (48.0 – 66.9) 376 Non-Hispanic Blacks 26.0 (25.1 – 26.8) 13.4† (9.11 – 15.0) 15.0 (13.2 – 16.7) 25.8 (24.3 – 26.8) 45.0 (42.0 – 46.7) 50.4† (46.1 – 72.9) 310 Non-Hispanic Whites 24.8 (23.9 – 25.6) 12.1 (10.0 – 13.5) 14.5 (13.0 – 15.1) 24.6 (23.9 – 25.6) 41.9 (39.6 – 44.7) 47.2 (44.5 – 56.1) 992 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

Plasma docosatetraenoic

0 10 20 30 40 

acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 2.34.a. Plasma docosatetraenoic acid (22:4n–6): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma docosatetraenoic Plasma docosatetraenoic acid (μmol/L) acid (μmol/L) 0 10 20 30 40 0 10 20 30 40 

Non−Hispanic Blacks 

20−39 40−59 60+ 

Females 

20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

20−39 40−59 60+ 

Males 

20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 281281
282 2nd 282 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.34.a.2. Plasma docosatetraenoic acid (22:4n-6): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 25.0 (24.4 – 25.6) 16.8 (15.7 – 17.4) 24.7 (24.1 – 25.6) 37.7 (36.7 – 39.4) 1,808

20–39 years 24.4 (23.4 – 25.4) 16.7 (15.0 – 17.5) 23.9 (23.1 – 24.9) 37.1 (34.7 – 39.1) 610

40–59 years 25.5 (24.5 – 26.4) 17.0 (14.8 – 18.0) 25.0 (24.3 – 26.6) 39.4 (37.4 – 41.6) 515

60 years and older 25.3 (24.6 – 26.0) 16.7 (16.0 – 17.5) 25.7 (24.5 – 26.6) 37.0 (36.3 – 38.3) 683

Males

Total, 20 years and older 25.3 (24.4 – 26.2) 16.9 (15.8 – 18.0) 25.0 (24.3 – 26.1) 38.2 (36.5 – 40.0) 865

20–39 years 25.2 (23.8 – 26.6) 17.1 (14.8 – 18.7) 24.5 (23.6 – 26.1) 38.3 (35.5 – 40.8) 282

40–59 years 26.1 (24.9 – 27.3) 17.3 (14.7 – 19.5) 25.9 (24.5 – 27.9) 39.8 (36.8 – 43.7) 248

60 years and older 24.1 (22.9 – 25.3) 16.0 (14.8 – 16.8) 24.3 (22.5 – 26.5) 35.9 (34.2 – 37.6) 335

Females

Total, 20 years and older 24.7 (24.0 – 25.5) 16.5 (15.4 – 17.4) 24.5 (23.6 – 25.6) 37.5 (36.0 – 40.6) 943

20–39 years 23.6 (22.5 – 24.8) 15.8 (14.4 – 17.1) 23.1 (21.3 – 24.7) 35.9 (32.7 – 38.8) 328

40–59 years 24.9 (23.4 – 26.5) 15.6 (14.5 – 17.5) 24.6 (23.4 – 26.4) 38.3 (35.3 – 43.3) 267

60 years and older 26.3 (25.1 – 27.6) 17.6 (16.4 – 18.5) 26.2 (24.9 – 27.8) 38.3 (36.3 – 43.9) 348

Table 2.34.a.3. Plasma docosatetraenoic acid (22:4n-6): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 27.5 (25.6 – 29.5) 17.9 (15.5 – 19.6) 27.4 (25.1 – 29.6) 43.1 (40.6 – 46.6) 376

20–39 years 26.3 (24.0 – 28.8) 16.4 (12.1 – 19.5) 26.1 (21.9 – 29.9) 41.1 (36.6 – 47.8) 132

40–59 years 29.1 (26.8 – 31.6) 18.2† (13.2 – 20.2) 28.4 (26.2 – 31.2) 45.6† (42.2 – 59.9) 93

60 years and older 30.5 (29.3 – 31.8) 20.6 (17.6 – 22.4) 30.2 (28.3 – 32.1) 43.6 (40.4 – 48.5) 151

Males

Total, 20 years and older 27.7 (25.0 – 30.8) 18.4 (13.6 – 20.3) 27.3 (24.4 – 31.1) 41.5 (39.1 – 48.7) 189

20–39 years 26.9 (23.6 – 30.6) 18.5† (12.6 – 20.7) 26.2 (22.5 – 29.9) 40.4† (36.1 – 58.6) 67

40–59 years 29.1 (24.5 – 34.6) 17.9† (13.8 – 21.3) 28.3 (25.3 – 33.8) 44.6† (37.0 – 63.5) 48

60 years and older 29.4 (26.2 – 32.9) 18.8† (17.0 – 21.2) 28.5 (24.6 – 34.1) 45.0† (37.4 – 67.2) 74

Females

Total, 20 years and older 27.2 (24.6 – 30.1) 16.9 (11.4 – 19.7) 27.6 (23.8 – 30.3) 43.5 (40.3 – 50.5) 187

20–39 years 25.5 (22.2 – 29.2) 15.6† (11.2 – 18.0) 25.1 (20.0 – 32.3) 42.9† (34.4 – 58.4) 65

40–59 years 29.0 (25.6 – 32.9) 18.5† (13.2 – 21.6) 27.2 (23.7 – 31.6) 45.8† (42.0 – 61.3) 45

60 years and older 31.6 (30.2 – 33.1) 20.8† (17.8 – 25.8) 31.1 (29.8 – 33.2) 41.7† (36.9 – 66.9) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 283283

Table 2.34.a.4. Plasma docosatetraenoic acid (22:4n-6): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 26.0 (25.1 – 26.8) 17.4 (15.5 – 18.7) 25.8 (24.3 – 26.8) 38.6 (37.0 – 41.1) 310

20–39 years 25.3 (24.1 – 26.4) 17.5 (14.8 – 18.9) 24.0 (22.6 – 26.3) 37.8 (34.6 – 44.2) 126

40–59 years 27.2 (25.0 – 29.5) 17.4† (14.3 – 19.8) 26.7 (24.7 – 28.2) 41.1† (38.8 – 46.3) 98

60 years and older 25.6 (22.9 – 28.6) 16.8† (9.11 – 20.5) 25.8 (24.0 – 29.4) 35.7† (33.3 – 40.3) 86

Males

Total, 20 years and older 26.7 (24.6 – 28.9) 17.5 (13.0 – 19.5) 25.8 (23.0 – 29.1) 41.6 (38.0 – 46.0) 143

20–39 years 25.7 (24.1 – 27.5) 17.5† (11.3 – 19.7) 23.8 (21.7 – 27.5) 39.9† (34.0 – 75.9) 58

40–59 years 28.6 (24.8 – 33.0) 18.0† (12.7 – 20.7) 26.9 (23.7 – 30.4) 41.9† (36.6 – 96.8) 42

60 years and older 25.6 (20.3 – 32.3) 15.3† (9.11 – 23.9) 26.0 (24.1 – 31.6) 37.0† (32.0 – 47.5) 43

Females

Total, 20 years and older 25.4 (24.0 – 27.0) 17.3 (15.1 – 18.7) 25.6 (23.6 – 27.2) 36.4 (34.4 – 40.4) 167

20–39 years 24.9 (23.1 – 26.8) 17.5† (13.4 – 19.2) 24.5 (22.3 – 27.7) 35.9† (30.8 – 46.3) 68

40–59 years 26.1 (22.7 – 30.1) 15.6† (13.4 – 20.0) 26.6 (22.7 – 27.9) 39.1† (31.1 – 118) 56

60 years and older 25.6 (23.6 – 27.6) 17.5† (13.4 – 21.3) 25.1 (23.5 – 27.4) 35.5† (32.5 – 36.6) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.34.a.5. Plasma docosatetraenoic acid (22:4n-6): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 24.8 (23.9 – 25.6) 16.8 (15.6 – 17.5) 24.6 (23.9 – 25.6) 36.8 (35.3 – 37.9) 992

20–39 years 24.1 (22.8 – 25.6) 16.4 (14.6 – 17.6) 23.8 (22.9 – 24.9) 35.5 (32.1 – 39.6) 300

40–59 years 25.0 (23.5 – 26.6) 17.2 (14.5 – 18.6) 24.7 (23.6 – 26.5) 36.8 (34.8 – 41.3) 280

60 years and older 25.2 (24.3 – 26.0) 16.6 (15.6 – 17.4) 25.6 (24.1 – 27.0) 36.9 (36.3 – 38.2) 412

Males

Total, 20 years and older 24.9 (23.8 – 26.1) 16.9 (15.0 – 18.1) 24.7 (24.0 – 26.1) 36.7 (35.1 – 38.3) 472

20–39 years 24.8 (22.9 – 26.7) 17.0 (12.5 – 18.9) 24.3 (23.3 – 26.1) 36.3 (33.0 – 39.7) 128

40–59 years 25.8 (24.1 – 27.5) 17.8 (10.9 – 19.8) 25.2 (24.4 – 27.9) 36.9 (35.2 – 44.0) 140

60 years and older 23.9 (22.5 – 25.4) 15.9 (14.5 – 16.8) 24.1 (22.1 – 26.6) 34.9 (33.5 – 37.2) 204

Females

Total, 20 years and older 24.6 (23.7 – 25.6) 16.6 (15.4 – 17.4) 24.4 (23.5 – 25.6) 36.9 (34.4 – 41.0) 520

20–39 years 23.6 (21.9 – 25.4) 15.8 (14.3 – 17.2) 23.0 (21.0 – 25.1) 34.6 (31.9 – 45.6) 172

40–59 years 24.4 (22.4 – 26.6) 15.9 (13.7 – 18.0) 24.3 (22.5 – 25.9) 35.5 (32.9 – 44.5) 140

60 years and older 26.3 (25.0 – 27.6) 17.3 (16.5 – 18.0) 26.2 (24.7 – 28.1) 38.7 (36.3 – 44.4) 208
284

2nd 284 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.35.a.1. Plasma docosapentaenoic-3 acid (22:5n-3): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 41.6 (40.2 – 43.1) 22.1 (17.2 – 23.8) 24.5 (22.8 – 25.8) 41.4 (40.0 – 42.8) 72.7 (69.7 – 76.7) 82.9 (78.5 – 92.2) 1,808 Age group 20–39 years 38.1 (37.1 – 39.0) 20.0 (15.1 – 22.7) 23.2 (20.9 – 24.4) 38.0 (36.8 – 39.3) 63.0 (58.0 – 73.3) 73.0 (65.5 – 95.1) 610 40–59 years 43.1 (41.1 – 45.3) 22.2 (13.5 – 24.3) 24.9 (20.6 – 26.9) 43.2 (40.6 – 46.0) 77.0 (72.6 – 81.0) 84.9 (79.4 – 105) 515 60 years and older 45.5 (42.3 – 48.8) 24.5 (11.7 – 26.7) 26.5 (23.6 – 28.5) 45.7 (42.8 – 49.1) 74.0 (70.7 – 81.9) 82.0 (76.6 – 97.8) 683 Gender Males 42.8 (41.0 – 44.8) 24.2 (15.0 – 25.6) 26.2 (24.7 – 27.1) 42.5 (40.6 – 44.1) 72.7 (68.1 – 81.6) 87.2 (78.7 – 97.2) 865 Females 40.5 (39.1 – 42.0) 20.5 (13.6 – 22.8) 23.1 (20.7 – 24.5) 40.6 (38.8 – 42.0) 72.7 (67.8 – 78.6) 80.4 (75.5 – 89.8) 943 Race/ethnicity Mexican Americans 39.9 (37.2 – 42.9) 16.9† (12.1 – 22.3) 22.4 (14.1 – 25.0) 40.0 (36.4 – 44.1) 71.5 (67.8 – 79.3) 80.9† (72.5 – 112) 376 Non-Hispanic Blacks 38.9 (36.8 – 41.0) 20.1† (17.5 – 21.5) 22.3 (20.6 – 23.8) 38.1 (36.2 – 40.0) 64.5 (62.0 – 80.1) 85.0† (67.0 – 108) 310 Non-Hispanic Whites 42.1 (40.1 – 44.1) 22.8 (15.6 – 24.2) 24.7 (22.5 – 26.7) 42.2 (40.4 – 43.8) 71.7 (67.9 – 78.5) 81.2 (75.5 – 92.7) 992 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 20 40 60 

Plasma docosapentaenoic−3 acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 2.35.a. Plasma docosapentaenoic−3 acid (22:5n–3): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma docosapentaenoic−3 Plasma docosapentaenoic−3 acid (μmol/L) acid (μmol/L) 0 20 40 60 0 20 40 60 

Non−Hispanic Blacks 

20−39 40−59 60+ 

Females 

20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

20−39 40−59 60+ 

Males 

20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 285285
286 2nd 286 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.35.a.2. Plasma docosapentaenoic-3 acid (22:5n-3): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 41.6 (40.2 – 43.1) 27.4 (26.2 – 28.4) 41.4 (40.0 – 42.8) 62.3 (60.4 – 65.4) 1,808

20–39 years 38.1 (37.1 – 39.0) 26.1 (24.8 – 26.7) 38.0 (36.8 – 39.3) 54.8 (52.4 – 59.9) 610

40–59 years 43.1 (41.1 – 45.3) 27.6 (26.0 – 29.8) 43.2 (40.6 – 46.0) 65.2 (61.6 – 69.7) 515

60 years and older 45.5 (42.3 – 48.8) 29.6 (25.8 – 33.7) 45.7 (42.8 – 49.1) 67.6 (63.0 – 72.4) 683

Males

Total, 20 years and older 42.8 (41.0 – 44.8) 28.8 (26.9 – 30.4) 42.5 (40.6 – 44.1) 63.7 (60.0 – 68.0) 865

20–39 years 40.8 (39.1 – 42.6) 27.3 (25.6 – 29.1) 40.5 (38.5 – 42.9) 59.1 (54.0 – 66.2) 282

40–59 years 44.9 (41.9 – 48.0) 30.2 (28.4 – 31.6) 44.2 (40.7 – 47.8) 68.0 (63.3 – 77.9) 248

60 years and older 43.1 (39.2 – 47.4) 28.7 (23.4 – 33.1) 42.9 (40.9 – 47.2) 60.3 (58.1 – 66.1) 335

Females

Total, 20 years and older 40.5 (39.1 – 42.0) 26.2 (24.8 – 27.4) 40.6 (38.8 – 42.0) 61.4 (59.9 – 65.0) 943

20–39 years 35.6 (34.4 – 36.7) 23.9 (22.8 – 25.7) 35.8 (34.2 – 37.7) 50.4 (48.4 – 56.6) 328

40–59 years 41.6 (39.3 – 44.1) 26.1 (23.1 – 27.7) 41.9 (39.3 – 44.7) 61.2 (58.6 – 71.2) 267

60 years and older 47.5 (44.8 – 50.3) 30.0 (26.8 – 34.2) 48.0 (44.5 – 50.6) 70.1 (67.7 – 74.5) 348

Table 2.35.a.3. Plasma docosapentaenoic-3 acid (22:5n-3): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 39.9 (37.2 – 42.9) 25.9 (20.2 – 29.5) 40.0 (36.4 – 44.1) 61.2 (57.8 – 67.9) 376

20–39 years 36.9 (33.4 – 40.7) 24.4 (15.2 – 27.2) 36.8 (34.2 – 39.9) 54.9 (50.1 – 75.1) 132

40–59 years 44.5 (39.4 – 50.3) 27.8† (25.5 – 30.9) 44.9 (39.4 – 48.2) 69.4† (58.3 – 127) 93

60 years and older 46.5 (45.2 – 47.9) 30.5 (25.7 – 35.6) 46.6 (44.5 – 50.8) 67.4 (57.5 – 80.9) 151

Males

Total, 20 years and older 41.6 (37.6 – 46.0) 26.8 (22.1 – 30.9) 40.5 (36.3 – 46.4) 67.4 (59.1 – 74.5) 189

20–39 years 38.9 (34.0 – 44.4) 25.4† (15.2 – 30.7) 37.2 (35.5 – 40.8) 60.5† (52.3 – 73.1) 67

40–59 years 47.3 (37.9 – 59.0) 29.4† (26.2 – 31.9) 46.6 (33.3 – 60.1) 76.8† (55.8 – 127) 48

60 years and older 44.3 (40.8 – 48.0) 27.9† (20.5 – 32.2) 46.4 (40.6 – 50.0) 63.3† (55.2 – 83.1) 74

Females

Total, 20 years and older 38.0 (34.6 – 41.6) 24.3 (13.1 – 29.6) 39.2 (34.1 – 44.9) 57.5 (52.2 – 60.8) 187

20–39 years 34.3 (29.6 – 39.9) 20.0† (12.1 – 28.3) 35.3 (30.6 – 41.1) 50.6† (47.1 – 85.4) 65

40–59 years 41.6 (38.4 – 45.0) 25.9† (17.2 – 32.5) 41.5 (36.9 – 47.2) 60.2† (55.9 – 74.8) 45

60 years and older 48.7 (45.6 – 52.0) 31.5† (27.6 – 39.2) 50.2 (44.4 – 52.9) 69.2† (57.4 – 90.2) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 287287

Table 2.35.a.4. Plasma docosapentaenoic-3 acid (22:5n-3): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 38.9 (36.8 – 41.0) 25.6 (24.6 – 26.5) 38.1 (36.2 – 40.0) 59.3 (55.1 – 62.4) 310

20–39 years 36.0 (32.7 – 39.5) 24.3 (21.5 – 25.8) 35.2 (32.0 – 38.1) 54.6 (48.6 – 63.5) 126

40–59 years 41.1 (37.4 – 45.2) 26.6† (24.3 – 28.0) 40.0 (35.2 – 44.2) 60.3† (57.2 – 84.5) 98

60 years and older 43.0 (40.4 – 45.8) 30.5† (21.3 – 34.2) 43.0 (39.5 – 47.7) 60.6† (54.6 – 63.6) 86

Males

Total, 20 years and older 40.8 (38.5 – 43.2) 26.1 (24.7 – 29.2) 38.7 (37.7 – 41.4) 60.2 (58.8 – 69.2) 143

20–39 years 38.1 (33.8 – 43.0) 25.3† (20.3 – 28.5) 37.7 (32.3 – 39.9) 59.8† (44.2 – 131) 58

40–59 years 43.4 (41.7 – 45.1) 28.4† (24.7 – 30.5) 40.3 (38.6 – 42.1) 68.5† (57.2 – 108) 42

60 years and older 44.4 (41.1 – 48.0) 31.7† (17.8 – 36.7) 44.9 (40.9 – 50.5) 60.5† (58.2 – 64.6) 43

Females

Total, 20 years and older 37.4 (35.0 – 40.1) 24.4 (22.4 – 26.2) 36.8 (34.3 – 40.1) 54.4 (51.8 – 62.5) 167

20–39 years 34.3 (31.2 – 37.7) 21.9† (18.8 – 25.8) 33.5 (28.9 – 38.8) 53.0† (45.4 – 64.5) 68

40–59 years 39.5 (33.5 – 46.5) 23.9† (20.6 – 27.1) 39.3 (33.9 – 44.8) 58.0† (48.6 – 148) 56

60 years and older 42.2 (39.0 – 45.7) 29.5† (25.6 – 34.3) 41.7 (37.8 – 47.7) 56.6† (52.5 – 70.1) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.35.a.5. Plasma docosapentaenoic-3 acid (22:5n-3): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 42.1 (40.1 – 44.1) 27.7 (26.1 – 29.0) 42.2 (40.4 – 43.8) 62.8 (60.0 – 67.4) 992

20–39 years 38.8 (37.5 – 40.2) 26.7 (24.8 – 28.1) 38.8 (36.8 – 41.0) 54.7 (52.1 – 61.5) 300

40–59 years 42.8 (40.1 – 45.7) 27.6 (24.8 – 30.1) 43.3 (39.7 – 47.0) 63.6 (60.8 – 68.0) 280

60 years and older 45.6 (41.8 – 49.8) 29.5 (25.0 – 33.7) 45.8 (42.5 – 50.1) 68.0 (64.1 – 73.0) 412

Males

Total, 20 years and older 43.1 (40.7 – 45.6) 29.2 (26.9 – 31.2) 43.1 (40.6 – 45.3) 63.0 (59.6 – 66.9) 472

20–39 years 41.5 (39.4 – 43.6) 27.5 (26.4 – 29.3) 42.3 (39.1 – 44.4) 56.4 (53.0 – 72.1) 128

40–59 years 44.5 (41.1 – 48.2) 30.8 (27.1 – 32.2) 44.2 (39.7 – 48.3) 66.1 (61.6 – 75.0) 140

60 years and older 43.0 (38.4 – 48.1) 29.5 (14.9 – 33.9) 42.7 (39.7 – 47.5) 60.2 (57.3 – 70.0) 204

Females

Total, 20 years and older 41.2 (39.3 – 43.1) 26.5 (24.5 – 28.2) 41.3 (38.8 – 43.0) 62.4 (59.2 – 71.1) 520

20–39 years 36.6 (34.7 – 38.6) 24.8 (22.8 – 28.3) 36.8 (34.2 – 38.5) 50.0 (46.5 – 61.2) 172

40–59 years 41.1 (38.0 – 44.6) 26.0 (22.3 – 27.7) 42.0 (38.8 – 46.6) 60.1 (57.1 – 73.0) 140

60 years and older 48.0 (44.4 – 51.8) 29.5 (24.8 – 34.5) 48.4 (44.1 – 52.6) 72.4 (68.4 – 75.1) 208
288

2nd 288 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.36.a.1. Plasma docosapentaenoic-6 acid (22:5n-6): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 19.6 (18.9 – 20.4) 8.56 (7.60 – 9.46) 9.80 (9.30 – 10.5) 19.3 (18.6 – 20.1) 39.0 (36.1 – 42.4) 46.5 (42.9 – 52.2) 1,808 Age group 20–39 years 19.5 (18.6 – 20.5) 9.15 (8.17 – 9.51) 9.88 (9.25 – 11.1) 18.8 (17.9 – 20.0) 41.4 (35.5 – 46.3) 47.8 (45.1 – 54.4) 610 40–59 years 19.4 (18.4 – 20.4) 8.37 (4.40 – 9.67) 9.80 (7.79 – 11.1) 19.0 (18.3 – 20.5) 36.0 (34.5 – 39.1) 41.6 (37.2 – 50.8) 515 60 years and older 20.3 (19.5 – 21.2) 8.00 (5.88 – 8.84) 9.63 (8.26 – 10.8) 20.5 (19.5 – 21.5) 41.4 (37.9 – 48.4) 52.1 (46.8 – 58.0) 683 Gender Males 18.6 (17.7 – 19.7) 8.11 (6.96 – 9.23) 9.66 (8.83 – 10.4) 18.6 (17.8 – 19.3) 34.6 (32.2 – 40.5) 42.8 (38.6 – 45.2) 865 Females 20.6 (19.8 – 21.4) 8.92 (7.74 – 9.55) 9.95 (9.30 – 11.2) 20.5 (19.2 – 21.7) 41.9 (38.5 – 47.8) 50.6 (46.4 – 59.0) 943 Race/ethnicity Mexican Americans 23.5 (21.0 – 26.2) 10.4† (6.86 – 11.5) 11.6 (8.94 – 13.5) 22.8 (19.7 – 27.1) 47.6 (44.2 – 56.0) 53.6† (48.5 – 60.2) 376 Non-Hispanic Blacks 21.3 (20.3 – 22.4) 9.27† (5.89 – 10.3) 10.2 (9.35 – 11.6) 20.8 (19.7 – 22.4) 43.0 (40.4 – 50.4) 50.6† (45.0 – 63.2) 310 Non-Hispanic Whites 19.1 (18.3 – 19.9) 8.15 (7.49 – 9.20) 9.67 (8.52 – 10.6) 18.9 (18.3 – 19.8) 36.0 (34.0 – 40.9) 45.2 (40.7 – 51.4) 992 † Estimate is subject to greater uncertainty due to small cell size. 
20−39 40−59 60+ 

0 10 20 30 40 

Plasma docosapentaenoic−6 acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 2.36.a. Plasma docosapentaenoic−6 acid (22:5n–6): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Plasma docosapentaenoic−6 Plasma docosapentaenoic−6 acid (μmol/L) acid (μmol/L) 0 10 20 30 40 0 10 20 30 40

Non−Hispanic Blacks 

20−39 40−59 60+ 

Females 

20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

20−39 40−59 60+ 

Males 

20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

2. Fat-Soluble 1. Water Vitamins & Nutr -Soluble Vitamins ient 289289
290 2nd 290 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.36.a.2. Plasma docosapentaenoic-6 acid (22:5n-6): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 19.6 (18.9 – 20.4) 11.8 (11.4 – 12.3) 19.3 (18.6 – 20.1) 32.5 (31.4 – 33.9) 1,808

20–39 years 19.5 (18.6 – 20.5) 11.8 (11.2 – 12.9) 18.8 (17.9 – 20.0) 32.4 (31.3 – 34.8) 610

40–59 years 19.4 (18.4 – 20.4) 11.5 (11.2 – 12.1) 19.0 (18.3 – 20.5) 31.8 (29.8 – 34.2) 515

60 years and older 20.3 (19.5 – 21.2) 12.2 (10.6 – 12.8) 20.5 (19.5 – 21.5) 33.2 (31.2 – 38.6) 683

Males

Total, 20 years and older 18.6 (17.7 – 19.7) 11.7 (11.0 – 12.3) 18.6 (17.8 – 19.3) 29.8 (28.8 – 32.1) 865

20–39 years 18.4 (17.3 – 19.6) 12.1 (10.8 – 13.1) 18.0 (17.1 – 18.7) 29.6 (27.2 – 33.4) 282

40–59 years 19.0 (17.7 – 20.3) 11.8 (10.6 – 12.4) 19.0 (17.6 – 20.7) 29.4 (28.1 – 33.3) 248

60 years and older 18.4 (17.2 – 19.7) 10.4 (9.64 – 11.7) 18.7 (17.7 – 20.0) 31.2 (27.9 – 35.6) 335

Females

Total, 20 years and older 20.6 (19.8 – 21.4) 12.0 (11.3 – 12.7) 20.5 (19.2 – 21.7) 34.5 (33.0 – 36.6) 943

20–39 years 20.6 (19.4 – 21.9) 11.6 (9.88 – 13.0) 20.5 (18.7 – 22.2) 35.0 (32.4 – 41.2) 328

40–59 years 19.8 (18.3 – 21.3) 11.3 (10.7 – 12.1) 19.1 (17.8 – 21.7) 34.3 (31.1 – 36.4) 267

60 years and older 22.0 (20.7 – 23.3) 13.7 (12.4 – 14.4) 22.0 (20.7 – 23.1) 35.5 (31.4 – 48.5) 348

Table 2.36.a.3. Plasma docosapentaenoic-6 acid (22:5n-6): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 23.5 (21.0 – 26.2) 14.1 (11.5 – 15.0) 22.8 (19.7 – 27.1) 42.8 (38.9 – 46.1) 376

20–39 years 22.0 (19.6 – 24.8) 13.2 (9.09 – 14.9) 21.0 (18.0 – 25.7) 40.8 (33.5 – 45.8) 132

40–59 years 24.9 (21.6 – 28.7) 14.2† (8.50 – 16.5) 24.7 (20.6 – 29.6) 43.8† (38.4 – 52.6) 93

60 years and older 28.5 (24.4 – 33.3) 17.8 (15.1 – 19.7) 28.2 (23.4 – 33.9) 45.1 (36.8 – 71.9) 151

Males

Total, 20 years and older 22.4 (19.8 – 25.4) 13.7 (10.4 – 15.7) 21.2 (19.1 – 26.0) 38.7 (34.0 – 44.6) 189

20–39 years 21.1 (18.5 – 24.1) 13.3† (9.51 – 15.4) 19.8 (17.6 – 23.2) 33.4† (29.0 – 51.2) 67

40–59 years 24.1 (19.7 – 29.6) 13.8† (6.48 – 17.7) 24.5 (18.1 – 33.3) 42.5† (31.7 – 52.7) 48

60 years and older 26.7 (22.9 – 31.2) 16.4† (12.7 – 19.2) 26.1 (20.7 – 33.2) 41.8† (35.3 – 56.1) 74

Females

Total, 20 years and older 24.8 (21.5 – 28.7) 14.1 (9.21 – 15.0) 24.5 (20.1 – 31.4) 44.7 (41.4 – 53.8) 187

20–39 years 23.4 (19.3 – 28.2) 12.0† (8.52 – 14.8) 22.1 (15.0 – 32.1) 45.5† (35.2 – 104) 65

40–59 years 25.8 (20.4 – 32.6) 14.4† (10.5 – 16.8) 24.6 (18.0 – 35.8) 43.5† (37.4 – 70.9) 45

60 years and older 30.3 (23.9 – 38.3) 19.5† (14.3 – 21.0) 28.8 (22.4 – 41.5) 48.8† (37.9 – 71.9) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 291291

Table 2.36.a.4. Plasma docosapentaenoic-6 acid (22:5n-6): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 21.3 (20.3 – 22.4) 12.4 (10.4 – 13.5) 20.8 (19.7 – 22.4) 35.3 (33.3 – 41.5) 310

20–39 years 21.0 (19.2 – 22.8) 12.8 (11.7 – 13.4) 19.9 (18.3 – 23.5) 34.8 (31.5 – 50.8) 126

40–59 years 21.5 (19.4 – 23.7) 12.1† (9.42 – 13.5) 21.7 (19.7 – 22.6) 34.9† (30.5 – 44.0) 98

60 years and older 22.1 (18.4 – 26.6) 12.8† (5.89 – 14.9) 22.9 (17.6 – 28.4) 37.7† (32.6 – 45.7) 86

Males

Total, 20 years and older 20.0 (18.1 – 22.2) 11.7 (9.26 – 13.2) 19.8 (18.3 – 21.6) 34.8 (30.9 – 43.6) 143

20–39 years 18.8 (17.2 – 20.6) 11.4† (5.94 – 13.4) 18.9 (15.9 – 19.9) 32.8† (27.6 – 47.8) 58

40–59 years 21.4 (18.2 – 25.1) 12.2† (9.72 – 13.8) 21.7 (18.1 – 23.2) 32.9† (27.0 – 89.5) 42

60 years and older 21.1 (15.6 – 28.7) 9.26† (5.89 – 15.5) 21.5 (16.0 – 31.7) 39.9† (32.2 – 50.3) 43

Females

Total, 20 years and older 22.4 (20.3 – 24.7) 13.0 (10.3 – 14.6) 22.0 (19.5 – 25.3) 35.3 (33.0 – 45.2) 167

20–39 years 22.9 (19.3 – 27.2) 14.0† (9.93 – 16.1) 22.2 (18.4 – 27.0) 35.3† (31.8 – 100) 68

40–59 years 21.6 (18.7 – 24.9) 11.1† (8.75 – 13.5) 21.3 (18.9 – 26.4) 35.1† (28.2 – 99.4) 56

60 years and older 22.8 (19.3 – 26.9) 13.0† (7.21 – 15.0) 23.2 (17.4 – 29.7) 33.7† (32.4 – 47.7) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.36.a.5. Plasma docosapentaenoic-6 acid (22:5n-6): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 19.1 (18.3 – 19.9) 11.7 (11.0 – 12.3) 18.9 (18.3 – 19.8) 31.1 (29.4 – 32.6) 992

20–39 years 19.0 (17.9 – 20.2) 11.6 (9.68 – 12.9) 18.5 (17.3 – 20.3) 31.3 (29.1 – 33.0) 300

40–59 years 18.7 (17.3 – 20.3) 11.4 (10.1 – 12.6) 18.6 (17.6 – 19.6) 29.6 (27.6 – 33.3) 280

60 years and older 19.9 (19.2 – 20.6) 11.9 (10.4 – 12.8) 20.1 (19.3 – 21.3) 31.9 (30.5 – 35.2) 412

Males

Total, 20 years and older 18.0 (17.0 – 19.1) 11.4 (10.1 – 12.3) 18.3 (17.6 – 19.0) 28.3 (26.7 – 30.8) 472

20–39 years 17.7 (16.3 – 19.2) 11.5 (8.97 – 13.1) 17.5 (16.8 – 18.5) 27.4 (22.5 – 39.7) 128

40–59 years 18.3 (16.9 – 19.8) 11.6 (8.23 – 13.7) 18.8 (16.9 – 20.2) 28.7 (25.9 – 31.6) 140

60 years and older 18.1 (16.8 – 19.5) 10.4 (9.64 – 11.7) 18.6 (16.9 – 20.4) 29.9 (26.7 – 33.1) 204

Females

Total, 20 years and older 20.2 (19.3 – 21.1) 12.1 (11.2 – 12.8) 20.2 (18.6 – 21.6) 32.9 (31.3 – 35.6) 520

20–39 years 20.3 (18.9 – 21.9) 11.5 (9.55 – 13.2) 20.5 (18.0 – 22.5) 32.6 (30.9 – 42.8) 172

40–59 years 19.2 (17.1 – 21.4) 11.4 (10.0 – 12.5) 18.4 (16.8 – 21.9) 32.3 (27.4 – 37.2) 140

60 years and older 21.5 (20.4 – 22.7) 13.5 (12.0 – 14.1) 21.6 (20.5 – 22.9) 33.6 (30.5 – 49.5) 208
292

2nd 292 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 2.37.a.1. Plasma docosahexaenoic acid (22:6n-3): Concentrations Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 20 years and older 125 (118 – 133) 54.9 (52.4 – 57.8) 61.1 (56.2 – 65.2) 121 (114 – 128) 277 (248 – 310) 323 (302 – 372) 1,808 Age group 20–39 years 115 (108 – 122) 54.3 (45.5 – 57.3) 58.1 (53.6 – 62.5) 111 (102 – 119) 254 (228 – 316) 316 (275 – 484) 610 40–59 years 125 (115 – 136) 54.1 (50.2 – 58.3) 60.6 (53.8 – 65.6) 121 (111 – 136) 272 (237 – 303) 305 (290 – 400) 515 60 years and older 145 (135 – 156) 64.5 (54.8 – 70.4) 73.5 (56.2 – 81.9) 142 (132 – 154) 305 (268 – 358) 373 (330 – 398) 683 Gender Males 117 (110 – 125) 53.9 (49.3 – 55.7) 57.9 (54.0 – 62.4) 114 (107 – 123) 253 (229 – 299) 303 (277 – 368) 865 Females 133 (125 – 141) 57.8 (48.3 – 63.0) 65.2 (56.1 – 72.0) 127 (121 – 135) 293 (258 – 323) 337 (315 – 385) 943 Race/ethnicity Mexican Americans 111 (105 – 119) 54.4† (46.4 – 58.0) 58.8 (55.2 – 60.2) 111 (99.8 – 123) 211 (191 – 251) 250† (218 – 342) 376 Non-Hispanic Blacks 140 (124 – 157) 64.9† (47.5 – 72.4) 72.5 (59.4 – 80.3) 133 (118 – 152) 304 (254 – 425) 348† (321 – 416) 310 Non-Hispanic Whites 122 (113 – 130) 54.7 (51.3 – 56.2) 59.5 (55.0 – 64.6) 117 (110 – 127) 259 (241 – 294) 315 (283 – 375) 992 † Estimate is subject to greater uncertainty due to small cell size.
1. Water-Soluble Vitamins 293

20−39 40−59 60+ 

Plasma docosahexaenoic

0 50 100 150 200 250

acid (μmol/L) 

Overall 

20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 2.37.a. Plasma docosahexaenoic acid (22:6n–3): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and 

Nutrition Examination Survey, 2003–2004 

Plasma docosahexaenoic Plasma docosahexaenoic

acid (μmol/L) acid (μmol/L) 

0 50 100 150 200 250 0 50 100 150 200 250

Non−Hispanic Blacks 

20−39 40−59 60+ 

Females 

20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

20−39 40−59 60+ 

Males 

20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

2. Fat-Soluble Vitamins & Nutrients 293
294 2nd 294 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 2.37.a.2. Plasma docosahexaenoic acid (22:6n-3): Total population

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for the fasted U.S. population 

aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 125 (118 – 133) 71.7 (67.1 – 74.9) 121 (114 – 128) 227 (208 – 244) 1,808

20–39 years 115 (108 – 122) 67.0 (62.3 – 71.6) 111 (102 – 119) 204 (187 – 234) 610

40–59 years 125 (115 – 136) 70.1 (62.3 – 77.7) 121 (111 – 136) 217 (201 – 244) 515

60 years and older 145 (135 – 156) 84.2 (73.5 – 94.3) 142 (132 – 154) 247 (234 – 268) 683

Males

Total, 20 years and older 117 (110 – 125) 67.9 (62.5 – 71.7) 114 (107 – 123) 206 (189 – 235) 865

20–39 years 107 (99.5 – 115) 62.3 (57.6 – 68.1) 102 (93.2 – 113) 186 (170 – 209) 282

40–59 years 122 (110 – 135) 68.7 (61.4 – 74.4) 118 (106 – 135) 219 (189 – 296) 248

60 years and older 131 (119 – 143) 77.8 (53.6 – 92.8) 125 (117 – 142) 219 (194 – 256) 335

Females

Total, 20 years and older 133 (125 – 141) 75.6 (68.7 – 80.0) 127 (121 – 135) 238 (223 – 256) 943

20–39 years 123 (115 – 133) 72.4 (61.8 – 78.6) 117 (110 – 127) 220 (194 – 283) 328

40–59 years 128 (117 – 138) 72.3 (59.3 – 79.4) 124 (112 – 143) 210 (201 – 256) 267

60 years and older 158 (148 – 169) 91.4 (82.5 – 99.1) 154 (144 – 168) 272 (249 – 307) 348

Table 2.37.a.3. Plasma docosahexaenoic acid (22:6n-3): Mexican Americans

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted Mexican Americans in 

the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 111 (105 – 119) 67.1 (57.8 – 73.0) 111 (99.8 – 123) 185 (165 – 199) 376

20–39 years 102 (91.1 – 114) 60.0 (55.3 – 67.6) 100 (80.6 – 122) 161 (150 – 204) 132

40–59 years 127 (117 – 137) 84.9† (56.6 – 94.3) 125 (112 – 139) 189† (163 – 266) 93

60 years and older 129 (118 – 142) 81.2 (61.1 – 92.2) 131 (114 – 144) 202 (185 – 246) 151

Males

Total, 20 years and older 107 (99.7 – 114) 64.8 (55.1 – 69.2) 104 (95.3 – 124) 165 (158 – 188) 189

20–39 years 96.1 (85.8 – 108) 59.4† (52.4 – 67.1) 99.4 (78.2 – 119) 147† (136 – 158) 67

40–59 years 129 (110 – 152) 83.3† (66.8 – 93.9) 127 (101 – 153) 194† (155 – 355) 48

60 years and older 120 (109 – 132) 69.0† (46.1 – 90.1) 121 (105 – 143) 190† (159 – 272) 74

Females

Total, 20 years and older 118 (105 – 131) 68.8 (52.3 – 83.3) 116 (102 – 133) 191 (166 – 250) 187

20–39 years 110 (90.5 – 134) 60.4† (54.0 – 73.7) 109 (75.7 – 150) 191† (158 – 325) 65

40–59 years 124 (111 – 139) 87.9† (52.3 – 99.1) 119 (110 – 139) 173† (150 – 268) 45

60 years and older 139 (115 – 168) 88.9† (77.0 – 107) 133 (109 – 164) 229† (183 – 334) 77

† Estimate is subject to greater uncertainty due to small cell size. 
2. Fat-Soluble Vitamins & Nutrients 1. Water-Soluble Vitamins 295295

Table 2.37.a.4. Plasma docosahexaenoic acid (22:6n-3): Non-Hispanic blacks

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic blacks 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 140 (124 – 157) 83.4 (72.4 – 90.8) 133 (118 – 152) 251 (207 – 333) 310

20–39 years 128 (107 – 153) 77.2 (66.4 – 89.0) 119 (103 – 140) 237 (177 – 367) 126

40–59 years 142 (127 – 159) 84.1† (69.9 – 95.8) 133 (119 – 157) 234† (204 – 374) 98

60 years and older 173 (155 – 193) 117† (56.2 – 135) 173 (149 – 197) 258† (216 – 368) 86

Males

Total, 20 years and older 129 (114 – 147) 72.4 (60.4 – 82.2) 124 (110 – 145) 233 (198 – 361) 143

20–39 years 112 (89.9 – 141) 67.9† (52.5 – 76.1) 107 (84.5 – 140) 193† (143 – 367) 58

40–59 years 143 (124 – 165) 77.8† (62.1 – 89.4) 131 (113 – 171) 283† (217 – 404) 42

60 years and older 161 (138 – 189) 113† (47.5 – 127) 159 (144 – 175) 251† (195 – 368) 43

Females

Total, 20 years and older 148 (129 – 171) 96.2 (80.8 – 104) 136 (120 – 176) 254 (203 – 442) 167

20–39 years 142 (118 – 172) 93.1† (80.7 – 98.8) 127 (106 – 186) 254† (191 – 340) 68

40–59 years 141 (121 – 165) 90.3† (47.6 – 110) 132 (119 – 163) 208† (184 – 442) 56

60 years and older 181 (162 – 201) 121† (63.8 – 136) 182 (149 – 213) 258† (222 – 351) 43

† Estimate is subject to greater uncertainty due to small cell size. 

Table 2.37.a.5. Plasma docosahexaenoic acid (22:6n-3): Non-Hispanic whites

Geometric mean and selected percentiles of plasma concentrations (in μmol/L) for fasted non-Hispanic whites 

in the U.S. population aged 20 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 20 years and older 122 (113 – 130) 69.8 (64.4 – 74.5) 117 (110 – 127) 215 (202 – 235) 992

20–39 years 111 (102 – 121) 65.2 (58.4 – 72.4) 110 (97.8 – 118) 201 (170 – 258) 300

40–59 years 118 (108 – 130) 65.9 (55.3 – 75.7) 114 (106 – 128) 206 (181 – 252) 280

60 years and older 142 (131 – 155) 84.2 (67.8 – 95.3) 136 (125 – 154) 244 (233 – 266) 412

Males

Total, 20 years and older 113 (105 – 122) 65.3 (59.6 – 71.8) 112 (102 – 121) 198 (178 – 229) 472

20–39 years 102 (94.4 – 110) 60.8 (54.8 – 68.1) 96.1 (84.4 – 113) 180 (157 – 212) 128

40–59 years 115 (103 – 128) 64.9 (53.7 – 73.5) 113 (97.8 – 127) 194 (167 – 303) 140

60 years and older 128 (116 – 142) 77.0 (49.3 – 93.0) 121 (113 – 141) 213 (188 – 254) 204

Females

Total, 20 years and older 130 (120 – 140) 74.4 (65.3 – 79.0) 124 (116 – 133) 229 (209 – 259) 520

20–39 years 121 (109 – 134) 72.4 (54.3 – 79.2) 114 (104 – 127) 204 (178 – 315) 172

40–59 years 122 (111 – 133) 68.0 (52.5 – 78.9) 120 (106 – 139) 207 (188 – 244) 140

60 years and older 156 (142 – 170) 89.5 (81.0 – 97.4) 150 (132 – 174) 274 (243 – 330) 208
296 2nd 296 2 National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

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saturated fat in the prevention of cardiovascular disease: where does the evidence stand in 2010? Am J Clin Nutr.

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treatment of high blood cholesterol in adults (Adult Treatment Panel III). JAMA. 2001;285(19):2486–2497

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biomarker of dietary intake. Progress in Lipid Research. 2008;47:348–80.

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carbohydrates compared with intake of saturated fatty acids and risk of myocardial infarction: importance of the

glycemic index. Am J Clin Nutr. 2010; 91:1764–1768.

Kris-Etherton PM, Harris WS, Appel LJ, for the Nutrition Committee. Fish consumption, fish oil, omega-3 fatty

acids, and cardiovascular disease. Circulation. 2002;106:2747–2757.

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plasma C8-C26 total fatty acids for the biochemical diagnosis of nutritional and metabolic disorders. Mol Genet

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Micha R, Mozaffarian D. Saturated fat and cardiometabolic risk factors, coronary heart disease, stroke, and

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3. Trace Elements 299

3. Trace Elements

Iron-Status Indicators

•	 Ferritin

•	 Soluble transferrin receptor

•	 Body iron

Iodine
300 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Iron-Status Indicators

Background Information

Sources and Physiological Functions. Iron functions as a component of proteins and enzymes.

Almost two-thirds of the iron in the body (approximately 2.5 grams of iron) is found in hemoglobin,

the protein in red blood cells that carries oxygen to tissues, and about 15% is in the myoglobin

of muscle tissue. The average American diet provides 10–15 milligrams (mg) of iron daily in the

form of heme and nonheme iron. Heme iron is found in animal foods that originally contained

hemoglobin and myoglobin, such as red meat, fish, and poultry. Nonheme iron is found in plant

foods, such as lentils and beans, and also is provided in iron-enriched and iron-fortified foods.

Although heme iron is absorbed better than nonheme iron, most dietary iron is nonheme iron

(Miret 2003). Each day the body absorbs approximately 1–2 mg of iron to compensate for the 1

to 2 mg of iron that the (nonmenstruating) body loses (Institute of Medicine 2001). The current

Dietary Guidelines for Americans list iron as a nutrient of concern for specific population groups.

The guidelines recommend that pregnant women take an iron supplement, as recommended by an

obstetrician or other health care provider (U.S. Department of Agriculture 2010).

Health Effects. Transporting iron from one organ to another is accomplished by the reversible

binding of iron to the transport protein, transferrin, which will then form a complex with a highly

specific transferrin receptor (TfR) located on the plasma membrane surfaces of cells. Intracellular

iron availability is regulated through the increased expression of cellular TfR concentration by irondeficient cells. Ferritin is the major iron-storage compound: its production increases in cells as iron

supplies increase. The major function of ferritin is to provide a store of iron which may be used for

haem synthesis when required. Although all cells are capable of storing iron, the liver, spleen, and

bone marrow cells are primary iron-storage sites in people (Institute of Medicine 2001).

Iron deficiency and iron overload are the two major disorders of iron metabolism. Iron-deficiency

anemia is the most severe form of iron deficiency. It is linked to many adverse consequences of iron

deficiency, such as reduced physical capacity (Haas 2001) and poor pregnancy outcomes (Schorr

1994). Iron deficiency with and without anemia, however, has been linked to negative effects

on cognitive development among infants and adolescents (Beard 1999; Grantham-McGregor

2001). Iron overload is the accumulation of excess iron in body tissues, and it usually occurs as

a result of a genetic predisposition to absorb iron in excess of normal. However, it can also be

caused by excessive ingestion of iron supplements or multiple blood transfusions (Pietrangelo

2004). In advanced stages of iron overload disease (hemochromatosis), the iron accumulates in the

parenchymal cells of several organs, but particularly the liver, followed by the heart and pancreas;

this condition can lead to organ dysfunction and even death (Pietrangelo 2004).

Intake Recommendations. The Recommended Dietary Allowance (RDA) for all age groups of

men and postmenopausal women is 8 mg per day; the RDA for premenopausal women is 18 mg

per day. The Tolerable Upper Uptake Level for adults is 45 mg per day of iron, a level based on

gastrointestinal distress as an adverse effect (Institute of Medicine 2001).

Biochemical Indicators and Methods. Ferritin is present in the blood in very low concentrations.

Serum ferritin is in equilibrium with tissue stores, and its concentration declines early in the

development of iron deficiency. Low serum ferritin concentration thus is a sensitive indicator of

iron deficiency, but it does not necessarily reflect the severity of the depletion as it progresses (World

Health Organization 2011). Ferritin is also an acute-phase protein; acute and chronic diseases can

result in increased ferritin concentration, potentially masking an iron-deficiency diagnosis. A review
3. Trace Elements 301

article on serum ferritin written as part of a 2004 WHO/

CDC Technical Consultation on the Assessment of Iron

Status at the Population Level provides comprehensive

information on this topic (Worwood 2007). The

generally accepted cutoff value for serum ferritin below

which iron stores are considered to be depleted is 15

nanogram per milliliter (ng/mL) for people aged 5 years

and older and 12 ng/mL for people younger than 5 years

of age (World Health Organization 2001; World Health

Organization 2011). Serum ferritin concentrations

above 200 ng/mL for adult males and 150 ng/mL for

adult females are considered to represent severe risk of

iron overload (World Health Organization 2001; World

Health Organization 2011).

Soluble TfR (sTfR) is the truncated form of the

membrane-bound TfR that is cleaved and released

into the serum. The amount of sTfR is proportional to

the number of membrane-bound TfR. sTfR circulates

bound to transferrin, and its concentration is not strongly affected by concurrent inflammation

or infection (Beard 2007). Serum sTfR concentration increases when the iron functional pool is

depleted and during activated erythropoiesis (Kuiper-Kramer 1998). It continues to do so as the

severity of iron-deficient erythropoiesis increases, reflecting the increasing number of receptors on

the erythroid cells of the bone marrow. The measurement of sTfR is therefore a powerful tool for the

diagnosis of iron deficiency or for monitoring erythropoiesis.

Serum ferritin is the most sensitive index of iron status when there are residual iron stores,

whereas serum sTfR is more sensitive when there is functional iron deficiency (Skikne 1990).

There is a close, linear relationship between the logarithm of the sTfR to serum ferritin ratio and

stored iron (body iron) expressed as mg per kg body weight (Skikne 1990). Recently Cook et al.

demonstrated that in healthy persons body iron may be estimated from the ratio of sTfR to serum

ferritin (reported in microgram [μg]/mL for both assays) (2003). Body iron is in a positive balance

(≥ 0 mg/kg) when there is residual storage iron or in a negative balance (< 0 mg/kg) when there

is functional iron deficiency. The latter represents a deficit in iron required to maintain a normal

hemoglobin concentration. The body iron methodology allows the full range of iron status of

populations to be evaluated. Other iron status indicators, such as serum iron, total iron binding

capacity, transferrin saturation, and erythrocyte protoporphyrin, were described in the previous

report of this series. They are not included in the current report.

Clinical laboratories typically use conventional units for iron-status indicators: ferritin is

calculated in nanograms per milliliter (ng/mL) and sTfR in milligrams per liter (mg/L).

Conversion factors to international system (SI) units are as follows: 1 ng/mL = 2.247 picomole

(pmol)/L for ferritin and 1 mg/L = 0.085 nanomole (nmol)/L for sTfR.

The most widely used methods to measure both serum ferritin and sTfR are immunoassay-based

(ELISA, immuno-turbidimetry, immunonephelometry) (Worwood 2002a; Worwood 2002b). A

WHO-supported international reference material from the United Kingdom National Institute for

Biological Standards and Control (NIBSC) has been available for ferritin for several years (94/572);

it has helped to improve the comparability of commercial kit assays. On the other hand, commercial

kit assays for sTfR produce different results, making the use of assay-specific reference intervals and
302 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

cutoff values necessary (Beard 2007). Recently, the WHO supported the development of a reference

reagent for sTfR by the NIBSC, and material 07-202 was released in 2010. It is hoped that this

material will be used by manufacturers to standardize sTfR assays and promote the establishment of

cutoff values used to assess the iron status of populations (Thorpe 2010).

Data in NHANES. Monitoring the iron status of the U.S. population has been an important

component since the inception of NHANES in 1971, and each NHANES has included a battery

of hematologic and biochemical indicators of iron status (Looker 1995). Since NHANES II (1976–

1980), models that employ multiple biochemical iron-status indicators have been used to define

iron deficiency in the population (Pilch 1984). The ferritin model (also known as the three-indicator

model), using serum ferritin, transferrin saturation, and erythrocyte protoporphyrin, was developed

in 1980 and applied to NHANES III (1988–1994) as well as to the first few years of the continuous

NHANES survey beginning in 1999. Prevalence estimates of iron deficiency using the three-indicator

model were similar in NHANES III (Looker 1997) and in NHANES 1999–2000 (Looker 2002).

Starting in 2003, NHANES limited the population of interest to children (1–5 years) and women

of childbearing age (12–49 years). Furthermore, the measurement of serum sTfR was introduced,

which allows the evaluation of iron status by the body iron model developed by Cook et al.

(2003). Using data for children and non-pregnant women from NHANES 2003–2006, Cogswell

et al. compared the new body iron model to the previously used ferritin model (2009). The

agreement between the two models was fair to good. Among non-pregnant women, the body iron

model produced lower estimates of iron deficiency prevalence and better predicted anemia. The

body iron model appeared to be less affected by inflammation than the ferritin model.

Two national health objectives that relate to iron deficiency reduction are part of the objectives for

Healthy People 2020: Objective NWS HP2020-21 (reduce iron deficiency among young children

and females of childbearing age) and Objective NWS HP2020-22 (reduce iron deficiency among

pregnant females) (http://www.healthypeople.gov/HP2020/). To provide data for these objectives,

NHANES continues with periodic monitoring of iron status in the population groups of interest.

Ferritin and sTfR data presented in this report were generated by use of commercial assay kits. Serum

ferritin was first measured by use of the BioRad QuantImune immunoradiometric assay (1999–

2003), then by use of the Roche TinaQuant immunoturbidimetric assay on the Hitachi 912 clinical

analyzer (2004–2006). The public release data file for 2003–2004 has already been adjusted to the

new assay. We used adjustment equations provided in the analytical note for data from 1999–2002

to make the data comparable to the new assay (http://www.cdc.gov/nchs/nhanes/nhanes2003-2004/

L06TFR_C.htm#Analytic_Notes). Serum sTfR was measured with the Roche immunoturbidimetric

assay on the Hitachi 912 clinical analyzer (2003–2006). We calculated body iron by using the

following formula (Cook 2003): body iron (mg/kg) = -[log10 (sTfR * 1000 / ferritin) – 2.8229] /

0.1207. The sTfR concentration in this formula represents an adjusted concentration to make the

Roche sTfR concentrations equivalent to the Flowers assay (1989) used in the development of the

body iron model: Flowers sTfR = 1.5 * Roche sTfR + 0.35 mg/L (Pfeiffer 2007).

To estimate the prevalence of low serum ferritin concentrations, we used the generally accepted

cutoff values mentioned above: 12 ng/mL for children 1-5 years of age and 15 ng/mL for women

of childbearing age and males 6 years and older. To estimate the prevalence of high serum ferritin

concentrations, we also used the cutoff values mentioned above: 150 ng/mL for women 12-49 years

of age and 200 ng/mL for men 12 years and older. Due to the lack of generally accepted cutoff

values for serum sTfR, we used the manufacturer provided assay-specific cutoff value of 4.4 mg/L to

estimate the prevalence of high sTfR concentrations in women of childbearing age. The prevalence

of low body iron (< 0 mg/kg) is indicative of the extent of iron deficiency in the population.
 

For more information about iron
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a 

b b 

a 

a 

b 

0 

4 

8 

12 

16 

20 

Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Iron deficiency prevalence (%) 

Children 1-5 years Women 12-49 years 

0 

5 

10 

15 

20 

25 

Serum ferritin 

< 15 ng/mL 

Serum sTfR 

> 4.4 mg/L 

Serum body iron stores

< 0 mg/kg 

Prevalence (%) 

Figure H.3.a. Age-adjusted prevalence estimates of low body iron stores 

(< 0 mg/kg) in U.S. children and women by race/ethnicity, National 

Health and Nutrition Examination Survey, 2003–2006. 

Error bars represent 95% confidence intervals. Bars not sharing a common letter 

differ within children and women (p < 0.05). Age adjustment was done using 

direct standardization. 

igure H.3.b. Prevalence estimates of low serum ferritin, high serum 

oluble transferrin receptor, and low serum body iron in U.S. women 

2–49 years of age, National Health and Nutrition Examination Survey, 

003–2006. 

rror bars represent 95% confidence intervals. 

F 

s 

1 

2 

E 

3. Trace Elements 303
304 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Women were at risk for iron deficiency, while men were at risk for iron excess, as can be seen from

the large differences in the prevalence of low and high serum ferritin concentrations between men

and women (Figure H.3.c). During NHANES 1999–2002, the prevalence of low serum ferritin

concentrations (< 15 ng/mL) was much lower in 12–49 year-old men (1%) than in 12–49 yearold women (13%). Conversely, the prevalence of high serum ferritin concentrations (> 200 ng/

mL for men and > 150 ng/mL for women) was much higher in men (29%) than in women (6%).

NHANES 2003–2006 showed similar prevalence estimates for women as were seen in 1999–

2002. No data are available for men in 2003–2006.

Figure H.3.c. Age-adjusted prevalence estimates of low (< 15 ng/mL) and high serum ferritin (> 200 ng/mL for men and > 150 ng/

mL for women) in U.S. men and women aged 12–49 years, National Health and Nutrition Examination Survey, 1999–2006.

Error bars represent 95% confidence intervals. Within each ferritin status category, bars not sharing a common letter differ (p < 0.05). Age adjustment 

was done using direct standardization.

Serum ferritin has been assessed as part of NHANES for many years, allowing for the evaluation

of temporal changes in concentrations. Overall, there were only minor changes in serum ferritin

concentrations in women of childbearing age over a period of almost two decades (Figure H.3.d).

Age-adjusted mean serum ferritin concentrations in women of childbearing age were slightly

lower (< 10%) in 1999–2002 and 2003–2006 than in 1988–1994. We observed the same pattern

for non-Hispanic white women, while serum ferritin concentrations decreased further during

2003–2006 for non-Hispanic black women. Mexican-American women had lower serum ferritin

concentrations in 1999–2002 than in 1988–1994, but concentrations in 2003–2006 did not

differ from concentrations in the two previous time periods.

a 

b 

b 

a 

b b 

0 

4 

8 

12 

16 

20 

24 

28 

32 

36 

Men 

1999-2002 

Women 

1999-2002 

Women 

2003-2006 

Men 

1999-2002 

Women 

1999-2002 

Women 

2003-2006 

Prevalence (%) 

Low serum ferritin High serum ferritin 
3. Trace Elements 305

Figure H.3.d. Age-adjusted geometric mean concentrations of serum ferritin in U.S. women aged 12–49 years by race/ethnicity, 

National Health and Nutrition Examination Survey, 1988–2006. 

Error bars represent 95% confidence intervals. Within a demographic group, bars not sharing a common letter differ (p < 0.05). Age adjustment was 

done using direct standardization.

Detailed Observations

The selected observations mentioned below are derived from the tables and figures presented next.

Statements about categorical differences between demographic groups noted below are based on

non-overlapping confidence limits from univariate analysis without adjusting for demographic

variables (e.g., age, sex, race/ethnicity) or other determinants of these blood concentrations (e.g.,

dietary intake, supplement usage, smoking, BMI). A multivariate analysis may alter the size

and statistical significance of these categorical differences. Furthermore, additional significant

differences of smaller magnitude may be present despite their lack of mention here (e.g., if

confidence limits slightly overlap or if differences are not statistically significant before covariate

adjustment has occurred). For a selection of citations of descriptive NHANES papers related to

these biochemical indicators of diet and nutrition, see Appendix G.

Geometric/arithmetic mean concentrations (NHANES 2003–2006):

•	 The distribution of body iron was reasonably symmetric and for that reason we present

arithmetic means.

•	 Serum ferritin concentrations increased with age (Table 3.1.a.1 and Figure 3.1.a).

•	 sTfR concentrations were highest in children than for both adolescent and adult women

(Table 3.2.a.1 and Figure 3.2.a).

•	 Body iron was lowest in children, intermediate in adolescent women, and highest in

adult women (Table 3.3.a.1 and Figure 3.3.a).

•	 Non-Hispanic whites had higher serum ferritin concentrations than Mexican

Americans, and non-Hispanic blacks had intermediate concentrations (Table 3.1.a.1).

•	 Non-Hispanic whites had lower sTfR concentrations than Mexican Americans, who had

lower concentrations still than non-Hispanic blacks (Table 3.2.a.1).

•	 Non-Hispanic whites had higher body iron than the other two race/ethnic groups

(Table 3.3.a.1).

0 

10 

20 

30 

40 

50 

60 

Total population Mexican American NonHispanic black NonHispanic white 

Serum ferritin (ng/mL) 

1988-1994 

1999-2002 

2003-2006 

a

b

b

a

b

a,b

a

b

a

b b

c
306 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Changes in geometric/arithmetic mean concentrations across survey cycles:

•	 All three iron status indicators remained stable across the survey cycles measured: serum

ferritin geometric mean concentrations (Table 3.1.b) between 1999 and 2006; sTfR

geometric mean concentrations (Table 3.2.b) and body iron arithmetic means (Table

3.3.b) between 2003 and 2006.

Prevalence estimates of low or high biochemical indicator concentrations:

•	 In 2003–2006, approximately 9% of children (1–5 years) (Table 3.1.c.1) had serum

ferritin concentrations < 12 ng/mL and 14% of women (12–49 years) had serum

ferritin concentrations < 15 ng/mL (Table 3.1.c.2). Approximately 5% of women

(12–49 years) (Table 3.1.c.3) had high serum ferritin concentrations (> 150 ng/mL),

indicating severe risk of iron overload.

•	 The prevalence of low serum ferritin concentrations did not change between 1999 and

2006 in children (Table 3.1.d.1) and women of childbearing age (Table 3.1.d.2), nor

between 1999 and 2002 in males 6 years and older (Table 3.1.d.3). The prevalence of

high serum ferritin concentrations also remained constant between 1999 and 2006 in

women of childbearing age (Table 3.1.d.4) and between 1999–2002 in men 12 years

and older (Table 3.1.d.5).

•	 In 2003–2006, approximately 19% of women (12–49 years) had serum sTfR

concentrations > 4.4 mg/L (Table 3.2.c), and the prevalence was the same in both

survey cycles (Table 3.2.d).

•	 Less than 10% of children (8% of boys and 5% of girls 1–5 years) and 10% of women

(12–49 years) had negative body iron balance, indicative of iron deficiency (Tables

3.3.c.1 and 3.3.c.2), and the prevalence was the same in both survey cycles (Tables

3.3.d.1 and 3.3.d.2).
3. Trace Elements 307
308

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.1.a.1. Serum ferritin: Concentrations

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for children aged 1–5 years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total 35.7 (34.4 – 37.1) 4.65 (4.52 – 4.78) 6.99 (6.15 – 7.71) 36.2 (34.7 – 38.1) 143 (133 – 157) 194 (177 – 210) 6,012

(Children 1–5 years women 12–49 years),

Age group1–5 years (Children) 26.2 (25.2 – 27.3) 6.68 (5.19 – 7.72) 9.14 (7.87 – 9.82) 26.7 (25.5 – 27.9) 65.6 (59.6 – 68.1) 77.5 (70.2 – 91.4) 1,482

12–19 years (Women) 29.3 (27.7 – 30.9) 4.64 (4.31 – 4.98) 6.83 (5.19 – 7.77) 31.9 (29.9 – 33.3) 81.4 (76.7 – 92.2) 103 (91.8 – 134) 1,991

20–39 years (Women) 38.1 (36.1 – 40.2) 4.67 (4.45 – 4.88) 7.19 (5.66 – 8.21) 40.5 (38.3 – 43.3) 135 (114 – 159) 176 (153 – 206) 1,780

40–49 years (Women) 43.2 (39.0 – 47.7) 4.38 (4.06 – 4.69) 5.81 (4.73 – 7.10) 45.9 (40.5 – 50.7) 211 (184 – 262) 264 (231 – 317) 759

GenderMales (1–5 years) 26.2 (24.9 – 27.7) 6.90 (4.61 – 7.90) 8.90 (8.01 – 9.68) 26.9 (25.1 – 28.5) 63.6 (56.9 – 70.7) 77.9 (67.7 – 111) 757

Females (1–5, 12–49 years) 36.6 (35.2 – 38.1) 4.62 (4.48 – 4.75) 6.80 (5.96 – 7.56) 38.1 (36.0 – 39.4) 145 (136 – 165) 198 (180 – 219) 5,255

Race/ethnicity(Children 1–5 years, women 12–49 years)Mexican Americans 30.2 (27.5 – 33.1) 4.18 (3.78 – 4.43) 4.87 (4.62 – 5.46) 31.7 (28.7 – 34.0) 121 (101 – 161) 166 (140 – 231) 1,704

Non-Hispanic Blacks 33.5 (31.4 – 35.7) 4.13 (3.31 – 4.70) 5.49 (4.69 – 6.46) 33.7 (31.8 – 35.8) 165 (133 – 201) 212 (182 – 261) 1,676

Non-Hispanic Whites 37.5 (35.5 – 39.6) 4.89 (4.66 – 5.44) 8.07 (6.52 – 8.85) 38.2 (35.9 – 39.8) 143 (131 – 159) 194 (172 – 233) 2,089
1−5 12−19 20−39 40−49 

0 20 40 60 80 

Serum ferritin

(ng/mL) 

Overall 

1−5 12−19 20−39 40−49 

Mexican Americans 

Females 

Males 

80 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 3.1. a . Serum ferritin: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Serum ferritin Serum ferritin (ng/mL) (ng/mL) 0 20 40 60 80 0 20 40 60 

1−5 12−19 20−39 40−49 1−5 12−19 20−39 40−49 

Females Males 

1−5 12−19 20−39 40−49 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

1−5 12−19 20−39 40−49 

3. Trace Elements 309
310 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.1.a.2. Serum ferritin: Total population

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for children aged 1–5 years and 

women aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 35.7 (34.4 – 37.1) 6.99 (6.15 – 7.71) 36.2 (34.7 – 38.1) 143 (133 – 157) 6,012

1–5 years 26.2 (25.2 – 27.3) 9.14 (7.87 – 9.82) 26.7 (25.5 – 27.9) 65.6 (59.6 – 68.1) 1,482

Males

1–5 years 26.2 (24.9 – 27.7) 8.90 (8.01 – 9.68) 26.9 (25.1 – 28.5) 63.6 (56.9 – 70.7) 757

Females

Total, 1–5, 12–49 years 36.6 (35.2 – 38.1) 6.80 (5.96 – 7.56) 38.1 (36.0 – 39.4) 145 (136 – 165) 5,255

1–5 years 26.3 (24.9 – 27.7) 9.29 (6.81 – 10.1) 26.5 (24.8 – 28.0) 67.0 (59.2 – 74.3) 725

12–19 years 29.3 (27.7 – 30.9) 6.83 (5.19 – 7.77) 31.9 (29.9 – 33.3) 81.4 (76.7 – 92.2) 1,991

20–39 years 38.1 (36.1 – 40.2) 7.19 (5.66 – 8.21) 40.5 (38.3 – 43.3) 135 (114 – 159) 1,780

40–49 years 43.2 (39.0 – 47.7) 5.81 (4.73 – 7.10) 45.9 (40.5 – 50.7) 211 (184 – 262) 759

Table 3.1.a.3. Serum ferritin: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for Mexican-American children 

aged 1–5 years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination 

Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 30.2 (27.5 – 33.1) 4.87 (4.62 – 5.46) 31.7 (28.7 – 34.0) 121 (101 – 161) 1,704

1–5 years 24.5 (22.8 – 26.3) 6.44 (4.69 – 7.69) 25.5 (23.5 – 27.6) 68.9 (57.7 – 83.3) 468

Males

1–5 years 23.5 (21.3 – 25.9) 6.04 (4.33 – 7.21) 24.6 (23.1 – 27.0) 63.8 (52.5 – 118) 225

Females

Total, 1–5, 12–49 years 31.0 (28.0 – 34.5) 4.84 (4.59 – 5.33) 33.2 (29.3 – 36.1) 126 (104 – 167) 1,479

1–5 years 25.5 (23.6 – 27.6) 6.81 (4.56 – 9.78) 26.7 (23.2 – 29.8) 69.6 (60.7 – 88.6) 243

12–19 years 26.6 (24.8 – 28.5) 6.35 (4.85 – 7.38) 27.3 (25.5 – 29.2) 89.6 (80.6 – 97.3) 647

20–39 years 33.7 (29.2 – 38.9) 4.89 (4.62 – 5.51) 37.1 (31.6 – 43.9) 139 (106 – 213) 434

40–49 years 33.1 (25.7 – 42.7) 4.27† (3.48 – 4.66) 34.3 (28.3 – 42.9) 170† (134 – 262) 155

† Estimate is subject to greater uncertainty due to small cell size. 
3. Trace Elements 311

Table 3.1.a.4. Serum ferritin: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for non-Hispanic black children 

aged 1–5 years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination 

Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 33.5 (31.4 – 35.7) 5.49 (4.69 – 6.46) 33.7 (31.8 – 35.8) 165 (133 – 201) 1,676

1–5 years 30.8 (28.9 – 32.8) 11.4 (9.51 – 14.2) 30.7 (28.7 – 32.7) 72.5 (65.8 – 88.9) 429

Males

1–5 years 30.0 (27.3 – 32.9) 10.6† (5.39 – 14.4) 29.6 (26.6 – 33.4) 66.2† (58.1 – 96.6) 218

Females

Total, 1–5, 12–49 years 33.8 (31.5 – 36.2) 5.26 (4.56 – 6.25) 34.1 (32.1 – 36.9) 171 (139 – 207) 1,458

1–5 years 31.7 (29.8 – 33.7) 12.4† (9.78 – 14.6) 31.6 (29.1 – 33.6) 75.8† (67.6 – 89.4) 211

12–19 years 28.2 (25.5 – 31.2) 6.61 (4.97 – 7.55) 31.1 (27.4 – 33.7) 88.7 (79.4 – 104) 674

20–39 years 30.1 (27.9 – 32.4) 5.02 (4.22 – 6.08) 31.1 (28.4 – 34.1) 132 (122 – 173) 375

40–49 years 49.6 (40.4 – 61.0) 4.31† (< LOD – 8.31) 53.5 (42.2 – 63.9) 257† (207 – 531) 198

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 

Table 3.1.a.5. Serum ferritin: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for non-Hispanic white children 

aged 1–5 years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination 

Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 37.5 (35.5 – 39.6) 8.07 (6.52 – 8.85) 38.2 (35.9 – 39.8) 143 (131 – 159) 2,089

1–5 years 25.9 (24.2 – 27.7) 9.30 (8.13 – 10.0) 26.3 (24.4 – 28.1) 61.4 (55.7 – 67.8) 416

Males

1–5 years 26.1 (23.8 – 28.6) 9.13 (4.71 – 10.5) 27.1 (24.3 – 29.7) 56.9 (53.5 – 89.4) 229

Females

Total, 1–5, 12–49 years 38.5 (36.3 – 40.7) 7.96 (6.36 – 8.78) 39.4 (37.2 – 41.0) 144 (135 – 167) 1,860

1–5 years 25.6 (23.4 – 27.9) 9.40† (5.96 – 10.3) 25.5 (23.4 – 27.8) 63.7† (53.8 – 87.4) 187

12–19 years 30.0 (27.7 – 32.6) 6.88 (4.67 – 8.55) 33.0 (31.1 – 34.9) 78.2 (70.9 – 93.0) 520

20–39 years 41.0 (37.8 – 44.5) 8.75 (7.16 – 10.1) 42.3 (39.2 – 47.0) 134 (112 – 171) 812

40–49 years 43.6 (38.3 – 49.6) 6.61 (4.82 – 8.43) 46.1 (39.7 – 51.2) 212 (164 – 266) 341

† Estimate is subject to greater uncertainty due to small cell size. 
312 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.1.b. Serum ferritin: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in ng/mL) for children aged 1–5 and women 

aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total (Children 1–5 years, women 12–49 years)

 1999–2000 38.8 (36.7 – 41.0) 8.06 (5.23 – 9.99) 38.3 (34.7 – 42.5) 139 (129 – 173) 2,919

 2001–2002 36.1 (34.2 – 38.0) 5.23 ** 35.2 (33.2 – 37.2) 149 (136 – 175) 3,365

 2003–2004 36.4 (34.7 – 38.3) 7.70 (5.80 – 8.58) 36.1 (34.6 – 38.6) 151 (141 – 173) 2,981

 2005–2006 35.0 (32.9 – 37.2) 6.46 (5.69 – 7.19) 36.2 (33.6 – 38.7) 135 (113 – 167) 3,031

Age group

1–5 years (Children)

 1999–2000 28.7 (26.9 – 30.7) 10.6 (5.95 – 13.5) 28.2 (26.0 – 31.6) 74.6 (57.9 – 94.2) 680

 2001–2002 27.9 (25.6 – 30.5) 6.43 (5.23 – 9.79) 28.2 (26.2 – 30.4) 78.6 (68.5 – 105) 843

 2003–2004 25.2 (23.7 – 26.8) 9.27 (8.08 – 9.76) 24.9 (23.2 – 26.7) 64.0 (57.0 – 67.8) 796

 2005–2006 27.6 (26.0 – 29.2) 8.95 (7.95 – 9.78) 28.5 (27.4 – 30.1) 66.7 (63.2 – 77.2) 686

12–19 years (Women)

 1999–2000 32.5 (29.6 – 35.8) 9.26 (5.23 – 10.4) 32.8 (29.6 – 37.1) 83.3 (79.4 – 99.7) 1,048

 2001–2002 30.1 (28.5 – 31.9) 6.55 (5.23 – 8.62) 32.5 (29.9 – 33.7) 84.5 (79.3 – 95.6) 1,120

 2003–2004 28.0 (25.5 – 30.7) 6.11 (4.43 – 7.97) 30.1 (27.9 – 32.7) 86.4 (75.6 – 102) 998

 2005–2006 30.6 (28.6 – 32.8) 7.21 (5.52 – 8.79) 33.4 (30.9 – 35.7) 79.0 (75.0 – 94.0) 993

20–39 years (Women)

 1999–2000 40.0 (36.0 – 44.4) 5.23 ** 43.5 (36.3 – 52.2) 137 (118 – 187) 838

 2001–2002 37.8 (35.2 – 40.5) 5.23 ** 38.3 (34.5 – 41.7) 142 (119 – 192) 992

 2003–2004 39.8 (37.1 – 42.7) 8.40 (7.52 – 9.20) 41.1 (39.2 – 44.6) 132 (111 – 172) 822

 2005–2006 36.5 (33.5 – 39.9) 5.60 (4.70 – 7.17) 39.2 (34.1 – 44.6) 135 (110 – 179) 958

40–49 years (Women)

 1999–2000 50.3 (43.6 – 57.9) 9.15 (5.23 – 12.1) 50.0 (42.8 – 59.8) 227 (202 – 275) 353

 2001–2002 43.7 (39.3 – 48.6) 5.23 ** 46.5 (39.2 – 53.9) 221 (195 – 249) 410

 2003–2004 46.6 (39.9 – 54.4) 5.16 (4.21 – 8.44) 47.1 (43.5 – 53.6) 227 (197 – 317) 365

 2005–2006 40.0 (34.5 – 46.3) 6.26 (4.89 – 6.96) 41.6 (34.0 – 51.7) 169 (144 – 264) 394

Gender

Males (1–5 years)

 1999–2000 27.4 (25.4 – 29.6) 10.8 (6.11 – 13.1) 26.6 (24.7 – 28.4) 73.7 (55.4 – 95.7) 377

 2001–2002 26.1 (23.4 – 29.0) 5.23 ** 27.4 (24.4 – 30.3) 77.9 (67.2 – 112) 428

 2003–2004 25.0 (23.1 – 27.1) 9.19 (6.68 – 10.2) 24.8 (22.5 – 27.0) 57.3 (55.3 – 67.6) 415

 2005–2006 27.8 (25.8 – 29.9) 8.71 (8.18 – 9.54) 29.3 (26.9 – 31.0) 70.4 (55.8 – 105) 342

Females (1–5, 12–49 years)

 1999–2000 40.0 (37.7 – 42.5) 7.86 (5.23 – 9.85) 40.8 (37.0 – 45.1) 146 (132 – 179) 2,542

 2001–2002 37.0 (35.2 – 38.9) 5.23 ** 36.3 (34.5 – 38.3) 157 (141 – 186) 2,937

 2003–2004 37.7 (35.6 – 39.8) 7.60 (5.49 – 8.51) 38.7 (36.0 – 40.1) 158 (143 – 186) 2,566

 2005–2006 35.6 (33.4 – 37.9) 6.31 (5.46 – 7.04) 37.2 (34.2 – 40.0) 137 (115 – 176) 2,689

Race/ethnicity (Children 1–5 years, women 12–49 years)

Mexican Americans

 1999–2000 29.0 (26.6 – 31.6) 5.23 ** 30.2 (27.9 – 32.7) 117 (81.2 – 179) 1,077

 2001–2002 27.9 (25.6 – 30.4) 5.23 ** 28.9 (26.8 – 31.3) 102 (82.4 – 162) 967

 2003–2004 32.0 (27.4 – 37.4) 6.36 (4.30 – 7.98) 33.2 (28.1 – 36.8) 140 (98.8 – 203) 793

 2005–2006 28.4 (25.7 – 31.4) 4.57 (4.01 – 5.22) 29.7 (27.6 – 32.9) 106 (98.4 – 119) 911

Non-Hispanic Blacks

 1999–2000 38.5 (34.3 – 43.3) 5.23 ** 38.1 (33.1 – 44.9) 171 (130 – 382) 690

 2001–2002 35.8 (31.0 – 41.3) 5.23 ** 36.1 (32.7 – 40.2) 187 (138 – 263) 855

 2003–2004 34.1 (30.5 – 38.2) 5.74 (4.17 – 7.50) 33.1 (30.0 – 36.9) 172 (127 – 267) 870

 2005–2006 32.7 (30.5 – 35.1) 5.35 (4.67 – 6.15) 34.3 (31.1 – 38.1) 145 (127 – 179) 806

Non-Hispanic Whites

 1999–2000 41.1 (38.4 – 44.0) 9.77 (5.23 – 12.4) 41.0 (35.1 – 47.1) 146 (131 – 181) 838

 2001–2002 37.0 (34.2 – 40.1) 6.86 (5.23 – 8.38) 35.5 (32.8 – 38.6) 141 (124 – 188) 1,236

 2003–2004 37.7 (35.1 – 40.5) 8.37 (4.79 – 10.0) 38.3 (35.6 – 39.7) 147 (136 – 190) 1,069

 2005–2006 37.3 (34.1 – 40.7) 7.57 (6.33 – 8.68) 38.1 (34.4 – 41.1) 135 (113 – 176) 1,020

** The minimum value is reported. The desired percentile does not exist because it is less than the estimated cumulative distribution evaluated at the minimum.
400 

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99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 1−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(M/F 1−5y, (F) (F) (1−5y) (1−5, (M/F 1−5y, (M/F 1−5y, (M/F 1−5y, 

F 12−49y) 12−49y) F 12−49y) F 12−49y) F 12−49y) 

Figure 3.1.b. Serum ferritin: Concentrations by survey cycle 

Selected percentiles in ng/mL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006 

3. Trace Elements 313
314 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.1.c.1. Serum ferritin: Prevalence

Prevalence (in percent) of low serum ferritin concentration (< 12 ng/mL) for children in the U.S. 

population aged 1–5 years, National Health and Nutrition Examination Survey, 2003–2006.

Sample

size

Prevalence

(95% conf. interval)

Estimated total

number of persons

Children, 1–5 years 1,482 8.9 (7.1 – 11.2) 1,810,000

Gender

Males 757 9.2 (7.1 – 11.9) 953,000

Females 725 8.6 (6.2 – 11.8) 855,000

Race/ethnicity

Mexican Americans 468 11.4 (8.6 – 15.1) 348,000

Non-Hispanic Blacks 429 4.9 (3.1 – 7.8) 148,000

Non-Hispanic Whites 416 9.8 (6.9 – 13.7) 1,134,000
3. Trace Elements 315

Table 3.1.c.2. Serum ferritin: Prevalence

Prevalence (in percent) of low serum ferritin concentration (< 15 ng/mL) for women in the U.S. 

population aged 12–49 years, National Health and Nutrition Examination Survey, 2003–2006. 

Sample

size

Prevalence

(95% conf. interval)

Estimated total

number of persons

Women, 12–49 years 4,530 13.6 (12.2 – 15.2) 10,748,000

Age group

12–19 years 1,991 15.2 (12.4 – 18.4) 2,462,000

20–49 years 2,539 13.2 (11.8 – 14.8) 8,299,000

Race/ethnicity

Mexican Americans 1,236 18.6 (14.9 – 23.0) 1,427,000

Non-Hispanic Blacks 1,247 19.9 (17.9 – 22.1) 2,140,000

Non-Hispanic Whites 1,673 11.3 (9.2 – 13.9) 5,805,000
316 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.1.c.3. Serum ferritin: Prevalence

Prevalence (in percent) of high serum ferritin concentration (> 150 ng/mL) for women in the U.S. 

population aged 12–49 years, National Health and Nutrition Examination Survey, 2003–2006. 

Sample

size

Prevalence

(95% conf. interval)

Estimated total

number of persons

Women, 12–49 years 4,530 5.2 (4.2 – 6.4) 4,086,000

Age group

12–19 years 1,991 0.9‡ (0.5 – 1.8) 149,000‡

20–49 years 2,539 6.2 (5.0 – 7.7) 3,900,000

Race/ethnicity

Mexican Americans 1,236 4.2 (2.5 – 7.2) 324,000

Non-Hispanic Blacks 1,247 7.1 (5.0 – 9.9) 759,000

Non-Hispanic Whites 1,673 4.9 (3.7 – 6.3) 2,495,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.
3. Trace Elements 317

Table 3.1.d.1. Serum ferritin: Prevalence by survey cycle

Prevalence (in percent) of low serum ferritin concentration (< 12 ng/mL) for children in the U.S. population 

aged 1–5 years, National Health and Nutrition Examination Survey, 1999–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Children, 1–5 years

 1999–2000 680 5.7 (3.3 – 9.6) 1,133,000

 2001–2002 843 10.0 (7.0 – 13.9) 1,935,000

 2003–2004 796 9.0 (6.6 – 12.3) 1,828,000

 2005–2006 686 8.8 (6.0 – 12.8) 1,782,000

Gender

Males

 1999–2000 377 5.9 (3.3 – 10.4) 599,000

 2001–2002 428 13.3 (8.6 – 20.1) 1,326,000

 2003–2004 415 9.4 (6.6 – 13.3) 970,000

 2005–2006 342 9.0 (5.8 – 13.8) 933,000

Females

 1999–2000 303 5.5‡ (2.4 – 12.0) 530,000‡

 2001–2002 415 6.5 (4.3 – 9.6) 613,000

 2003–2004 381 8.6 (5.6 – 12.8) 854,000

 2005–2006 344 8.6 (4.8 – 14.9) 849,000

Race/ethnicity

Mexican Americans

 1999–2000 269 11.7 (7.7 – 17.4) 305,000

 2001–2002 246 10.1 (7.4 – 13.6) 283,000

 2003–2004 230 12.5 (7.6 – 19.8) 380,000

 2005–2006 238 10.2 (8.1 – 12.8) 329,000

Non-Hispanic Blacks

 1999–2000 168 4.7 (2.6 – 8.4) 142,000

 2001–2002 247 § §

 2003–2004 252 6.0 (3.1 – 11.3) 180,000

 2005–2006 177 3.4‡ (1.7 – 6.9) 100,000‡

Non-Hispanic Whites

 1999–2000 161 2.9‡ (1.3 – 6.1) 346,000‡

 2001–2002 259 11.9 (7.1 – 19.2) 1,357,000

 2003–2004 230 9.4 (5.5 – 15.5) 1,088,000

 2005–2006 186 10.3 (6.1 – 16.7) 1,157,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
318 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.1.d.2. Serum ferritin: Prevalence by survey cycle

Prevalence (in percent) of low serum ferritin concentration (< 15 ng/mL) for women in the U.S. population 

aged 12–49 years, National Health and Nutrition Examination Survey, 1999–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Women, 12–49 years

 1999–2000 2,239 11.4 (9.4 – 13.9) 8,767,000

 2001–2002 2,522 13.9 (12.2 – 15.8) 10,821,000

 2003–2004 2,185 13.2 (10.7 – 16.3) 10,460,000

 2005–2006 2,345 14.0 (12.6 – 15.5) 11,069,000

Age group

12–19 years

 1999–2000 1,048 11.5 (8.5 – 15.3) 1,781,000

 2001–2002 1,120 13.9 (11.2 – 17.1) 2,201,000

 2003–2004 998 17.4 (12.8 – 23.3) 2,825,000

 2005–2006 993 12.9 (10.0 – 16.5) 2,119,000

20–49 years

 1999–2000 1,191 11.4 (9.2 – 14.2) 6,986,000

 2001–2002 1,402 13.9 (12.0 – 16.0) 8,620,000

 2003–2004 1,187 12.2 (9.7 – 15.2) 7,670,000

 2005–2006 1,352 14.2 (12.8 – 15.7) 8,938,000

Race/ethnicity

Mexican Americans

 1999–2000 808 18.8 (12.3 – 27.5) 1,140,000

 2001–2002 721 21.9 (18.8 – 25.4) 1,541,000

 2003–2004 563 16.7 (11.7 – 23.2) 1,276,000

 2005–2006 673 20.6 (15.3 – 27.2) 1,632,000

Non-Hispanic Blacks

 1999–2000 522 16.4 (11.2 – 23.4) 1,764,000

 2001–2002 608 19.5 (12.3 – 29.6) 2,091,000

 2003–2004 618 19.1 (16.4 – 22.0) 2,051,000

 2005–2006 629 20.7 (17.5 – 24.4) 2,256,000

Non-Hispanic Whites

 1999–2000 677 9.1 (6.7 – 12.2) 4,741,000

 2001–2002 977 11.6 (9.5 – 14.2) 6,025,000

 2003–2004 839 11.8 (8.3 – 16.5) 6,032,000

 2005–2006 834 10.9 (8.5 – 13.8) 5,500,000
3. Trace Elements 319

Table 3.1.d.3. Serum ferritin: Prevalence by survey cycle

Prevalence (in percent) of low serum ferritin concentration (< 15 ng/mL) for males in the U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 1999–2002. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Males, 6 years and older

 1999–2000 3,488 1.1 (0.6 – 2.0) 1,323,000

 2001–2002 3,849 1.3 (0.9 – 1.7) 1,576,000

Age group

6–11 years

 1999–2000 463 § §

 2001–2002 509 § §

12–19 years

 1999–2000 1,078 2.1‡ (1.0 – 4.2) 336,000‡

 2001–2002 1,094 2.8‡ (1.4 – 5.4) 463,000‡

20–39 years

 1999–2000 632 § §

 2001–2002 724 0.5‡ (0.2 – 1.0) 176,000‡

40–59 years

 1999–2000 570 § §

 2001–2002 770 § §

60 years and older

 1999–2000 745 § §

 2001–2002 752 2.0 (1.1 – 3.4) 384,000

Race/ethnicity

Mexican Americans

 1999–2000 1,196 1.0 (0.5 – 1.8) 91,000

 2001–2002 958 0.7‡ (0.3 – 1.5) 77,000‡

Non-Hispanic Blacks

 1999–2000 781 § §

 2001–2002 921 1.3‡ (0.7 – 2.7) 187,000‡

Non-Hispanic Whites

 1999–2000 1,223 1.3‡ (0.6 – 2.7) 1,100,000‡

 2001–2002 1,678 1.3 (0.9 – 1.9) 1,159,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate. 

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate. 
320 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.1.d.4. Serum ferritin: Prevalence by survey cycle

Prevalence (in percent) of high serum ferritin concentration (> 150 ng/mL) for women in the U.S. population 

aged 12–49 years, National Health and Nutrition Examination Survey, 1999–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Women, 12–49 years

 1999–2000 2,239 5.3 (4.0 – 7.0) 4,069,000

 2001–2002 2,522 5.6 (4.5 – 7.0) 4,374,000

 2003–2004 2,185 6.0 (4.7 – 7.5) 4,711,000

 2005–2006 2,345 4.4 (2.9 – 6.6) 3,470,000

Age group

12–19 years

 1999–2000 1,048 § §

 2001–2002 1,120 § §

 2003–2004 998 § §

 2005–2006 993 1.4‡ (0.6 – 3.2) 237,000‡

20–49 years

 1999–2000 1,191 6.3 (4.8 – 8.3) 3,878,000

 2001–2002 1,402 6.8 (5.3 – 8.5) 4,196,000

 2003–2004 1,187 7.3 (5.9 – 9.1) 4,600,000

 2005–2006 1,352 5.1 (3.2 – 7.9) 3,202,000

Race/ethnicity

Mexican Americans

 1999–2000 808 3.7‡ (1.7 – 7.9) 224,000‡

 2001–2002 721 3.5 (1.8 – 6.8) 249,000

 2003–2004 563 5.6‡ (2.7 – 11.3) 429,000‡

 2005–2006 673 2.9‡ (1.4 – 5.7) 226,000‡

Non-Hispanic Blacks

 1999–2000 522 7.8 (5.2 – 11.6) 840,000

 2001–2002 608 7.7 (5.0 – 11.8) 828,000

 2003–2004 618 8.3 (4.6 – 14.7) 895,000

 2005–2006 629 5.7 (4.2 – 7.9) 625,000

Non-Hispanic Whites

 1999–2000 677 5.7 (4.1 – 8.0) 3,000,000

 2001–2002 977 5.0 (3.4 – 7.2) 2,579,000

 2003–2004 839 5.7 (4.1 – 7.8) 2,926,000

 2005–2006 834 4.0 (2.5 – 6.3) 2,026,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate.

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate.
3. Trace Elements 321

Table 3.1.d.5. Serum ferritin: Prevalence by survey cycle

Prevalence (in percent) of high serum ferritin concentration (> 200 ng/mL) for males in the U.S. population 

aged 12 years and older, National Health and Nutrition Examination Survey, 1999–2002. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Males, 12 years and older

 1999–2000 3,025 31.8 (27.7 – 36.3) 34,391,000

 2001–2002 3,340 32.7 (30.1 – 35.5) 36,644,000

Age group

12–19 years

 1999–2000 1,078 3.3 (1.8 – 6.0) 538,000

 2001–2002 1,094 1.7 (1.0 – 2.9) 283,000

20–39 years

 1999–2000 632 33.1 (26.8 – 40.1) 12,720,000

 2001–2002 724 31.0 (27.1 – 35.1) 12,101,000

40–59 years

 1999–2000 570 39.9 (33.0 – 47.1) 13,748,000

 2001–2002 770 44.5 (39.0 – 50.2) 16,443,000

60 years and older

 1999–2000 745 39.1 (33.2 – 45.2) 7,336,000

 2001–2002 752 37.2 (32.3 – 42.4) 7,219,000

Race/ethnicity

Mexican Americans

 1999–2000 998 27.4 (23.1 – 32.1) 2,155,000

 2001–2002 819 25.8 (21.3 – 31.0) 2,430,000

Non-Hispanic Blacks

 1999–2000 652 37.8 (32.8 – 43.2) 4,574,000

 2001–2002 746 33.7 (28.7 – 39.2) 4,079,000

Non-Hispanic Whites

 1999–2000 1,122 32.4 (27.5 – 37.6) 25,539,000

 2001–2002 1,518 33.1 (29.9 – 36.5) 26,398,000
322

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.2.a.1. Serum soluble transferrin receptor: Concentrations

Geometric mean and selected percentiles of serum concentrations (in mg/L) for children aged 1–5 years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total 3.57 (3.51 – 3.63) 1.94 (1.91 – 1.96) 2.11 (1.99 – 2.20) 3.46 (3.37 – 3.55) 6.04 (5.90 – 6.36) 7.06 (6.78 – 7.62) 5,856

(Children 1–5 years, women 12–49 years)

Age group1–5 years (Children) 4.30 (4.24 – 4.37) 2.84 (2.73 – 2.90) 2.98 (2.91 – 3.06) 4.21 (4.11 – 4.29) 6.00 (5.91 – 6.42) 6.67 (6.45 – 7.17) 1,375

12–19 years (Women) 3.50 (3.44 – 3.55) 2.12 (1.96 – 2.21) 2.27 (2.20 – 2.35) 3.38 (3.32 – 3.46) 5.36 (5.22 – 5.82) 6.47 (5.95 – 7.32) 1,968

20–39 years (Women) 3.42 (3.36 – 3.49) 1.91 (1.85 – 1.94) 2.02 (1.95 – 2.13) 3.23 (3.15 – 3.32) 6.00 (5.75 – 6.36) 6.97 (6.50 – 7.88) 1,761

40–49 years (Women) 3.52 (3.38 – 3.65) 1.91 (1.71 – 1.95) 1.97 (1.93 – 2.05) 3.35 (3.17 – 3.56) 6.43 (6.07 – 6.98) 7.96 (7.12 – 9.13) 752

GenderMales (1–5 years) 4.38 (4.28 – 4.48) 2.93 (2.75 – 2.98) 3.06 (2.95 – 3.18) 4.26 (4.13 – 4.41) 6.25 (5.94 – 6.63) 6.80 (6.48 – 7.45) 698

Females (1–5, 12–49 years) 3.51 (3.45 – 3.57) 1.93 (1.91 – 1.95) 2.07 (1.97 – 2.18) 3.37 (3.29 – 3.47) 6.02 (5.83 – 6.36) 7.19 (6.79 – 7.67) 5,158

Race/ethnicity(Children 1–5 years, women 12–49 years)Mexican Americans 3.62 (3.53 – 3.72) 1.97 (1.93 – 2.03) 2.16 (2.06 – 2.24) 3.52 (3.42 – 3.62) 6.38 (5.92 – 7.10) 7.80 (6.96 – 8.77) 1,643

Non-Hispanic Blacks 4.19 (4.10 – 4.29) 2.17 (1.97 – 2.33) 2.47 (2.31 – 2.57) 3.97 (3.91 – 4.04) 8.02 (7.31 – 9.69) 10.3 (9.78 – 12.6) 1,634

Non-Hispanic Whites 3.43 (3.35 – 3.52) 1.92 (1.89 – 1.94) 2.02 (1.94 – 2.17) 3.32 (3.22 – 3.44) 5.59 (5.28 – 6.07) 6.33 (5.96 – 7.33) 2,048
1−5 12−19 20−39 40−49 

Serum soluble transferrin

0 2 4 6 

receptor (mg/L) 

Overall 

1−5 12−19 20−39 40−49 

Mexican Americans 

Females 

Males 

6 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 3.2.a. Serum soluble transferrin receptor: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Serum soluble transferrin Serum soluble transferrin receptor (mg/L) receptor (mg/L) 0 2 4 6 0 2 4 

1−5 12−19 20−39 40−49 1−5 12−19 20−39 40−49 

Females Males 

1−5 12−19 20−39 40−49 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

1−5 12−19 20−39 40−49 

3. Trace Elements 323
324 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.2.a.2. Serum soluble transferrin receptor: Total population

Geometric mean and selected percentiles of serum concentrations (in mg/L) for children aged 1–5 years and 

women aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 3.57 (3.51 – 3.63) 2.11 (1.99 – 2.20) 3.46 (3.37 – 3.55) 6.04 (5.90 – 6.36) 5,856

1–5 years 4.30 (4.24 – 4.37) 2.98 (2.91 – 3.06) 4.21 (4.11 – 4.29) 6.00 (5.91 – 6.42) 1,375

Males

1–5 years 4.38 (4.28 – 4.48) 3.06 (2.95 – 3.18) 4.26 (4.13 – 4.41) 6.25 (5.94 – 6.63) 698

Females

Total, 1–5, 12–49 years 3.51 (3.45 – 3.57) 2.07 (1.97 – 2.18) 3.37 (3.29 – 3.47) 6.02 (5.83 – 6.36) 5,158

1–5 years 4.22 (4.12 – 4.31) 2.90 (2.83 – 3.00) 4.10 (3.99 – 4.27) 5.91 (5.68 – 6.16) 677

12–19 years 3.50 (3.44 – 3.55) 2.27 (2.20 – 2.35) 3.38 (3.32 – 3.46) 5.36 (5.22 – 5.82) 1,968

20–39 years 3.42 (3.36 – 3.49) 2.02 (1.95 – 2.13) 3.23 (3.15 – 3.32) 6.00 (5.75 – 6.36) 1,761

40–49 years 3.52 (3.38 – 3.65) 1.97 (1.93 – 2.05) 3.35 (3.17 – 3.56) 6.43 (6.07 – 6.98) 752

Table 3.2.a.3. Serum soluble transferrin receptor: Mexican Americans

Geometric mean and selected percentiles of serum concentrations (in mg/L) for Mexican-American children 

aged 1–5 years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination 

Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 3.62 (3.53 – 3.72) 2.16 (2.06 – 2.24) 3.52 (3.42 – 3.62) 6.38 (5.92 – 7.10) 1,643

1–5 years 4.30 (4.17 – 4.43) 2.99 (2.94 – 3.07) 4.15 (3.99 – 4.32) 6.40 (6.06 – 7.18) 422

Males

1–5 years 4.38 (4.21 – 4.56) 3.09† (2.90 – 3.21) 4.18 (4.00 – 4.36) 6.89† (6.00 – 8.30) 203

Females

Total, 1–5, 12–49 years 3.55 (3.45 – 3.65) 2.13 (2.01 – 2.22) 3.41 (3.27 – 3.54) 6.32 (5.85 – 7.25) 1,440

1–5 years 4.21 (4.08 – 4.35) 2.93† (2.58 – 3.07) 4.10 (3.94 – 4.31) 6.01† (5.66 – 7.53) 219

12–19 years 3.57 (3.46 – 3.68) 2.26 (2.18 – 2.36) 3.44 (3.33 – 3.59) 5.92 (5.27 – 6.92) 637

20–39 years 3.40 (3.27 – 3.54) 2.02 (1.93 – 2.12) 3.19 (3.01 – 3.40) 5.99 (5.62 – 7.63) 430

40–49 years 3.63 (3.32 – 3.96) 2.22† (1.80 – 2.30) 3.34 (3.02 – 3.71) 7.75† (6.29 – 11.7) 154

† Estimate is subject to greater uncertainty due to small cell size. 
3. Trace Elements 325

Table 3.2.a.4. Serum soluble transferrin receptor: Non-Hispanic blacks

Geometric mean and selected percentiles of serum concentrations (in mg/L) for non-Hispanic black children 

aged 1–5 years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination 

Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 4.19 (4.10 – 4.29) 2.47 (2.31 – 2.57) 3.97 (3.91 – 4.04) 8.02 (7.31 – 9.69) 1,634

1–5 years 4.55 (4.43 – 4.67) 3.11 (3.02 – 3.29) 4.37 (4.26 – 4.56) 6.68 (6.31 – 7.16) 401

Males

1–5 years 4.70 (4.56 – 4.86) 3.24† (3.06 – 3.37) 4.58 (4.30 – 4.89) 6.76† (6.42 – 7.77) 199

Females

Total, 1–5, 12–49 years 4.15 (4.05 – 4.26) 2.43 (2.27 – 2.55) 3.94 (3.86 – 4.00) 8.49 (7.37 – 9.87) 1,435

1–5 years 4.40 (4.21 – 4.59) 3.05† (2.73 – 3.23) 4.26 (4.00 – 4.47) 6.49† (5.96 – 7.16) 202

12–19 years 3.88 (3.77 – 4.00) 2.42 (2.25 – 2.52) 3.76 (3.66 – 3.87) 6.46 (6.14 – 7.07) 668

20–39 years 4.23 (4.08 – 4.39) 2.41 (2.06 – 2.58) 3.97 (3.85 – 4.15) 9.70 (7.33 – 10.5) 368

40–49 years 4.17 (3.89 – 4.47) 2.34† (1.94 – 2.61) 3.87 (3.51 – 4.08) 9.72† (8.28 – 13.2) 197

† Estimate is subject to greater uncertainty due to small cell size. 

Table 3.2.a.5. Serum soluble transferrin receptor: Non-Hispanic whites

Geometric mean and selected percentiles of serum concentrations (in mg/L) for non-Hispanic white children 

aged 1–5 years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination 

Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 3.43 (3.35 – 3.52) 2.02 (1.94 – 2.17) 3.32 (3.22 – 3.44) 5.59 (5.28 – 6.07) 2,048

1–5 years 4.22 (4.11 – 4.32) 2.91 (2.78 – 3.04) 4.15 (4.01 – 4.28) 5.90 (5.63 – 6.19) 391

Males

1–5 years 4.31 (4.16 – 4.46) 2.98† (2.91 – 3.15) 4.22 (3.99 – 4.48) 5.95† (5.67 – 6.83) 215

Females

Total, 1–5, 12–49 years 3.38 (3.30 – 3.47) 2.00 (1.97 – 2.05) 3.25 (3.14 – 3.37) 5.53 (5.18 – 6.08) 1,833

1–5 years 4.11 (3.96 – 4.27) 2.85† (2.64 – 2.97) 4.05 (3.88 – 4.27) 5.64† (5.36 – 6.64) 176

12–19 years 3.40 (3.33 – 3.46) 2.25 (2.12 – 2.35) 3.29 (3.20 – 3.37) 4.98 (4.78 – 5.49) 514

20–39 years 3.27 (3.18 – 3.36) 1.97 (1.94 – 2.01) 3.10 (3.00 – 3.20) 5.44 (4.96 – 6.01) 806

40–49 years 3.42 (3.26 – 3.59) 1.96 (1.92 – 2.01) 3.31 (3.03 – 3.57) 6.02 (5.41 – 6.76) 337

† Estimate is subject to greater uncertainty due to small cell size. 
326 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.2.b. Serum soluble transferrin receptor: Concentrations by survey cycle

Geometric mean and selected percentiles of serum concentrations (in mg/L) for children aged 1–5 and women 

aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total (Children 1–5 years, women 12–49 years) 

 2003–2004 3.63 (3.54 – 3.71) 2.06 (1.94 – 2.36) 3.55 (3.43 – 3.66) 5.96 (5.75 – 6.41) 2,831

 2005–2006 3.51 (3.42 – 3.60) 2.13 (2.00 – 2.20) 3.36 (3.28 – 3.47) 6.16 (5.77 – 6.63) 3,025

Age group

1–5 years (Children)

 2003–2004 4.44 (4.34 – 4.55) 3.28 (3.13 – 3.38) 4.33 (4.21 – 4.45) 5.99 (5.83 – 6.83) 696

 2005–2006 4.16 (4.04 – 4.27) 2.86 (2.79 – 2.93) 4.06 (3.89 – 4.21) 6.08 (5.79 – 6.48) 679

12–19 years (Women)

 2003–2004 3.57 (3.48 – 3.66) 2.29 (2.15 – 2.46) 3.49 (3.32 – 3.62) 5.72 (5.26 – 6.39) 975

 2005–2006 3.43 (3.36 – 3.49) 2.26 (2.13 – 2.35) 3.33 (3.25 – 3.38) 5.23 (5.01 – 5.81) 993

20–39 years (Women)

 2003–2004 3.49 (3.43 – 3.56) 2.02 (1.93 – 2.27) 3.33 (3.23 – 3.41) 5.96 (5.73 – 6.32) 803

 2005–2006 3.35 (3.24 – 3.47) 2.02 (1.90 – 2.13) 3.16 (3.04 – 3.31) 6.07 (5.54 – 6.57) 958

40–49 years (Women)

 2003–2004 3.49 (3.28 – 3.71) 1.96 (1.94 – 1.99) 3.33 (2.98 – 3.63) 6.01 (5.39 – 7.56) 357

 2005–2006 3.54 (3.36 – 3.74) 2.05 (1.66 – 2.23) 3.37 (3.19 – 3.65) 6.86 (6.22 – 7.89) 395

Gender

Males (1–5 years)

 2003–2004 4.54 (4.39 – 4.70) 3.32 (3.20 – 3.41) 4.40 (4.23 – 4.56) 6.38 (5.94 – 7.23) 358

 2005–2006 4.21 (4.05 – 4.38) 2.94 (2.74 – 3.02) 4.16 (3.90 – 4.34) 6.04 (5.69 – 6.52) 340

Females (1–5, 12–49 years)

 2003–2004 3.56 (3.47 – 3.65) 2.03 (1.93 – 2.32) 3.45 (3.31 – 3.59) 5.94 (5.64 – 6.37) 2,473

 2005–2006 3.46 (3.37 – 3.55) 2.11 (1.96 – 2.19) 3.31 (3.22 – 3.39) 6.17 (5.77 – 6.69) 2,685

Race/ethnicity (Children 1–5 years, women 12–49 years)

Mexican Americans

 2003–2004 3.63 (3.53 – 3.73) 2.18 (1.99 – 2.37) 3.59 (3.44 – 3.80) 5.88 (5.49 – 6.42) 734

 2005–2006 3.62 (3.46 – 3.79) 2.15 (2.02 – 2.24) 3.46 (3.28 – 3.62) 7.32 (6.16 – 8.70) 909

Non-Hispanic Blacks

 2003–2004 4.18 (4.04 – 4.33) 2.54 (2.33 – 2.65) 3.96 (3.89 – 4.06) 7.97 (6.94 – 9.88) 832

 2005–2006 4.20 (4.08 – 4.33) 2.36 (2.19 – 2.56) 4.00 (3.86 – 4.13) 8.17 (7.15 – 10.4) 802

Non-Hispanic Whites

 2003–2004 3.51 (3.37 – 3.65) 1.99 (1.98 – 2.03) 3.44 (3.22 – 3.63) 5.68 (5.16 – 6.38) 1,026

 2005–2006 3.36 (3.27 – 3.45) 2.09 (1.91 – 2.19) 3.24 (3.15 – 3.33) 5.55 (5.11 – 6.40) 1,022
12 

5th Percentile 50th Percentile 95th Percentile

10 

8 

6 

4 

5.0 

4.5 

4.0 

3.5 

3.0 

3.5 

3.0 

2.5 

2.0 

1.5 

1 1 1 1 

1 

1 

1 

1 1 

1 1 1 1 

1 

1 1 

1 1 

1 

1 

1 

1 

1 

1 1 

1 

1 

1 

1 

1 

1 

1 

1 1 

1 

1 

1 1 

1 

1 

1 1 

1 1 

1 

1 

1 

1 1 1 

1 

1 

1 

1 

03−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−06 

Total 1−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(M/F 1−5y, (F) (F) (1−5y) (1−5, (M/F 1−5y, (M/F 1−5y, (M/F 1−5y, 

F 12−49y) 12−49y) F 12−49y) F 12−49y) F 12−49y) 

Figure 3.2.b. Serum soluble transferrin receptor: Concentrations by survey cycle 

Selected percentiles in mg/L (95% confidence intervals), National Health and 


Nutrition Examination Survey, 2003–2006


3. Trace Elements 327
328 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.2.c. Serum soluble transferrin receptor: Prevalence

Prevalence (in percent) of high serum soluble transferrin receptor concentration (> 4.4 mg/L) for 

women in the U.S. population aged 12–49 years, National Health and Nutrition Examination Survey, 

2003–2006. 

Sample 

size

Prevalence 

(95% conf. interval)

Estimated total 

number of persons

Women, 12–49 years 4,481 18.9 (17.0 – 20.9) 14,918,000

Age group

12–19 years 1,968 16.9 (14.7 – 19.3) 2,741,000

20–49 years 2,513 19.4 (17.3 – 21.6) 12,159,000

Race/ethnicity

Mexican Americans 1,221 19.0 (15.5 – 23.0) 1,451,000

Non-Hispanic Blacks 1,233 34.9 (31.6 – 38.4) 3,756,000

Non-Hispanic Whites 1,657 16.0 (13.6 – 18.7) 8,177,000
3. Trace Elements 329

Table 3.2.d. Serum soluble transferrin receptor: Prevalence by survey cycle

Prevalence (in percent) of high serum soluble transferrin receptor concentration (> 4.4 mg/L) for women in the 

U.S. population aged 12–49 years, National Health and Nutrition Examination Survey, 2003–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Women, 12–49 years

 2003–2004 2,135 18.8 (16.3 – 21.6) 14,862,000

 2005–2006 2,346 18.9 (16.0 – 22.3) 15,017,000

Age group

12–19 years

 2003–2004 975 17.4 (14.0 – 21.3) 2,818,000

 2005–2006 993 16.4 (13.5 – 19.8) 2,694,000

20–49 years

 2003–2004 1,160 19.2 (16.3 – 22.4) 12,031,000

 2005–2006 1,353 19.6 (16.4 – 23.2) 12,296,000

Race/ethnicity

Mexican Americans

 2003–2004 547 18.7 (13.3 – 25.7) 1,435,000

 2005–2006 674 19.2 (14.6 – 24.7) 1,516,000

Non-Hispanic Blacks

 2003–2004 604 33.2 (28.9 – 37.7) 3,568,000

 2005–2006 629 36.7 (31.6 – 42.1) 3,988,000

Non-Hispanic Whites

 2003–2004 823 16.1 (12.5 – 20.5) 8,258,000

 2005–2006 834 15.8 (12.6 – 19.6) 7,991,000
330

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.3.a.1. Body iron

Arithmetic mean and selected percentiles of body iron (in mg/kg) for children aged 1–5 years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 2003–2006. 

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total 5.16 (5.01 – 5.31) -3.75 (-4.05 – -3.41) -1.83 (-2.60 – -1.41) 5.43 (5.32 – 5.58) 10.8 (10.6 – 11.2) 12.0 (11.5 – 12.5) 5,845

(Children 1–5 years, women 12–49 years)

Age group1–5 years (Children) 3.47 (3.31 – 3.63) -2.00 (-3.06 – -1.34) -.648 (-1.26 – -.159) 3.64 (3.44 – 3.79) 6.89 (6.72 – 7.06) 7.36 (7.17 – 7.87) 1,369

12–19 years (Women) 4.49 (4.26 – 4.72) -3.37 (-4.28 – -2.61) -1.59 (-2.69 – -.763) 4.96 (4.71 – 5.16) 8.84 (8.35 – 9.34) 9.61 (9.23 – 10.2) 1,967

20–39 years (Women) 5.51 (5.29 – 5.73) -3.76 (-4.09 – -3.12) -1.75 (-2.81 – -1.22) 5.88 (5.69 – 6.17) 10.7 (10.2 – 11.1) 11.6 (11.0 – 12.4) 1,758

40–49 years (Women) 5.88 (5.46 – 6.30) -4.43 (-5.33 – -3.76) -2.85 (-3.78 – -1.84) 6.37 (5.86 – 6.82) 12.4 (11.7 – 12.9) 13.1 (12.7 – 14.2) 751

GenderMales (1–5 years) 3.38 (3.17 – 3.59) -1.69 (-3.30 – -1.25) -.715 (-1.36 – -.262) 3.52 (3.32 – 3.80) 6.91 (6.65 – 7.30) 7.33 (6.93 – 8.12) 695

Females (1–5, 12–49 years) 5.30 (5.13 – 5.46) -3.78 (-4.06 – -3.50) -2.01 (-2.70 – -1.43) 5.65 (5.49 – 5.76) 11.0 (10.7 – 11.4) 12.1 (11.6 – 12.6) 5,150

Race/ethnicity(Children 1–5 years, women 12–49 years)Mexican Americans 4.49 (4.10 – 4.88) -4.49 (-5.27 – -3.69) -3.16 (-3.81 – -2.03) 4.75 (4.44 – 5.12) 10.4 (9.73 – 11.2) 11.4 (10.8 – 12.9) 1,641

Non-Hispanic Blacks 4.37 (4.10 – 4.64) -5.79 (-6.99 – -4.66) -3.79 (-4.61 – -2.88) 4.66 (4.30 – 5.05) 11.0 (10.3 – 11.6) 12.1 (11.3 – 13.2) 1,633

Non-Hispanic Whites 5.46 (5.24 – 5.69) -3.17 (-3.99 – -2.25) -1.21 (-2.34 – -.516) 5.66 (5.49 – 5.81) 10.9 (10.5 – 11.5) 12.0 (11.5 – 12.7) 2,041
1−5 12−19 20−39 40−49 

0 2 4 6 8

 Body iron (mg/kg) 

Overall 

1−5 12−19 20−39 40−49 

Mexican Americans 

Females 

Males 

8 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 3.3.a. Body iron: by age group 

Arithmetic mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Body iron Body iron (mg/kg) (mg/kg) 0 2 4 6 8 0 2 4 6 

1−5 12−19 20−39 40−49 1−5 12−19 20−39 40−49 

Females Males 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

1−5 12−19 20−39 40−49 

Age (years) Age (years) 

1−5 12−19 20−39 40−49 

3. Trace Elements 331
332 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.3.a.2. Body iron: Total population

Arithmetic mean and selected percentiles of body iron (in mg/kg) for children aged 1–5 years and women aged 

12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 2003–2006. 

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 5.16 (5.01 – 5.31) -1.83 (-2.60 – -1.41) 5.43 (5.32 – 5.58) 10.8 (10.6 – 11.2) 5,845

1–5 years 3.47 (3.31 – 3.63) -.648 (-1.26 – -.159) 3.64 (3.44 – 3.79) 6.89 (6.72 – 7.06) 1,369

Males

1–5 years 3.38 (3.17 – 3.59) -.715 (-1.36 – -.262) 3.52 (3.32 – 3.80) 6.91 (6.65 – 7.30) 695

Females

Total, Children 1–5 years, 

women 12–49 years 5.30 (5.13 – 5.46) -2.01 (-2.70 – -1.43) 5.65 (5.49 – 5.76) 11.0 (10.7 – 11.4) 5,150

1–5 years 3.57 (3.36 – 3.78) -.196 (-2.11 – .411) 3.70 (3.41 – 4.04) 6.89 (6.67 – 7.27) 674

12–19 years 4.49 (4.26 – 4.72) -1.59 (-2.69 – -.763) 4.96 (4.71 – 5.16) 8.84 (8.35 – 9.34) 1,967

20–39 years 5.51 (5.29 – 5.73) -1.75 (-2.81 – -1.22) 5.88 (5.69 – 6.17) 10.7 (10.2 – 11.1) 1,758

40–49 years 5.88 (5.46 – 6.30) -2.85 (-3.78 – -1.84) 6.37 (5.86 – 6.82) 12.4 (11.7 – 12.9) 751

Table 3.3.a.3. Body iron: Mexican Americans

Arithmetic mean and selected percentiles of body iron (in mg/kg) for Mexican American children aged 1–5 

years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 

2003–2006. 

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 4.49 (4.10 – 4.88) -3.16 (-3.81 – -2.03) 4.75 (4.44 – 5.12) 10.4 (9.73 – 11.2) 1,641

1–5 years 3.16 (2.84 – 3.48) -2.09 (-3.35 – -1.36) 3.48 (3.13 – 3.78) 6.99 (6.57 – 7.93) 422

Males

1–5 years 2.95 (2.48 – 3.41) -2.71† (-4.72 – -1.59) 3.34 (2.99 – 3.77) 6.92† (5.95 – 9.30) 203

Females

Total, Children 1–5 years, 

women 12–49 years 4.66 (4.23 – 5.10) -3.17 (-3.82 – -1.90) 5.02 (4.60 – 5.44) 10.6 (9.79 – 11.4) 1,438

1–5 years 3.38 (3.04 – 3.72) -1.88† (-2.87 – -.828) 3.55 (3.22 – 4.15) 6.99† (6.78 – 8.13) 219

12–19 years 4.07 (3.76 – 4.39) -1.76 (-3.29 – -.981) 4.46 (4.26 – 4.68) 8.99 (8.51 – 9.69) 637

20–39 years 5.07 (4.48 – 5.67) -3.15 (-4.31 – -1.66) 5.72 (4.93 – 6.28) 10.7 (9.89 – 12.0) 429

40–49 years 4.89 (3.74 – 6.04) -4.89† (-6.96 – -3.40) 5.33 (4.42 – 6.59) 11.1† (10.4 – 15.1) 153

† Estimate is subject to greater uncertainty due to small cell size. 
3. Trace Elements 333

Table 3.3.a.4. Body iron: Non-Hispanic blacks

Arithmetic mean and selected percentiles of body iron (in mg/kg) for non-Hispanic black children aged 1–5 

years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 

2003–2006. 

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 4.37 (4.10 – 4.64) -3.79 (-4.61 – -2.88) 4.66 (4.30 – 5.05) 11.0 (10.3 – 11.6) 1,633

1–5 years 3.83 (3.56 – 4.09) -.115 (-.906 – .776) 3.95 (3.78 – 4.25) 7.51 (6.80 – 8.03) 401

Males

1–5 years 3.63 (3.25 – 4.00) -.328† (-2.15 – .070) 3.77 (3.17 – 4.19) 6.90† (6.55 – 8.03) 199

Females

Total, Children 1–5 years, 

women 12–49 years 4.43 (4.14 – 4.72) -3.94 (-4.87 – -3.04) 4.80 (4.35 – 5.16) 11.0 (10.4 – 11.9) 1,434

1–5 years 4.03 (3.73 – 4.34) .658† (-.541 – .981) 4.17 (3.92 – 4.35) 7.71† (6.93 – 8.09) 202

12–19 years 3.99 (3.56 – 4.42) -2.53 (-3.91 – -1.71) 4.46 (4.09 – 4.79) 8.91 (8.38 – 9.43) 667

20–39 years 3.96 (3.63 – 4.28) -4.12 (-5.73 – -3.46) 4.35 (4.08 – 4.86) 9.96 (9.46 – 11.2) 368

40–49 years 5.78 (4.86 – 6.69) -5.62† (-9.51 – -2.80) 6.68 (5.78 – 7.32) 12.9† (11.9 – 15.4) 197

† Estimate is subject to greater uncertainty due to small cell size. 

Table 3.3.a.5. Body iron: Non-Hispanic whites

Arithmetic mean and selected percentiles of body iron (in mg/kg) for non-Hispanic white children aged 1–5 

years and women aged 12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 

2003–2006. 

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Males and Females

Total, Children 1–5 years, 

women 12–49 years 5.46 (5.24 – 5.69) -1.21 (-2.34 – -.516) 5.66 (5.49 – 5.81) 10.9 (10.5 – 11.5) 2,041

1–5 years 3.51 (3.27 – 3.74) -.264 (-1.28 – .300) 3.56 (3.34 – 3.92) 6.89 (6.64 – 7.00) 385

Males

1–5 years 3.42 (3.09 – 3.75) -.571† (-1.39 – .140) 3.50 (3.06 – 4.01) 6.91† (6.45 – 7.33) 212

Females

Total, Children 1–5 years, 

women 12–49 years 5.60 (5.36 – 5.84) -1.27 (-2.60 – -.546) 5.81 (5.66 – 6.02) 11.0 (10.7 – 11.5) 1,829

1–5 years 3.61 (3.33 – 3.89) .062† (-3.13 – .791) 3.67 (3.35 – 4.03) 6.70† (6.45 – 7.27) 173

12–19 years 4.68 (4.35 – 5.02) -1.48 (-3.15 – -.417) 5.17 (4.86 – 5.50) 8.84 (8.29 – 9.62) 514

20–39 years 5.93 (5.58 – 6.28) -.640 (-2.73 – .779) 6.16 (5.82 – 6.59) 10.7 (10.2 – 11.4) 805

40–49 years 6.01 (5.45 – 6.57) -2.26 (-3.78 – -1.01) 6.36 (5.77 – 6.99) 12.4 (11.6 – 13.0) 337

† Estimate is subject to greater uncertainty due to small cell size. 
334 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.3.b. Body iron: By survey cycle

Arithmetic mean and selected percentiles of body iron (in mg/kg) for children aged 1–5 years and women aged 

12–49 years in the U.S. population, National Health and Nutrition Examination Survey, 2003–2006. 

Arithmetic mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total (Children 1–5 years, women 12–49 years) 

 2003–2004 5.21 (5.03 – 5.39) -1.60 (-2.96 – -.854) 5.43 (5.32 – 5.55) 10.9 (10.7 – 11.3) 2,826

 2005–2006 5.11 (4.85 – 5.38) -2.04 (-2.73 – -1.43) 5.43 (5.08 – 5.71) 10.8 (10.2 – 11.5) 3,019

Age group

1–5 years (Children)

 2003–2004 3.25 (3.01 – 3.50) -.651 (-1.73 – .144) 3.34 (2.99 – 3.66) 6.55 (6.39 – 6.73) 694

 2005–2006 3.70 (3.47 – 3.94) -.642 (-1.65 – -.080) 3.91 (3.70 – 4.14) 7.00 (6.92 – 7.33) 675

12–19 years (Women)

 2003–2004 4.27 (3.89 – 4.66) -2.23 (-3.93 – -.653) 4.71 (4.27 – 5.11) 8.89 (8.29 – 9.73) 974

 2005–2006 4.71 (4.45 – 4.96) -1.45 (-2.64 – -.527) 5.10 (4.85 – 5.33) 8.53 (8.31 – 9.55) 993

20–39 years (Women)

 2003–2004 5.61 (5.33 – 5.89) -1.21 (-2.14 – -.835) 6.07 (5.69 – 6.25) 10.4 (9.92 – 11.1) 801

 2005–2006 5.42 (5.04 – 5.79) -2.55 (-3.91 – -1.41) 5.83 (5.44 – 6.27) 10.8 (10.2 – 11.9) 957

40–49 years (Women)

 2003–2004 6.22 (5.61 – 6.82) -3.28 (-3.80 – -1.85) 6.85 (6.21 – 7.33) 12.7 (12.0 – 13.4) 357

 2005–2006 5.55 (4.89 – 6.21) -2.47 (-4.61 – -1.59) 5.96 (5.33 – 6.66) 11.8 (11.1 – 13.1) 394

Gender

Males (1–5 years)

 2003–2004 3.11 (2.76 – 3.46) -.719 (-1.89 – -.152) 3.13 (2.70 – 3.65) 6.21 (5.74 – 6.92) 358

 2005–2006 3.68 (3.41 – 3.95) -.746 (-1.32 – -.268) 3.91 (3.48 – 4.41) 7.24 (6.81 – 8.27) 337

Females (1–5, 12–49 years)

 2003–2004 5.38 (5.18 – 5.58) -1.76 (-3.18 – -.854) 5.66 (5.50 – 5.80) 11.0 (10.7 – 11.5) 2,468

 2005–2006 5.22 (4.94 – 5.49) -2.20 (-2.98 – -1.52) 5.60 (5.32 – 5.84) 10.9 (10.2 – 11.6) 2,682

Race/ethnicity (Children 1–5 years, women 12–49 years)

Mexican Americans

 2003–2004 4.74 (4.13 – 5.35) -2.05 (-3.57 – -1.13) 4.94 (4.28 – 5.64) 10.6 (9.69 – 12.5) 734

 2005–2006 4.26 (3.78 – 4.73) -3.70 (-5.21 – -2.73) 4.71 (4.31 – 5.05) 9.91 (9.73 – 10.8) 907

Non-Hispanic Blacks

 2003–2004 4.48 (4.02 – 4.94) -3.79 (-5.06 – -2.47) 4.68 (4.15 – 5.24) 11.1 (9.95 – 12.7) 831

 2005–2006 4.26 (3.94 – 4.58) -3.96 (-4.99 – -2.62) 4.66 (4.16 – 5.17) 10.6 (9.86 – 11.4) 802

Non-Hispanic Whites

 2003–2004 5.45 (5.14 – 5.75) -.903 (-3.69 – .285) 5.57 (5.43 – 5.76) 11.0 (10.5 – 11.6) 1,023

 2005–2006 5.48 (5.12 – 5.85) -1.39 (-2.45 – -.593) 5.70 (5.42 – 6.01) 10.9 (10.2 – 12.0) 1,018
14 

5th Percentile 50th Percentile 95th Percentile

12 

10 

8 

6 

4 

7 

6 

5 

4 

3 

2 

2 

0 

−2 

−4 

−6 

j j 

j 

j 

j j 

j j 

j 

j 

j j j

j 

j 

j 

j j

j j 

j 

j 

j 

j 

j 

j 

j 

j 

j j 

j 

j j j 

j j 

j 

j 

j j 

j 

j 

j 

j 

j j 

j 

j j 

j j j 

j 

j 

03−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−0603−0405−06 

Total 1−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(M/F 1−5y, (F) (F) (1−5y) (1−5, (M/F 1−5y, (M/F 1−5y, (M/F 1−5y, 

F 12−49y) 12−49y) F 12−49y) F 12−49y) F 12−49y) 

 

 Figure 3.3.b. Body iron: By Survey Cycle 

Selected percentiles in mg/kg (95% confidence intervals), National Health and 

Nutrition Examination Survey, 2003–2006 

3. Trace Elements 335
336 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.3.c.1. Body iron: Prevalence

Prevalence (in percent) of low body iron (< 0 mg/kg) for children in the U.S. population aged 1–5 years, 

National Health and Nutrition Examination Survey, 2003–2006. 

Sample 

size

Prevalence

(95% conf. interval)

Estimated total 

number of persons

Children, 1–5 years 1,369 6.7 (5.0 – 8.8) 1,350,000

Gender

Males 695 7.8 (5.6 – 10.8) 807,000

Females 674 5.4 (3.4 – 8.3) 534,000

Race/ethnicity

Mexican Americans 422 10.9 (8.1 – 14.6) 333,000

Non-Hispanic Blacks 401 5.1 (3.0 – 8.6) 154,000

Non-Hispanic Whites 385 5.8 (3.6 – 9.1) 670,000
3. Trace Elements 337

Table 3.3.c.2. Body iron: Prevalence

Prevalence (in percent) of low body iron (< 0 mg/kg) for women in the U.S. population aged 12–49 

years, National Health and Nutrition Examination Survey, 2003–2006. 

Sample 

size

Prevalence 

(95% conf. interval)

Estimated total 

number of persons

Women, 12–49 years 4,476 9.5 (8.6 – 10.5) 7,515,000

Age group

12–19 years 1,967 9.3 (7.4 – 11.6) 1,508,000

20–49 years 2,509 9.6 (8.6 – 10.7) 6,006,000

Race/ethnicity

Mexican Americans 1,219 13.2 (10.2 – 16.9) 1,007,000

Non-Hispanic Blacks 1,232 16.2 (13.9 – 18.7) 1,739,000

Non-Hispanic Whites 1,656 7.4 (5.8 – 9.4) 3,803,000
338 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.3.d.1. Body iron: Prevalence by survey cycle

Prevalence (in percent) of low body iron (< 0 mg/kg) for children in the U.S. population aged 1–5 years, 

National Health and Nutrition Examination Survey, 2003–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Children, 1–5 years

 2003–2004 694 6.5 (4.3 – 9.8) 1,321,000

 2005–2006 675 6.8 (4.5 – 10.2) 1,377,000

Gender

Males

 2003–2004 358 8.3 (4.9 – 13.7) 854,000

 2005–2006 337 7.3 (4.7 – 11.1) 755,000

Females

 2003–2004 336 4.5 (2.7 – 7.4) 449,000

 2005–2006 338 6.3‡ (3.1 – 12.4) 620,000‡

Race/ethnicity

Mexican Americans

 2003–2004 187 13.3 (8.4 – 20.5) 405,000

 2005–2006 235 8.6 (6.0 – 12.1) 275,000

Non-Hispanic Blacks

 2003–2004 228 6.1‡ (3.1 – 11.8) 183,000‡

 2005–2006 173 § §

Non-Hispanic Whites

 2003–2004 201 4.6‡ (2.1 – 10.0) 538,000‡

 2005–2006 184 7.0 (3.8 – 12.5) 792,000

‡ Estimate flagged: 30% ≤ RSE < 40% for the prevalence estimate. 

§ Estimate suppressed: RSE ≥ 40% for the prevalence estimate. 
3. Trace Elements 339

Table 3.3.d.2. Body iron: Prevalence by survey cycle

Prevalence (in percent) of low body iron (< 0 mg/kg) for women in the U.S. population aged 12–49 years, 

National Health and Nutrition Examination Survey, 2003–2006. 

Sample size Prevalence (95% conf. interval) Estimated total number of persons

Women, 12–49 years

 2003–2004 2,132 8.6 (7.0 – 10.4) 6,773,000

 2005–2006 2,344 10.4 (9.3 – 11.7) 8,266,000

Age group

12–19 years

 2003–2004 974 9.0 (6.3 – 12.6) 1,455,000

 2005–2006 993 9.6 (6.9 – 13.2) 1,576,000

20–49 years

 2003–2004 1,158 8.5 (6.8 – 10.5) 5,322,000

 2005–2006 1,351 10.6 (9.5 – 11.9) 6,681,000

Race/ethnicity

Mexican Americans

 2003–2004 547 11.2 (7.6 – 16.2) 857,000

 2005–2006 672 15.1 (10.5 – 21.2) 1,193,000

Non-Hispanic Blacks

 2003–2004 603 16.0 (12.8 – 19.8) 1,720,000

 2005–2006 629 16.3 (13.1 – 20.1) 1,777,000

Non-Hispanic Whites

 2003–2004 822 6.9 (4.4 – 10.6) 3,530,000

 2005–2006 834 8.0 (6.0 – 10.5) 4,023,000
340 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

References

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Beard J. Indicators of the iron status of the population: free erythrocyte protoporphyrin and zinc protoporphyrin;

serum and plasma iron, total iron binding capacity and transferrin saturation; and serum transferrin receptor. In:

WHO/CDC. Assessing the iron status of populations: report of a joint World Health Organization/Centers for

Disease Control and Prevention technical consultation on the assessment of iron status at the population level.

Geneva: World Health Organization; 2007 [cited 2011]. Available at: http://www.who.int/nutrition/publications/

micronutrients/anaemia_iron_deficiency/9789241596107.pdf.

Cogswell ME, Looker AC, Pfeiffer CM, Cook JD, Lacher DA, Beard JL, et al. Assessment of iron deficiency in

US preschool children and nonpregnant females of childbearing age: National Health and Nutrition Examination

Survey 2003–2006. Am J Clin Nutr. 2009;89:1334–1342.

Cook JD, Flowers CH, Skikne BS. The quantitative assessment of body iron. Blood. 2003;101:3359–3364.

Flowers CH, Skikne BS, Covell AM, Cook JF. The clinical measurement of serum transferrin receptor. J Lab Clin

Med. 1989;114:368–377.

Grantham-McGregor S, Ani C. A review of studies on the effect of iron deficiency on cognitive development in

children. J Nutr. 2001;131(2S-2):649S–656S.

Haas JD, Brownlie T 4th. Iron deficiency and reduced work capacity: a critical review of the research to determine a

causal relationship. J Nutr. 2001;131:691S–696S.

Institute of Medicine, Food and Nutrition Board. Dietary reference intakes: vitamin A, vitamin K, arsenic, boron,

chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium and zinc. Washington, D.C.:

National Academy Press; 2001.

Kuiper-Kramer EPA, Coenen JLLM, Huisman CMS, Abbes A, van Raan J, van Eijk HG. Relation between soluble

transferrin receptors in serum and membrane-bound transferrin receptors. Acta Haematol. 1998;99:8–11.

Looker AC, Gunter EW, Johnson CL. Methods to assess iron status in various NHANES surveys. Nutr Rev.

1995;53:246–254.

Looker AC, Dallman PR, Carroll M, Gunter EW, Johnson CL. Prevalence of iron deficiency in the United States.

JAMA. 1997;277:973–975.

Looker AC, Cogswell ME, Gunter EW. Iron deficiency—United States, 1999–2000. Morb Mortal Wkly Rep.

2002;51:897–899.

Miret S, Simpson RJ, McKie AT. Physiology and molecular biology of dietary iron absorption. Annu Rev Nutr.

2003;23:283–301.

Pfeiffer CM, Cook JD, Mei Z, Cogswell ME, Looker AC, Lacher DA. Evaluation of an automated soluble

transferrin receptor (sTfR) assay on the Roche Hitachi analyzer and its comparison to two ELISA assays. Clin

Chim Acta 2007;382:112–116.

Pietrangelo A. Hereditary hemochromatosis—a new look at an old disease. N Engl J Med. 2004;350:2382–2397.

Pilch SM, Senti FR, editors. Assessment of iron nutritional status of the U.S. population based on data collected

in the Second National Health and Nutrition Examination Survey, 1976–1980. Bethesda (MD): Federation of

American Societies for Experimental Biology; 1984.

Schorr TO, Hediger ML. Anemia and iron-deficiency anemia: compilation of data on pregnancy outcome. Am J

Clin Nutr. 1994;59(Suppl):492S–501S.

Skikne BS, Flowers CH, Cook JD. Serum transferrin receptor: a quantitative measure of tissue iron deficiency.

Blood. 1990;75:1870–1876.

Thorpe SJ. The development and role of international biological reference materials in the diagnosis of anaemia.

Biologicals 2010;38:449–458.

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Americans, 2010. 7

thEdition, Washington, DC: U.S. Government Printing Office, December 2010 [cited 2011].

Available at: http://www.cnpp.usda.gov/DGAs2010-PolicyDocument.htm.
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World Health Organization (WHO)/UNICEF/UNU. Iron deficiency anaemia: assessment, prevention, and

control. A guide for programme managers. Geneva: World Health Organization; 2001 (WHO/NHD/01.3) [cited

2011]. Available at:

http://www.who.int/nutrition/publications/micronutrients/anaemia_iron_deficiency/WHO_NHD_01.3/en/index.

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deficiency/9789241596107.pdf.
342 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Iodine

Background Information

Sources and Physiological Functions. Iodine, a trace element found in soil, is an essential

component of the thyroid hormones involved in regulating the body’s metabolic processes

related to normal growth and development. Across the world, iodized salt and seafood are the

major dietary sources of iodine. In the United States, where the addition of iodine to salt is not

mandatory, most people get their iodine from dairy products and grains (bread) (Murray 2008).

In the United States, salt is iodized with potassium iodide at 100 parts per million (76 milligram

[mg] of iodine per kilogram [kg] of salt). Iodized salt is chosen by about 50–60% of the U.S.

population (Institute of Medicine 2001). Still, most ingested salt comes from processed food

(approximately 70%), which is typically not iodized in either the United States or in Canada (The

Public Health Committee of the American Thyroid Association 2006). Dairy products have been

identified as another important contributor to iodine status among reproductive-age women in

the United States (Perrine 2010).

Health Effects. Iodine deficiency disorders include mental retardation, hypothyroidism, goiter,

cretinism, and varying degrees of other growth and developmental abnormalities. Iodine deficiency

is the most preventable cause of mental retardation in the world (World Health Organization 2007).

Thyroid enlargement (goiter) is usually the earliest clinical feature of iodine deficiency. Thyroid

hormone is particularly important in the development of the central nervous system during the fetal

and early postnatal periods. In areas where iodized salt is common, iodine deficiency is rare. The

most critical period for iodine sufficiency is in utero through the first two years of life, when thyroid

hormones are required for normal brain development (World Health Organization 2007).

Excess iodine intake may also result in goiter, as well as in hyper- or hypothyroidism. High

iodine intake has also been associated with increased risk for thyroid papillary cancer (Institute of

Medicine 2001). For most people, iodine intake from usual foods and supplements is unlikely to

exceed the tolerable upper intake level (1100 μg/day) (Institute of Medicine 2001).

Intake Recommendations. The Institute of Medicine recommends the following daily intake of

iodine: 90 μg for children 1 to 8 years, 120 μg for children 9 to 13 years, 150 μg for adolescents

(14 to 18 years) and for nonpregnant adults, 220 μg per day for pregnant women, and 290 μg

per day during lactation (Institute of Medicine 2001). Dietary iodine requirements are higher in

pregnancy because of increased thyroid hormone production, increased renal iodine excretion,

and fetal iodine requirements (Glinoer 2007).

The World Health Organization (WHO)

recommends the following daily intake of iodine:

90 μg for preschool children (0 to 59 months);

120 μg for schoolchildren (6 to 12 years); 150 μg

for adolescents (above 12 years) and adults; and

250 μg for pregnant and lactating women (World

Health Organization 2007). The American

Thyroid Association recommends that North

American women receive dietary supplements

containing 150 μg iodine daily during pregnancy

and lactation and that all prenatal vitamins

contain 150 μg of iodine (Becker 2006). An

Endocrine Society Clinical Practice Guideline on

the management of thyroid dysfunction during
3. Trace Elements 343

pregnancy and postpartum recommends an average daily intake of 250 μg iodine for pregnant

women (Abalovich 2007). These recommendations have not yet been widely adopted. A current

survey of prenatal multivitamins marketed in the United States showed that 49% did not contain

iodine (Leung 2009). Furthermore, the majority of women of childbearing age (> 80%) are not

consuming supplements containing iodine (Gregory 2009).

Biochemical Indicators. Iodine deficiency develops when iodide intake is less than 20 μg/day

(Beers 2006). Most dietary iodine absorbed in the body eventually appears in the urine; thus,

urinary iodine excretion is recommended for assessing recent dietary iodine intake worldwide

(World Health Organization 2007).

WHO categories for median urinary iodine concentrations in school-age children and adults

(excluding pregnant and lactating women) are widely used to define iodine intake and nutrition

status for populations (World Health Organization 2007). An additional adequacy criterion

is that not more than 20% of samples from children and non-pregnant women be below 50

nanograms per milliliter (ng/mL) of iodine. These categories are useful for classifying population

risk, but they are not categories to define individual risk for adverse health outcomes. The large

day-to-day variations in urine iodine excretion, even among individuals with stable iodine intake,

tend to offset one another when the sample includes an adequately large number (100–500 spot

urine samples per group or subgroup) of representative individuals (Andersen 2008).

Epidemiological criteria for assessing iodine nutrition based on median urinary iodine 

concentrations of school-age children (> 6 years)* (World Health Organization 2007)

Median Urinary 

Iodine (ng/mL) Iodine Intake Iodine Status

< 20 Insufficient Severe iodine deficiency

20–49 Insufficient Moderate iodine deficiency

50–99 Insufficient Mild iodine deficiency

100–199 Adequate Adequate iodine nutrition

200–299 Above 

requirements

Likely to provide adequate intake for pregnant/lactating 

women but may pose a slight risk of more than adequate 

intake in the overall population

≥ 300 Excessive Risk for adverse health consequences (e.g., iodine-induced 

hyperthyroidism, autoimmune thyroid diseases)

* Applies to adults but not to pregnant and lactating women.

For pregnant women, median urinary iodine concentrations of 150–249 ng/mL represent

adequate iodine intake (World Health Organization 2007; Andersson 2007). Median urinary

iodine concentrations of < 150 ng/mL represent insufficient intake; 250–499 ng/mL represent

an intake above requirements, and ≥ 500 ng/mL represent an excessive intake. For lactating

women and children less than 2 years of age, median urinary iodine concentrations of 100 ng/

mL represent adequate iodine intake, but no other categories of iodine intake are defined (World

Health Organization 2007; Andersson 2007).

Data in NHANES. NHANES has measured urinary iodine since 1971. The NHANES III survey

(1988–1994) showed a sizable decrease in urinary iodine concentrations compared to concentrations

measured during NHANES I (1971–1974) (Hollowell 1998). This decline may have been due

to the dairy industry’s effort in the mid-1980s to reduce the iodine residue in milk from feed

supplements and iodophor sanitizing agents (Pennington 1996). Decreased concentrations of iodine

in fruit-flavored breakfast cereals resulted from a ban on erythrosine (an iodine-containing food
	

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BOEUIFVQQFSDPOëEFODFMJNJUPGUIFNFEJBOXBTKVTUTMJHIUMZXJUIJO

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Males Females 

Median urinary iodine (ng/mL)400 

300 

200 

100 

Adequate intake 

Above requirements 

Excessive intake 

6-11 12-19 20-39 40-59 60 

Insufficient intake 

0 

Age (years) 

Figure H.3.e. Median concentrations of urinary iodine in the U.S. population aged 6 years and older by age group and gender 

associated with estimated iodine intake, National Health and Nutrition Examination Survey, 2001–2006. 

Error bars represent 95% confidence intervals. 

344 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population 
3. Trace Elements 345

Urinary iodine concentrations have been relatively stable over almost two decades between 1988–

2006 (Figure H.3.f). They increased slightly (< 20%) between 1988–1994 and 2001–2002 in

the total population, in males, in females, and in non-Hispanic whites. However, they remained

unchanged in non-Hispanic blacks and Mexican Americans.

Figure H.3.f. Age-adjusted geometric mean concentrations of urinary iodine in the U.S. population aged 6 years and older by gender or 

race/ethnicity, National Health and Nutrition Examination Survey, 1988–2006. 

Error bars represent 95% confidence intervals. Within a demographic group, bars not sharing a common letter differ (p < 0.05).

Detailed Observations

The selected observations mentioned below are derived from the uncorrected tables and figures

presented next. The NHANES population is of sufficient size to allow group comparisons based

on uncorrected data. Statements about categorical differences between demographic groups noted

below are based on non-overlapping confidence limits from univariate analysis without adjusting

for demographic variables (i.e., age, sex, race/ethnicity) or other determinants of these urine

concentrations (i.e., dietary intake, supplement usage, smoking, BMI). A multivariate analysis may

alter the size and statistical significance of these categorical differences. Furthermore, additional

significant differences of smaller magnitude may be present despite their lack of mention here (e.g.,

if confidence limits slightly overlap or if differences are not statistically significant before covariate

adjustment has occurred). For a selection of citations of descriptive NHANES papers related to

these biochemical indicators of diet and nutrition, see Appendix G.

Geometric mean concentrations (NHANES 2003–2006):

•	 Urinary iodine concentrations followed a U-shaped age pattern, with the lowest

concentrations seen in young and middle-aged adults (Table 3.4.a.1 and Figure 3.4.a).

•	 Females had lower urinary iodine concentrations than males (Table 3.4.a.1 and Figure 3.4.a).

•	 Non-Hispanic blacks had lower urinary iodine concentrations than either non-Hispanic

whites or Mexican Americans (Table 3.4.a.1 and Figure 3.4.a).

Changes in geometric mean concentrations across survey cycles:

•	 We observed no change in urinary iodine concentrations between 2001 and 2006

(Table 3.4.b).

a 

a 

a 

a 

a a 

b 

b 

b 

a a b 

b 

c 

b 

a 

a 

b 

0 

50 

100 

150 

200 

Total 

population 

Males Females Mexican 

American 

NonHispanic 

black 

NonHispanic 

white 

Urinary iodine (ng/mL) 

1988-1994 2001-2002 2003-2006 
346

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.4.a.1. Urinary iodine: Concentrations

Geometric mean and selected percentiles of urine concentrations (in ng/mL) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total 156 (148 – 163) 23.3 (19.4 – 26.0) 33.0 (29.0 – 36.5) 162 (154 – 170) 603 (565 – 676) 816 (719 – 1,040) 5,175

(Children 1–5 years, women 12–49 years)

Age group6–11 years 222 (201 – 245) 36.4 (25.8 – 43.0) 51.6 (37.5 – 55.9) 232 (208 – 270) 764 (631 – 1,080) 1,040 (756 – 6,960) 666

12–19 years 179 (161 – 199) 24.9 (18.0 – 30.8) 36.7 (25.0 – 45.7) 186 (171 – 203) 741 (644 – 903) 936 (808 – 1,240) 1,443

20–39 years 135 (126 – 144) 20.0 (17.6 – 23.8) 29.4 (22.5 – 33.6) 140 (129 – 149) 515 (453 – 614) 679 (599 – 872) 1,134

40–59 years 137 (128 – 147) 20.0 (13.2 – 26.0) 28.4 (21.5 – 35.2) 145 (136 – 156) 489 (457 – 574) 674 (556 – 906) 91960 years and older 187 (170 – 205) 30.3 (25.9 – 37.7) 41.9 (36.9 – 49.0) 181 (168 – 202) 707 (616 – 1,080) 1,530 (1,050 – 4,320) 1,013

GenderMales 174 (164 – 185) 28.0 (22.4 – 32.9) 38.1 (34.9 – 42.5) 180 (172 – 189) 673 (581 – 760) 935 (743 – 1,260) 2,477

Females 140 (133 – 147) 20.0 (17.5 – 24.0) 28.5 (24.0 – 32.0) 144 (137 – 153) 571 (541 – 606) 762 (664 – 953) 2,698

Race/ethnicity(Children 1–5 years, women 12–49 years)Mexican Americans 173 (161 – 185) 30.7 (19.0 – 38.6) 40.2 (34.0 – 49.4) 186 (173 – 195) 591 (539 – 730) 768 (687 – 1,130) 1,320

Non-Hispanic Blacks 141 (131 – 151) 28.7 (25.7 – 30.8) 38.2 (31.1 – 44.0) 141 (128 – 152) 482 (442 – 554) 606 (535 – 770) 1,363

Non-Hispanic Whites 159 (151 – 168) 22.5 (18.9 – 25.8) 32.0 (27.9 – 36.6) 166 (156 – 176) 634 (570 – 714) 835 (731 – 1,170) 2,085
6−11 12−19 20−39 40−59 60+ 

0 100 200 300 400 

Urinary iodine (ng/mL) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

400 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 3.4.a. Urinary iodine: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary iodine Urinary iodine (ng/mL) (ng/mL) 0 100 200 300 400 0 100 200 300 

6−11 12−19 20−39 

Females 

40−59 60+ 6−11 12−19 20−39 

Males 

40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

6−11 12−19 

Age (years) 

20−39 40−59 60+ 6−11 12−19 

Age (years) 

20−39 40−59 60+ 

3. Trace Elements 347
348 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.4.a.2. Urinary iodine: Total population

Geometric mean and selected percentiles of urine concentrations (in ng/mL) for the total U.S. population aged 

6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 156 (148 – 163) 47.9 (42.9 – 53.9) 162 (154 – 170) 444 (422 – 467) 5,175

6–11 years 222 (201 – 245) 77.6 (55.8 – 94.7) 232 (208 – 270) 581 (515 – 754) 666

12–19 years 179 (161 – 199) 55.5 (44.3 – 68.0) 186 (171 – 203) 518 (465 – 658) 1,443

20–39 years 135 (126 – 144) 42.0 (33.9 – 52.9) 140 (129 – 149) 368 (323 – 416) 1,134

40–59 years 137 (128 – 147) 40.4 (36.9 – 45.7) 145 (136 – 156) 388 (359 – 423) 919

60 years and older 187 (170 – 205) 61.3 (52.0 – 68.5) 181 (168 – 202) 523 (463 – 580) 1,013

Males

Total, 6 years and older 174 (164 – 185) 56.4 (48.0 – 65.2) 180 (172 – 189) 465 (441 – 500) 2,477

6–11 years 250 (212 – 295) 94.3 (55.4 – 115) 264 (212 – 313) 653 (498 – 1,080) 307

12–19 years 200 (181 – 222) 73.1 (54.8 – 87.7) 198 (184 – 220) 525 (479 – 707) 693

20–39 years 154 (142 – 167) 53.6 (38.8 – 65.1) 160 (143 – 174) 408 (327 – 478) 512

40–59 years 149 (137 – 163) 48.3 (38.6 – 59.5) 148 (138 – 166) 395 (363 – 458) 454

60 years and older 211 (191 – 233) 65.1 (46.9 – 88.2) 205 (193 – 228) 538 (469 – 652) 511

Females

Total, 6 years and older 140 (133 – 147) 41.4 (37.7 – 46.8) 144 (137 – 153) 412 (389 – 453) 2,698

6–11 years 195 (176 – 215) 61.8 (45.8 – 81.5) 210 (174 – 232) 549 (423 – 718) 359

12–19 years 160 (137 – 186) 46.1 (29.2 – 59.0) 166 (143 – 191) 487 (421 – 633) 750

20–39 years 118 (107 – 131) 35.4 (30.4 – 43.8) 119 (108 – 136) 333 (300 – 406) 622

40–59 years 127 (116 – 139) 36.4 (28.2 – 40.1) 140 (123 – 161) 368 (333 – 418) 465

60 years and older 169 (151 – 189) 60.2 (48.9 – 67.7) 157 (134 – 176) 483 (413 – 590) 502

Table 3.4.a.3. Urinary iodine: Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in ng/mL) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 173 (161 – 185) 59.9 (52.3 – 68.3) 186 (173 – 195) 450 (404 – 518) 1,320

6–11 years 223 (196 – 253) 80.8 (54.8 – 98.9) 235 (208 – 265) 544 (469 – 713) 217

12–19 years 174 (155 – 194) 56.6 (44.9 – 62.7) 176 (163 – 203) 488 (414 – 596) 466

20–39 years 169 (153 – 186) 65.7 (55.6 – 78.5) 187 (165 – 198) 401 (352 – 547) 283

40–59 years 151 (124 – 184) 45.4 (33.9 – 59.5) 158 (123 – 196) 382 (305 – 699) 165

60 years and older 175 (148 – 207) 57.2 (43.7 – 69.2) 159 (128 – 193) 444 (377 – 690) 189

Males

Total, 6 years and older 173 (162 – 185) 61.8 (56.1 – 71.9) 184 (165 – 199) 454 (404 – 510) 623

6–11 years 224 (187 – 269) 85.2† (41.0 – 133) 236 (209 – 271) 519† (422 – 836) 96

12–19 years 194 (164 – 230) 60.8 (46.1 – 78.1) 199 (169 – 234) 549 (432 – 747) 221

20–39 years 167 (148 – 189) 62.3 (58.5 – 78.1) 184 (146 – 202) 386 (334 – 591) 134

40–59 years 139 (112 – 171) 45.1† (31.2 – 61.1) 122 (107 – 168) 369† (298 – 1,260) 77

60 years and older 196 (166 – 232) 70.5† (30.1 – 92.3) 196 (155 – 243) 495† (365 – 6,920) 95

Females

Total, 6 years and older 172 (159 – 187) 57.0 (45.9 – 67.4) 190 (164 – 205) 444 (373 – 566) 697

6–11 years 221 (182 – 269) 75.9 (47.0 – 94.8) 226 (180 – 270) 584 (456 – 1,110) 121

12–19 years 154 (134 – 178) 49.4 (34.7 – 61.1) 163 (142 – 188) 428 (338 – 695) 245

20–39 years 171 (148 – 198) 68.9 (39.1 – 81.4) 187 (145 – 219) 402 (348 – 569) 149

40–59 years 165 (128 – 212) 45.9† (20.2 – 64.8) 199 (145 – 218) 385† (295 – 1,150) 88

60 years and older 159 (117 – 218) 52.5† (34.2 – 61.4) 128 (107 – 163) 425† (283 – 1,010,900) 94

† Estimate is subject to greater uncertainty due to small cell size. 
3. Trace Elements 349

Table 3.4.a.4. Urinary iodine: Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in ng/mL) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 141 (131 – 151) 51.7 (47.6 – 57.0) 141 (128 – 152) 374 (322 – 423) 1,363

6–11 years 186 (163 – 213) 62.4 (45.7 – 76.1) 190 (168 – 217) 459 (387 – 682) 221

12–19 years 149 (137 – 163) 55.0 (47.9 – 61.0) 148 (138 – 168) 394 (351 – 475) 515

20–39 years 128 (113 – 145) 57.3 (47.2 – 66.3) 125 (116 – 160) 283 (242 – 310) 238

40–59 years 140 (124 – 160) 48.3 (35.7 – 59.1) 134 (122 – 144) 428 (337 – 485) 219

60 years and older 128 (108 – 151) 42.1 (35.0 – 50.6) 128 (102 – 146) 326 (259 – 529) 170

Males

Total, 6 years and older 158 (145 – 172) 58.1 (51.7 – 69.8) 159 (142 – 176) 408 (335 – 456) 663

6–11 years 208 (172 – 251) 75.9† (48.1 – 102) 205 (172 – 284) 500† (393 – 952) 106

12–19 years 161 (145 – 178) 61.4 (47.3 – 76.3) 155 (141 – 177) 409 (342 – 588) 260

20–39 years 141 (125 – 160) 61.0† (46.8 – 72.0) 154 (117 – 185) 292† (259 – 398) 108

40–59 years 161 (134 – 192) 55.5† (34.1 – 77.7) 145 (125 – 198) 429† (329 – 518) 104

60 years and older 145 (105 – 200) 42.6† (31.1 – 55.9) 141 (93.6 – 204) 414† (249 – 8,300) 85

Females

Total, 6 years and older 127 (117 – 138) 49.0 (41.9 – 53.8) 128 (121 – 136) 329 (307 – 380) 700

6–11 years 166 (145 – 190) 44.7 (39.2 – 67.1) 168 (151 – 211) 409 (381 – 581) 115

12–19 years 139 (124 – 156) 50.9 (36.2 – 59.2) 139 (125 – 164) 387 (312 – 475) 255

20–39 years 118 (98.4 – 142) 54.2 (27.1 – 66.6) 123 (105 – 148) 237 (212 – 342) 130

40–59 years 125 (107 – 147) 44.8 (30.9 – 53.4) 122 (103 – 137) 390 (290 – 516) 115

60 years and older 116 (91.7 – 148) 42.0† (12.9 – 50.6) 115 (83.6 – 146) 271† (244 – 466) 85

† Estimate is subject to greater uncertainty due to small cell size. 

Table 3.4.a.5. Urinary iodine: Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in ng/mL) for non-Hispanic whites in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 159 (151 – 168) 47.0 (41.1 – 54.3) 166 (156 – 176) 461 (427 – 489) 2,085

6–11 years 237 (208 – 271) 81.0 (55.0 – 103) 267 (202 – 315) 620 (536 – 978) 169

12–19 years 187 (160 – 218) 48.9 (36.7 – 73.4) 194 (172 – 224) 561 (481 – 744) 365

20–39 years 133 (122 – 145) 39.9 (32.0 – 49.0) 139 (125 – 150) 378 (318 – 461) 494

40–59 years 140 (131 – 151) 40.3 (35.6 – 48.7) 153 (139 – 167) 389 (361 – 424) 453

60 years and older 193 (175 – 214) 65.3 (55.5 – 74.1) 193 (172 – 211) 538 (460 – 598) 604

Males

Total, 6 years and older 182 (170 – 195) 58.0 (47.5 – 69.5) 187 (176 – 199) 481 (450 – 548) 996

6–11 years 292 (230 – 371) 112† (46.9 – 132) 315 (229 – 381) 741† (503 – 1,600) 76

12–19 years 213 (185 – 246) 77.2 (38.8 – 102) 208 (187 – 242) 564 (483 – 770) 174

20–39 years 159 (141 – 179) 51.0 (36.9 – 71.6) 163 (139 – 186) 413 (322 – 516) 211

40–59 years 153 (140 – 168) 49.7 (38.4 – 65.5) 153 (137 – 173) 396 (355 – 464) 229

60 years and older 220 (198 – 245) 66.6 (45.4 – 93.4) 218 (197 – 249) 548 (483 – 666) 306

Females

Total, 6 years and older 141 (132 – 149) 39.6 (33.9 – 44.0) 148 (137 – 157) 423 (390 – 471) 1,089

6–11 years 191 (166 – 221) 58.9† (38.5 – 81.6) 194 (150 – 251) 554† (423 – 855) 93

12–19 years 162 (127 – 206) 36.9 (18.6 – 58.0) 171 (138 – 227) 538 (431 – 793) 191

20–39 years 112 (98.2 – 129) 32.3 (22.5 – 41.6) 115 (102 – 130) 327 (278 – 461) 283

40–59 years 129 (117 – 143) 33.6 (24.7 – 40.7) 150 (123 – 178) 368 (334 – 425) 224

60 years and older 174 (153 – 197) 63.3 (50.0 – 72.8) 166 (137 – 191) 482 (401 – 613) 298

† Estimate is subject to greater uncertainty due to small cell size. 
350 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.4.b. Urinary iodine: Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in ng/mL) for the U.S. population, National 

Health and Nutrition Examination Survey, 2001–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2001–2002 162 (152 – 172) 30.1 (24.9 – 35.5) 168 (158 – 177) 713 (627 – 809) 2,837

 2003–2004 150 (141 – 160) 28.9 (24.9 – 33.7) 160 (146 – 172) 569 (493 – 660) 2,526

 2005–2006 161 (150 – 174) 36.0 (29.0 – 39.1) 164 (154 – 174) 665 (580 – 762) 2,649

Age group

6–11 years

 2001–2002 235 (208 – 266) 51.8 (25.5 – 65.9) 249 (220 – 288) 771 (700 – 918) 374

 2003–2004 209 (183 – 239) 45.7 (37.4 – 54.0) 229 (187 – 279) 613 (553 – 1,180) 315

 2005–2006 235 (201 – 276) 60.2 (28.0 – 80.9) 238 (197 – 279) 967 (673 – 2,950) 351

12–19 years

 2001–2002 192 (178 – 207) 38.3 (23.5 – 47.2) 205 (189 – 214) 803 (710 – 968) 831

 2003–2004 166 (141 – 195) 33.5 (17.9 – 46.4) 178 (144 – 203) 645 (503 – 924) 721

 2005–2006 193 (167 – 224) 38.2 (25.1 – 51.8) 194 (177 – 224) 797 (713 – 1,160) 722

20–39 years

 2001–2002 148 (132 – 166) 27.8 (22.0 – 40.6) 153 (136 – 173) 536 (473 – 762) 627

 2003–2004 138 (125 – 151) 23.8 (18.5 – 32.3) 146 (123 – 165) 564 (446 – 746) 517

 2005–2006 132 (120 – 145) 31.9 (22.3 – 40.0) 134 (124 – 143) 483 (412 – 601) 617

40–59 years

 2001–2002 140 (121 – 162) 24.5 (21.1 – 30.0) 141 (119 – 169) 689 (525 – 1,330) 496

 2003–2004 132 (119 – 147) 24.9 (13.1 – 35.0) 142 (128 – 161) 478 (422 – 690) 434

 2005–2006 143 (129 – 158) 34.6 (20.1 – 38.3) 148 (131 – 173) 519 (431 – 640) 485

60 years and older

 2001–2002 177 (156 – 200) 40.7 (30.1 – 48.7) 171 (152 – 198) 744 (617 – 1,250) 509

 2003–2004 169 (152 – 189) 39.7 (29.9 – 45.9) 170 (148 – 196) 635 (518 – 776) 539

 2005–2006 205 (175 – 240) 47.9 (35.6 – 59.7) 195 (172 – 223) 826 (620 – 4,220) 474

Gender

Males

 2001–2002 192 (178 – 208) 41.7 (35.0 – 48.0) 196 (179 – 209) 769 (630 – 981) 1,333

 2003–2004 169 (156 – 183) 38.8 (25.9 – 44.3) 178 (164 – 193) 584 (475 – 786) 1,229

 2005–2006 179 (163 – 197) 38.0 (32.9 – 44.8) 182 (172 – 195) 702 (595 – 960) 1,248

Females

 2001–2002 137 (127 – 148) 24.6 (21.3 – 29.2) 140 (126 – 156) 653 (576 – 736) 1,504

 2003–2004 134 (125 – 145) 25.0 (23.0 – 29.0) 141 (127 – 155) 559 (493 – 584) 1,297

 2005–2006 146 (136 – 158) 31.2 (20.6 – 39.0) 147 (137 – 155) 592 (544 – 693) 1,401

Race/ethnicity

Mexican Americans

 2001–2002 176 (163 – 189) 33.7 (29.0 – 42.3) 187 (168 – 206) 673 (527 – 883) 720

 2003–2004 168 (152 – 187) 38.7 (19.9 – 52.0) 186 (166 – 194) 568 (444 – 1,020) 617

 2005–2006 177 (161 – 195) 44.6 (34.7 – 54.0) 184 (165 – 210) 640 (531 – 1,030) 703

Non-Hispanic Blacks

 2001–2002 156 (137 – 178) 38.6 (30.6 – 45.7) 143 (124 – 172) 716 (608 – 918) 670

 2003–2004 134 (120 – 149) 42.3 (33.6 – 44.9) 131 (121 – 146) 456 (386 – 599) 634

 2005–2006 147 (133 – 163) 34.3 (27.8 – 42.0) 149 (137 – 164) 510 (440 – 678) 729

Non-Hispanic Whites

 2001–2002 163 (150 – 176) 29.2 (22.7 – 35.6) 169 (160 – 181) 734 (604 – 875) 1,222

 2003–2004 154 (144 – 164) 28.8 (23.9 – 33.8) 166 (151 – 181) 572 (486 – 684) 1,080

 2005–2006 165 (151 – 180) 35.3 (26.3 – 39.1) 166 (154 – 179) 678 (583 – 831) 1,005
5th Percentile 50th Percentile

j 

j j 

300 

j 

j 

j 

j 

j 

j 

j j j 

j 

j j 

j j j 

j j j 

j 

j 

j 

j j j 

j 

j j 

0 

1000 

2000 

3000 

95th Percentile

j 

j 

j 

j 

j 

j 

j 

j j 

j 

j 

j j j j j j j j 

j j 

j 

j j 

Figure 3.4.b. Urinary iodine: Concentrations by survey cycle 

Selected percentiles in ng/mL (95% confidence intervals), National Health and 

Nutrition Examination Survey, 2001–2006 

250 

200 

150 

100 

100 

80 

60 

40 

20 

0 

j j 

j 

j 

j 

j 

j

j 

j 

j j 

j 

j j j 

j j 

j j 

j 

j 

j j 

j 

j j 

j 

01−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

3. Trace Elements 351
352

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.5.a.1. Urinary iodine (creatinine corrected): Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 155 (147 – 163) 39.3 (37.1 – 41.7) 46.7 (44.7 – 50.0) 149 (140 – 156) 572 (525 – 628) 763 (663 – 932) 5,174Age group6–11 years 269 (244 – 297) 73.3 (56.4 – 81.6) 84.3 (77.6 – 92.2) 266 (240 – 293) 840 (653 – 1,190) 1,150 (827 – 7,820) 666

12–19 years 134 (124 – 145) 38.4 (35.1 – 42.1) 45.4 (41.0 – 49.7) 125 (115 – 137) 473 (406 – 555) 616 (528 – 835) 1,442

20–39 years 119 (111 – 127) 35.2 (32.5 – 38.8) 40.4 (37.5 – 44.9) 111 (103 – 119) 392 (347 – 485) 557 (450 – 903) 1,134

40–59 years 145 (136 – 156) 39.9 (34.1 – 42.0) 45.7 (41.2 – 50.6) 146 (132 – 158) 482 (421 – 526) 600 (519 – 738) 919

60 years and older 224 (209 – 241) 60.9 (53.6 – 65.5) 67.9 (65.6 – 71.0) 214 (191 – 237) 727 (660 – 891) 1,320 (863 – 5,710) 1,013

GenderMales 145 (137 – 153) 37.5 (35.0 – 39.6) 44.9 (41.2 – 47.7) 138 (129 – 149) 523 (479 – 591) 642 (584 – 1,140) 2,477

Females 165 (156 – 174) 42.1 (37.8 – 45.4) 49.7 (45.4 – 55.6) 157 (148 – 169) 617 (558 – 693) 807 (716 – 944) 2,697

Race/ethnicityMexican Americans 160 (151 – 170) 46.2 (42.1 – 49.9) 54.1 (50.2 – 58.7) 156 (146 – 163) 494 (470 – 617) 695 (588 – 1,060) 1,319

Non-Hispanic Blacks 98.6 (91.2 – 106) 29.1 (25.8 – 30.7) 33.1 (30.4 – 34.6) 90.4 (83.4 – 99.1) 360 (325 – 395) 493 (437 – 588) 1,363

Non-Hispanic Whites 167 (161 – 174) 45.0 (41.4 – 46.9) 53.2 (48.7 – 57.4) 158 (151 – 169) 602 (539 – 669) 819 (697 – 1,060) 2,085
6−11 12−19 20−39 40−59 60+ 

0 100 200 300 400 500 

Urinary iodine (μg/g creatinine) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

500 

Non−Hispanic Blacks Non−Hispanic Whites 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 

Figure 3.5.a. Urinary iodine (creatinine corrected): Concentrations by age group Urinary iodine Urinary iodine (μg/g creatinine) (μg/g creatinine) 0 100 200 300 400 500 0 100 200 300 400 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

3. Trace Elements 353
354 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.5.a.2. Urinary iodine (creatinine corrected): Total population

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 155 (147 – 163) 59.8 (56.4 – 64.0) 149 (140 – 156) 410 (391 – 438) 5,174

6–11 years 269 (244 – 297) 105 (92.1 – 115) 266 (240 – 293) 631 (590 – 820) 666

12–19 years 134 (124 – 145) 55.9 (49.7 – 61.9) 125 (115 – 137) 346 (301 – 386) 1,442

20–39 years 119 (111 – 127) 50.5 (46.7 – 55.0) 111 (103 – 119) 289 (271 – 324) 1,134

40–59 years 145 (136 – 156) 58.4 (50.9 – 63.7) 146 (132 – 158) 357 (322 – 408) 919

60 years and older 224 (209 – 241) 83.6 (75.9 – 92.3) 214 (191 – 237) 552 (481 – 635) 1,013

Males

Total, 6 years and older 145 (137 – 153) 56.5 (52.3 – 60.2) 138 (129 – 149) 382 (357 – 414) 2,477

6–11 years 283 (248 – 323) 108 (83.8 – 131) 280 (245 – 322) 631 (589 – 1,060) 307

12–19 years 134 (122 – 148) 52.4 (46.2 – 58.2) 132 (117 – 149) 347 (300 – 413) 693

20–39 years 114 (106 – 123) 50.3 (44.9 – 54.6) 103 (93.8 – 114) 276 (264 – 335) 512

40–59 years 129 (119 – 140) 52.1 (45.8 – 60.0) 126 (113 – 136) 311 (274 – 392) 454

60 years and older 198 (183 – 215) 73.1 (67.3 – 83.9) 180 (168 – 205) 440 (407 – 481) 511

Females

Total, 6 years and older 165 (156 – 174) 63.9 (57.9 – 69.6) 157 (148 – 169) 439 (403 – 481) 2,697

6–11 years 256 (228 – 286) 99.9 (87.8 – 114) 247 (227 – 293) 630 (529 – 821) 359

12–19 years 134 (121 – 148) 59.3 (51.3 – 64.9) 121 (111 – 131) 332 (292 – 403) 749

20–39 years 123 (112 – 136) 51.0 (45.8 – 57.9) 118 (107 – 130) 292 (254 – 359) 622

40–59 years 162 (148 – 178) 63.8 (55.7 – 70.9) 166 (145 – 188) 408 (344 – 482) 465

60 years and older 247 (224 – 272) 92.2 (79.1 – 104) 243 (221 – 262) 617 (554 – 696) 502

Table 3.5.a.3. Urinary iodine (creatinine corrected): Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for Mexican Americans in 

the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 160 (151 – 170) 67.5 (60.4 – 70.6) 156 (146 – 163) 383 (343 – 470) 1,319

6–11 years 276 (246 – 311) 123 (103 – 138) 267 (242 – 293) 619 (468 – 925) 217

12–19 years 146 (131 – 163) 61.9 (53.6 – 72.7) 143 (128 – 157) 344 (285 – 468) 465

20–39 years 137 (125 – 149) 59.7 (53.7 – 71.1) 137 (120 – 147) 293 (261 – 384) 283

40–59 years 146 (129 – 164) 66.0 (55.3 – 69.3) 148 (124 – 161) 317 (292 – 382) 165

60 years and older 222 (193 – 255) 85.2 (67.8 – 101) 210 (167 – 247) 459 (385 – 725) 189

Males

Total, 6 years and older 148 (137 – 159) 60.0 (56.3 – 65.7) 147 (131 – 163) 361 (319 – 428) 623

6–11 years 269 (236 – 307) 126† (81.6 – 166) 278 (226 – 318) 541† (454 – 725) 96

12–19 years 147 (125 – 173) 58.5 (46.3 – 72.5) 141 (121 – 168) 346 (282 – 519) 221

20–39 years 124 (111 – 139) 55.7 (46.1 – 64.8) 121 (109 – 146) 244 (220 – 435) 134

40–59 years 133 (111 – 160) 58.9† (40.2 – 67.6) 136 (101 – 161) 318† (285 – 383) 77

60 years and older 189 (167 – 213) 81.1† (67.3 – 99.9) 168 (144 – 204) 410† (319 – 1,020) 95

Females

Total, 6 years and older 174 (164 – 186) 73.4 (67.6 – 78.3) 162 (156 – 177) 416 (352 – 488) 696

6–11 years 284 (237 – 340) 116 (101 – 134) 250 (224 – 299) 656 (468 – 2,530) 121

12–19 years 145 (129 – 162) 67.1 (55.5 – 74.4) 144 (123 – 157) 333 (267 – 492) 244

20–39 years 153 (139 – 168) 73.4 (51.7 – 84.7) 143 (125 – 162) 344 (293 – 446) 149

40–59 years 160 (141 – 182) 68.0† (59.1 – 82.3) 160 (141 – 181) 308† (264 – 434) 88

60 years and older 253 (204 – 315) 86.1† (23.2 – 124) 232 (196 – 265) 502† (415 – 2,790) 94

† Estimate is subject to greater uncertainty due to small cell size. 
3. Trace Elements 355

Table 3.5.a.4. Urinary iodine (creatinine corrected): Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic blacks 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 98.6 (91.2 – 106) 39.0 (35.8 – 41.7) 90.4 (83.4 – 99.1) 264 (248 – 293) 1,363

6–11 years 188 (164 – 214) 80.2 (67.6 – 87.6) 180 (152 – 221) 448 (376 – 558) 221

12–19 years 90.8 (83.6 – 98.6) 40.5 (36.5 – 42.5) 87.0 (78.8 – 95.5) 223 (191 – 258) 515

20–39 years 75.5 (67.9 – 83.9) 35.6 (31.1 – 38.6) 72.6 (63.6 – 80.4) 209 (137 – 254) 238

40–59 years 98.3 (88.0 – 110) 38.1 (32.9 – 45.4) 90.5 (78.2 – 103) 257 (217 – 296) 219

60 years and older 123 (106 – 143) 46.0 (40.3 – 50.9) 108 (98.4 – 129) 337 (251 – 498) 170

Males

Total, 6 years and older 101 (90.7 – 112) 37.6 (33.7 – 41.2) 92.1 (80.8 – 103) 294 (254 – 360) 663

6–11 years 187 (152 – 231) 73.7† (52.4 – 87.7) 178 (142 – 244) 447† (360 – 898) 106

12–19 years 90.1 (81.4 – 99.7) 37.4 (31.5 – 41.8) 84.8 (75.5 – 97.0) 224 (196 – 264) 260

20–39 years 76.2 (67.5 – 85.9) 35.3† (27.7 – 38.4) 71.7 (62.5 – 78.5) 215† (127 – 285) 108

40–59 years 105 (87.6 – 126) 34.3† (29.7 – 47.5) 93.8 (73.4 – 130) 286† (239 – 559) 104

60 years and older 123 (89.2 – 170) 41.0† (34.7 – 49.6) 103 (78.5 – 159) 365† (242 – 4,440) 85

Females

Total, 6 years and older 96.5 (89.3 – 104) 39.3 (35.7 – 44.7) 89.3 (84.3 – 97.6) 247 (218 – 285) 700

6–11 years 188 (167 – 211) 83.8 (68.1 – 98.7) 185 (152 – 220) 442 (375 – 548) 115

12–19 years 91.5 (82.1 – 102) 42.8 (36.5 – 46.2) 88.5 (76.0 – 99.7) 205 (164 – 311) 255

20–39 years 74.9 (64.2 – 87.5) 36.1 (30.0 – 39.1) 72.7 (60.5 – 84.3) 196 (130 – 248) 130

40–59 years 92.9 (83.6 – 103) 39.5 (29.3 – 47.1) 88.5 (73.7 – 99.0) 217 (196 – 284) 115

60 years and older 123 (99.9 – 152) 50.2† (30.9 – 61.9) 111 (97.1 – 134) 255† (229 – 540) 85

† Estimate is subject to greater uncertainty due to small cell size. 

Table 3.5.a.5. Urinary iodine (creatinine corrected): Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic whites 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 167 (161 – 174) 67.2 (63.6 – 69.2) 158 (151 – 169) 430 (404 – 472) 2,085

6–11 years 299 (261 – 342) 114 (92.8 – 132) 289 (259 – 348) 663 (616 – 1,050) 169

12–19 years 147 (134 – 161) 63.3 (54.3 – 69.8) 135 (122 – 155) 374 (311 – 447) 365

20–39 years 125 (118 – 133) 55.5 (47.8 – 62.1) 115 (107 – 124) 298 (274 – 345) 494

40–59 years 155 (145 – 166) 62.7 (56.4 – 69.7) 155 (140 – 174) 364 (327 – 419) 453

60 years and older 236 (218 – 256) 94.3 (82.5 – 102) 233 (196 – 248) 559 (481 – 657) 604

Males

Total, 6 years and older 157 (149 – 165) 64.0 (61.1 – 67.2) 150 (140 – 156) 396 (368 – 428) 996

6–11 years 337 (272 – 417) 131† (63.9 – 170) 326 (268 – 429) 811† (610 – 2,040) 76

12–19 years 149 (135 – 163) 59.4 (49.6 – 67.3) 143 (129 – 170) 378 (301 – 455) 174

20–39 years 122 (111 – 135) 57.5 (46.5 – 65.4) 104 (93.8 – 122) 292 (265 – 349) 211

40–59 years 137 (126 – 149) 59.3 (48.9 – 64.1) 136 (120 – 152) 313 (274 – 414) 229

60 years and older 208 (192 – 226) 82.9 (70.7 – 95.2) 189 (173 – 215) 440 (402 – 522) 306

Females

Total, 6 years and older 178 (169 – 188) 70.6 (64.9 – 74.3) 169 (156 – 183) 464 (431 – 514) 1,089

6–11 years 265 (225 – 311) 99.1† (84.0 – 118) 262 (227 – 315) 640† (474 – 1,020) 93

12–19 years 145 (127 – 167) 65.0 (56.0 – 74.0) 127 (112 – 152) 368 (292 – 499) 191

20–39 years 128 (116 – 142) 51.3 (45.4 – 62.5) 123 (110 – 141) 295 (242 – 391) 283

40–59 years 175 (159 – 193) 70.6 (58.0 – 79.3) 179 (152 – 202) 433 (362 – 496) 224

60 years and older 261 (232 – 294) 104 (81.2 – 119) 255 (236 – 280) 630 (556 – 697) 298

† Estimate is subject to greater uncertainty due to small cell size. 
356 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 3.5.b. Urinary iodine (creatinine corrected): Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the U.S. population, 

National Health and Nutrition Examination Survey, 2001–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 2001–2002 163 (153 – 173) 50.0 (46.8 – 54.0) 151 (141 – 165) 620 (567 – 687) 2,835

 2003–2004 146 (135 – 158) 45.4 (39.4 – 49.3) 142 (130 – 154) 492 (449 – 585) 2,525

 2005–2006 163 (153 – 175) 50.0 (45.0 – 54.7) 155 (143 – 169) 620 (549 – 733) 2,649

Age group

6–11 years

 2001–2002 273 (246 – 304) 94.5 (75.7 – 106) 257 (220 – 319) 923 (772 – 1,140) 374

 2003–2004 254 (228 – 283) 84.4 (71.9 – 98.7) 246 (233 – 269) 718 (615 – 1,210) 315

 2005–2006 286 (242 – 339) 82.5 (64.3 – 98.9) 288 (236 – 362) 947 (654 – 2,300) 351

12–19 years

 2001–2002 149 (137 – 161) 52.5 (47.8 – 58.9) 138 (129 – 146) 601 (450 – 721) 830

 2003–2004 124 (109 – 141) 45.4 (36.3 – 49.9) 117 (104 – 132) 381 (314 – 532) 720

 2005–2006 145 (130 – 162) 45.4 (39.8 – 51.9) 138 (117 – 163) 477 (434 – 829) 722

20–39 years

 2001–2002 135 (127 – 143) 46.7 (42.2 – 49.5) 128 (118 – 136) 470 (443 – 577) 627

 2003–2004 115 (104 – 127) 39.2 (33.9 – 44.9) 108 (99.3 – 119) 407 (319 – 559) 517

 2005–2006 123 (112 – 135) 43.9 (39.1 – 49.0) 114 (97.7 – 131) 378 (339 – 592) 617

40–59 years

 2001–2002 151 (130 – 175) 44.7 (37.9 – 54.5) 142 (120 – 176) 522 (427 – 712) 496

 2003–2004 138 (126 – 152) 42.0 (34.9 – 49.9) 136 (126 – 150) 436 (392 – 561) 434

 2005–2006 152 (137 – 170) 47.0 (40.9 – 56.5) 153 (126 – 179) 492 (429 – 544) 485

60 years and older

 2001–2002 216 (192 – 244) 67.1 (51.2 – 75.5) 199 (179 – 230) 751 (632 – 1,000) 508

 2003–2004 204 (188 – 222) 67.2 (60.3 – 74.0) 197 (178 – 233) 595 (521 – 726) 539

 2005–2006 246 (218 – 277) 68.4 (65.8 – 72.8) 235 (193 – 256) 858 (697 – 5,190) 474

Gender

Males

 2001–2002 156 (143 – 171) 47.0 (43.7 – 51.1) 145 (137 – 160) 578 (514 – 674) 1,333

 2003–2004 137 (127 – 148) 41.7 (36.3 – 46.4) 132 (121 – 146) 481 (417 – 590) 1,229

 2005–2006 152 (140 – 165) 47.8 (42.6 – 50.4) 147 (132 – 158) 540 (480 – 795) 1,248

Females

 2001–2002 170 (161 – 179) 55.2 (48.0 – 57.1) 158 (146 – 168) 670 (585 – 748) 1,502

 2003–2004 155 (142 – 169) 46.9 (41.8 – 52.7) 151 (133 – 167) 532 (452 – 630) 1,296

 2005–2006 176 (163 – 189) 54.4 (44.6 – 60.3) 164 (150 – 179) 687 (598 – 829) 1,401

Race/ethnicity

Mexican Americans

 2001–2002 164 (152 – 176) 56.0 (49.4 – 61.0) 154 (140 – 177) 589 (469 – 754) 720

 2003–2004 152 (138 – 169) 51.3 (42.1 – 58.9) 147 (133 – 164) 481 (389 – 1,100) 616

 2005–2006 167 (154 – 181) 56.2 (51.7 – 60.0) 163 (153 – 179) 544 (454 – 728) 703

Non-Hispanic Blacks

 2001–2002 113 (103 – 124) 36.8 (27.9 – 42.8) 103 (93.5 – 115) 440 (361 – 645) 669

 2003–2004 92.1 (81.2 – 104) 33.1 (29.7 – 33.8) 84.6 (73.1 – 97.6) 336 (296 – 375) 634

 2005–2006 105 (96.7 – 115) 33.7 (29.8 – 37.7) 96.6 (87.0 – 111) 397 (315 – 513) 729

Non-Hispanic Whites

 2001–2002 175 (163 – 188) 55.1 (48.3 – 58.2) 164 (151 – 176) 652 (576 – 749) 1,221

 2003–2004 159 (150 – 168) 50.9 (46.3 – 58.2) 153 (147 – 161) 526 (442 – 621) 1,080

 2005–2006 177 (166 – 188) 55.0 (45.8 – 59.4) 168 (152 – 179) 656 (561 – 868) 1,005
2500 


2000 


5th Percentile 50th Percentile 95th Percentile 1500 

1000 

500 

0 

400 

300 

200 

100 

0 

120 

100 

80 

60 

40 

20 

1 

1 

1 

1 

1 

1 

1 

1 1 1 

1 

1 1 

1 1 

1 

1 

1 

1

1 1 

1 

1 1 

1 

1 

1 

1 1 1 

1 1 

1 

1 

1 

1 1 1 1 1 1 1 1 1 1 1 1 

1 

1 

1 1 

1 1 1 

1 

1 

1 

1

1 1 

1 

1 1 1 1 

1 1 

1 

1 

1 

1 

1 1 

1 

1 

1 1 1 

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1 

1 

01−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−0601−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Figure 3.5.b. Urinary iodine (creatinine corrected): Concentrations by survey cycle 

Selected percentiles in μg/g creatinine (95% confidence intervals), 


National Health and Nutrition Examination Survey, 2001–2006 


3. Trace Elements 357
358 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

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for number of samples in groups and in individuals. Br J Nutr. 2008;99:813–818.

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lactating women and in children less than 2-years-old: conclusions and recommendations of the Technical

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pregnancy and lactation—United States and Canada: recommendations of the American Thyroid Association.

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plasma mass spectrometry to measure urinary iodine in NHANES 2000: comparison with previous method. Clin

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Nutrition Examination Survey, 2005–2006 and 2007–2008. Thyroid. 2011;21:419–427.

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4. Isoflavones and Lignans 361

4. Isoflavones and Lignans 

Isoflavones

•	 Genistein

•	 Daidzein

•	 Equol

•	 O-Desmethylangolensin

Lignans

•	 Enterodiol

•	 Enterolactone
362 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Isoflavones and Lignans

Background Information

Sources and Physiological Functions. Isoflavones and lignans are secondary plant metabolites

frequently encountered in the diet. When ingested and metabolized, these compounds

have the potential to act as phytoestrogens, a class of compounds that have weak estrogenic

effects. This report considers urinary concentrations of four isoflavones (daidzein, genistein,

O-desmethylangolensin [ODMA], and equol) and two lignans (enterodiol and enterolactone).

Diet is the primary source of human exposure to phytoestrogens. Plant sources of isoflavones

include legumes, with the largest contribution coming from soy-based foods. Since soy flour and

soy protein isolates may be added to processed meats, meat substitutes, breads, and protein-food

bars, these items can be a major source of isoflavones (Lampe 1999; Grace 2004). However, the

isoflavone content of soy protein preparations can vary widely, and it is affected by production

techniques (Erdman 2004). Daidzein and genistein are the main soy isoflavones. Kudzu root,

used in some dietary supplements, also contains appreciable amounts of daidzein. Naringenin,

a precursor to genistein, is found in some citrus fruits. Formononetin and biochanin A are

methylated isoflavones found in clover, which may be used in red clover dietary supplements, and

they are metabolized in the body to daidzein and genistein, respectively. Lignans are found in flax

seeds, whole wheat flour, tea, some fruits, and other cereal grains. Lignans include matairesinol

and secoisolariciresinol, which are transformed by intestinal bacteria into the estrogenic

coumpounds enterolactone and enterodiol, respectively (Rowland 2003; Cornwell 2004).

Enterodiol may also convert into enterolactone and vice versa. Isoflavone intake is typically higher

in Asian populations than in Western populations, primarily due to the higher soy consumption

and the significant role that such fermented food products as tempeh, miso, or natto play in Asian

diets (Mortensen 2009). Lignan intake varies greatly from country to country because of different

dietary sources; however, completeness of food composition data is also a confounding factor in

interpreting these data (Peterson 2010).

The absorption and metabolism of phytoestrogens varies considerably among individuals. The

variation may relate to differences in absorption, enterohepatic circulation, and metabolism

by intestinal bacteria. Isoflavones and lignans occur primarily as glycosides in unfermented

foods with a small percentage of aglycones present. Aglycones represent a larger portion of

the phytoestrogens present in fermented foods due to bacterial hydrolysis of the glycosides.

Glycosidic forms are hydrolyzed to their aglycones in the intestine, absorbed, and then linked

in the intestinal wall and liver with glucuronic acid to make them more water-soluble, a process

known as glucuronidation. The glucuronidated metabolites of isoflavones predominate in blood

and urine (Doerge 2000; Rowland 2003; Clavel 2006; Nielsen 2007). Ingested daidzein is further

metabolized to ODMA and to equol by intestinal bacteria. Equol, but not ODMA, has estrogenic

activity. About 30 percent of adults produce equol and have higher serum equol concentrations

after they consume daidzein (Setchell 2003a; Cassidy 2006). This ability to produce equol may be

related to an individual’s intestinal microflora and influenced by dietary habits and genetic factors

(Rowland 2000; Setchell 2002; Setchell 2006). It is unclear whether the ability to produce equol

results in any health-related effects (Vafeiadou 2006).

Generally, phytoestrogens are much less potent than endogenously produced estrogens, but

phytoestrogens can be present in much greater quantities (100 to 1000 times the concentration of

endogenous estrogens). Additionally, phytoestrogens bind less tightly to steroid-hormone serum-
4. Isoflavones and Lignans 363

transport proteins than do endogenous estrogens

(Nagel 1998). Equol has more potent estrogen

activity than its precursor daidzein and has been

proposed to be most important in explaining the

possible mechanism of action of isoflavones in

disease prevention (Setchell 2002).

Health Effects. The dietary consumption of

phytoestrogens is believed to be associated with

a reduced risk of hormone-dependent cancers,

such as breast (Dong 2010; Buck 2010) and

prostate cancer (Yan 2009; Hamilton-Reeves

2010), due to antagonistic mechanisms related to

hormone receptor binding. Other health benefits

related to the consumption of phytoestrogenrich diets have also been proposed: reduced

severity of menopause-related symptoms (Howes 2006; Jacobs 2009); cardiovascular health (Pan

2009; Peterson 2010); and modulation of osteoporosis (Liu 2010). A report from the Agency for

Healthcare Research and Quality (Balk 2005) about the effects of soy on health outcomes reported

that there is no conclusive evidence of a dose-response effect of either soy protein or isoflavone

on cardiovascular diseases, menopausal symptoms, endocrine function, cancer, bone health,

reproductive health, kidney diseases, cognitive function, or glucose metabolism. For reducing lowdensity lipoprotein concentrations, however, soy protein could possibly have a dose-response effect.

As for lignan intake, flaxseed has been shown to significantly reduce LDL- and total cholesterol

depending on the type of intervention, sex, and lipid profiles of the subjects (Pan 2009).

Adverse effects on fertility have been observed in animals that graze on red clover. Results of

chronic feeding studies in pregnant animals suggest that high doses of phytoestrogens alter the

fetal hormonal environment (Cornwell 2004). Infants who consume soy-based formula can have

plasma concentrations of isoflavones that are 13,000–22,000 times higher than concentrations of

endogenous estrogen in infants (Setchell 1997). Yet, studies of children who had been fed soybased formula as infants and who were followed through adolescence (Klein 1998) and young

adulthood (Strom 2001) found no adverse reproductive or endocrine effects. A meta-analysis of

32 studies in which adult men consumed soy foods, isolated soy protein, or isoflavone extracts

(from soy or red clover) found that neither soy foods nor isoflavone supplements alter measures

of bioavailable testosterone concentrations in men (Hamilton-Reeves 2010). In vitro and animal

studies also suggest that soy isoflavones may have immunologic and thyroid effects (Doerge 2002).

The Center for the Evaluation of Risks to Human Reproduction (CERHR) of the National

Toxicology Program reviewed the developmental and reproductive toxicity of both soy formula

and genistein and concluded that available data were inadequate to determine the effects of soy

formula on developmental or reproductive toxicity (Rozman 2006a). The expert review panel

expressed negligible concern for adverse effects in the general population of consuming dietary

sources of genistein: under current exposure conditions, adults would be unlikely to consume

sufficient daily levels of genistein to cause adverse reproductive and/or developmental effects

(Rozman 2006b). A subsequent review by CERHR that included new study data from 2006–

2009 and focused specifically on the developmental toxicity of soy infant formula and its major

isoflavone components found minimal concern for adverse effects on development in infants who

consume soy infant formula (McCarver 2011).
364 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Biochemical Indicators and Methods. A systematic review of intervention studies has shown

that urinary concentrations of daidzein, genistein, and enterolactone are good biomarkers of

dietary intake (Pearson r = 0.78–0.87) as compared to equol, ODMA (0.38–0.40) and enterodiol

(-0.14) (Pérez-Jiménez 2010). Linear dose-response relations are typically observed for the

lignans (Nesbitt 1999; Hutchins 2000). Saturation in urine recovery has been observed with the

isoflavones (Setchell 2003a). Isoflavones and lignans have been measured in biologic matrices such

as plasma, serum, and urine by use of high performance liquid chromatography (HPLC) or gas

chromatography (GC) with various modes of detection (Hoikkala 2003; Prasain 2004). Liquid

chromatography coupled to tandem mass spectrometry (LC-MS/MS) methods that measure

isoflavones and lignans concentrations after deconjugation of glucuronides and sulfates are most

commonly used at present.

Data in NHANES. Phytoestrogens have been measured in NHANES since 1999. In NHANES

1999–2000, CDC scientists detected enterolactone in the highest concentration, and daidzein

was detected with the highest frequency among the six measured phytoestrogens (ValentinBlasini 2005). CDC’s Fourth National Report on Human Exposure to Environmental Chemicals

presented geometric means and selected percentiles (50th, 75th, 90th, and 95th) for concentrations

of phytoestrogens by age, sex, or race/ethnicity for participants in NHANES 1999–2000, 2001–

2002, and 2003–2004 (U.S. Centers for Disease Control and Prevention 2009).

Urinary daidzein, genistein, equol, ODMA, enterolactone, and enterodiol data presented in this

report were generated by use of LC-MS/MS using electrospray ionization (ESI) for NHANES

2003–2004 (Rybak 2008) and LC-MS/MS using atmospheric pressure photoionization (APPI)

for NHANES 2005–2006 (Parker 2011). Crossover studies comparing samples analyzed by

LC-ESI-MS/MS and LC-APPI-MS/MS demonstrated high correlation coefficients (r >0.99) and

regression slopes approximately equal to 1 and intercepts close to 0 (U.S. Centers for Disease

Control and Prevention 2011).

For more information about soy isoflavones, see the fact sheet from the National Institutes of

Health, Office of Dietary Supplements (http://ods.od.nih.gov/Health_Information/Information_

About_Individual_Dietary_Supplements.aspx).

Highlights

Urinary isoflavone and lignan concentrations in the U.S. population showed the following

demographic patterns and characteristics:

•	 No consistent patterns were observed with regard to age, gender, or race/ethnicity.

•	 Concentrations have been relatively similar from 1999–2006.

Urinary isoflavone and lignan concentrations showed only small variations by demographic

variables, such as age, gender, or race/ethnicity, or by survey cycle. However, as reported previously

(Valentin-Blasini 2005), we observed large differences in the concentration of different urinary

phytoestrogens. The enterolactone concentration was approximately one order of magnitude

higher than the concentrations of genistein, daidzein, and enterodiol, which in turn were

approximately one order of magnitude higher than the concentrations of equol and ODMA

(Figure H.4.a). These phytoestrogens were detected in >99% of all samples, with the exception of

ODMA, which was detected in only 93% of all samples.
4. Isoflavones and Lignans 365

Figure H.4.a. Geometric mean concentrations of urinary isoflavones and lignans in the U.S. population aged 6 years and older, 

National Health and Nutrition Examination Survey, 2003–2006. 

Error bars represent 95 percent confidence intervals. The y-axis is displayed on the logarithmic scale.

Detailed Observations

The selected observations mentioned below are derived from the uncorrected tables and figures

presented next. The NHANES population is of sufficient size to allow group comparisons based

on uncorrected data. Statements about categorical differences between demographic groups

noted below are based on non-overlapping confidence limits from univariate analysis without

adjusting for demographic variables (i.e., age, sex, race/ethnicity) or other determinants of these

urine concentrations (i.e., dietary intake, supplement usage, smoking, BMI). A multivariate

analysis may alter the size and statistical significance of these categorical differences. Furthermore,

additional significant differences of smaller magnitude may be present despite their lack of

mention here (e.g., if confidence limits slightly overlap or if differences are not statistically

significant before covariate adjustment has occurred). For a selection of citations of descriptive

NHANES papers related to these biochemical indicators of diet and nutrition, see Appendix G.

Geometric mean concentrations (NHANES 2003–2006):

•	 Urinary concentrations of daidzein (Table 4.3.a.1 and Figure 4.3.a), equol (Table 4.5.a.1

and Figure 4.5.a), and ODMA (Table 5.7.a.1 and Figure 5.7.1) were highest in children

and adolescents than for other age groups, while urinary concentrations of genistein

and the two lignans were similar across age groups (Tables 4.1.a.1, 4.9.a.1, 5.11.a.1 and

Figures 4.1.a, 4.9.a, 4.11.a).

•	 Males and females had similar phytoestrogen concentrations with the exception of

daidzein and genistein concentrations which were lower in females.

•	 Urinary concentrations of phytoestrogens were similar across the three race/ethnic groups,

with the exception of ODMA concentrations, which were lowest in Mexican Americans.

Changes in geometric mean concentrations across survey cycles:

•	 Urinary genistein, equol, ODMA, and enterolactone concentrations were similar across

the four survey cycles (Tables 4.1.b, 4.5.b, 4.7.b, and 4.11.b).

•	 Urinary daidzein concentrations were lower in 2001–2002 than in the other three

survey cycles (Table 4.3.b).

•	 Urinary enterodiol concentrations were lower in 1999-2000 than in the other three

survey cycles (Table 4.9.b).

1 

10 

100 

1000 

Genistein Daidzein Equol O-Desmethylangolensin Enterodiol Enterolactone 

Geometric mean (μg/L)
366

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.1.a.1. Urinary genistein: Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 29.9 (28.0 – 31.8) 1.51 (1.24 – 1.78) 2.45 (2.14 – 2.78) 26.1 (23.8 – 28.5) 523 (459 – 578) 852 (706 – 1,060) 5,122Age group6–11 years 36.0 (30.9 – 41.9) 3.05 (1.06 – 3.78) 4.20 (2.59 – 5.15) 31.7 (26.6 – 35.8) 414 (357 – 819) 846 (579 – 2,730) 692

12–19 years 34.4 (30.7 – 38.6) 2.39 (1.92 – 2.78) 3.33 (2.72 – 3.84) 27.6 (23.6 – 33.2) 514 (409 – 651) 946 (659 – 1,510) 1,422

20–39 years 28.5 (25.0 – 32.5) 1.54 (1.04 – 1.95) 2.27 (1.68 – 3.27) 23.7 (20.4 – 27.5) 516 (412 – 596) 810 (639 – 1,280) 1,137

40–59 years 28.1 (25.1 – 31.5) 1.33 (1.04 – 1.73) 2.17 (1.68 – 2.72) 26.2 (20.7 – 30.2) 589 (423 – 703) 767 (631 – 1,500) 901

60 years and older 29.5 (26.1 – 33.3) 1.15 (< LOD – 1.48) 2.16 (1.41 – 2.69) 27.5 (22.4 – 31.7) 435 (341 – 559) 794 (558 – 2,580) 970

GenderMales 32.9 (30.2 – 35.7) 1.96 (1.41 – 2.35) 3.22 (2.55 – 3.62) 28.5 (25.7 – 32.0) 544 (461 – 591) 805 (701 – 1,120) 2,496

Females 27.2 (24.9 – 29.9) 1.25 (1.05 – 1.53) 2.01 (1.76 – 2.31) 23.8 (20.8 – 27.0) 514 (398 – 618) 867 (654 – 1,150) 2,626

Race/ethnicityMexican Americans 29.3 (26.8 – 32.0) 1.67 (1.10 – 2.05) 2.47 (1.90 – 3.28) 25.8 (22.2 – 29.0) 570 (434 – 695) 929 (763 – 1,290) 1,287

Non-Hispanic Blacks 31.8 (27.1 – 37.3) 1.88 (1.21 – 2.30) 3.03 (2.34 – 3.53) 27.8 (23.0 – 34.7) 466 (387 – 743) 899 (642 – 1,260) 1,343

Non-Hispanic Whites 28.8 (26.7 – 31.1) 1.38 (1.13 – 1.65) 2.18 (1.84 – 2.71) 25.3 (22.3 – 28.3) 502 (417 – 589) 761 (682 – 1,100) 2,108

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
6−11 12−19 20−39 40−59 60+ 

0 20 40 60 

Urinary genistein (μg/L) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

60 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 4.1.a. Urinary genistein: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary genistein Urinary genistein (μg/L) (μg/L) 0 20 40 60 0 20 40 

6−11 12−19 20−39 

Females 

40−59 60+ 6−11 12−19 20−39 

Males 

40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

6−11 12−19 

Age (years) 

20−39 40−59 60+ 6−11 12−19 

Age (years) 

20−39 40−59 60+ 

4. Isoflavones and Lignans 367
368 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.1.a.2. Urinary genistein: Total population

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 

years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 29.9 (28.0 – 31.8) 4.18 (3.88 – 4.51) 26.1 (23.8 – 28.5) 274 (246 – 304) 5,122

6–11 years 36.0 (30.9 – 41.9) 6.11 (4.50 – 7.43) 31.7 (26.6 – 35.8) 276 (215 – 355) 692

12–19 years 34.4 (30.7 – 38.6) 4.87 (4.11 – 5.91) 27.6 (23.6 – 33.2) 303 (237 – 367) 1,422

20–39 years 28.5 (25.0 – 32.5) 4.25 (3.30 – 5.01) 23.7 (20.4 – 27.5) 237 (185 – 322) 1,137

40–59 years 28.1 (25.1 – 31.5) 3.76 (3.33 – 3.96) 26.2 (20.7 – 30.2) 307 (242 – 374) 901

60 years and older 29.5 (26.1 – 33.3) 4.09 (3.31 – 4.77) 27.5 (22.4 – 31.7) 244 (212 – 311) 970

Males

Total, 6 years and older 32.9 (30.2 – 35.7) 4.91 (4.35 – 5.39) 28.5 (25.7 – 32.0) 301 (247 – 337) 2,496

6–11 years 34.9 (28.9 – 42.1) 6.44 (4.51 – 8.48) 29.8 (22.4 – 35.8) 215 (177 – 369) 340

12–19 years 37.1 (31.3 – 44.0) 5.45 (4.48 – 6.96) 31.9 (24.2 – 42.5) 261 (209 – 402) 728

20–39 years 32.0 (27.8 – 36.7) 4.95 (3.48 – 5.71) 25.9 (21.5 – 32.0) 300 (197 – 397) 499

40–59 years 32.0 (26.9 – 38.0) 4.14 (3.42 – 5.17) 29.1 (21.7 – 34.2) 324 (227 – 510) 451

60 years and older 31.9 (26.6 – 38.3) 4.73 (3.78 – 5.83) 28.9 (20.6 – 36.6) 230 (183 – 337) 478

Females

Total, 6 years and older 27.2 (24.9 – 29.9) 3.73 (3.23 – 4.07) 23.8 (20.8 – 27.0) 253 (222 – 302) 2,626

6–11 years 37.2 (28.2 – 49.0) 5.55 (3.39 – 7.52) 34.9 (25.3 – 44.7) 278 (239 – 407) 352

12–19 years 31.7 (26.6 – 37.9) 3.85 (3.34 – 5.15) 24.3 (20.0 – 31.7) 321 (220 – 413) 694

20–39 years 25.5 (20.7 – 31.3) 3.81 (2.25 – 4.32) 22.1 (18.9 – 26.9) 208 (154 – 318) 638

40–59 years 24.9 (21.3 – 29.0) 3.14 (2.70 – 3.91) 20.4 (16.6 – 27.0) 256 (175 – 408) 450

60 years and older 27.7 (23.1 – 33.2) 3.34 (2.11 – 4.74) 26.6 (19.2 – 32.0) 243 (208 – 322) 492

Table 4.1.a.3. Urinary genistein: Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/L) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 29.3 (26.8 – 32.0) 4.38 (3.48 – 5.15) 25.8 (22.2 – 29.0) 301 (242 – 341) 1,287

6–11 years 32.4 (24.4 – 43.1) 5.65 (4.27 – 6.93) 27.5 (19.2 – 35.8) 293 (127 – 645) 231

12–19 years 35.6 (29.8 – 42.6) 5.60 (4.70 – 6.58) 30.7 (26.9 – 36.0) 315 (171 – 493) 445

20–39 years 26.8 (23.1 – 31.0) 4.03 (2.23 – 5.44) 21.3 (16.7 – 26.1) 325 (229 – 461) 282

40–59 years 29.1 (21.9 – 38.8) 4.18 (2.24 – 5.48) 27.5 (17.8 – 38.2) 253 (132 – 506) 157

60 years and older 25.9 (20.6 – 32.6) 3.09 (2.42 – 3.67) 29.8 (17.7 – 35.2) 228 (138 – 335) 172

Males

Total, 6 years and older 30.9 (26.4 – 36.3) 4.76 (3.89 – 5.84) 25.9 (21.4 – 31.5) 304 (200 – 457) 625

6–11 years 30.5 (22.1 – 42.0) 6.04 (3.33 – 7.64) 23.1 (17.9 – 34.9) 212 (101 – 566) 112

12–19 years 37.0 (30.3 – 45.3) 6.17 (4.86 – 7.61) 31.6 (26.1 – 40.7) 243 (160 – 424) 228

20–39 years 29.0 (21.3 – 39.5) 4.54 (2.37 – 5.97) 21.0 (15.5 – 36.1) 331 (185 – 646) 117

40–59 years 31.4 (19.5 – 50.6) 3.89† (1.51 – 6.76) 27.8 (13.3 – 43.9) 259† (86.0 – 4,840) 85

60 years and older 30.0 (17.7 – 50.9) 3.47† (1.78 – 5.40) 34.5 (16.9 – 56.7) 178† (97.8 – 2,730) 83

Females

Total, 6 years and older 27.5 (23.3 – 32.5) 3.76 (2.76 – 4.71) 25.2 (19.3 – 31.2) 286 (206 – 371) 662

6–11 years 34.6 (22.2 – 54.1) 5.17 (2.04 – 6.90) 34.0 (21.2 – 44.3) 303 (118 – 2,670) 119

12–19 years 34.2 (26.4 – 44.3) 5.03 (3.49 – 6.31) 29.4 (19.4 – 38.1) 407 (192 – 554) 217

20–39 years 24.4 (16.8 – 35.4) 3.41 (1.71 – 4.29) 20.3 (15.3 – 34.0) 251 (97.7 – 827) 165

40–59 years 26.9 (19.9 – 36.3) 4.15† (1.15 – 5.49) 26.5 (18.5 – 43.2) 199† (79.1 – 832) 72

60 years and older 23.0 (14.2 – 37.1) 2.53† (< LOD – 4.40) 17.8 (12.5 – 36.4) 258† (108 – 681) 89

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 369

Table 4.1.a.4. Urinary genistein: Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 31.8 (27.1 – 37.3) 5.01 (4.16 – 5.69) 27.8 (23.0 – 34.7) 269 (206 – 331) 1,343

6–11 years 38.4 (29.9 – 49.4) 5.60 (3.37 – 7.09) 34.7 (25.1 – 46.0) 311 (215 – 640) 207

12–19 years 42.7 (37.0 – 49.2) 6.66 (5.91 – 7.91) 35.3 (29.1 – 44.4) 286 (227 – 400) 496

20–39 years 29.0 (22.5 – 37.4) 5.04 (3.86 – 6.11) 24.7 (17.2 – 33.2) 198 (152 – 390) 249

40–59 years 32.2 (24.2 – 43.0) 4.30 (2.56 – 6.18) 29.9 (20.7 – 45.8) 318 (167 – 547) 231

60 years and older 22.9 (17.5 – 30.0) 3.42 (3.12 – 4.54) 20.6 (14.9 – 32.7) 171 (99.8 – 326) 160

Males

Total, 6 years and older 35.4 (30.1 – 41.7) 5.67 (4.64 – 6.71) 30.4 (26.5 – 36.3) 293 (214 – 401) 661

6–11 years 38.5 (26.8 – 55.3) 4.06† (1.87 – 7.03) 36.7 (18.6 – 54.7) 360† (205 – 747) 99

12–19 years 44.5 (36.0 – 55.0) 6.90 (4.87 – 8.70) 35.4 (27.4 – 48.1) 282 (193 – 844) 258

20–39 years 35.4 (26.1 – 48.0) 6.47 (4.28 – 9.07) 27.4 (18.8 – 43.5) 310 (158 – 413) 116

40–59 years 33.1 (24.0 – 45.8) 4.50 (2.29 – 7.00) 30.7 (20.4 – 47.7) 265 (153 – 434) 114

60 years and older 26.7 (20.0 – 35.6) 4.67† (3.31 – 6.20) 24.1 (17.1 – 35.7) 145† (110 – 525) 74

Females

Total, 6 years and older 29.1 (23.5 – 35.9) 4.46 (3.51 – 5.35) 24.9 (19.1 – 35.1) 249 (172 – 336) 682

6–11 years 38.4 (27.0 – 54.5) 6.52† (4.22 – 7.95) 31.4 (19.2 – 45.9) 272† (170 – 1,510) 108

12–19 years 40.9 (35.2 – 47.6) 6.54 (4.59 – 8.23) 35.2 (26.4 – 47.9) 286 (223 – 376) 238

20–39 years 24.6 (17.4 – 35.0) 4.47 (1.60 – 5.45) 20.2 (13.7 – 31.3) 165 (103 – 387) 133

40–59 years 31.5 (19.5 – 51.0) 3.75 (2.08 – 6.18) 27.6 (15.3 – 58.7) 349 (148 – 870) 117

60 years and older 20.8 (13.2 – 32.7) 3.22† (2.12 – 4.03) 18.2 (9.40 – 33.0) 170† (50.8 – 19,800) 86

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.1.a.5. Urinary genistein: Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic whites in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 28.8 (26.7 – 31.1) 4.00 (3.69 – 4.23) 25.3 (22.3 – 28.3) 257 (229 – 302) 2,108

6–11 years 34.9 (28.4 – 42.9) 5.95 (4.33 – 7.79) 29.1 (22.3 – 41.7) 247 (179 – 378) 193

12–19 years 32.8 (28.4 – 37.9) 4.48 (3.60 – 5.63) 24.7 (20.4 – 32.0) 298 (223 – 368) 378

20–39 years 26.9 (22.6 – 32.2) 3.82 (2.28 – 4.71) 22.8 (19.1 – 27.9) 218 (163 – 319) 494

40–59 years 27.0 (23.4 – 31.1) 3.44 (2.90 – 3.98) 26.0 (18.7 – 30.3) 307 (225 – 421) 448

60 years and older 30.2 (26.6 – 34.2) 4.23 (3.01 – 5.32) 28.0 (22.3 – 32.2) 242 (211 – 308) 595

Males

Total, 6 years and older 31.8 (28.5 – 35.5) 4.75 (4.15 – 5.31) 27.0 (22.4 – 31.9) 274 (227 – 340) 1,035

6–11 years 34.1 (25.0 – 46.4) 6.75† (4.40 – 9.87) 26.6 (18.1 – 42.0) 209† (154 – 400) 99

12–19 years 34.9 (27.3 – 44.7) 5.07 (4.12 – 7.35) 25.4 (19.0 – 41.1) 262 (205 – 392) 191

20–39 years 29.4 (23.6 – 36.6) 4.32 (2.26 – 5.49) 23.6 (18.7 – 32.9) 233 (155 – 418) 217

40–59 years 32.3 (26.3 – 39.7) 4.15 (3.03 – 5.45) 29.0 (21.1 – 37.1) 336 (225 – 590) 229

60 years and older 31.6 (25.7 – 38.8) 4.77 (3.79 – 6.83) 28.5 (19.5 – 39.4) 220 (172 – 341) 299

Females

Total, 6 years and older 26.2 (23.4 – 29.2) 3.30 (2.72 – 3.94) 23.6 (19.4 – 27.3) 243 (207 – 306) 1,073

6–11 years 35.8 (25.2 – 50.9) 4.98† (1.29 – 7.17) 39.3 (20.8 – 54.2) 271† (153 – 919) 94

12–19 years 30.7 (24.1 – 39.0) 3.62 (2.73 – 5.14) 22.4 (17.2 – 33.7) 311 (207 – 416) 187

20–39 years 24.7 (19.0 – 32.1) 3.18 (1.91 – 4.28) 22.2 (16.3 – 29.1) 210 (149 – 353) 277

40–59 years 22.5 (18.4 – 27.4) 2.93 (1.90 – 3.80) 18.3 (14.9 – 26.8) 232 (154 – 472) 219

60 years and older 29.1 (24.0 – 35.3) 3.67 (1.76 – 5.32) 27.5 (21.6 – 32.3) 244 (197 – 336) 296

† Estimate is subject to greater uncertainty due to small cell size. 
370 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.1.b. Urinary genistein: Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 24.4 (19.7 – 30.3) < LOD 27.0 (22.5 – 32.4) 563 (437 – 727) 2,557

 2001–2002 33.0 (30.1 – 36.2) 2.64 (2.24 – 2.89) 28.9 (26.8 – 31.7) 619 (536 – 720) 2,794

 2003–2004 31.1 (29.0 – 33.3) 2.63 (1.99 – 3.28) 26.2 (23.8 – 29.6) 525 (411 – 619) 2,594

 2005–2006 28.7 (25.8 – 32.0) 2.33 (1.93 – 2.74) 25.9 (20.9 – 29.6) 522 (438 – 590) 2,528

Age group

6–11 years

 1999–2000 27.6 (21.1 – 36.1) .922 (< LOD – 3.07) 31.7 (18.4 – 42.6) 376 (287 – 712) 331

 2001–2002 39.2 (33.4 – 46.0) 5.09 (3.88 – 6.13) 31.5 (25.8 – 39.2) 501 (329 – 1,150) 396

 2003–2004 33.6 (27.8 – 40.6) 4.40 (3.23 – 5.98) 29.2 (22.9 – 37.8) 351 (220 – 433) 341

 2005–2006 38.6 (29.8 – 49.9) 3.84 (< LOD – 5.12) 34.3 (25.3 – 42.4) 625 (402 – 2,960) 351

12–19 years

 1999–2000 43.7 (34.2 – 55.7) 2.85 (1.97 – 4.17) 44.9 (34.5 – 59.5) 543 (363 – 842) 754

 2001–2002 34.1 (27.2 – 42.8) 3.70 (2.00 – 5.17) 29.0 (26.0 – 32.8) 469 (380 – 708) 744

 2003–2004 34.7 (29.3 – 41.0) 3.24 (2.06 – 4.10) 29.0 (23.3 – 37.4) 522 (367 – 675) 729

 2005–2006 34.1 (28.8 – 40.5) 3.35 (2.39 – 4.19) 26.7 (20.5 – 35.4) 481 (404 – 1,070) 693

20–39 years

 1999–2000 28.7 (21.7 – 37.8) < LOD 28.5 (23.2 – 35.8) 704 (453 – 1,540) 536

 2001–2002 34.4 (28.2 – 41.9) 2.42 (1.37 – 3.16) 30.4 (25.3 – 38.5) 611 (489 – 797) 604

 2003–2004 29.1 (24.5 – 34.6) 2.41 (1.40 – 3.83) 24.9 (21.0 – 29.6) 436 (396 – 567) 554

 2005–2006 27.9 (22.7 – 34.4) 2.16 (1.42 – 3.27) 22.3 (18.6 – 29.0) 556 (412 – 938) 583

40–59 years

 1999–2000 15.5 (10.1 – 23.7) < LOD 21.3 (13.0 – 28.2) 464 (313 – 1,320) 420

 2001–2002 32.9 (27.6 – 39.4) 2.74 (.916 – 3.38) 29.3 (24.3 – 34.7) 719 (541 – 1,210) 531

 2003–2004 32.4 (27.6 – 38.1) 2.44 (1.75 – 3.38) 27.3 (20.8 – 33.1) 664 (535 – 1,110) 452

 2005–2006 24.5 (20.8 – 29.0) 2.06 (1.14 – 2.70) 24.9 (17.5 – 30.1) 466 (348 – 637) 449

60 years and older

 1999–2000 21.7 (16.9 – 27.9) < LOD 22.5 (17.7 – 30.3) 352 (279 – 904) 516

 2001–2002 26.7 (21.8 – 32.7) 1.94 (1.26 – 2.56) 25.0 (20.0 – 32.2) 496 (280 – 1,240) 519

 2003–2004 28.6 (24.2 – 33.9) 2.13 (1.26 – 2.66) 25.9 (20.1 – 34.2) 386 (314 – 575) 518

 2005–2006 30.3 (25.2 – 36.5) 2.18 (1.17 – 3.21) 28.8 (22.1 – 33.0) 469 (318 – 867) 452

Gender

Males

 1999–2000 29.8 (22.2 – 40.0) < LOD 31.8 (26.4 – 37.0) 684 (441 – 1,440) 1,222

 2001–2002 32.2 (27.9 – 37.2) 2.61 (1.94 – 3.33) 29.3 (25.6 – 33.7) 474 (348 – 727) 1,375

 2003–2004 33.7 (29.6 – 38.4) 3.33 (2.46 – 4.18) 27.3 (23.8 – 33.0) 561 (444 – 655) 1,244

 2005–2006 32.0 (28.6 – 36.0) 2.83 (2.34 – 3.45) 29.1 (23.0 – 33.8) 488 (411 – 622) 1,252

Females

 1999–2000 20.3 (17.0 – 24.2) < LOD 23.1 (20.2 – 26.2) 442 (345 – 674) 1,335

 2001–2002 33.7 (30.9 – 36.8) 2.62 (2.25 – 2.87) 28.6 (26.3 – 31.9) 663 (602 – 811) 1,419

 2003–2004 28.7 (25.5 – 32.4) 2.05 (1.71 – 2.65) 25.0 (22.5 – 28.4) 466 (362 – 621) 1,350

 2005–2006 25.9 (22.3 – 29.9) 1.93 (1.58 – 2.34) 22.3 (17.8 – 27.4) 524 (413 – 694) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 31.1 (25.1 – 38.5) .628 (< LOD – 2.04) 30.0 (25.2 – 37.4) 572 (471 – 1,550) 819

 2001–2002 28.3 (22.0 – 36.4) 2.80 (1.56 – 3.90) 25.4 (19.9 – 32.4) 423 (340 – 543) 679

 2003–2004 31.1 (27.5 – 35.2) 3.38 (2.23 – 4.24) 25.2 (19.2 – 32.2) 643 (566 – 865) 653

 2005–2006 27.6 (24.4 – 31.2) 2.11 (1.23 – 2.93) 26.3 (21.7 – 29.8) 412 (333 – 626) 634

Non-Hispanic Blacks

 1999–2000 26.5 (19.0 – 36.9) < LOD 32.8 (24.6 – 41.4) 456 (363 – 766) 597

 2001–2002 37.9 (27.3 – 52.6) 2.49 (1.53 – 4.06) 35.9 (23.9 – 51.2) 598 (446 – 1,300) 692

 2003–2004 32.6 (24.2 – 44.0) 3.00 (2.00 – 4.16) 27.7 (19.4 – 44.9) 506 (334 – 875) 681

 2005–2006 31.0 (26.7 – 36.1) 3.00 (2.16 – 3.55) 27.8 (23.1 – 34.9) 452 (372 – 883) 662

Non-Hispanic Whites

 1999–2000 23.7 (19.1 – 29.4) < LOD 25.6 (22.0 – 32.0) 564 (413 – 742) 901

 2001–2002 30.9 (27.7 – 34.3) 2.43 (2.03 – 2.75) 27.3 (24.5 – 30.7) 623 (521 – 746) 1,211

 2003–2004 30.9 (28.4 – 33.6) 2.34 (1.71 – 3.29) 26.2 (22.8 – 30.9) 501 (384 – 619) 1,069

 2005–2006 26.9 (23.6 – 30.6) 2.10 (1.58 – 2.57) 23.7 (19.0 – 29.0) 500 (397 – 623) 1,039

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
H H 

H H 

50 

60 

H H

H 

H 

H 

H H 

H 

H 

H 

H H 

H 

H 

H H 

H 

H 

H

H 

H 

H H H 

H 

H 

H H 

H H H 

H 

H H H H 

0 

1000 

2000 

3000 

95th Percentile 

H

H 

H 

H H H H H H H H H 

H

H H H H 

H 

H H H 

H 

H 

H H 

H H H H H 

H H 

Figure 4.1.b. Urinary genistein: Concentrations by survey cycle 

Selected percentiles in μg/L (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006 

5th Percentile 50th Percentile

40 

30 

20 

10 

8 

6 

4 

2 

0 

H H H 

H 

H 

H 

H 

H H 

H H H 

H 

H 

H H 

H H 

H 

H 

H 

H

H H 

H H H 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

4. Isoflavones and Lignans 371
372

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.2.a.1. Urinary genistein (creatinine corrected): Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 28.5 (26.9 – 30.2) 2.22 (1.97 – 2.46) 3.14 (2.83 – 3.45) 23.8 (21.6 – 26.1) 534 (438 – 627) 910 (796 – 1,210) 5,122Age group6–11 years 39.0 (33.7 – 45.1) 3.68 (1.15 – 4.62) 5.09 (3.51 – 6.16) 34.5 (27.4 – 38.3) 626 (412 – 1,060) 1,240 (740 – 2,140) 692

12–19 years 25.6 (23.0 – 28.5) 2.25 (1.60 – 2.74) 3.36 (2.73 – 3.66) 20.4 (17.8 – 24.8) 367 (293 – 440) 730 (439 – 1,120) 1,422

20–39 years 24.3 (21.8 – 27.1) 2.14 (1.81 – 2.43) 2.81 (2.37 – 3.50) 20.7 (17.8 – 23.6) 355 (291 – 530) 749 (563 – 1,220) 1,137

40–59 years 28.4 (25.2 – 32.1) 1.89 (1.35 – 2.35) 2.66 (2.10 – 3.14) 23.6 (19.1 – 27.8) 645 (445 – 1,020) 1,210 (779 – 1,970) 901

60 years and older 34.5 (31.4 – 38.0) 2.97 (< LOD – 3.38) 3.82 (3.36 – 4.47) 28.6 (24.5 – 32.6) 576 (464 – 668) 913 (661 – 1,470) 970

GenderMales 26.1 (24.0 – 28.3) 2.12 (1.80 – 2.48) 3.03 (2.60 – 3.42) 22.1 (19.5 – 24.9) 422 (348 – 557) 811 (629 – 1,140) 2,496

Females 31.1 (28.3 – 34.1) 2.35 (1.97 – 2.77) 3.20 (2.80 – 3.76) 25.8 (22.9 – 28.1) 617 (448 – 778) 1,000 (853 – 1,610) 2,626

Race/ethnicityMexican Americans 26.4 (24.2 – 28.8) 1.87 (1.19 – 2.49) 2.97 (2.24 – 3.47) 22.4 (19.5 – 24.6) 441 (355 – 656) 955 (723 – 1,330) 1,287

Non-Hispanic Blacks 22.3 (19.6 – 25.5) 2.02 (1.38 – 2.51) 2.76 (2.31 – 3.16) 19.1 (15.7 – 22.2) 319 (261 – 488) 561 (489 – 793) 1,343

Non-Hispanic Whites 29.3 (27.3 – 31.4) 2.21 (1.84 – 2.54) 3.08 (2.67 – 3.58) 24.9 (22.1 – 27.7) 594 (437 – 687) 915 (834 – 1,250) 2,108

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
6−11 12−19 20−39 40−59 60+ 

0 20 40 60 80 

Urinary genistein (μg/g creatinine) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 4.2.a. Urinary genistein (creatinine corrected): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary genistein Urinary genistein (μg/g creatinine) (μg/g creatinine) 0 20 40 60 80 0 20 40 60 80 

Non−Hispanic Blacks 

6−11 12−19 20−39 40−59 60+ 

Females 

6−11 12−19 20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

6−11 12−19 20−39 40−59 60+ 

Males 

6−11 12−19 20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

4. Isoflavones and Lignans 373
374 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.2.a.2. Urinary genistein (creatinine corrected): Total population

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 28.5 (26.9 – 30.2) 4.53 (4.29 – 4.79) 23.8 (21.6 – 26.1) 236 (210 – 270) 5,122

6–11 years 39.0 (33.7 – 45.1) 6.68 (5.55 – 8.43) 34.5 (27.4 – 38.3) 271 (216 – 388) 692

12–19 years 25.6 (23.0 – 28.5) 4.36 (3.90 – 4.67) 20.4 (17.8 – 24.8) 189 (151 – 236) 1,422

20–39 years 24.3 (21.8 – 27.1) 4.15 (3.81 – 4.55) 20.7 (17.8 – 23.6) 184 (144 – 236) 1,137

40–59 years 28.4 (25.2 – 32.1) 4.04 (3.52 – 4.65) 23.6 (19.1 – 27.8) 270 (207 – 415) 901

60 years and older 34.5 (31.4 – 38.0) 5.51 (4.85 – 6.21) 28.6 (24.5 – 32.6) 287 (226 – 398) 970

Males

Total, 6 years and older 26.1 (24.0 – 28.3) 4.29 (4.03 – 4.56) 22.1 (19.5 – 24.9) 205 (179 – 237) 2,496

6–11 years 35.0 (28.8 – 42.4) 6.30 (5.10 – 7.99) 29.8 (21.2 – 38.2) 272 (158 – 503) 340

12–19 years 25.2 (21.1 – 30.0) 4.38 (3.66 – 4.66) 20.3 (17.0 – 29.0) 154 (128 – 256) 728

20–39 years 23.3 (20.8 – 26.1) 3.96 (3.39 – 4.38) 20.0 (16.0 – 24.4) 204 (149 – 244) 499

40–59 years 25.4 (21.6 – 29.8) 3.68 (3.27 – 4.51) 20.2 (16.8 – 25.5) 228 (155 – 386) 451

60 years and older 29.4 (24.8 – 34.7) 5.20 (4.11 – 6.32) 25.0 (20.0 – 30.4) 200 (151 – 259) 478

Females

Total, 6 years and older 31.1 (28.3 – 34.1) 4.80 (4.35 – 5.45) 25.8 (22.9 – 28.1) 274 (230 – 320) 2,626

6–11 years 43.8 (33.4 – 57.4) 8.16 (4.38 – 10.4) 37.7 (26.4 – 50.0) 270 (212 – 798) 352

12–19 years 26.1 (22.5 – 30.3) 4.35 (3.72 – 5.23) 20.6 (16.5 – 24.8) 208 (164 – 269) 694

20–39 years 25.3 (20.9 – 30.7) 4.50 (3.83 – 5.53) 21.0 (17.6 – 26.9) 170 (124 – 289) 638

40–59 years 31.7 (26.2 – 38.3) 4.34 (2.99 – 5.61) 26.6 (21.3 – 32.6) 340 (210 – 631) 450

60 years and older 39.2 (33.9 – 45.4) 5.70 (4.76 – 6.64) 31.6 (25.8 – 39.0) 361 (289 – 530) 492

Table 4.2.a.3. Urinary genistein (creatinine corrected): Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for Mexican Americans in 

the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 26.4 (24.2 – 28.8) 4.25 (3.81 – 4.70) 22.4 (19.5 – 24.6) 212 (186 – 275) 1,287

6–11 years 40.7 (31.0 – 53.5) 7.48 (5.51 – 9.00) 31.6 (22.8 – 44.7) 304 (161 – 1,100) 231

12–19 years 27.5 (23.7 – 32.0) 5.58 (4.31 – 6.56) 22.4 (18.9 – 26.4) 208 (139 – 366) 445

20–39 years 21.6 (18.6 – 25.2) 3.65 (2.96 – 4.28) 16.2 (13.1 – 20.9) 204 (138 – 255) 282

40–59 years 26.7 (20.1 – 35.4) 3.71 (2.37 – 4.69) 25.4 (16.8 – 33.8) 229 (131 – 629) 157

60 years and older 32.0 (23.9 – 42.9) 5.10 (2.91 – 6.94) 31.2 (22.8 – 40.4) 233 (141 – 535) 172

Males

Total, 6 years and older 24.4 (20.6 – 28.9) 4.10 (3.50 – 4.54) 22.2 (17.2 – 26.4) 203 (136 – 275) 625

6–11 years 36.6 (25.7 – 52.1) 7.40 (5.50 – 9.04) 30.2 (19.7 – 43.0) 251 (129 – 659) 112

12–19 years 26.8 (21.9 – 32.8) 5.68 (4.54 – 6.56) 23.0 (16.8 – 30.7) 151 (116 – 347) 228

20–39 years 21.1 (15.6 – 28.5) 3.54 (2.60 – 4.32) 17.2 (12.4 – 23.3) 199 (112 – 328) 117

40–59 years 23.0 (14.4 – 36.9) 3.31† (1.22 – 4.36) 20.9 (8.19 – 31.2) 192† (92.0 – 2,070) 85

60 years and older 26.7 (16.1 – 44.4) 4.18† (1.75 – 7.13) 29.0 (10.9 – 49.6) 159† (59.4 – 4,830) 83

Females

Total, 6 years and older 28.7 (25.0 – 32.9) 4.59 (3.67 – 5.88) 22.9 (18.5 – 27.1) 262 (189 – 391) 662

6–11 years 45.6 (31.5 – 66.2) 7.46 (4.51 – 9.99) 37.3 (20.3 – 68.7) 311 (166 – 1,460) 119

12–19 years 28.2 (23.4 – 34.1) 5.47 (2.84 – 7.19) 21.7 (17.8 – 28.9) 269 (155 – 425) 217

20–39 years 22.3 (15.8 – 31.3) 3.60 (2.14 – 6.28) 15.8 (12.0 – 23.4) 199 (116 – 728) 165

40–59 years 31.3 (24.2 – 40.4) 4.10† (.565 – 6.37) 32.5 (18.1 – 44.1) 296† (151 – 594) 72

60 years and older 37.0 (22.8 – 60.0) 5.54† (< LOD – 8.83) 31.6 (13.4 – 82.7) 261† (142 – 745) 89

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 375

Table 4.2.a.4. Urinary genistein (creatinine corrected): Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic blacks 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 22.3 (19.6 – 25.5) 3.95 (3.34 – 4.63) 19.1 (15.7 – 22.2) 159 (137 – 211) 1,343

6–11 years 36.1 (28.1 – 46.3) 6.36 (4.62 – 7.24) 25.2 (22.0 – 37.0) 325 (198 – 811) 207

12–19 years 24.5 (21.6 – 27.9) 4.32 (3.87 – 5.01) 22.0 (16.7 – 25.6) 150 (125 – 214) 496

20–39 years 17.9 (14.7 – 21.9) 3.49 (2.75 – 4.31) 14.0 (11.3 – 19.5) 123 (82.7 – 209) 249

40–59 years 23.4 (18.7 – 29.3) 3.30 (2.54 – 4.71) 21.4 (17.4 – 26.3) 173 (128 – 458) 231

60 years and older 20.4 (16.4 – 25.5) 4.39 (3.33 – 4.93) 17.5 (11.4 – 22.8) 130 (84.1 – 218) 160

Males

Total, 6 years and older 20.7 (17.9 – 23.8) 3.40 (2.80 – 4.38) 17.6 (13.9 – 21.4) 173 (137 – 213) 661

6–11 years 36.4 (25.8 – 51.2) 4.60† (3.12 – 7.24) 24.9 (19.2 – 47.2) 396† (214 – 869) 99

12–19 years 23.8 (19.6 – 28.8) 3.95 (3.32 – 4.73) 21.2 (14.5 – 25.8) 159 (122 – 246) 258

20–39 years 17.0 (13.0 – 22.1) 3.20 (2.32 – 3.87) 12.6 (9.92 – 20.3) 150 (86.4 – 209) 116

40–59 years 18.9 (13.8 – 26.0) 2.97 (1.59 – 4.57) 17.4 (9.55 – 25.7) 140 (86.9 – 359) 114

60 years and older 19.6 (14.6 – 26.3) 3.86† (2.60 – 5.06) 18.3 (11.1 – 25.0) 112† (65.3 – 220) 74

Females

Total, 6 years and older 23.8 (19.8 – 28.6) 4.65 (3.49 – 5.61) 20.4 (16.4 – 25.3) 156 (123 – 244) 682

6–11 years 35.8 (24.8 – 51.6) 6.98† (5.89 – 8.65) 25.0 (20.5 – 37.1) 261† (113 – 1,290) 108

12–19 years 25.3 (21.7 – 29.4) 4.87 (3.83 – 5.77) 22.7 (15.5 – 28.5) 143 (105 – 292) 238

20–39 years 18.8 (14.2 – 24.8) 3.79 (2.53 – 5.95) 14.3 (10.5 – 21.9) 119 (77.3 – 252) 133

40–59 years 27.9 (18.7 – 41.8) 3.62 (2.57 – 5.58) 24.7 (17.9 – 34.9) 221 (114 – 570) 117

60 years and older 21.0 (14.5 – 30.3) 4.51† (2.75 – 6.49) 16.5 (9.90 – 29.0) 134† (83.9 – 254) 86

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.2.a.5. Urinary genistein (creatinine corrected): Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic whites 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 29.3 (27.3 – 31.4) 4.55 (4.17 – 4.93) 24.9 (22.1 – 27.7) 241 (209 – 291) 2,108

6–11 years 37.8 (31.2 – 45.8) 6.34 (5.11 – 8.41) 34.8 (24.5 – 43.0) 255 (175 – 577) 193

12–19 years 25.8 (22.3 – 29.7) 4.33 (3.67 – 4.93) 19.5 (16.7 – 26.0) 181 (143 – 247) 378

20–39 years 24.8 (21.4 – 28.9) 4.16 (3.52 – 4.76) 21.7 (18.1 – 28.3) 181 (134 – 289) 494

40–59 years 29.0 (25.3 – 33.2) 4.00 (3.18 – 4.90) 23.6 (17.7 – 30.3) 273 (202 – 477) 448

60 years and older 36.0 (32.8 – 39.6) 5.83 (4.85 – 6.54) 30.0 (26.4 – 34.1) 292 (224 – 431) 595

Males

Total, 6 years and older 26.6 (23.9 – 29.5) 4.40 (3.87 – 4.86) 22.7 (19.4 – 26.2) 204 (169 – 261) 1,035

6–11 years 33.0 (23.9 – 45.6) 5.93† (4.89 – 8.18) 24.8 (17.3 – 40.0) 195† (126 – 945) 99

12–19 years 24.9 (19.3 – 32.3) 4.34 (3.13 – 5.24) 18.9 (14.5 – 31.4) 144 (121 – 311) 191

20–39 years 23.3 (19.3 – 28.2) 3.96 (2.52 – 4.69) 20.7 (15.9 – 28.7) 189 (105 – 339) 217

40–59 years 27.1 (22.5 – 32.5) 3.85 (3.22 – 4.95) 21.3 (16.4 – 27.9) 244 (155 – 623) 229

60 years and older 29.4 (24.5 – 35.4) 5.47 (3.88 – 6.92) 26.2 (20.0 – 33.5) 190 (147 – 263) 299

Females

Total, 6 years and older 32.3 (29.0 – 35.9) 4.69 (4.14 – 5.40) 27.4 (23.5 – 32.6) 289 (227 – 361) 1,073

6–11 years 44.4 (31.3 – 62.8) 8.19† (2.79 – 11.4) 43.0 (26.0 – 58.2) 266† (164 – 1,300) 94

12–19 years 26.7 (21.7 – 32.8) 4.15 (3.63 – 5.22) 20.5 (15.8 – 26.1) 203 (156 – 342) 187

20–39 years 26.5 (20.8 – 33.7) 4.51 (3.50 – 5.62) 22.3 (18.1 – 33.0) 172 (126 – 300) 277

40–59 years 31.1 (25.1 – 38.6) 3.92 (2.63 – 5.82) 25.6 (17.7 – 34.1) 317 (180 – 675) 219

60 years and older 42.2 (36.1 – 49.3) 6.05 (4.82 – 7.49) 33.7 (27.6 – 42.2) 404 (291 – 567) 296

† Estimate is subject to greater uncertainty due to small cell size. 
376 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.2.b. Urinary genistein (creatinine corrected): Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 22.3 (17.7 – 28.1) <LOD 23.8 (18.9 – 28.7) 380 (341 – 523) 2,557

 2001–2002 30.9 (28.5 – 33.6) 3.52 (3.07 – 3.80) 25.8 (23.5 – 29.2) 426 (375 – 491) 2,794

 2003–2004 29.1 (27.3 – 31.0) 3.39 (2.80 – 3.69) 24.5 (21.4 – 27.4) 507 (399 – 619) 2,594

 2005–2006 28.0 (25.3 – 31.0) 2.98 (2.42 – 3.44) 23.2 (20.4 – 26.4) 576 (423 – 759) 2,528

Age group

6–11 years

 1999–2000 28.3 (21.1 – 37.9) 1.84 (<LOD – 3.04) 27.8 (15.8 – 41.1) 489 (282 – 794) 331

 2001–2002 44.5 (37.0 – 53.5) 6.82 (4.89 – 8.11) 37.7 (30.0 – 48.3) 489 (276 – 934) 396

 2003–2004 35.8 (29.7 – 43.0) 5.15 (3.19 – 6.46) 34.7 (25.3 – 43.1) 293 (175 – 1,130) 341

 2005–2006 42.5 (33.1 – 54.6) 4.86 (< LOD – 6.37) 34.0 (24.2 – 40.9) 985 (580 – 1,850) 351

12–19 years

 1999–2000 29.4 (22.3 – 38.8) 2.12 (.684 – 3.24) 31.9 (24.3 – 41.6) 331 (199 – 1,360) 754

 2001–2002 26.3 (21.3 – 32.5) 3.43 (2.34 – 4.13) 21.0 (18.1 – 26.5) 321 (294 – 487) 744

 2003–2004 25.9 (21.8 – 30.9) 3.45 (2.56 – 4.00) 21.8 (17.0 – 28.6) 366 (322 – 464) 729

 2005–2006 25.3 (22.1 – 29.0) 3.32 (2.25 – 3.67) 19.5 (16.3 – 23.8) 367 (238 – 617) 693

20–39 years

 1999–2000 22.7 (17.3 – 29.9) <LOD 22.8 (17.0 – 27.2) 417 (355 – 738) 536

 2001–2002 27.8 (23.8 – 32.4) 3.29 (2.22 – 3.92) 22.9 (18.7 – 29.8) 379 (329 – 476) 604

 2003–2004 24.5 (21.9 – 27.4) 2.97 (2.55 – 3.69) 19.7 (17.3 – 23.4) 320 (271 – 557) 554

 2005–2006 24.1 (19.8 – 29.3) 2.55 (1.85 – 3.76) 21.3 (16.5 – 27.5) 447 (288 – 734) 583

40–59 years

 1999–2000 15.7 (10.3 – 24.1) <LOD 16.3 (12.5 – 26.8) 374 (246 – 894) 420

 2001–2002 32.7 (27.8 – 38.6) 3.54 (2.26 – 4.12) 28.7 (24.2 – 32.1) 461 (377 – 1,260) 531

 2003–2004 31.1 (26.4 – 36.6) 3.18 (1.96 – 3.75) 24.9 (19.7 – 29.8) 676 (496 – 1,670) 452

 2005–2006 26.1 (21.5 – 31.7) 2.46 (1.82 – 2.97) 21.5 (16.8 – 29.2) 578 (326 – 1,220) 449

60 years and older

 1999–2000 26.1 (21.7 – 31.3) <LOD 27.3 (20.4 – 35.9) 371 (252 – 691) 516

 2001–2002 31.6 (25.8 – 38.8) 3.00 (2.36 – 3.76) 25.5 (20.7 – 33.3) 491 (323 – 1,310) 519

 2003–2004 33.9 (29.7 – 38.7) 3.39 (2.78 – 4.33) 29.5 (23.8 – 34.6) 539 (444 – 754) 518

 2005–2006 35.2 (30.3 – 40.8) 4.13 (3.34 – 5.27) 27.9 (23.0 – 35.0) 589 (402 – 776) 452

Gender

Males

 1999–2000 23.3 (16.8 – 32.3) <LOD 23.8 (17.7 – 31.9) 510 (329 – 893) 1,222

 2001–2002 26.2 (23.1 – 29.8) 3.62 (2.52 – 4.01) 22.0 (19.4 – 26.2) 341 (282 – 427) 1,375

 2003–2004 26.4 (22.8 – 30.5) 3.40 (2.66 – 3.63) 21.5 (17.6 – 26.3) 414 (346 – 574) 1,244

 2005–2006 25.8 (23.4 – 28.4) 2.68 (1.98 – 3.40) 22.7 (19.3 – 26.2) 430 (319 – 629) 1,252

Females

 1999–2000 21.3 (17.5 – 26.0) <LOD 23.1 (17.5 – 29.2) 357 (309 – 432) 1,335

 2001–2002 36.2 (32.8 – 39.9) 3.50 (3.02 – 3.85) 29.5 (25.4 – 34.1) 540 (430 – 756) 1,419

 2003–2004 31.9 (28.7 – 35.5) 3.29 (2.60 – 4.33) 27.1 (23.6 – 31.6) 545 (410 – 775) 1,350

 2005–2006 30.3 (25.8 – 35.5) 3.07 (2.34 – 3.76) 23.5 (20.1 – 29.4) 658 (446 – 912) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 28.4 (23.3 – 34.7) 1.40 (<LOD – 2.74) 27.9 (22.5 – 35.0) 557 (322 – 1,290) 819

 2001–2002 26.6 (21.6 – 32.9) 3.75 (2.96 – 4.09) 20.9 (16.1 – 28.7) 371 (280 – 484) 679

 2003–2004 28.0 (24.8 – 31.8) 3.35 (2.29 – 3.99) 23.4 (18.8 – 28.1) 594 (426 – 884) 653

 2005–2006 24.9 (22.1 – 28.0) 2.66 (1.46 – 3.47) 21.7 (18.1 – 23.7) 334 (277 – 520) 634

Non-Hispanic Blacks

 1999–2000 17.0 (12.2 – 23.6) <LOD 19.4 (15.7 – 26.1) 284 (229 – 449) 597

 2001–2002 26.4 (19.2 – 36.4) 2.91 (2.56 – 3.44) 22.7 (16.4 – 33.4) 369 (237 – 788) 692

 2003–2004 23.0 (18.1 – 29.1) 3.11 (2.73 – 3.33) 20.4 (14.3 – 27.3) 304 (210 – 547) 681

 2005–2006 21.7 (18.8 – 25.1) 2.58 (1.59 – 3.17) 18.5 (14.9 – 21.5) 350 (247 – 548) 662

Non-Hispanic Whites

 1999–2000 23.3 (18.5 – 29.3) <LOD 25.6 (19.4 – 31.7) 380 (346 – 574) 901

 2001–2002 30.5 (28.1 – 33.0) 3.54 (2.96 – 3.81) 25.2 (23.3 – 28.7) 424 (376 – 494) 1,211

 2003–2004 30.5 (28.1 – 33.1) 3.37 (2.66 – 3.83) 26.3 (21.7 – 31.4) 544 (362 – 747) 1,069

 2005–2006 28.2 (25.1 – 31.8) 2.98 (2.18 – 3.59) 23.5 (20.0 – 29.0) 615 (427 – 810) 1,039

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
5th Percentile 50th Percentile 95th Percentile 1000 

500 

0 

50 

40 

30 

20 

10 

10 

8 

6 

4 

2 

0 

2000 

1500 

H H 

H H 

H H 

H 

H 

H H H H H H 

H H H

H H H H 

H H 

H 

H 

H 

H 

H H 

H H H H H 

H H 

H 

H H H 

H 

H 

H H 

H 

H H 

H 

H 

H H H H 

H H H H 

H 

H 

H 

H 

H

H 

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H 

H 

H 

H 

H H H 

H 

H H 

H 

H 

H 

H 

H H H H H H 

H H 

H 

H H H 

H 

H 

H H H 

H 

H H 

H 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

Figure 4.2.b. Urinary genistein (creatinine corrected): 

Concentrations by survey cycle 

Selected percentiles in μg/g creatinine (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006

4. Isoflavones and Lignans 377
378

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.3.a.1. Urinary daidzein: Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 66.6 (62.1 – 71.5) 3.31 (2.74 – 3.72) 5.35 (4.25 – 6.22) 60.4 (54.7 – 65.9) 1,170 (1,000 – 1,290) 1,850 (1,590 – 2,200) 5,122

Age group6–11 years 89.4 (77.7 – 103) 7.38 (5.07 – 8.35) 10.2 (7.62 – 13.1) 68.4 (59.2 – 86.6) 1,180 (996 – 1,870) 2,250 (1,550 – 6,320) 692

12–19 years 91.6 (80.5 – 104) 5.85 (3.92 – 6.63) 9.07 (6.69 – 9.60) 77.3 (65.0 – 94.5) 1,310 (989 – 1,760) 2,180 (1,710 – 3,350) 1,422

20–39 years 61.6 (53.3 – 71.3) 3.32 (1.80 – 3.99) 4.82 (3.43 – 6.14) 54.3 (47.2 – 65.9) 1,210 (835 – 1,560) 1,860 (1,490 – 2,430) 1,137

40–59 years 60.9 (54.9 – 67.6) 3.04 (1.89 – 3.48) 4.56 (3.42 – 5.90) 56.5 (47.0 – 65.5) 1,120 (893 – 1,340) 1,510 (1,270 – 3,510) 901

60 years and older 60.9 (52.7 – 70.5) 2.24 (1.47 – 3.58) 4.31 (2.73 – 6.34) 60.5 (48.9 – 73.4) 839 (709 – 1,310) 1,600 (1,210 – 2,660) 970

GenderMales 73.8 (67.2 – 81.1) 3.63 (2.74 – 4.56) 6.35 (4.53 – 7.62) 66.0 (58.0 – 73.7) 1,200 (1,060 – 1,350) 1,750 (1,520 – 2,220) 2,496

Females 60.4 (55.3 – 66.0) 3.04 (2.39 – 3.41) 4.47 (3.72 – 5.61) 55.5 (49.5 – 61.5) 1,000 (836 – 1,270) 1,910 (1,490 – 2,630) 2,626

Race/ethnicityMexican Americans 59.0 (54.1 – 64.4) 3.07 (2.14 – 3.68) 4.71 (3.62 – 5.66) 48.6 (44.8 – 56.8) 1,350 (1,130 – 1,500) 1,800 (1,560 – 2,450) 1,287

Non-Hispanic Blacks 78.4 (67.6 – 90.9) 4.48 (3.48 – 5.77) 7.05 (5.74 – 7.82) 72.3 (61.3 – 85.2) 1,180 (886 – 1,610) 2,220 (1,500 – 3,390) 1,343

Non-Hispanic Whites 63.9 (58.7 – 69.6) 3.03 (2.26 – 3.41) 4.66 (3.69 – 6.11) 58.5 (52.0 – 65.3) 1,040 (930 – 1,250) 1,600 (1,420 – 2,150) 2,108
6−11 12−19 20−39 40−59 60+ 

0 50 100 150 200 

Urinary daidzein (μg/L) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

200 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 4.3.a. Urinary daidzein: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary daidzein Urinary daidzein (μg/L) (μg/L) 0 50 100 150 200 0 50 100 150 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

4. Isoflavones and Lignans 379
380 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.3.a.2. Urinary daidzein: Total population

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 

years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 66.6 (62.1 – 71.5) 8.65 (7.74 – 9.48) 60.4 (54.7 – 65.9) 613 (525 – 684) 5,122

6–11 years 89.4 (77.7 – 103) 15.7 (12.2 – 18.1) 68.4 (59.2 – 86.6) 653 (619 – 916) 692

12–19 years 91.6 (80.5 – 104) 14.5 (11.8 – 15.8) 77.3 (65.0 – 94.5) 834 (659 – 969) 1,422

20–39 years 61.6 (53.3 – 71.3) 8.20 (6.00 – 10.4) 54.3 (47.2 – 65.9) 571 (422 – 752) 1,137

40–59 years 60.9 (54.9 – 67.6) 7.71 (6.35 – 8.67) 56.5 (47.0 – 65.5) 572 (410 – 807) 901

60 years and older 60.9 (52.7 – 70.5) 7.92 (6.54 – 9.19) 60.5 (48.9 – 73.4) 471 (399 – 618) 970

Males

Total, 6 years and older 73.8 (67.2 – 81.1) 9.92 (8.68 – 11.9) 66.0 (58.0 – 73.7) 695 (589 – 786) 2,496

6–11 years 87.3 (72.9 – 105) 17.5 (12.2 – 21.0) 64.0 (51.5 – 91.4) 874 (497 – 1,150) 340

12–19 years 103 (85.2 – 124) 17.3 (13.9 – 19.4) 86.6 (64.8 – 107) 863 (526 – 1,320) 728

20–39 years 70.4 (58.8 – 84.2) 9.80 (5.43 – 12.8) 65.3 (51.7 – 75.0) 729 (544 – 968) 499

40–59 years 68.4 (57.9 – 80.8) 8.55 (7.15 – 9.37) 66.2 (47.7 – 84.7) 671 (409 – 930) 451

60 years and older 64.4 (52.0 – 79.9) 9.16 (7.75 – 11.8) 57.7 (43.8 – 78.5) 561 (417 – 749) 478

Females

Total, 6 years and older 60.4 (55.3 – 66.0) 7.79 (6.41 – 8.76) 55.5 (49.5 – 61.5) 507 (431 – 619) 2,626

6–11 years 91.6 (72.4 – 116) 14.3 (9.67 – 17.9) 78.1 (57.3 – 99.4) 643 (455 – 882) 352

12–19 years 81.0 (69.6 – 94.3) 11.1 (9.30 – 14.5) 71.1 (59.6 – 93.6) 812 (604 – 936) 694

20–39 years 54.0 (44.1 – 66.2) 7.31 (5.72 – 9.03) 47.9 (38.1 – 63.9) 383 (309 – 585) 638

40–59 years 54.6 (47.9 – 62.3) 6.98 (4.64 – 8.60) 48.2 (40.6 – 58.2) 511 (395 – 736) 450

60 years and older 58.3 (48.5 – 70.2) 7.04 (4.21 – 8.11) 60.9 (46.8 – 80.2) 403 (362 – 562) 492

Table 4.3.a.3. Urinary daidzein: Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/L) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 59.0 (54.1 – 64.4) 7.94 (6.47 – 8.95) 48.6 (44.8 – 56.8) 671 (496 – 848) 1,287

6–11 years 78.3 (61.0 – 100) 16.6 (11.6 – 18.1) 64.5 (51.3 – 83.2) 588 (321 – 2,270) 231

12–19 years 87.3 (72.5 – 105) 12.3 (8.90 – 16.5) 74.6 (62.2 – 96.1) 812 (558 – 1,000) 445

20–39 years 50.5 (42.9 – 59.3) 6.19 (4.34 – 8.14) 35.3 (28.1 – 47.1) 821 (468 – 1,160) 282

40–59 years 55.4 (43.6 – 70.3) 7.50 (4.68 – 10.4) 48.2 (38.0 – 62.6) 475 (347 – 1,260) 157

60 years and older 42.1 (31.0 – 57.3) 5.61 (2.89 – 7.89) 40.7 (22.8 – 61.7) 366 (222 – 1,200) 172

Males

Total, 6 years and older 60.8 (52.2 – 70.9) 8.82 (7.42 – 9.78) 48.2 (40.1 – 56.8) 742 (484 – 1,050) 625

6–11 years 76.3 (57.3 – 102) 17.3 (7.01 – 20.6) 60.0 (41.0 – 109) 481 (312 – 1,370) 112

12–19 years 90.0 (69.7 – 116) 16.0 (9.79 – 17.8) 84.7 (53.8 – 129) 590 (408 – 1,270) 228

20–39 years 52.0 (37.9 – 71.3) 7.67 (3.36 – 10.2) 36.0 (27.9 – 48.7) 846 (468 – 1,330) 117

40–59 years 60.4 (39.7 – 92.0) 8.25† (4.94 – 10.0) 47.8 (21.4 – 81.5) 790† (356 – 4,980) 85

60 years and older 41.1 (23.7 – 71.4) 7.55† (1.89 – 9.13) 40.0 (15.3 – 84.1) 329† (154 – 2,020) 83

Females

Total, 6 years and older 57.1 (48.9 – 66.7) 6.73 (5.24 – 8.15) 49.8 (42.3 – 64.2) 556 (418 – 871) 662

6–11 years 80.5 (53.3 – 121) 14.4 (5.79 – 22.1) 65.4 (49.0 – 98.4) 735 (283 – 3,410) 119

12–19 years 84.6 (67.0 – 107) 10.4 (8.24 – 13.6) 71.1 (56.2 – 97.1) 867 (623 – 1,380) 217

20–39 years 48.7 (32.2 – 73.6) 5.71 (3.33 – 8.01) 32.3 (23.7 – 67.2) 594 (295 – 1,790) 165

40–59 years 50.4 (35.6 – 71.2) 5.24† (3.72 – 11.2) 48.4 (35.4 – 84.6) 346† (267 – 484) 72

60 years and older 42.9 (25.7 – 71.5) 5.28† (1.79 – 7.45) 40.1 (18.6 – 73.7) 381† (226 – 2,270) 89

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 381

Table 4.3.a.4. Urinary daidzein: Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 78.4 (67.6 – 90.9) 9.87 (8.52 – 11.6) 72.3 (61.3 – 85.2) 639 (474 – 766) 1,343

6–11 years 102 (80.6 – 129) 11.5 (8.37 – 16.0) 95.8 (70.0 – 129) 927 (487 – 2,170) 207

12–19 years 120 (104 – 139) 17.5 (13.5 – 20.8) 111 (92.3 – 144) 895 (756 – 1,160) 496

20–39 years 68.4 (53.2 – 88.0) 11.3 (8.37 – 13.1) 50.7 (41.3 – 76.5) 601 (408 – 893) 249

40–59 years 77.2 (59.6 – 99.9) 8.40 (6.24 – 11.2) 75.0 (58.8 – 111) 457 (377 – 839) 231

60 years and older 53.5 (37.7 – 75.8) 7.55 (4.20 – 9.29) 46.9 (28.8 – 78.8) 361 (259 – 823) 160

Males

Total, 6 years and older 90.2 (75.1 – 108) 12.1 (8.49 – 14.2) 83.6 (64.7 – 110) 724 (584 – 1,050) 661

6–11 years 101 (70.3 – 145) 11.2† (4.75 – 15.9) 103 (42.5 – 215) 1,050† (534 – 2,140) 99

12–19 years 132 (107 – 164) 19.4 (11.4 – 24.1) 120 (95.6 – 152) 1,140 (766 – 1,980) 258

20–39 years 94.7 (64.5 – 139) 13.2 (7.79 – 16.6) 67.3 (41.4 – 151) 851 (564 – 1,400) 116

40–59 years 78.7 (54.4 – 114) 8.53 (6.17 – 13.3) 83.2 (58.0 – 134) 390 (368 – 701) 114

60 years and older 53.1 (37.3 – 75.7) 8.34† (7.92 – 12.2) 40.3 (27.8 – 70.4) 325† (169 – 1,800) 74

Females

Total, 6 years and older 69.7 (57.7 – 84.2) 9.41 (7.40 – 11.2) 64.7 (54.2 – 77.9) 476 (427 – 675) 682

6–11 years 103 (74.2 – 142) 11.0† (7.50 – 24.0) 85.1 (58.3 – 129) 687† (398 – 7,580) 108

12–19 years 109 (91.8 – 129) 14.3 (9.60 – 22.6) 104 (73.9 – 142) 757 (652 – 1,140) 238

20–39 years 52.7 (37.2 – 74.6) 9.40 (5.61 – 12.1) 43.3 (26.0 – 75.9) 408 (280 – 622) 133

40–59 years 75.9 (51.0 – 113) 7.94 (4.01 – 11.8) 69.9 (47.9 – 109) 462 (369 – 2,070) 117

60 years and older 53.7 (31.4 – 91.7) 6.06† (2.92 – 9.07) 55.3 (22.5 – 106) 368† (257 – 1,170) 86

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.3.a.5. Urinary daidzein: Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic whites in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 63.9 (58.7 – 69.6) 8.36 (6.60 – 9.38) 58.5 (52.0 – 65.3) 571 (479 – 684) 2,108

6–11 years 86.5 (70.6 – 106) 16.0 (11.4 – 20.6) 66.6 (56.0 – 93.6) 643 (450 – 985) 193

12–19 years 91.5 (77.3 – 108) 15.2 (10.6 – 17.3) 76.3 (59.5 – 100) 824 (606 – 977) 378

20–39 years 58.5 (47.8 – 71.7) 6.75 (4.48 – 10.3) 53.0 (44.8 – 66.9) 484 (343 – 753) 494

40–59 years 57.9 (50.4 – 66.5) 7.22 (5.29 – 8.66) 50.6 (41.9 – 65.3) 575 (407 – 893) 448

60 years and older 61.6 (52.9 – 71.8) 8.03 (6.59 – 9.36) 61.2 (49.1 – 78.5) 469 (396 – 662) 595

Males

Total, 6 years and older 70.2 (62.0 – 79.4) 9.34 (7.77 – 12.2) 63.8 (54.1 – 72.9) 680 (509 – 779) 1,035

6–11 years 83.9 (62.4 – 113) 18.4† (7.93 – 21.7) 63.1 (49.4 – 94.1) 651† (271 – 1,180) 99

12–19 years 102 (78.3 – 134) 16.6 (12.7 – 23.1) 80.1 (55.1 – 118) 812 (466 – 1,440) 191

20–39 years 63.4 (48.0 – 83.7) 8.03 (3.27 – 14.2) 59.0 (43.8 – 77.0) 575 (341 – 1,010) 217

40–59 years 66.9 (54.2 – 82.7) 8.29 (6.53 – 9.37) 63.4 (42.1 – 83.3) 670 (409 – 970) 229

60 years and older 64.3 (50.0 – 82.9) 9.18 (6.88 – 12.0) 58.7 (42.2 – 88.7) 591 (416 – 762) 299

Females

Total, 6 years and older 58.3 (52.6 – 64.7) 7.50 (5.79 – 8.68) 53.1 (47.0 – 61.0) 484 (397 – 608) 1,073

6–11 years 89.7 (67.1 – 120) 14.9† (5.43 – 19.0) 89.1 (50.9 – 141) 583† (352 – 7,440) 94

12–19 years 81.0 (66.4 – 98.8) 11.8 (7.34 – 15.8) 73.3 (52.3 – 101) 817 (455 – 970) 187

20–39 years 54.0 (42.7 – 68.5) 6.43 (5.19 – 8.74) 51.1 (38.2 – 64.5) 382 (293 – 683) 277

40–59 years 50.0 (42.1 – 59.4) 5.98 (3.46 – 8.36) 43.5 (32.6 – 53.4) 514 (309 – 843) 219

60 years and older 59.6 (49.4 – 71.8) 7.25 (3.83 – 8.51) 61.4 (49.3 – 83.1) 401 (357 – 656) 296

† Estimate is subject to greater uncertainty due to small cell size. 
382 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.3.b. Urinary daidzein: Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 75.1 (61.9 – 91.1) 6.56 (3.36 – 8.12) 69.8 (58.1 – 82.4) 1,310 (1,030 – 1,550) 2,553

 2001–2002 51.7 (46.6 – 57.5) < LOD 52.3 (49.0 – 57.5) 1,240 (919 – 1,850) 2,794

 2003–2004 66.7 (60.4 – 73.7) 5.71 (4.00 – 6.43) 62.0 (54.1 – 69.7) 1,070 (924 – 1,330) 2,594

 2005–2006 66.5 (59.7 – 74.1) 4.98 (3.70 – 6.58) 58.8 (51.4 – 67.7) 1,180 (1,010 – 1,380) 2,528

Age group

6–11 years

 1999–2000 90.5 (75.1 – 109) 8.59 (1.43 – 13.6) 100 (71.0 – 129) 1,110 (707 – 1,740) 330

 2001–2002 84.9 (71.6 – 101) 11.3 (3.15 – 12.4) 72.1 (56.6 – 96.9) 1,050 (684 – 1,650) 396

 2003–2004 84.9 (71.6 – 101) 13.2 (9.77 – 16.2) 65.6 (56.7 – 92.7) 788 (644 – 1,070) 341

 2005–2006 94.1 (74.3 – 119) 7.73 (6.35 – 10.8) 73.8 (56.1 – 95.1) 1,870 (1,130 – 6,350) 351

12–19 years

 1999–2000 123 (91.4 – 166) 14.7 (7.23 – 17.6) 124 (85.6 – 165) 1,460 (1,100 – 3,300) 753

 2001–2002 69.3 (52.6 – 91.3) 2.63 (< LOD – 6.02) 69.8 (53.2 – 87.5) 1,330 (977 – 2,110) 744

 2003–2004 89.0 (75.2 – 105) 9.05 (6.06 – 9.91) 77.9 (60.1 – 104) 1,190 (927 – 1,970) 729

 2005–2006 94.4 (76.0 – 117) 9.14 (6.14 – 11.0) 76.9 (59.6 – 102) 1,370 (981 – 2,270) 693

20–39 years

 1999–2000 80.6 (64.3 – 101) 7.55 (3.34 – 9.89) 67.1 (55.6 – 82.5) 1,730 (983 – 4,150) 534

 2001–2002 51.5 (42.7 – 62.1) < LOD 50.7 (40.4 – 64.9) 1,200 (763 – 1,930) 604

 2003–2004 59.9 (47.6 – 75.3) 4.82 (3.21 – 6.58) 56.1 (44.9 – 69.0) 1,170 (809 – 1,480) 554

 2005–2006 63.4 (51.7 – 77.6) 4.81 (2.19 – 6.27) 52.3 (44.7 – 68.5) 1,360 (737 – 2,240) 583

40–59 years

 1999–2000 55.4 (39.0 – 78.6) 2.50 (< LOD – 7.77) 56.7 (40.8 – 70.7) 1,060 (801 – 1,520) 420

 2001–2002 50.6 (40.4 – 63.3) < LOD 53.1 (39.3 – 68.2) 1,760 (859 – 3,030) 531

 2003–2004 67.9 (58.3 – 79.2) 5.13 (3.05 – 6.43) 62.2 (46.1 – 78.7) 1,290 (840 – 3,440) 452

 2005–2006 54.9 (47.3 – 63.7) 3.79 (2.99 – 5.86) 50.5 (41.4 – 61.9) 983 (665 – 1,300) 449

60 years and older

 1999–2000 64.6 (53.0 – 78.8) 6.47 (5.61 – 9.10) 61.5 (45.9 – 85.0) 665 (556 – 991) 516

 2001–2002 32.0 (26.2 – 39.0) < LOD 33.8 (28.4 – 40.4) 636 (397 – 1,990) 519

 2003–2004 55.7 (44.4 – 69.9) 4.07 (2.51 – 5.72) 56.5 (43.8 – 76.3) 780 (585 – 1,660) 518

 2005–2006 66.4 (54.6 – 80.8) 4.76 (1.85 – 8.24) 62.5 (43.9 – 89.5) 952 (707 – 1,600) 452

Gender

Males

 1999–2000 88.9 (71.4 – 111) 7.75 (5.85 – 10.4) 80.5 (66.9 – 112) 1,540 (1,020 – 2,240) 1,220

 2001–2002 49.8 (42.8 – 57.9) < LOD 50.7 (46.9 – 55.6) 918 (727 – 1,400) 1,375

 2003–2004 73.8 (63.4 – 85.9) 6.35 (3.20 – 8.53) 65.2 (56.4 – 76.4) 1,200 (1,020 – 1,370) 1,244

 2005–2006 73.9 (65.3 – 83.6) 6.32 (4.02 – 7.91) 66.2 (53.9 – 78.3) 1,180 (1,000 – 1,430) 1,252

Females

 1999–2000 64.1 (52.9 – 77.6) 5.62 (1.86 – 7.80) 57.6 (45.2 – 73.2) 1,210 (652 – 2,010) 1,333

 2001–2002 53.6 (48.1 – 59.8) < LOD 55.4 (49.8 – 62.4) 1,440 (1,190 – 1,990) 1,419

 2003–2004 60.7 (53.6 – 68.8) 4.61 (3.50 – 5.95) 57.4 (49.3 – 67.3) 884 (670 – 1,390) 1,350

 2005–2006 60.1 (52.5 – 68.9) 4.40 (2.99 – 5.94) 52.4 (45.0 – 61.4) 1,140 (843 – 1,480) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 78.9 (59.8 – 104) 6.78 (4.37 – 8.83) 66.1 (48.8 – 90.2) 1,340 (977 – 3,000) 816

 2001–2002 39.2 (28.5 – 54.0) < LOD 39.8 (28.8 – 59.7) 880 (633 – 1,770) 679

 2003–2004 57.4 (50.2 – 65.7) 4.90 (3.74 – 5.99) 45.4 (35.3 – 53.3) 1,380 (954 – 1,720) 653

 2005–2006 60.6 (53.3 – 68.9) 4.35 (2.74 – 5.80) 54.0 (44.1 – 64.5) 1,320 (981 – 1,550) 634

Non-Hispanic Blacks

 1999–2000 91.5 (71.1 – 118) 7.48 (< LOD – 11.2) 102 (84.0 – 131) 1,030 (771 – 1,640) 596

 2001–2002 66.3 (47.7 – 91.9) < LOD 72.9 (52.5 – 96.5) 1,410 (950 – 2,850) 692

 2003–2004 75.5 (56.5 – 101) 7.09 (5.71 – 8.69) 67.6 (51.5 – 89.3) 1,150 (699 – 2,380) 681

 2005–2006 81.3 (71.6 – 92.4) 6.97 (4.66 – 7.57) 76.5 (69.9 – 94.7) 1,200 (878 – 1,960) 662

Non-Hispanic Whites

 1999–2000 74.7 (61.8 – 90.3) 7.25 (3.27 – 8.95) 66.8 (57.0 – 77.4) 1,360 (990 – 1,730) 901

 2001–2002 48.6 (43.8 – 53.9) < LOD 49.8 (45.8 – 53.1) 1,140 (811 – 1,910) 1,211

 2003–2004 65.9 (58.7 – 74.0) 5.10 (3.33 – 6.39) 62.3 (53.0 – 71.3) 1,050 (843 – 1,360) 1,069

 2005–2006 62.0 (54.4 – 70.7) 4.55 (3.17 – 6.33) 54.1 (46.9 – 63.9) 1,030 (884 – 1,310) 1,039

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
5th Percentile 50th Percentile 95th Percentile 

8000 

6000 

4000 

2000 

0 

200 

150 

100 

50 

0 

20 

15 

10 

5 

0 

H H H H H H H 

H 

H H H H H H H H 

H 

H H H H H 

H H H 

H 

H H H 

H H H H H H H 

H 

H 

H H 

H 

H H

H 

H 

H

H H 

H 

H 

H H 

H 

H 

H H 

H H H H 

H 

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H 

H 

H H 

H 

H 

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H 

H 

H 

H H 

H 

H 

H 

H 

H 

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H 

H H 

H 

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H H 

H 

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H H H 

H H 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

Figure 4.3.b. Urinary daidzein: Concentrations by survey cycle 

Selected percentiles in μg/L (95% confidence intervals), National Health and 


Nutrition Examination Survey, 1999–2006
 

4. Isoflavones and Lignans 383
384

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.4.a.1. Urinary daidzein (creatinine corrected): Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 63.7 (60.0 – 67.5) 4.69 (4.17 – 5.11) 6.83 (6.29 – 7.32) 54.6 (50.2 – 58.5) 1,060 (939 – 1,150) 1,890 (1,520 – 2,820) 5,122Age group6–11 years 96.8 (85.1 – 110) 9.11 (7.67 – 11.1) 12.3 (9.30 – 15.7) 72.6 (63.3 – 87.8) 1,630 (1,000 – 2,990) 3,010 (1,860 – 5,360) 692

12–19 years 68.3 (60.0 – 77.7) 5.75 (4.91 – 6.71) 7.91 (6.76 – 9.36) 56.2 (47.3 – 69.0) 910 (755 – 1,210) 1,330 (1,180 – 2,730) 1,422

20–39 years 52.5 (46.6 – 59.3) 3.98 (2.80 – 4.53) 5.88 (4.34 – 6.73) 44.6 (37.9 – 52.2) 878 (685 – 1,100) 1,360 (1,090 – 2,480) 1,137

40–59 years 61.6 (56.1 – 67.8) 4.02 (2.73 – 4.80) 5.99 (4.72 – 7.17) 51.7 (46.0 – 58.2) 1,140 (895 – 2,180) 2,760 (1,510 – 4,990) 901

60 years and older 71.4 (63.3 – 80.5) 5.84 (4.78 – 7.05) 8.24 (7.26 – 9.16) 63.9 (51.3 – 78.0) 1,010 (828 – 1,180) 1,770 (1,120 – 2,940) 970

GenderMales 58.6 (53.5 – 64.1) 4.34 (3.58 – 4.79) 6.32 (5.09 – 7.08) 49.9 (45.5 – 55.2) 924 (812 – 1,100) 1,550 (1,190 – 2,640) 2,496

Females 68.9 (63.4 – 74.9) 5.13 (4.29 – 5.94) 7.44 (6.45 – 8.14) 60.0 (51.0 – 68.9) 1,130 (1,010 – 1,510) 2,100 (1,630 – 3,290) 2,626

Race/ethnicityMexican Americans 53.2 (47.7 – 59.3) 3.88 (2.31 – 4.18) 4.66 (4.10 – 5.41) 47.7 (38.6 – 56.1) 973 (859 – 1,170) 1,750 (1,360 – 2,390) 1,287

Non-Hispanic Blacks 55.0 (48.8 – 62.1) 3.99 (3.43 – 4.57) 5.90 (4.51 – 6.56) 48.0 (39.1 – 59.6) 825 (645 – 1,040) 1,360 (1,020 – 2,320) 1,343

Non-Hispanic Whites 65.1 (60.7 – 69.7) 4.86 (4.30 – 5.83) 7.25 (6.49 – 7.90) 56.0 (50.6 – 60.8) 1,080 (940 – 1,200) 1,890 (1,480 – 3,030) 2,108
6−11 12−19 20−39 40−59 60+ 

0 50 100 150 200 

Urinary daidzein (μg/g creatinine) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

200 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 4.4.a. Urinary daidzein (creatinine corrected): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary daidzein Urinary daidzein (μg/g creatinine) (μg/g creatinine) 0 50 100 150 200 0 50 100 150 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

4. Isoflavones and Lignans 385
386 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.4.a.2. Urinary daidzein (creatinine corrected): Total population

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 63.7 (60.0 – 67.5) 9.68 (8.96 – 10.5) 54.6 (50.2 – 58.5) 522 (463 – 593) 5,122

6–11 years 96.8 (85.1 – 110) 19.0 (14.8 – 23.0) 72.6 (63.3 – 87.8) 697 (580 – 924) 692

12–19 years 68.3 (60.0 – 77.7) 11.5 (9.80 – 12.7) 56.2 (47.3 – 69.0) 522 (419 – 738) 1,422

20–39 years 52.5 (46.6 – 59.3) 8.66 (7.41 – 9.62) 44.6 (37.9 – 52.2) 424 (338 – 501) 1,137

40–59 years 61.6 (56.1 – 67.8) 8.59 (7.78 – 9.25) 51.7 (46.0 – 58.2) 570 (410 – 894) 901

60 years and older 71.4 (63.3 – 80.5) 11.3 (10.1 – 12.0) 63.9 (51.3 – 78.0) 565 (462 – 702) 970

Males

Total, 6 years and older 58.6 (53.5 – 64.1) 8.91 (8.16 – 9.82) 49.9 (45.5 – 55.2) 467 (421 – 543) 2,496

6–11 years 87.5 (73.6 – 104) 15.8 (11.8 – 21.6) 68.2 (54.2 – 82.8) 733 (435 – 1,190) 340

12–19 years 69.8 (57.3 – 85.0) 11.6 (9.54 – 13.5) 53.9 (43.2 – 69.7) 580 (404 – 842) 728

20–39 years 51.3 (44.0 – 59.9) 7.55 (6.03 – 9.50) 43.4 (36.9 – 50.3) 451 (379 – 595) 499

40–59 years 54.2 (46.0 – 63.9) 7.88 (6.08 – 8.73) 47.0 (38.7 – 60.1) 458 (305 – 766) 451

60 years and older 59.3 (49.0 – 71.9) 10.0 (8.24 – 11.5) 51.0 (43.3 – 65.7) 423 (370 – 565) 478

Females

Total, 6 years and older 68.9 (63.4 – 74.9) 10.7 (9.41 – 12.2) 60.0 (51.0 – 68.9) 582 (493 – 702) 2,626

6–11 years 108 (86.1 – 135) 22.3 (14.6 – 27.7) 84.3 (68.0 – 112) 696 (561 – 1,060) 352

12–19 years 66.7 (58.4 – 76.1) 11.4 (9.31 – 13.0) 58.6 (45.9 – 76.2) 514 (379 – 662) 694

20–39 years 53.8 (44.6 – 64.9) 9.21 (7.51 – 10.7) 46.6 (34.7 – 63.9) 349 (237 – 654) 638

40–59 years 69.6 (60.7 – 79.8) 9.63 (7.84 – 12.3) 57.3 (48.8 – 68.7) 699 (459 – 1,130) 450

60 years and older 82.6 (70.8 – 96.4) 12.7 (10.2 – 14.5) 75.0 (58.7 – 92.5) 686 (537 – 965) 492

 

Table 4.4.a.3. Urinary daidzein (creatinine corrected): Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for Mexican Americans in 

the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 53.2 (47.7 – 59.3) 6.93 (6.05 – 7.61) 47.7 (38.6 – 56.1) 527 (431 – 601) 1,287

6–11 years 98.3 (76.7 – 126) 20.2 (16.6 – 23.2) 80.4 (62.1 – 108) 601 (332 – 1,940) 231

12–19 years 67.5 (56.8 – 80.1) 10.8 (7.46 – 13.3) 57.9 (49.4 – 71.5) 492 (380 – 834) 445

20–39 years 40.7 (33.7 – 49.2) 5.59 (4.19 – 7.06) 30.1 (24.2 – 42.4) 499 (290 – 809) 282

40–59 years 50.7 (39.5 – 65.0) 6.01 (4.56 – 7.76) 45.9 (30.2 – 62.8) 537 (275 – 990) 157

60 years and older 52.0 (36.8 – 73.4) 6.95 (5.30 – 8.24) 49.3 (31.5 – 75.6) 344 (253 – 971) 172

Males

Total, 6 years and older 48.0 (40.5 – 56.9) 6.05 (5.04 – 7.07) 40.4 (30.2 – 56.1) 469 (355 – 594) 625

6–11 years 91.5 (66.0 – 127) 20.4 (15.5 – 23.2) 74.0 (50.3 – 130) 429 (313 – 1,510) 112

12–19 years 65.2 (50.4 – 84.4) 12.3 (7.04 – 13.8) 55.2 (37.2 – 91.2) 424 (302 – 861) 228

20–39 years 37.8 (27.7 – 51.5) 4.82 (2.22 – 6.78) 27.8 (20.6 – 44.4) 432 (264 – 899) 117

40–59 years 44.3 (29.3 – 67.1) 5.90† (3.67 – 7.61) 29.8 (16.1 – 73.2) 552† (258 – 1,640) 85

60 years and older 36.7 (21.9 – 61.5) 5.57† (4.50 – 6.89) 35.3 (15.0 – 66.2) 309† (110 – 2,740) 83

Females

Total, 6 years and older 59.6 (50.8 – 69.9) 7.76 (6.39 – 9.44) 53.5 (43.2 – 62.6) 602 (406 – 897) 662

6–11 years 106 (74.4 – 151) 20.1 (13.5 – 27.3) 85.2 (68.2 – 112) 898 (305 – 3,630) 119

12–19 years 69.9 (57.9 – 84.3) 10.1 (6.44 – 13.3) 65.8 (43.1 – 81.9) 736 (477 – 881) 217

20–39 years 44.5 (29.8 – 66.4) 6.66 (4.07 – 8.39) 33.2 (18.7 – 56.2) 569 (207 – 2,670) 165

40–59 years 58.7 (42.8 – 80.4) 6.72† (4.24 – 11.8) 52.7 (40.8 – 75.2) 427† (256 – 924) 72

60 years and older 69.2 (41.2 – 116) 8.25† (3.99 – 13.0) 64.1 (24.7 – 157) 443† (255 – 2,030) 89

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 387

Table 4.4.a.4. Urinary daidzein (creatinine corrected): Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic blacks 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 55.0 (48.8 – 62.1) 8.72 (7.34 – 9.46) 48.0 (39.1 – 59.6) 437 (389 – 538) 1,343

6–11 years 95.6 (75.9 – 121) 13.3 (11.1 – 18.8) 81.9 (67.4 – 108) 1,010 (647 – 1,910) 207

12–19 years 69.0 (60.5 – 78.8) 9.54 (8.52 – 11.6) 66.5 (51.3 – 85.0) 496 (424 – 640) 496

20–39 years 42.4 (34.5 – 52.2) 6.72 (5.68 – 9.60) 28.1 (23.4 – 44.7) 368 (211 – 702) 249

40–59 years 56.1 (45.9 – 68.6) 8.30 (5.49 – 10.0) 48.7 (38.5 – 66.9) 422 (290 – 614) 231

60 years and older 47.7 (35.0 – 64.9) 9.05 (6.31 – 10.7) 42.0 (25.3 – 67.0) 295 (223 – 603) 160

Males

Total, 6 years and older 52.7 (44.7 – 62.0) 7.20 (6.40 – 8.99) 44.4 (32.0 – 63.8) 440 (391 – 532) 661

6–11 years 95.5 (67.1 – 136) 11.2† (8.55 – 13.9) 94.6 (39.1 – 139) 1,210† (646 – 2,090) 99

12–19 years 70.8 (58.3 – 86.0) 9.79 (7.70 – 11.8) 70.0 (53.8 – 88.7) 584 (426 – 910) 258

20–39 years 45.4 (31.9 – 64.8) 6.49 (3.95 – 8.98) 27.2 (20.2 – 77.0) 410 (234 – 1,360) 116

40–59 years 45.0 (31.4 – 64.5) 6.01 (3.03 – 8.96) 42.1 (29.9 – 58.2) 338 (222 – 684) 114

60 years and older 39.0 (26.7 – 56.8) 7.23† (4.44 – 11.3) 25.7 (19.2 – 50.9) 238† (114 – 996) 74

Females

Total, 6 years and older 57.1 (48.2 – 67.6) 9.36 (7.44 – 11.4) 49.4 (39.9 – 66.3) 419 (330 – 593) 682

6–11 years 95.7 (68.8 – 133) 18.3† (6.78 – 23.1) 77.5 (61.2 – 95.9) 758† (307 – 2,820) 108

12–19 years 67.3 (56.6 – 80.0) 9.35 (7.76 – 13.2) 62.7 (46.6 – 85.6) 458 (328 – 895) 238

20–39 years 40.1 (30.2 – 53.3) 7.29 (4.25 – 11.4) 29.9 (23.8 – 42.2) 310 (153 – 668) 133

40–59 years 67.3 (48.1 – 94.2) 9.31 (6.16 – 12.6) 55.0 (35.4 – 90.6) 552 (299 – 922) 117

60 years and older 54.2 (34.6 – 84.9) 9.07† (4.74 – 11.6) 55.5 (26.1 – 79.8) 312† (185 – 1,040) 86

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.4.a.5. Urinary daidzein (creatinine corrected): Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic whites 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 65.1 (60.7 – 69.7) 10.0 (8.80 – 11.4) 56.0 (50.6 – 60.8) 519 (451 – 658) 2,108

6–11 years 93.9 (77.9 – 113) 17.1 (11.9 – 25.8) 70.3 (57.7 – 96.8) 577 (423 – 991) 193

12–19 years 71.8 (60.1 – 85.8) 12.3 (10.4 – 13.6) 57.5 (46.0 – 74.4) 563 (415 – 763) 378

20–39 years 54.0 (45.5 – 64.1) 9.24 (7.14 – 10.8) 46.4 (37.6 – 57.0) 403 (315 – 578) 494

40–59 years 62.2 (55.5 – 69.8) 8.59 (7.54 – 10.0) 52.9 (43.2 – 60.5) 582 (397 – 1,030) 448

60 years and older 73.5 (65.4 – 82.6) 11.4 (10.1 – 12.6) 65.9 (55.2 – 80.0) 548 (459 – 714) 595

Males

Total, 6 years and older 58.7 (52.2 – 65.9) 9.03 (8.12 – 10.5) 49.9 (43.4 – 57.4) 6456 (369 – 638) 1,035

6–11 years 81.3 (60.7 – 109) 15.6† (10.8 – 22.6) 60.2 (45.1 – 95.9) 540† (287 – 2,790) 99

12–19 years 73.1 (55.1 – 97.1) 12.3 (8.32 – 16.7) 54.3 (40.6 – 82.5) 653 (397 – 892) 191

20–39 years 50.3 (39.2 – 64.7) 8.53 (4.63 – 10.7) 41.7 (33.8 – 54.3) 425 (296 – 777) 217

40–59 years 56.0 (46.0 – 68.2) 8.18 (5.53 – 8.99) 46.0 (37.2 – 62.3) 465 (304 – 946) 229

60 years and older 60.0 (48.0 – 74.9) 10.1 (8.07 – 11.6) 54.2 (40.5 – 79.6) 402 (357 – 501) 299

Females

Total, 6 years and older 71.9 (65.4 – 79.1) 11.6 (9.27 – 13.6) 63.3 (53.8 – 73.5) 589 (484 – 818) 1,073

6–11 years 111 (84.1 – 146) 23.8† (12.9 – 33.2) 94.0 (66.0 – 124) 578† (397 – 1,780) 94

12–19 years 70.4 (58.7 – 84.5) 12.2 (7.26 – 16.3) 66.9 (43.9 – 86.4) 520 (372 – 713) 187

20–39 years 57.9 (46.6 – 71.9) 10.1 (7.66 – 13.0) 47.8 (35.8 – 67.5) 385 (237 – 817) 277

40–59 years 69.2 (59.3 – 80.8) 9.16 (7.25 – 13.0) 57.6 (46.3 – 71.7) 894 (410 – 1,310) 219

60 years and older 86.3 (74.3 – 100) 13.4 (10.1 – 15.6) 78.0 (59.8 – 97.1) 656 (519 – 974) 296

† Estimate is subject to greater uncertainty due to small cell size. 
388 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.4.b. Urinary daidzein (creatinine corrected): Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 68.5 (55.9 – 83.9) 6.25 (2.72 – 8.90) 65.1 (52.8 – 80.8) 943 (838 – 1,150) 2,553

 2001–2002 48.5 (43.7 – 54.0) <LOD 48.3 (43.2 – 56.3) 955 (805 – 1,220) 2,794

 2003–2004 62.5 (58.3 – 67.0) 6.82 (5.96 – 7.48) 56.0 (49.9 – 63.5) 1,050 (858 – 1,150) 2,594

 2005–2006 64.8 (58.7 – 71.6) 6.88 (6.01 – 7.54) 52.3 (47.9 – 59.7) 1,070 (924 – 1,380) 2,528

Age group

6–11 years

 1999–2000 92.6 (76.3 – 112) 10.7 (8.22 – 13.1) 93.0 (72.1 – 114) 1,050 (835 – 2,070) 330

 2001–2002 96.4 (79.0 – 118) 13.0 (6.07 – 14.7) 85.9 (60.7 – 126) 934 (712 – 1,370) 396

 2003–2004 90.4 (77.2 – 106) 15.8 (8.36 – 20.2) 72.4 (58.2 – 99.0) 700 (563 – 1,660) 341

 2005–2006 104 (83.1 – 130) 10.8 (8.23 – 13.3) 73.8 (59.5 – 93.5) 2,350 (1,430 – 4,630) 351

12–19 years

 1999–2000 83.1 (58.4 – 118) 7.76 (3.13 – 11.0) 84.8 (54.0 – 123) 991 (725 – 2,680) 753

 2001–2002 53.4 (40.8 – 70.0) 2.77 (<LOD – 4.26) 50.8 (38.8 – 77.4) 1,030 (677 – 1,580) 744

 2003–2004 66.6 (55.7 – 79.6) 8.31 (6.76 – 9.40) 56.3 (45.0 – 74.4) 873 (667 – 1,270) 729

 2005–2006 70.0 (56.9 – 86.2) 7.67 (5.31 – 10.3) 54.7 (42.8 – 74.1) 914 (714 – 1,950) 693

20–39 years

 1999–2000 63.9 (50.7 – 80.6) 5.10 (2.37 – 8.40) 52.8 (41.0 – 81.7) 1,100 (811 – 1,740) 534

 2001–2002 41.6 (35.1 – 49.4) <LOD 43.0 (30.4 – 54.2) 849 (615 – 1,040) 604

 2003–2004 50.5 (43.0 – 59.3) 5.95 (4.11 – 7.11) 42.6 (36.1 – 50.6) 870 (570 – 1,360) 554

 2005–2006 54.6 (45.0 – 66.4) 5.60 (3.60 – 7.48) 47.0 (34.2 – 65.2) 875 (645 – 1,200) 583

40–59 years

 1999–2000 56.2 (39.7 – 79.6) 3.39 (<LOD – 8.27) 50.3 (39.1 – 71.2) 827 (624 – 1,360) 420

 2001–2002 50.2 (40.3 – 62.7) <LOD 53.3 (40.4 – 67.5) 1,220 (848 – 2,140) 531

 2003–2004 65.1 (56.5 – 75.2) 5.51 (4.02 – 7.94) 58.2 (48.9 – 70.6) 1,220 (713 – 4,260) 452

 2005–2006 58.5 (50.8 – 67.4) 6.35 (3.70 – 7.64) 46.1 (40.8 – 56.2) 1,090 (714 – 2,890) 449

60 years and older

 1999–2000 77.6 (63.4 – 94.8) 8.64 (5.52 – 12.0) 82.7 (61.7 – 104) 761 (575 – 996) 516

 2001–2002 37.9 (31.0 – 46.3) <LOD 36.0 (25.9 – 44.2) 726 (502 – 1,780) 519

 2003–2004 65.9 (55.1 – 78.9) 8.01 (6.03 – 9.02) 61.8 (48.0 – 78.2) 973 (653 – 1,870) 518

 2005–2006 77.1 (65.2 – 91.1) 9.10 (6.42 – 11.4) 64.5 (49.7 – 87.6) 1,020 (827 – 1,610) 452

Gender

Males

 1999–2000 69.7 (54.7 – 88.8) 6.40 (1.93 – 9.19) 69.8 (52.1 – 84.2) 1,040 (908 – 1,180) 1,220

 2001–2002 40.5 (34.8 – 47.1) <LOD 41.6 (34.6 – 47.9) 773 (615 – 969) 1,375

 2003–2004 57.7 (49.4 – 67.3) 6.10 (4.73 – 7.35) 48.9 (42.3 – 58.2) 918 (699 – 1,230) 1,244

 2005–2006 59.5 (53.3 – 66.3) 6.42 (4.79 – 7.34) 50.7 (43.2 – 57.6) 926 (814 – 1,170) 1,252

Females

 1999–2000 67.4 (54.8 – 82.9) 5.93 (2.71 – 8.38) 62.1 (51.2 – 80.8) 845 (622 – 1,420) 1,333

 2001–2002 57.6 (50.8 – 65.2) <LOD 59.1 (48.2 – 72.9) 1,170 (949 – 1,430) 1,419

 2003–2004 67.4 (60.8 – 74.9) 7.43 (6.03 – 8.22) 64.9 (54.7 – 73.3) 1,090 (820 – 1,490) 1,350

 2005–2006 70.4 (61.3 – 80.8) 7.47 (5.83 – 8.70) 57.1 (45.2 – 71.2) 1,180 (1,020 – 1,860) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 72.4 (59.1 – 88.9) 6.47 (3.20 – 8.73) 64.0 (46.9 – 90.9) 1,380 (886 – 3,380) 816

 2001–2002 36.9 (27.8 – 49.0) <LOD 37.0 (24.9 – 57.3) 718 (584 – 1,220) 679

 2003–2004 51.8 (45.0 – 59.6) 4.37 (2.94 – 5.89) 47.7 (36.4 – 58.1) 1,120 (870 – 1,380) 653

 2005–2006 54.7 (45.6 – 65.7) 4.79 (3.91 – 5.94) 47.2 (36.0 – 60.6) 917 (662 – 1,130) 634

Non-Hispanic Blacks

 1999–2000 58.7 (46.0 – 74.9) 3.74 (<LOD – 6.58) 67.0 (52.1 – 86.0) 797 (598 – 945) 596

 2001–2002 46.2 (33.2 – 64.3) <LOD 49.5 (35.7 – 69.9) 927 (620 – 1,820) 692

 2003–2004 53.2 (42.4 – 66.7) 5.94 (3.99 – 6.84) 45.3 (30.0 – 72.1) 706 (564 – 1,030) 681

 2005–2006 57.0 (50.3 – 64.5) 5.39 (4.33 – 6.69) 48.5 (42.1 – 59.5) 902 (643 – 1,350) 662

Non-Hispanic Whites

 1999–2000 73.6 (60.7 – 89.2) 8.09 (3.07 – 10.9) 67.9 (57.2 – 81.4) 917 (794 – 1,390) 901

 2001–2002 48.0 (43.5 – 53.0) <LOD 47.0 (42.8 – 55.4) 954 (838 – 1,220) 1,211

 2003–2004 64.9 (59.9 – 70.4) 7.20 (6.28 – 8.08) 58.2 (50.9 – 66.8) 1,090 (818 – 1,320) 1,069

 2005–2006 65.2 (57.9 – 73.3) 7.34 (5.54 – 8.21) 52.6 (46.5 – 60.6) 1,070 (896 – 1,460) 1,039

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
5000 

4000 

3000 

5th Percentile 50th Percentile 95th Percentile 2000 

1000 

0 

150 

100 

50 

0 

25 

20 

15 

10 

5 

0 

H H H H H H 

H 

H 

H H H H H H H H H 

H H H H 

H H H 

H 

H 

H 

H H H 

H 

H H H H H 

H 

H 

H H 

H 

H 

H H 

H 

H H H H 

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H H 

H H 

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H 

H H 

H 

H H H 

H 

H 

H H 

H H H 

H

H 

H 

H 

H H H 

H H H H H H H 

H H 

H 

H H 

H H 

H H H 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

Figure 4.4.b. Urinary daidzein (creatinine corrected): 

Concentrations by survey cycle 

Selected percentiles in μg/g creatinine (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006

4. Isoflavones and Lignans 389
390

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.5.a.1. Urinary equol: Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 8.21 (7.61 – 8.85) .499 (.468 – .593) .953 (.754 – 1.08) 8.33 (7.59 – 9.06) 64.8 (56.0 – 80.8) 205 (138 – 329) 5,117

Age group6–11 years 12.8 (11.1 – 14.8) 1.10 (.794 – 1.49) 1.95 (1.25 – 2.17) 13.2 (10.8 – 16.0) 84.9 (60.3 – 131) 140 (106 – 311) 692

12–19 years 11.1 (10.0 – 12.2) .998 (.671 – 1.27) 1.62 (1.28 – 1.88) 10.8 (9.61 – 11.7) 72.2 (53.8 – 114) 148 (114 – 287) 1,422

20–39 years 8.39 (7.41 – 9.50) .594 (.357 – .766) .897 (.690 – 1.20) 8.80 (7.71 – 9.78) 71.7 (50.4 – 132) 200 (117 – 563) 1,137

40–59 years 6.85 (6.06 – 7.75) .385 (< LOD – .491) .559 (.468 – .964) 6.37 (5.36 – 7.63) 56.2 (43.6 – 146) 314 (117 – 1,220) 897

60 years and older 6.96 (6.06 – 8.00) .393 (< LOD – .621) .884 (.591 – 1.02) 7.07 (6.06 – 8.03) 51.4 (38.7 – 86.4) 150 (72.5 – 372) 969

GenderMales 8.85 (8.10 – 9.66) .710 (.496 – .967) 1.18 (.986 – 1.28) 9.07 (8.18 – 10.0) 67.2 (55.6 – 93.0) 147 (117 – 246) 2,492

Females 7.65 (6.95 – 8.42) .450 (.300 – .502) .715 (.575 – .892) 7.49 (6.81 – 8.27) 64.4 (51.6 – 89.1) 257 (158 – 541) 2,625

Race/ethnicityMexican Americans 6.06 (5.46 – 6.72) .489 (< LOD – .602) .793 (.585 – .992) 5.87 (5.28 – 6.69) 46.2 (38.7 – 73.5) 107 (70.7 – 201) 1,287

Non-Hispanic Blacks 7.13 (6.35 – 8.01) .570 (.343 – .694) .846 (.693 – 1.02) 6.82 (6.08 – 8.20) 48.5 (40.2 – 61.3) 78.3 (67.8 – 117) 1,340

Non-Hispanic Whites 8.78 (7.99 – 9.65) .499 (.471 – .580) .994 (.725 – 1.20) 9.15 (8.27 – 9.99) 69.8 (56.4 – 96.8) 242 (146 – 504) 2,106

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
6−11 12−19 20−39 40−59 60+ 

0 10 20 3 

Urinary equol (μg/L) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

30 

Non−Hispanic Blacks Non−Hispanic Whites 

0 

Figure 4.5.a. Urinary equol: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary equol Urinary equol (μg/L) (μg/L) 0 10 20 30 0 10 20 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

4. Isoflavones and Lignans 391
392 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.5.a.2. Urinary equol: Total population

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 

years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 8.21 (7.61 – 8.85) 1.49 (1.30 – 1.60) 8.33 (7.59 – 9.06) 36.7 (33.8 – 39.7) 5,117

6–11 years 12.8 (11.1 – 14.8) 2.75 (2.10 – 3.50) 13.2 (10.8 – 16.0) 45.5 (41.5 – 65.3) 692

12–19 years 11.1 (10.0 – 12.2) 2.61 (2.29 – 2.90) 10.8 (9.61 – 11.7) 42.8 (38.6 – 47.0) 1,422

20–39 years 8.39 (7.41 – 9.50) 1.50 (1.20 – 1.80) 8.80 (7.71 – 9.78) 36.5 (30.8 – 42.8) 1,137

40–59 years 6.85 (6.06 – 7.75) 1.28 (1.07 – 1.41) 6.37 (5.36 – 7.63) 33.3 (29.7 – 37.5) 897

60 years and older 6.96 (6.06 – 8.00) 1.30 (1.09 – 1.51) 7.07 (6.06 – 8.03) 32.0 (24.4 – 39.1) 969

Males

Total, 6 years and older 8.85 (8.10 – 9.66) 1.60 (1.38 – 1.99) 9.07 (8.18 – 10.0) 38.6 (34.4 – 42.9) 2,492

6–11 years 15.0 (12.6 – 17.8) 3.79 (2.20 – 5.37) 16.4 (13.2 – 19.2) 50.1 (43.4 – 74.2) 340

12–19 years 12.0 (10.5 – 13.7) 2.67 (2.24 – 3.29) 11.7 (10.6 – 12.7) 44.8 (36.9 – 69.0) 728

20–39 years 8.42 (7.10 – 9.99) 1.47 (1.03 – 1.83) 8.70 (7.21 – 10.0) 41.3 (31.1 – 52.6) 499

40–59 years 7.16 (6.07 – 8.44) 1.42 (1.20 – 1.79) 7.44 (5.69 – 8.91) 30.0 (24.3 – 37.4) 447

60 years and older 8.22 (6.78 – 9.98) 1.50 (1.23 – 1.83) 8.44 (7.09 – 10.1) 36.2 (27.5 – 46.9) 478

Females

Total, 6 years and older 7.65 (6.95 – 8.42) 1.30 (1.19 – 1.50) 7.49 (6.81 – 8.27) 34.8 (32.1 – 38.7) 2,625

6–11 years 10.9 (9.07 – 13.1) 2.43 (1.59 – 2.80) 10.1 (9.16 – 12.5) 43.5 (35.0 – 69.5) 352

12–19 years 10.1 (8.93 – 11.5) 2.49 (1.87 – 2.83) 9.39 (8.03 – 11.4) 40.4 (34.8 – 47.1) 694

20–39 years 8.36 (7.09 – 9.86) 1.50 (1.06 – 1.97) 9.07 (7.09 – 10.6) 32.2 (28.2 – 40.7) 638

40–59 years 6.58 (5.45 – 7.95) .939 (.529 – 1.29) 5.69 (4.68 – 6.95) 34.5 (30.9 – 45.9) 450

60 years and older 6.10 (5.03 – 7.39) 1.18 (.974 – 1.40) 5.80 (5.20 – 7.32) 26.4 (19.2 – 40.6) 491

 

Table 4.5.a.3. Urinary equol: Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/L) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 6.06 (5.46 – 6.72) 1.27 (1.01 – 1.49) 5.87 (5.28 – 6.69) 25.8 (20.9 – 35.4) 1,287

6–11 years 9.49 (7.78 – 11.6) 1.60 (1.05 – 2.47) 9.20 (6.88 – 11.7) 45.5 (37.6 – 85.8) 231

12–19 years 8.07 (7.04 – 9.24) 1.60 (1.44 – 2.01) 7.08 (6.25 – 8.19) 35.7 (27.8 – 49.2) 445

20–39 years 5.71 (4.97 – 6.56) 1.27 (.967 – 1.51) 5.59 (4.49 – 6.42) 21.9 (17.9 – 39.2) 282

40–59 years 4.63 (3.73 – 5.75) 1.08 (< LOD – 1.48) 4.99 (3.92 – 5.86) 19.0 (14.0 – 25.0) 157

60 years and older 4.10 (3.21 – 5.23) .631 (.379 – .946) 4.73 (3.19 – 6.60) 16.6 (10.8 – 27.3) 172

Males

Total, 6 years and older 5.92 (5.25 – 6.68) 1.29 (1.04 – 1.57) 5.69 (4.89 – 6.81) 24.6 (19.8 – 32.9) 625

6–11 years 10.1 (7.14 – 14.3) 2.17 (.735 – 3.86) 9.71 (6.15 – 14.4) 40.8 (26.9 – 88.4) 112

12–19 years 8.75 (7.28 – 10.5) 1.83 (1.35 – 2.32) 7.71 (6.15 – 9.42) 41.1 (28.6 – 61.8) 228

20–39 years 4.81 (3.96 – 5.86) 1.15 (.685 – 1.41) 4.55 (3.70 – 6.03) 18.0 (12.6 – 40.6) 117

40–59 years 5.22 (4.05 – 6.72) 1.18† (.707 – 1.98) 5.27 (4.28 – 6.94) 19.5† (12.5 – 31.6) 85

60 years and older 4.36 (3.01 – 6.31) .600† (< LOD – 1.47) 4.99 (3.05 – 6.89) 17.3† (9.44 – 65.3) 83

Females

Total, 6 years and older 6.21 (5.35 – 7.22) 1.20 (.793 – 1.51) 6.18 (5.15 – 7.09) 28.0 (20.7 – 39.6) 662

6–11 years 8.89 (6.62 – 11.9) 1.47 (.569 – 2.34) 8.44 (5.75 – 11.4) 57.0 (37.3 – 202) 119

12–19 years 7.41 (6.32 – 8.69) 1.50 (.916 – 2.21) 6.81 (5.51 – 8.03) 28.4 (19.3 – 52.0) 217

20–39 years 6.99 (5.35 – 9.13) 1.37 (.689 – 1.85) 6.79 (4.70 – 9.31) 35.2 (19.6 – 66.9) 165

40–59 years 4.07 (2.94 – 5.64) .861† (< LOD – 1.36) 3.89 (2.93 – 5.72) 18.3† (14.0 – 34.4) 72

60 years and older 3.90 (2.50 – 6.08) .671† (< LOD – 1.12) 4.41 (2.15 – 7.53) 14.8† (9.40 – 80.2) 89

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 393

Table 4.5.a.4. Urinary equol: Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 7.13 (6.35 – 8.01) 1.49 (1.28 – 1.70) 6.82 (6.08 – 8.20) 31.3 (27.1 – 36.6) 1,340

6–11 years 11.9 (9.99 – 14.2) 3.00 (2.09 – 3.59) 10.8 (8.53 – 14.0) 54.2 (40.6 – 79.7) 207

12–19 years 9.86 (8.44 – 11.5) 2.40 (1.99 – 2.78) 8.98 (7.83 – 10.3) 42.5 (35.2 – 61.4) 496

20–39 years 7.03 (5.93 – 8.34) 1.50 (1.01 – 2.10) 6.94 (5.91 – 9.58) 24.6 (21.6 – 32.3) 249

40–59 years 5.91 (4.67 – 7.49) 1.19 (.705 – 1.60) 5.49 (4.44 – 7.21) 33.4 (21.8 – 45.8) 228

60 years and older 4.79 (3.89 – 5.91) .852 (.685 – 1.10) 5.17 (4.14 – 6.24) 21.8 (17.1 – 30.7) 160

Males

Total, 6 years and older 7.47 (6.72 – 8.30) 1.57 (1.36 – 1.74) 6.78 (5.94 – 8.18) 31.5 (27.0 – 39.4) 658

6–11 years 13.3 (10.4 – 17.1) 3.43† (1.29 – 4.53) 12.7 (9.66 – 14.9) 71.1† (35.1 – 125) 99

12–19 years 10.8 (8.60 – 13.5) 2.73 (1.99 – 3.07) 9.98 (7.56 – 12.6) 40.1 (32.6 – 70.0) 258

20–39 years 7.77 (6.53 – 9.24) 1.46 (1.21 – 2.10) 6.65 (5.38 – 9.46) 27.4 (23.1 – 45.5) 116

40–59 years 5.52 (4.14 – 7.35) 1.46† (1.11 – 1.67) 5.13 (4.01 – 7.66) 24.5† (13.5 – 51.5) 111

60 years and older 4.15 (3.25 – 5.29) .758† (< LOD – 1.27) 4.28 (3.25 – 5.82) 21.7† (10.8 – 66.2) 74

Females

Total, 6 years and older 6.87 (5.87 – 8.04) 1.25 (.765 – 1.80) 6.86 (5.92 – 8.46) 30.3 (25.2 – 37.5) 682

6–11 years 10.6 (7.95 – 14.2) 2.52† (1.45 – 3.58) 9.24 (6.86 – 12.6) 47.6† (30.5 – 124) 108

12–19 years 9.01 (7.47 – 10.9) 2.08 (1.31 – 2.78) 8.50 (7.01 – 9.53) 43.6 (31.4 – 71.3) 238

20–39 years 6.49 (5.06 – 8.33) 1.50 (.605 – 2.40) 7.06 (4.83 – 10.1) 22.2 (17.7 – 30.1) 133

40–59 years 6.25 (4.47 – 8.74) .702 (.318 – 1.88) 5.84 (4.69 – 8.20) 37.0 (24.8 – 63.0) 117

60 years and older 5.26 (4.08 – 6.78) .872† (.723 – 1.03) 5.43 (3.80 – 8.00) 21.8† (17.4 – 37.7) 86

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.5.a.5. Urinary equol: Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic whites in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 8.78 (7.99 – 9.65) 1.54 (1.30 – 1.80) 9.15 (8.27 – 9.99) 38.2 (34.4 – 43.0) 2,106

6–11 years 14.7 (11.9 – 18.1) 3.40 (2.09 – 5.41) 16.3 (12.7 – 18.8) 44.9 (38.1 – 78.1) 193

12–19 years 12.1 (10.6 – 13.8) 3.09 (2.50 – 3.61) 11.9 (10.6 – 13.6) 42.0 (36.7 – 46.5) 378

20–39 years 9.62 (8.11 – 11.4) 1.57 (1.13 – 2.04) 10.0 (8.77 – 11.7) 42.8 (32.6 – 57.5) 494

40–59 years 7.04 (6.11 – 8.12) 1.29 (.848 – 1.49) 6.87 (5.37 – 8.81) 33.8 (30.8 – 37.4) 447

60 years and older 7.65 (6.47 – 9.04) 1.46 (1.17 – 1.88) 7.66 (6.29 – 8.72) 33.6 (25.9 – 47.8) 594

Males

Total, 6 years and older 9.68 (8.71 – 10.8) 1.71 (1.40 – 2.10) 10.0 (8.94 – 11.1) 40.1 (36.0 – 45.2) 1,034

6–11 years 17.5 (13.8 – 22.2) 5.59† (2.11 – 6.02) 17.5 (13.5 – 24.4) 44.9† (39.9 – 115) 99

12–19 years 13.4 (11.3 – 16.0) 3.28 (1.89 – 4.54) 12.2 (11.3 – 15.4) 45.0 (36.6 – 79.1) 191

20–39 years 9.63 (7.72 – 12.0) 1.54 (1.00 – 2.07) 10.0 (8.68 – 11.5) 44.3 (32.4 – 82.8) 217

40–59 years 7.61 (6.19 – 9.35) 1.41 (1.08 – 1.91) 7.93 (5.97 – 9.71) 31.4 (26.6 – 42.6) 228

60 years and older 9.32 (7.43 – 11.7) 1.73 (1.27 – 2.50) 9.42 (7.36 – 12.1) 37.6 (30.7 – 55.2) 299

Females

Total, 6 years and older 7.98 (7.02 – 9.06) 1.45 (1.20 – 1.60) 7.86 (6.93 – 9.16) 35.6 (31.7 – 42.8) 1,072

6–11 years 12.0 (8.61 – 16.7) 2.61† (.948 – 3.85) 12.3 (9.15 – 17.3) 43.2† (27.4 – 91.7) 94

12–19 years 10.8 (8.95 – 13.0) 2.76 (1.92 – 3.64) 11.1 (8.16 – 13.8) 39.9 (32.0 – 45.3) 187

20–39 years 9.60 (7.63 – 12.1) 1.66 (.954 – 2.27) 10.3 (7.50 – 12.8) 37.3 (29.2 – 72.9) 277

40–59 years 6.52 (5.18 – 8.20) .967 (.492 – 1.32) 6.18 (4.63 – 7.52) 33.9 (30.9 – 47.3) 219

60 years and older 6.54 (5.19 – 8.25) 1.27 (.956 – 1.58) 6.08 (5.27 – 8.01) 29.4 (18.6 – 55.9) 295

† Estimate is subject to greater uncertainty due to small cell size. 
394 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.5.b. Urinary equol: Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 8.37 (7.21 – 9.72) < LOD 8.00 (6.29 – 9.82) 53.7 (41.6 – 79.6) 2,182

 2001–2002 9.17 (7.76 – 10.8) < LOD 8.94 (7.36 – 10.4) 73.5 (56.4 – 95.8) 2,794

 2003–2004 8.02 (7.07 – 9.10) .934 (.655 – 1.11) 7.98 (6.77 – 9.36) 64.8 (47.0 – 100) 2,590

 2005–2006 8.40 (7.63 – 9.24) .878 (.698 – 1.08) 8.60 (7.91 – 9.17) 64.5 (56.9 – 80.5) 2,527

Age group

6–11 years

 1999–2000 10.4 (7.65 – 14.3) < LOD 11.5 (5.76 – 18.5) 55.4 (32.5 – 310) 272

 2001–2002 12.2 (10.2 – 14.6) < LOD 13.7 (11.1 – 16.1) 84.5 (53.6 – 214) 396

 2003–2004 12.4 (9.71 – 15.8) 1.92 (1.00 – 2.31) 12.0 (8.45 – 17.6) 85.4 (49.1 – 251) 341

 2005–2006 13.3 (11.3 – 15.7) 1.90 (1.02 – 2.49) 13.4 (12.1 – 16.6) 70.3 (54.3 – 228) 351

12–19 years

 1999–2000 10.9 (8.64 – 13.8) < LOD 10.7 (8.57 – 13.3) 71.6 (51.1 – 235) 657

 2001–2002 10.2 (8.50 – 12.1) < LOD 10.4 (8.27 – 12.5) 68.9 (48.1 – 106) 744

 2003–2004 10.6 (8.96 – 12.4) 1.64 (1.05 – 2.11) 10.5 (8.73 – 12.1) 61.8 (46.0 – 113) 729

 2005–2006 11.6 (10.3 – 13.0) 1.49 (1.19 – 2.04) 11.2 (9.48 – 12.3) 81.6 (54.9 – 148) 693

20–39 years

 1999–2000 7.66 (6.63 – 8.86) < LOD 7.55 (5.49 – 9.38) 38.1 (35.6 – 69.4) 439

 2001–2002 9.35 (7.40 – 11.8) < LOD 9.25 (6.95 – 11.3) 67.0 (49.7 – 111) 604

 2003–2004 8.81 (7.29 – 10.6) .980 (.509 – 1.31) 9.11 (7.18 – 10.8) 99.6 (44.4 – 221) 554

 2005–2006 8.00 (6.71 – 9.54) .820 (.587 – 1.18) 8.60 (7.42 – 9.73) 57.1 (45.0 – 95.1) 583

40–59 years

 1999–2000 7.80 (6.17 – 9.84) < LOD 7.28 (4.97 – 9.09) 53.7 (34.0 – 3,160) 378

 2001–2002 8.92 (7.27 – 10.9) < LOD 8.12 (6.43 – 10.1) 102 (44.7 – 312) 531

 2003–2004 6.65 (5.61 – 7.87) .613 (.372 – 1.04) 6.09 (4.66 – 8.60) 51.6 (38.0 – 140) 448

 2005–2006 7.05 (5.83 – 8.54) .542 (.325 – 1.07) 6.76 (5.33 – 8.36) 63.8 (38.6 – 542) 449

60 years and older

 1999–2000 8.04 (6.93 – 9.33) < LOD 7.33 (5.55 – 9.70) 54.8 (35.9 – 237) 436

 2001–2002 7.18 (5.83 – 8.85) < LOD 5.68 (3.76 – 8.16) 51.0 (41.8 – 113) 519

 2003–2004 6.16 (4.93 – 7.68) .754 (< LOD – 1.02) 5.88 (4.99 – 7.75) 39.6 (32.2 – 176) 518

 2005–2006 7.84 (6.60 – 9.31) .940 (.599 – 1.16) 7.80 (6.29 – 8.95) 55.5 (42.4 – 326) 451

Gender

Males

 1999–2000 9.15 (7.37 – 11.4) < LOD 8.44 (6.38 – 11.2) 68.8 (45.0 – 170) 1,042

 2001–2002 9.41 (7.99 – 11.1) < LOD 9.14 (7.65 – 10.6) 61.4 (52.6 – 87.6) 1,375

 2003–2004 8.56 (7.54 – 9.72) 1.07 (.861 – 1.26) 8.70 (7.18 – 10.2) 72.3 (50.8 – 112) 1,240

 2005–2006 9.13 (7.99 – 10.4) 1.19 (.892 – 1.29) 9.40 (8.15 – 10.6) 61.7 (53.1 – 94.2) 1,252

Females

 1999–2000 7.70 (6.79 – 8.74) < LOD 7.56 (5.92 – 8.98) 48.2 (37.6 – 70.9) 1,140

 2001–2002 8.94 (7.38 – 10.8) < LOD 8.54 (6.72 – 10.6) 79.3 (58.9 – 130) 1,419

 2003–2004 7.55 (6.44 – 8.84) .792 (.480 – 1.02) 7.29 (6.12 – 8.96) 60.2 (43.8 – 145) 1,350

 2005–2006 7.75 (6.85 – 8.78) .684 (.486 – .877) 7.56 (6.93 – 8.36) 69.0 (54.8 – 119) 1,275

Race/ethnicity

Mexican Americans

 1999–2000 5.24 (4.77 – 5.75) < LOD 4.51 (3.75 – 5.25) 30.3 (22.6 – 62.5) 726

 2001–2002 7.22 (6.04 – 8.62) < LOD 6.49 (4.52 – 8.98) 42.1 (40.1 – 48.7) 679

 2003–2004 6.08 (5.08 – 7.28) .927 (.625 – 1.18) 5.64 (4.65 – 6.77) 43.5 (36.2 – 108) 653

 2005–2006 6.04 (5.31 – 6.87) .663 (.440 – .961) 6.12 (5.32 – 7.09) 47.6 (36.7 – 83.0) 634

Non-Hispanic Blacks

 1999–2000 6.67 (5.16 – 8.63) < LOD 6.12 (3.87 – 9.88) 36.5 (30.0 – 52.0) 504

 2001–2002 7.11 (6.01 – 8.42) < LOD 6.00 (4.62 – 7.48) 45.2 (40.7 – 99.6) 692

 2003–2004 7.32 (6.13 – 8.73) .753 (.505 – 1.11) 7.85 (6.09 – 9.58) 46.9 (39.8 – 62.3) 678

 2005–2006 6.96 (5.89 – 8.22) .868 (.686 – 1.05) 6.37 (5.48 – 7.85) 48.6 (39.2 – 64.9) 662

Non-Hispanic Whites

 1999–2000 9.38 (7.94 – 11.1) < LOD 8.98 (6.99 – 11.8) 56.1 (45.4 – 95.5) 744

 2001–2002 9.89 (7.90 – 12.4) < LOD 9.93 (7.31 – 12.5) 74.1 (55.1 – 108) 1,211

 2003–2004 8.51 (7.22 – 10.0) .996 (.618 – 1.19) 8.72 (6.95 – 10.3) 72.9 (46.8 – 120) 1,068

 2005–2006 9.05 (8.08 – 10.1) .965 (.606 – 1.27) 9.48 (8.56 – 10.3) 68.9 (56.9 – 105) 1,038

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
5th Percentile 50th Percentile 95th Percentile 

400 

300 

200 

100 

0 

20 

15 

10 

5 

0 

2.5 

2.0 

1.5 

1.0 

0.5 

0.0 

H 

H H H H 

H H H H H H 

H 

H 

H H H H H H H H 

H 

H H 

H H H H H H H H H 

H H H 

H 

H 

H H 

H 

H 

H 

H 

H H H H 

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H 

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H H 

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H H H H 

H 

H 

H

H 

H H 

H H 

H H 

H 

H 

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H 

H 

H 

H 

H 

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H 

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99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

Figure 4.5.b. Urinary equol: Concentrations by survey cycle 

Selected percentiles in μg/L (95% confidence intervals), National Health and 


Nutrition Examination Survey, 1999–2006
 

4. Isoflavones and Lignans 395
396

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.6.a.1. Urinary equol (creatinine corrected): Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 7.85 (7.31 – 8.43) .724 (.600 – .799) 1.05 (.898 – 1.18) 7.64 (7.10 – 8.15) 58.1 (48.3 – 78.3) 219 (129 – 356) 5,117

Age group6–11 years 13.9 (12.4 – 15.6) 1.45 (1.00 – 2.26) 2.51 (1.79 – 3.00) 14.4 (12.3 – 16.0) 92.0 (59.9 – 129) 136 (117 – 270) 692

12–19 years 8.24 (7.40 – 9.19) .948 (.501 – 1.34) 1.49 (1.13 – 1.81) 8.04 (7.17 – 8.69) 48.2 (38.2 – 75.3) 118 (80.6 – 216) 1,422

20–39 years 7.15 (6.38 – 8.02) .675 (.540 – .776) .901 (.763 – 1.06) 7.06 (6.25 – 7.86) 63.7 (40.1 – 115) 210 (118 – 392) 1,137

40–59 years 6.95 (6.07 – 7.96) .538 (< LOD – .693) .792 (.629 – 1.08) 6.57 (5.54 – 7.54) 66.0 (35.1 – 245) 421 (110 – 1,130) 897

60 years and older 8.16 (7.32 – 9.08) .889 (< LOD – 1.11) 1.33 (1.11 – 1.52) 8.13 (7.12 – 8.80) 45.3 (33.8 – 99.4) 140 (63.1 – 436) 969

GenderMales 7.02 (6.46 – 7.64) .634 (.462 – .769) .942 (.768 – 1.10) 6.84 (6.27 – 7.53) 51.8 (44.0 – 67.2) 129 (106 – 237) 2,492

Females 8.72 (8.02 – 9.49) .787 (.705 – .890) 1.18 (.964 – 1.39) 8.36 (7.88 – 8.98) 70.0 (48.3 – 104) 356 (169 – 692) 2,625

Race/ethnicityMexican Americans 5.46 (4.94 – 6.04) .615 (< LOD – .690) .867 (.674 – 1.04) 4.84 (4.34 – 5.48) 37.9 (33.4 – 69.8) 129 (83.3 – 192) 1,287

Non-Hispanic Blacks 5.02 (4.48 – 5.62) .533 (.403 – .669) .766 (.655 – .917) 4.88 (4.40 – 5.59) 30.5 (26.1 – 42.2) 64.8 (42.5 – 96.6) 1,340

Non-Hispanic Whites 8.94 (8.26 – 9.67) .792 (.621 – .977) 1.18 (1.07 – 1.38) 8.65 (7.95 – 9.50) 69.4 (48.3 – 107) 267 (155 – 502) 2,106

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
6−11 12−19 20−39 40−59 60+ 

0 5 10 15 20 25 

Urinary equol (μg/g creatinine) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

25 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 4.6.a. Urinary equol (creatinine corrected): Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary equol Urinary equol (μg/g creatinine) (μg/g creatinine) 0 5 10 15 20 25 0 5 10 15 20 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

4. Isoflavones and Lignans 397
398 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.6.a.2. Urinary equol (creatinine corrected): Total population

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 7.85 (7.31 – 8.43) 1.72 (1.54 – 1.90) 7.64 (7.10 – 8.15) 30.7 (28.8 – 32.6) 5,117

6–11 years 13.9 (12.4 – 15.6) 3.64 (2.88 – 4.34) 14.4 (12.3 – 16.0) 44.9 (40.5 – 57.6) 692

12–19 years 8.24 (7.40 – 9.19) 2.09 (1.87 – 2.39) 8.04 (7.17 – 8.69) 31.3 (26.0 – 35.0) 1,422

20–39 years 7.15 (6.38 – 8.02) 1.45 (1.17 – 1.73) 7.06 (6.25 – 7.86) 29.5 (23.7 – 34.6) 1,137

40–59 years 6.95 (6.07 – 7.96) 1.40 (1.14 – 1.60) 6.57 (5.54 – 7.54) 25.6 (21.3 – 34.3) 897

60 years and older 8.16 (7.32 – 9.08) 2.14 (1.86 – 2.43) 8.13 (7.12 – 8.80) 27.1 (21.6 – 34.0) 969

Males

Total, 6 years and older 7.02 (6.46 – 7.64) 1.48 (1.28 – 1.76) 6.84 (6.27 – 7.53) 28.8 (25.7 – 31.7) 2,492

6–11 years 15.0 (12.9 – 17.5) 3.84 (3.12 – 4.90) 16.1 (14.7 – 19.0) 45.4 (37.2 – 90.4) 340

12–19 years 8.15 (7.01 – 9.47) 1.92 (1.72 – 2.25) 8.15 (6.93 – 9.51) 31.3 (25.8 – 47.4) 728

20–39 years 6.14 (5.31 – 7.10) 1.26 (.981 – 1.47) 5.83 (4.99 – 6.67) 25.2 (20.0 – 34.6) 499

40–59 years 5.69 (4.78 – 6.77) 1.18 (.790 – 1.58) 5.53 (4.55 – 6.67) 21.8 (15.9 – 33.7) 447

60 years and older 7.58 (6.47 – 8.88) 1.87 (1.37 – 2.25) 7.28 (6.43 – 8.67) 28.8 (20.8 – 34.1) 478

Females

Total, 6 years and older 8.72 (8.02 – 9.49) 1.95 (1.67 – 2.16) 8.36 (7.88 – 8.98) 32.3 (30.1 – 34.9) 2,625

6–11 years 12.8 (11.0 – 15.0) 3.24 (2.47 – 4.43) 12.8 (10.1 – 14.7) 44.8 (39.8 – 57.7) 352

12–19 years 8.35 (7.44 – 9.37) 2.33 (1.89 – 2.72) 7.94 (7.03 – 8.71) 30.5 (22.8 – 37.1) 694

20–39 years 8.32 (7.03 – 9.84) 1.87 (1.20 – 2.15) 8.08 (7.13 – 9.13) 32.2 (25.0 – 38.8) 638

40–59 years 8.39 (7.05 – 9.98) 1.51 (1.19 – 1.86) 7.92 (6.51 – 9.40) 31.4 (24.1 – 43.1) 450

60 years and older 8.65 (7.36 – 10.2) 2.41 (2.00 – 2.83) 8.44 (7.65 – 9.39) 26.8 (20.4 – 39.8) 491

Table 4.6.a.3. Urinary equol (creatinine corrected): Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for Mexican Americans in 

the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 5.46 (4.94 – 6.04) 1.29 (1.14 – 1.43) 4.84 (4.34 – 5.48) 22.4 (19.7 – 27.6) 1,287

6–11 years 11.9 (10.4 – 13.7) 2.42 (1.84 – 4.06) 10.9 (8.91 – 13.8) 58.9 (30.4 – 121) 231

12–19 years 6.23 (5.49 – 7.07) 1.62 (1.35 – 1.73) 5.57 (4.69 – 6.09) 25.3 (19.7 – 34.5) 445

20–39 years 4.61 (3.91 – 5.42) 1.12 (.736 – 1.37) 4.10 (3.26 – 4.90) 19.6 (15.2 – 31.0) 282

40–59 years 4.24 (3.57 – 5.04) 1.23 (< LOD – 1.43) 4.11 (3.40 – 4.80) 14.0 (11.8 – 27.0) 157

60 years and older 5.06 (4.22 – 6.06) 1.46 (.752 – 1.97) 4.82 (3.84 – 6.04) 19.0 (10.5 – 61.0) 172

Males

Total, 6 years and older 4.67 (4.08 – 5.35) 1.16 (.883 – 1.34) 4.23 (3.78 – 5.04) 18.9 (16.3 – 21.2) 625

6–11 years 12.1 (9.02 – 16.2) 3.55 (1.73 – 4.93) 10.6 (8.24 – 16.2) 35.9 (27.4 – 108) 112

12–19 years 6.33 (5.37 – 7.48) 1.60 (1.35 – 1.82) 5.58 (4.35 – 6.84) 27.5 (19.6 – 43.7) 228

20–39 years 3.50 (2.79 – 4.38) .804 (.519 – 1.20) 3.42 (2.99 – 4.15) 11.5 (7.33 – 21.7) 117

40–59 years 3.83 (3.11 – 4.70) 1.27† (.640 – 1.40) 3.78 (3.16 – 4.90) 11.4† (8.79 – 26.7) 85

60 years and older 3.88 (2.81 – 5.35) 1.16† (< LOD – 1.91) 4.17 (3.23 – 5.83) 10.5† (7.12 – 60.1) 83

Females

Total, 6 years and older 6.48 (5.83 – 7.21) 1.57 (1.37 – 1.84) 5.75 (4.93 – 6.55) 29.0 (24.0 – 34.5) 662

6–11 years 11.7 (9.26 – 14.8) 2.14 (1.07 – 3.77) 10.9 (8.65 – 13.4) 88.9 (28.8 – 177) 119

12–19 years 6.12 (5.10 – 7.36) 1.59 (1.13 – 1.80) 5.50 (4.49 – 6.06) 24.0 (15.6 – 40.4) 217

20–39 years 6.39 (5.00 – 8.15) 1.62 (1.14 – 2.09) 5.39 (4.01 – 7.25) 30.4 (19.7 – 58.3) 165

40–59 years 4.74 (3.71 – 6.04) .933† (< LOD – 1.67) 4.23 (3.33 – 5.37) 21.0† (13.1 – 31.3) 72

60 years and older 6.28 (4.18 – 9.43) 1.82† (< LOD – 2.38) 5.43 (3.77 – 8.92) 24.4† (11.9 – 201) 89

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 399

Table 4.6.a.4. Urinary equol (creatinine corrected): Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic blacks 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 5.02 (4.48 – 5.62) 1.19 (1.02 – 1.41) 4.88 (4.40 – 5.59) 20.8 (18.2 – 23.7) 1,340

6–11 years 11.2 (9.38 – 13.3) 3.12 (2.54 – 3.56) 9.67 (7.96 – 11.3) 47.8 (34.3 – 64.1) 207

12–19 years 5.66 (4.86 – 6.60) 1.45 (1.14 – 1.68) 5.37 (4.61 – 6.33) 21.5 (16.8 – 27.9) 496

20–39 years 4.36 (3.81 – 4.98) 1.02 (.802 – 1.36) 4.87 (4.24 – 5.64) 12.3 (10.8 – 17.6) 249

40–59 years 4.33 (3.36 – 5.58) 1.02 (.520 – 1.41) 4.06 (2.87 – 5.29) 19.7 (16.8 – 25.8) 228

60 years and older 4.28 (3.53 – 5.19) 1.08 (.798 – 1.38) 4.22 (3.62 – 5.09) 16.7 (13.6 – 23.6) 160

Males

Total, 6 years and older 4.37 (3.86 – 4.95) 1.01 (.775 – 1.18) 4.24 (3.60 – 4.97) 19.1 (15.2 – 23.4) 658

6–11 years 12.6 (9.98 – 15.9) 3.44† (1.39 – 4.49) 11.0 (8.57 – 14.3) 52.6† (28.7 – 99.7) 99

12–19 years 5.77 (4.53 – 7.34) 1.45 (.957 – 1.76) 5.39 (4.19 – 6.65) 21.7 (15.8 – 36.8) 258

20–39 years 3.73 (3.09 – 4.50) .892 (.630 – 1.05) 3.82 (3.14 – 5.00) 12.1 (10.5 – 15.9) 116

40–59 years 3.18 (2.40 – 4.21) .865† (.471 – 1.24) 2.92 (2.24 – 4.31) 11.6† (6.28 – 27.1) 111

60 years and older 3.04 (2.42 – 3.82) .742† (< LOD – .959) 3.22 (2.07 – 4.15) 13.5† (9.29 – 22.1) 74

Females

Total, 6 years and older 5.63 (4.95 – 6.40) 1.41 (1.18 – 1.59) 5.45 (4.77 – 6.45) 22.1 (18.5 – 25.5) 682

6–11 years 9.92 (7.41 – 13.3) 2.69† (1.59 – 3.38) 8.60 (6.65 – 11.1) 43.5† (30.1 – 68.7) 108

12–19 years 5.56 (4.61 – 6.70) 1.43 (1.03 – 1.81) 5.30 (4.05 – 7.15) 20.9 (16.0 – 28.0) 238

20–39 years 4.94 (4.12 – 5.92) 1.34 (.768 – 1.89) 5.12 (4.53 – 6.44) 12.3 (10.8 – 20.2) 133

40–59 years 5.55 (3.94 – 7.81) 1.12 (.501 – 1.51) 5.32 (3.42 – 7.37) 24.3 (18.4 – 65.6) 117

60 years and older 5.31 (4.14 – 6.80) 1.51† (1.22 – 1.63) 4.81 (3.98 – 6.91) 19.3† (14.1 – 32.3) 86

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.6.a.5. Urinary equol (creatinine corrected): Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic whites 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 8.94 (8.26 – 9.67) 2.12 (1.87 – 2.32) 8.65 (7.95 – 9.50) 32.4 (30.4 – 34.8) 2,106

6–11 years 16.0 (13.4 – 19.0) 4.07 (2.54 – 5.84) 17.1 (14.2 – 20.0) 44.8 (39.0 – 81.4) 193

12–19 years 9.48 (8.25 – 10.9) 2.75 (1.97 – 3.28) 9.27 (8.04 – 10.9) 32.1 (26.2 – 38.2) 378

20–39 years 8.87 (7.54 – 10.4) 1.95 (1.28 – 2.31) 8.50 (7.25 – 9.93) 33.2 (26.3 – 55.1) 494

40–59 years 7.58 (6.57 – 8.75) 1.51 (1.15 – 2.02) 7.18 (6.03 – 8.73) 26.5 (21.7 – 35.0) 447

60 years and older 9.12 (8.02 – 10.4) 2.55 (2.13 – 2.94) 8.66 (7.89 – 9.39) 29.1 (22.3 – 38.7) 594

Males

Total, 6 years and older 8.10 (7.34 – 8.94) 1.91 (1.41 – 2.23) 7.87 (6.92 – 8.89) 30.4 (27.1 – 33.9) 1,034

6–11 years 17.0 (13.8 – 20.9) 4.06† (2.35 – 6.86) 18.4 (15.2 – 21.9) 44.2† (34.9 – 132) 99

12–19 years 9.58 (7.86 – 11.7) 2.18 (1.78 – 3.30) 9.53 (7.67 – 11.5) 32.8 (26.7 – 59.8) 191

20–39 years 7.64 (6.35 – 9.19) 1.59 (1.13 – 2.24) 7.09 (6.21 – 9.30) 28.9 (21.8 – 47.5) 217

40–59 years 6.38 (5.14 – 7.92) 1.17 (.741 – 2.01) 6.44 (4.85 – 7.62) 23.5 (17.7 – 53.0) 228

60 years and older 8.68 (7.23 – 10.4) 2.36 (1.85 – 2.71) 8.31 (6.94 – 9.56) 29.0 (21.6 – 39.1) 299

Females

Total, 6 years and older 9.84 (8.90 – 10.9) 2.32 (2.00 – 2.77) 9.24 (8.62 – 10.3) 34.0 (30.6 – 39.7) 1,072

6–11 years 14.8 (11.2 – 19.7) 4.05† (.890 – 6.10) 14.1 (11.8 – 18.0) 44.8† (36.8 – 90.7) 94

12–19 years 9.37 (7.98 – 11.0) 3.02 (2.28 – 3.55) 8.70 (7.53 – 11.0) 30.7 (21.3 – 37.5) 187

20–39 years 10.3 (8.07 – 13.1) 2.14 (1.19 – 2.98) 9.09 (8.00 – 11.7) 38.3 (29.8 – 75.9) 277

40–59 years 9.02 (7.44 – 10.9) 1.67 (1.22 – 2.59) 8.68 (6.70 – 12.1) 31.7 (21.7 – 44.0) 219

60 years and older 9.49 (7.84 – 11.5) 2.84 (2.12 – 3.20) 8.89 (8.06 – 10.1) 29.4 (21.0 – 49.8) 295

† Estimate is subject to greater uncertainty due to small cell size. 
400 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.6.b. Urinary equol (creatinine corrected): Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 7.70 (6.82 – 8.70) <LOD 7.96 (6.93 – 9.34) 50.0 (43.2 – 67.5) 2,182

 2001–2002 8.60 (7.26 – 10.2) <LOD 7.98 (6.64 – 9.71) 62.5 (52.1 – 87.0) 2,794

 2003–2004 7.52 (6.83 – 8.29) 1.01 (.861 – 1.18) 7.29 (6.56 – 8.18) 50.1 (39.9 – 75.5) 2,590

 2005–2006 8.18 (7.33 – 9.14) 1.08 (.861 – 1.31) 7.92 (7.01 – 8.75) 67.5 (48.6 – 104) 2,527

Age group

6–11 years

 1999–2000 10.3 (7.82 – 13.5) <LOD 11.3 (7.61 – 16.0) 46.6 (33.5 – 151) 272

 2001–2002 13.9 (11.2 – 17.2) <LOD 14.0 (10.6 – 17.0) 80.8 (59.5 – 211) 396

 2003–2004 13.2 (10.9 – 15.9) 2.59 (1.57 – 3.11) 12.9 (9.20 – 17.4) 93.4 (49.7 – 134) 341

 2005–2006 14.7 (12.6 – 17.1) 2.41 (1.21 – 3.27) 15.3 (13.7 – 17.4) 87.6 (57.6 – 267) 351

12–19 years

 1999–2000 7.61 (6.17 – 9.39) <LOD 7.94 (6.84 – 9.24) 47.2 (28.6 – 243) 657

 2001–2002 7.83 (6.68 – 9.17) <LOD 7.76 (6.30 – 9.13) 52.6 (36.0 – 160) 744

 2003–2004 7.90 (6.59 – 9.49) 1.41 (.856 – 1.87) 8.11 (6.82 – 9.03) 40.4 (32.8 – 100) 729

 2005–2006 8.61 (7.53 – 9.83) 1.60 (1.28 – 1.87) 8.03 (7.15 – 9.27) 60.5 (37.4 – 141) 693

20–39 years

 1999–2000 6.20 (5.22 – 7.38) <LOD 6.32 (5.37 – 7.59) 34.1 (30.5 – 50.5) 439

 2001–2002 7.56 (6.16 – 9.27) <LOD 6.83 (5.60 – 8.78) 53.5 (39.0 – 126) 604

 2003–2004 7.42 (6.36 – 8.66) .902 (.750 – 1.26) 6.88 (5.90 – 7.89) 104 (37.2 – 238) 554

 2005–2006 6.90 (5.76 – 8.27) .887 (.644 – 1.06) 7.09 (5.80 – 8.37) 47.2 (32.9 – 171) 583

40–59 years

 1999–2000 7.84 (6.30 – 9.76) <LOD 8.06 (6.05 – 9.76) 69.0 (41.9 – 1,680) 378

 2001–2002 8.86 (7.19 – 10.9) <LOD 7.83 (6.18 – 9.71) 81.9 (55.3 – 138) 531

 2003–2004 6.40 (5.47 – 7.49) .777 (.615 – 1.05) 6.54 (5.03 – 7.69) 38.1 (24.2 – 534) 448

 2005–2006 7.51 (6.01 – 9.39) .895 (.343 – 1.34) 6.61 (5.24 – 8.53) 108 (35.1 – 734) 449

60 years and older

 1999–2000 9.72 (8.33 – 11.3) <LOD 9.63 (7.42 – 11.3) 80.7 (41.1 – 448) 436

 2001–2002 8.50 (7.02 – 10.3) <LOD 7.78 (6.48 – 10.1) 63.7 (38.1 – 161) 519

 2003–2004 7.28 (6.19 – 8.56) 1.27 (<LOD – 1.52) 7.63 (6.22 – 8.79) 33.7 (24.8 – 256) 518

 2005–2006 9.09 (7.93 – 10.4) 1.38 (1.09 – 1.82) 8.40 (7.49 – 9.42) 51.1 (34.1 – 291) 451

Gender

Males

 1999–2000 7.01 (5.93 – 8.29) <LOD 7.31 (5.71 – 8.74) 53.8 (38.9 – 88.4) 1,042

 2001–2002 7.66 (6.39 – 9.18) <LOD 7.43 (5.83 – 9.14) 53.9 (40.7 – 75.8) 1,375

 2003–2004 6.71 (6.02 – 7.47) .912 (.762 – 1.09) 6.62 (5.80 – 7.28) 51.0 (38.7 – 76.6) 1,240

 2005–2006 7.35 (6.40 – 8.43) .984 (.599 – 1.25) 7.02 (5.94 – 8.63) 57.4 (43.3 – 85.6) 1,252

Females

 1999–2000 8.41 (7.33 – 9.66) <LOD 8.71 (7.52 – 10.2) 46.2 (43.1 – 55.6) 1,140

 2001–2002 9.60 (7.99 – 11.5) <LOD 8.66 (7.02 – 10.6) 84.6 (62.4 – 118) 1,419

 2003–2004 8.38 (7.39 – 9.51) 1.15 (.893 – 1.53) 8.29 (7.08 – 9.29) 45.4 (39.0 – 103) 1,350

 2005–2006 9.07 (8.04 – 10.2) 1.24 (.885 – 1.41) 8.48 (7.90 – 9.19) 83.5 (53.4 – 165) 1,275

Race/ethnicity

Mexican Americans

 1999–2000 4.89 (4.36 – 5.47) <LOD 4.73 (3.90 – 5.23) 37.0 (26.7 – 62.3) 726

 2001–2002 6.79 (5.82 – 7.92) <LOD 6.81 (5.66 – 8.02) 41.2 (34.5 – 54.2) 679

 2003–2004 5.48 (4.60 – 6.54) .932 (.609 – 1.17) 4.69 (4.02 – 5.77) 35.5 (29.2 – 113) 653

 2005–2006 5.45 (4.84 – 6.14) .738 (.548 – 1.02) 4.98 (4.38 – 5.85) 39.4 (31.9 – 81.2) 634

Non-Hispanic Blacks

 1999–2000 4.31 (3.36 – 5.52) <LOD 4.54 (2.90 – 6.22) 25.8 (20.3 – 33.3) 504

 2001–2002 4.96 (4.19 – 5.86) <LOD 4.37 (3.70 – 5.41) 35.2 (25.4 – 47.4) 692

 2003–2004 5.17 (4.38 – 6.10) .759 (.484 – .958) 5.18 (4.67 – 5.97) 29.7 (24.9 – 51.5) 678

 2005–2006 4.88 (4.11 – 5.78) .769 (.595 – 1.02) 4.72 (3.58 – 5.98) 31.0 (25.4 – 53.3) 662

Non-Hispanic Whites

 1999–2000 9.31 (8.01 – 10.8) <LOD 9.57 (7.91 – 11.2) 56.2 (46.6 – 73.0) 744

 2001–2002 9.77 (7.86 – 12.1) <LOD 9.14 (7.06 – 12.1) 65.9 (56.8 – 85.0) 1,211

 2003–2004 8.39 (7.46 – 9.43) 1.11 (.914 – 1.35) 8.17 (7.13 – 9.23) 56.0 (38.7 – 116) 1,068

 2005–2006 9.51 (8.48 – 10.7) 1.31 (1.03 – 1.68) 9.15 (8.06 – 10.5) 77.4 (48.6 – 146) 1,038

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
j j j j 

20 

j 

j 

j 

j 

j j j j j j j j j j 

j j 

j j j j 

j 

j 

j j j j 

j j 

j j 

j 

j 

j 

j 

j 

j 

0 

100 

200 

300 

95th Percentile 

j 

j 

j j 

j j 

j 

j j j 

j 

j 

j j j j j 

j 

j 

j 

j j j j 

j j j j 

j j j 

j 

Figure 4.6.b. Urinary equol (creatinine corrected): 

Concentrations by survey cycle 

Selected percentiles in μg/g creatinine (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006 

5th Percentile 50th Percentile

15 

10 

5 

0 

4 

3 

2 

1 

0 

j j 

j 

j 

j 

j 

j j j j 

j j 

j 

j j j 

j 

j 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

4. Isoflavones and Lignans 401
402

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.7.a.1. Urinary O-desmethylangolensin: Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 4.80 (4.42 – 5.22) < LOD < LOD 4.09 (3.67 – 4.53) 251 (216 – 322) 524 (462 – 612) 5,109Age group6–11 years 6.74 (5.30 – 8.59) < LOD .233 (< LOD – .372) 6.17 (4.56 – 8.88) 231 (164 – 371) 445 (361 – 547) 692

12–19 years 7.35 (6.18 – 8.74) < LOD < LOD 6.38 (5.25 – 8.33) 285 (229 – 451) 607 (406 – 1,010) 1,422

20–39 years 4.13 (3.52 – 4.86) < LOD < LOD 3.32 (2.79 – 3.90) 242 (165 – 400) 485 (402 – 651) 1,129

40–59 years 4.42 (3.81 – 5.13) < LOD < LOD 3.88 (2.93 – 5.02) 261 (203 – 481) 657 (385 – 1,150) 899

60 years and older 4.42 (3.69 – 5.30) < LOD < LOD 3.71 (2.97 – 4.90) 191 (128 – 404) 455 (341 – 928) 967

GenderMales 4.92 (4.29 – 5.63) < LOD < LOD 4.21 (3.60 – 5.20) 223 (190 – 299) 476 (383 – 563) 2,492

Females 4.70 (4.26 – 5.18) < LOD < LOD 3.92 (3.35 – 4.56) 283 (209 – 406) 649 (455 – 938) 2,617

Race/ethnicityMexican Americans 2.79 (2.29 – 3.39) < LOD < LOD 1.93 (1.34 – 2.62) 147 (108 – 226) 304 (227 – 422) 1,286

Non-Hispanic Blacks 5.69 (4.70 – 6.90) < LOD < LOD 4.56 (3.88 – 5.72) 279 (208 – 378) 531 (384 – 877) 1,342

Non-Hispanic Whites 4.99 (4.55 – 5.46) < LOD < LOD 4.35 (3.90 – 5.12) 245 (201 – 339) 525 (433 – 696) 2,100

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
6−11 12−19 20−39 40−59 60+ 

0 5 10 15 20

Urinary O−desmethylangolensin (μg/L) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

20 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 4.7.a. Urinary O−desmethylangolensin: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary O−desmethylangolensin Urinary O−desmethylangolensin (μg/L) (μg/L) 0 5 10 15 20 0 5 10 15 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

4. Isoflavones and Lignans 403
404 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.7.a.2. Urinary O-desmethylangolensin: Total population

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 

years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 4.80 (4.42 – 5.22) .243 (.210 – .276) 4.09 (3.67 – 4.53) 97.6 (88.0 – 115) 5,109

6–11 years 6.74 (5.30 – 8.59) .472 (.297 – .655) 6.17 (4.56 – 8.88) 107 (74.1 – 159) 692

12–19 years 7.35 (6.18 – 8.74) .397 (.300 – .479) 6.38 (5.25 – 8.33) 108 (89.5 – 171) 1,422

20–39 years 4.13 (3.52 – 4.86) .228 (< LOD – .276) 3.32 (2.79 – 3.90) 86.5 (65.6 – 136) 1,129

40–59 years 4.42 (3.81 – 5.13) < LOD 3.88 (2.93 – 5.02) 114 (71.0 – 181) 899

60 years and older 4.42 (3.69 – 5.30) .237 (< LOD – .293) 3.71 (2.97 – 4.90) 84.9 (60.5 – 116) 967

Males

Total, 6 years and older 4.92 (4.29 – 5.63) .280 (.231 – .328) 4.21 (3.60 – 5.20) 91.2 (73.4 – 117) 2,492

6–11 years 6.83 (4.77 – 9.78) .501 (.234 – .705) 5.60 (3.59 – 9.19) 117 (69.6 – 238) 340

12–19 years 9.13 (7.17 – 11.6) .433 (.341 – .546) 8.73 (6.49 – 11.5) 127 (102 – 253) 728

20–39 years 4.38 (3.41 – 5.61) .213 (< LOD – .299) 3.63 (3.06 – 4.49) 89.8 (63.3 – 175) 498

40–59 years 4.04 (3.27 – 4.99) .278 (.207 – .339) 3.34 (2.48 – 4.96) 69.6 (52.0 – 138) 451

60 years and older 4.39 (3.39 – 5.69) .261 (< LOD – .363) 4.05 (3.01 – 5.43) 75.8 (54.6 – 103) 475

Females

Total, 6 years and older 4.70 (4.26 – 5.18) .213 (< LOD – .258) 3.92 (3.35 – 4.56) 105 (80.6 – 151) 2,617

6–11 years 6.65 (5.16 – 8.58) .392 (.252 – .653) 6.91 (4.76 – 9.15) 100 (60.7 – 158) 352

12–19 years 5.83 (4.79 – 7.10) .324 (.220 – .480) 4.28 (3.15 – 5.79) 92.9 (71.4 – 104) 694

20–39 years 3.91 (3.12 – 4.89) .244 (< LOD – .300) 2.83 (2.02 – 3.94) 80.6 (58.4 – 155) 631

40–59 years 4.82 (3.87 – 6.01) < LOD 4.46 (3.00 – 6.43) 181 (99.3 – 275) 448

60 years and older 4.45 (3.52 – 5.62) .224 (< LOD – .279) 3.45 (2.71 – 5.36) 88.7 (59.8 – 153) 492

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

Table 4.7.a.3. Urinary O-desmethylangolensin: Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/L) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 2.79 (2.29 – 3.39) < LOD 1.93 (1.34 – 2.62) 62.4 (50.0 – 89.5) 1,286

6–11 years 6.57 (4.75 – 9.07) .446 (.306 – .603) 6.92 (3.88 – 11.0) 103 (58.3 – 189) 231

12–19 years 6.38 (4.66 – 8.73) .324 (.213 – .396) 5.77 (4.16 – 8.32) 134 (87.6 – 271) 445

20–39 years 1.92 (1.45 – 2.53) < LOD 1.06 (.693 – 1.53) 58.2 (24.5 – 110) 281

40–59 years 1.91 (1.41 – 2.59) < LOD 1.21 (.806 – 2.20) 31.7 (21.3 – 70.6) 157

60 years and older 2.15 (1.43 – 3.23) < LOD 1.47 (.853 – 2.99) 27.9 (17.2 – 50.3) 172

Males

Total, 6 years and older 2.83 (2.20 – 3.65) < LOD 1.92 (1.23 – 2.79) 61.5 (47.3 – 89.9) 625

6–11 years 7.12 (4.64 – 10.9) .506 (.307 – .700) 7.04 (2.90 – 15.9) 115 (61.2 – 275) 112

12–19 years 6.77 (4.40 – 10.4) .365 (.241 – .462) 6.56 (3.54 – 11.1) 122 (55.4 – 286) 228

20–39 years 1.71 (1.16 – 2.51) < LOD .783 (.607 – 1.47) 39.2 (18.1 – 121) 117

40–59 years 2.46 (1.55 – 3.91) < LOD† 1.80 (.755 – 3.23) 48.1† (21.9 – 342) 85

60 years and older 2.19 (1.09 – 4.41) < LOD† 1.39 (.695 – 5.52) 21.6† (14.0 – 607) 83

Females

Total, 6 years and older 2.74 (2.17 – 3.45) < LOD 1.97 (1.27 – 2.85) 64.9 (39.2 – 111) 661

6–11 years 6.03 (4.19 – 8.68) .378 (.290 – .531) 6.65 (3.89 – 10.5) 81.9 (32.7 – 296) 119

12–19 years 5.99 (4.33 – 8.29) .302 (< LOD – .381) 4.71 (3.81 – 7.61) 176 (93.4 – 325) 217

20–39 years 2.20 (1.33 – 3.63) < LOD 1.31 (.772 – 2.43) 63.7 (19.3 – 235) 164

40–59 years 1.45 (.886 – 2.38) < LOD† 1.06 (.513 – 1.97) 20.7† (10.1 – 73.1) 72

60 years and older 2.12 (1.13 – 3.98) < LOD† 1.45 (.808 – 4.19) 38.7† (11.3 – 1,390) 89

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 405

Table 4.7.a.4. Urinary O-desmethylangolensin: Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 5.69 (4.70 – 6.90) .267 (.210 – .342) 4.56 (3.88 – 5.72) 113 (89.0 – 157) 1,342

6–11 years 10.6 (7.76 – 14.4) .639 (.244 – 1.24) 11.1 (7.91 – 16.4) 164 (106 – 338) 207

12–19 years 9.85 (8.13 – 11.9) .565 (.391 – .896) 10.2 (7.23 – 15.0) 121 (100 – 172) 496

20–39 years 4.31 (3.05 – 6.07) < LOD 3.25 (2.16 – 4.64) 90.8 (51.6 – 170) 249

40–59 years 5.54 (4.02 – 7.64) .265 (< LOD – .380) 4.61 (2.91 – 7.10) 124 (80.1 – 220) 231

60 years and older 3.60 (2.02 – 6.39) .215 (< LOD – .279) 2.57 (1.49 – 4.67) 82.6 (47.3 – 341) 159

Males

Total, 6 years and older 6.62 (5.17 – 8.47) .297 (.206 – .458) 5.48 (4.13 – 8.91) 114 (90.2 – 168) 660

6–11 years 11.9 (7.59 – 18.6) .854† (.360 – 1.53) 10.8 (5.47 – 20.0) 182† (106 – 764) 99

12–19 years 11.4 (8.83 – 14.7) .580 (.376 – .969) 12.7 (7.98 – 17.0) 145 (111 – 241) 258

20–39 years 6.79 (3.90 – 11.8) .226 (< LOD – .614) 4.57 (2.91 – 12.9) 122 (82.3 – 400) 116

40–59 years 4.89 (3.12 – 7.67) .244 (< LOD – .474) 4.83 (2.15 – 9.22) 69.3 (46.5 – 216) 114

60 years and older 2.91 (1.60 – 5.30) .212† (< LOD – .298) 2.70 (1.05 – 4.21) 48.7† (20.0 – 868) 73

Females

Total, 6 years and older 5.01 (3.87 – 6.50) .246 (< LOD – .334) 4.09 (2.94 – 5.38) 112 (82.0 – 160) 682

6–11 years 9.36 (6.05 – 14.5) .364† (< LOD – 1.11) 11.9 (7.46 – 16.4) 121† (56.0 – 502) 108

12–19 years 8.51 (6.68 – 10.8) .551 (.259 – .963) 7.87 (5.52 – 14.0) 98.0 (77.3 – 143) 238

20–39 years 2.98 (1.78 – 5.01) < LOD 2.17 (1.14 – 4.46) 49.2 (27.2 – 160) 133

40–59 years 6.15 (3.81 – 9.90) .280 (.207 – .388) 4.44 (2.60 – 8.52) 203 (106 – 486) 117

60 years and older 4.11 (1.92 – 8.80) .217† (< LOD – .363) 2.45 (1.37 – 8.03) 91.7† (67.0 – 322) 86

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.7.a.5. Urinary O-desmethylangolensin: Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic whites in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 4.99 (4.55 – 5.46) .247 (.201 – .293) 4.35 (3.90 – 5.12) 97.9 (86.2 – 123) 2,100

6–11 years 6.20 (4.18 – 9.18) .443 (< LOD – .679) 5.49 (3.39 – 9.17) 95.4 (60.4 – 203) 193

12–19 years 7.55 (5.92 – 9.63) .401 (.259 – .571) 6.85 (5.13 – 9.64) 103 (85.0 – 205) 378

20–39 years 4.64 (3.67 – 5.85) .264 (< LOD – .331) 3.71 (2.94 – 5.33) 104 (65.2 – 161) 488

40–59 years 4.54 (3.75 – 5.51) < LOD 4.14 (2.91 – 5.62) 121 (67.5 – 185) 447

60 years and older 4.67 (3.89 – 5.60) .248 (< LOD – .320) 4.09 (3.25 – 5.34) 84.4 (57.6 – 117) 594

Males

Total, 6 years and older 4.88 (4.11 – 5.80) .290 (.217 – .350) 4.21 (3.40 – 5.41) 88.8 (67.8 – 120) 1,034

6–11 years 5.78 (3.26 – 10.3) .445† (< LOD – .719) 4.99 (1.97 – 10.4) 88.6† (40.8 – 580) 99

12–19 years 9.72 (7.00 – 13.5) .429 (.295 – .611) 9.13 (6.14 – 13.6) 125 (88.5 – 365) 191

20–39 years 4.46 (3.13 – 6.36) .236 (< LOD – .365) 3.56 (2.79 – 5.63) 78.4 (48.1 – 189) 217

40–59 years 4.09 (3.19 – 5.24) .294 (.201 – .354) 3.02 (2.28 – 5.24) 70.4 (51.0 – 170) 229

60 years and older 4.58 (3.35 – 6.27) .266 (< LOD – .384) 4.17 (3.21 – 6.29) 72.6 (50.6 – 103) 298

Females

Total, 6 years and older 5.09 (4.45 – 5.82) .209 (< LOD – .277) 4.53 (3.79 – 5.58) 112 (74.9 – 175) 1,066

6–11 years 6.72 (4.42 – 10.2) .438† (< LOD – .745) 6.05 (3.68 – 12.2) 105† (48.1 – 310) 94

12–19 years 5.73 (4.21 – 7.80) .299 (< LOD – .615) 3.99 (2.90 – 8.09) 88.8 (61.2 – 170) 187

20–39 years 4.83 (3.50 – 6.66) .295 (.221 – .349) 3.90 (2.73 – 6.07) 114 (58.4 – 303) 271

40–59 years 5.06 (3.68 – 6.95) < LOD 5.51 (2.99 – 7.16) 181 (67.3 – 333) 218

60 years and older 4.74 (3.78 – 5.94) .237 (< LOD – .311) 3.90 (2.86 – 6.17) 85.9 (53.0 – 168) 296

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 
406 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.7.b. Urinary O-desmethylangolensin: Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 4.39 (3.37 – 5.73) < LOD 4.97 (3.67 – 6.74) 218 (186 – 247) 2,271

 2001–2002 4.08 (3.53 – 4.73) < LOD 3.30 (2.64 – 4.11) 260 (177 – 492) 2,794

 2003–2004 4.91 (4.34 – 5.55) < LOD 4.55 (3.99 – 5.16) 229 (186 – 364) 2,581

 2005–2006 4.70 (4.17 – 5.31) < LOD 3.70 (3.14 – 4.25) 264 (213 – 386) 2,528

Age group

6–11 years

 1999–2000 5.60 (3.85 – 8.15) < LOD 7.48 (3.42 – 15.1) 175 (79.4 – 273) 287

 2001–2002 6.19 (4.51 – 8.49) < LOD 5.85 (3.88 – 9.42) 278 (177 – 522) 396

 2003–2004 6.32 (4.30 – 9.30) .319 (< LOD – .590) 6.07 (3.48 – 10.5) 137 (92.3 – 283) 341

 2005–2006 7.20 (5.20 – 9.96) < LOD 6.16 (3.98 – 10.9) 356 (207 – 506) 351

12–19 years

 1999–2000 6.04 (3.76 – 9.70) < LOD 7.58 (5.18 – 13.2) 194 (136 – 301) 667

 2001–2002 5.92 (4.46 – 7.86) < LOD 5.19 (3.72 – 7.59) 298 (179 – 435) 744

 2003–2004 6.36 (4.95 – 8.18) < LOD 5.27 (3.89 – 8.00) 256 (179 – 416) 729

 2005–2006 8.50 (6.48 – 11.2) .244 (< LOD – .337) 8.06 (5.57 – 11.6) 380 (168 – 869) 693

20–39 years

 1999–2000 4.00 (2.73 – 5.86) < LOD 4.44 (2.77 – 5.87) 306 (252 – 462) 481

 2001–2002 3.36 (2.61 – 4.34) < LOD 2.48 (1.80 – 3.00) 248 (128 – 680) 604

 2003–2004 4.25 (3.24 – 5.58) < LOD 3.65 (2.74 – 4.89) 317 (154 – 483) 546

 2005–2006 4.03 (3.29 – 4.93) < LOD 3.00 (2.17 – 3.78) 235 (154 – 336) 583

40–59 years

 1999–2000 4.20 (3.13 – 5.62) < LOD 4.24 (2.78 – 6.11) 171 (119 – 304) 365

 2001–2002 5.07 (3.45 – 7.46) < LOD 4.39 (2.61 – 7.20) 381 (206 – 1,000) 531

 2003–2004 5.13 (4.34 – 6.07) < LOD 5.13 (3.52 – 6.44) 222 (180 – 753) 450

 2005–2006 3.84 (2.97 – 4.97) < LOD 2.92 (1.72 – 4.29) 274 (214 – 587) 449

60 years and older

 1999–2000 3.93 (2.75 – 5.62) < LOD 4.80 (3.04 – 8.37) 111 (74.5 – 185) 471

 2001–2002 2.32 (1.83 – 2.94) < LOD 1.73 (1.16 – 2.30) 98.3 (70.6 – 464) 519

 2003–2004 4.17 (3.09 – 5.63) < LOD 3.69 (2.71 – 5.88) 203 (129 – 394) 515

 2005–2006 4.68 (3.70 – 5.91) < LOD 3.76 (2.74 – 5.45) 171 (92.6 – 486) 452

Gender

Males

 1999–2000 4.97 (3.71 – 6.66) < LOD 5.62 (4.23 – 8.78) 234 (180 – 332) 1,087

 2001–2002 3.81 (3.08 – 4.71) < LOD 3.29 (2.52 – 4.38) 194 (134 – 356) 1,375

 2003–2004 4.90 (3.93 – 6.12) < LOD 4.53 (3.32 – 5.49) 221 (163 – 359) 1,240

 2005–2006 4.93 (4.13 – 5.89) < LOD 3.99 (3.34 – 5.43) 234 (178 – 341) 1,252

Females

 1999–2000 3.92 (2.97 – 5.16) < LOD 4.22 (3.24 – 5.48) 191 (149 – 245) 1,184

 2001–2002 4.36 (3.64 – 5.23) < LOD 3.34 (2.47 – 4.50) 377 (232 – 750) 1,419

 2003–2004 4.91 (4.26 – 5.66) < LOD 4.59 (3.91 – 5.51) 277 (168 – 450) 1,341

 2005–2006 4.50 (3.90 – 5.20) < LOD 3.29 (2.71 – 4.24) 283 (199 – 499) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 2.40 (1.55 – 3.73) < LOD 2.14 (1.40 – 3.43) 191 (128 – 323) 721

 2001–2002 2.44 (1.51 – 3.94) < LOD 1.38 (.501 – 3.33) 151 (80.1 – 498) 679

 2003–2004 2.54 (1.86 – 3.48) < LOD 1.85 (.928 – 3.30) 141 (105 – 272) 652

 2005–2006 3.04 (2.29 – 4.05) < LOD 2.00 (1.36 – 2.84) 151 (95.3 – 271) 634

Non-Hispanic Blacks

 1999–2000 5.75 (4.60 – 7.20) < LOD 8.78 (5.90 – 10.9) 184 (138 – 320) 527

 2001–2002 5.38 (4.01 – 7.21) < LOD 5.19 (3.04 – 7.31) 308 (193 – 430) 692

 2003–2004 5.55 (4.07 – 7.57) < LOD 4.21 (3.25 – 6.49) 219 (182 – 375) 680

 2005–2006 5.83 (4.49 – 7.58) < LOD 4.84 (3.94 – 6.45) 292 (173 – 471) 662

Non-Hispanic Whites

 1999–2000 4.53 (3.23 – 6.37) < LOD 4.98 (3.38 – 7.14) 225 (189 – 255) 810

 2001–2002 4.13 (3.44 – 4.96) < LOD 3.35 (2.61 – 4.32) 261 (178 – 546) 1,211

 2003–2004 5.28 (4.65 – 5.99) < LOD 5.23 (4.53 – 5.78) 242 (186 – 407) 1,061

 2005–2006 4.72 (4.09 – 5.45) < LOD 3.72 (3.21 – 4.59) 246 (184 – 391) 1,039

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
5th Percentile 50th Percentile 95th Percentile

1000 

800 

600 

400 

200 

0 

20 

15 

10 

5 

0 

800 

600 

400 

200 

0 

H 

H H H 

H 

H 

H 

H 

H 

H 

H 

H 

H H H H H 

H H H 

H 

H 

H H 

H 

H H H H 

H 

H 

H 

H H H H 

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H 

H H 

H 

H 

H 

H 

H 

H 

H 

H H H 

H 

H 

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H H H H 

H 

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H 

H 

H 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

Figure 4.7.b. Urinary O−desmethylangolensin: Concentrations by survey cycle 

Selected percentiles in μg/L (95% confidence intervals), National Health and 


Nutrition Examination Survey, 1999–2006
 

4. Isoflavones and Lignans 407
408

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.8.a.1. Urinary O-desmethylangolensin (creatinine corrected): Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 4.58 (4.25 – 4.94) < LOD < LOD 3.89 (3.51 – 4.33) 204 (193 – 260) 530 (376 – 725) 5,109Age group6–11 years 7.31 (5.72 – 9.33) < LOD .349 (< LOD – .470) 6.11 (4.49 – 8.22) 243 (175 – 349) 362 (317 – 611) 692

12–19 years 5.47 (4.64 – 6.46) < LOD < LOD 4.67 (3.74 – 6.52) 201 (136 – 375) 456 (270 – 713) 1,422

20–39 years 3.51 (3.05 – 4.04) < LOD < LOD 3.10 (2.38 – 3.74) 181 (144 – 260) 425 (241 – 646) 1,129

40–59 years 4.48 (3.89 – 5.16) < LOD < LOD 3.51 (2.96 – 4.33) 243 (194 – 532) 795 (343 – 1,270) 899

60 years and older 5.18 (4.38 – 6.13) < LOD < LOD 4.37 (3.42 – 5.80) 239 (140 – 389) 480 (317 – 1,730) 967

GenderMales 3.90 (3.42 – 4.44) < LOD < LOD 3.41 (2.81 – 4.09) 179 (144 – 227) 325 (256 – 482) 2,492

Females 5.35 (4.85 – 5.91) < LOD < LOD 4.40 (3.76 – 5.25) 271 (202 – 396) 738 (548 – 1,020) 2,617

Race/ethnicityMexican Americans 2.51 (2.01 – 3.14) < LOD < LOD 1.68 (1.09 – 2.45) 130 (93.0 – 158) 243 (164 – 423) 1,286

Non-Hispanic Blacks 4.00 (3.35 – 4.77) < LOD < LOD 3.47 (2.48 – 4.61) 180 (136 – 313) 512 (292 – 876) 1,342

Non-Hispanic Whites 5.07 (4.68 – 5.49) < LOD < LOD 4.30 (3.85 – 4.69) 227 (194 – 274) 557 (338 – 824) 2,100

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
6−11 12−19 20−39 40−59 60+ 

0 5 10 15 20

Urinary O−desmethylangolensin (μg/g creatinine) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 4.8.a. Urinary O−desmethylangolensin (creatinine corrected): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary O−desmethylangolensin Urinary O−desmethylangolensin (μg/g creatinine) (μg/g creatinine) 0 5 10 15 20 0 5 10 15 20 

Non−Hispanic Blacks 

6−11 12−19 20−39 40−59 60+ 

Females 

6−11 12−19 20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

6−11 12−19 20−39 40−59 60+ 

Males 

6−11 12−19 20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

4. Isoflavones and Lignans 409
410 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.8.a.2. Urinary O-desmethylangolensin (creatinine corrected): 

Total population

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 4.58 (4.25 – 4.94) .312 (.289 – .338) 3.89 (3.51 – 4.33) 93.2 (81.6 – 109) 5,109

6–11 years 7.31 (5.72 – 9.33) .587 (.389 – .800) 6.11 (4.49 – 8.22) 109 (84.7 – 165) 692

12–19 years 5.47 (4.64 – 6.46) .320 (.289 – .402) 4.67 (3.74 – 6.52) 86.1 (61.4 – 129) 1,422

20–39 years 3.51 (3.05 – 4.04) .248 (< LOD – .299) 3.10 (2.38 – 3.74) 78.0 (63.1 – 97.3) 1,129

40–59 years 4.48 (3.89 – 5.16) < LOD 3.51 (2.96 – 4.33) 138 (76.1 – 190) 899

60 years and older 5.18 (4.38 – 6.13) .384 (< LOD – .472) 4.37 (3.42 – 5.80) 79.2 (65.8 – 119) 967

Males

Total, 6 years and older 3.90 (3.42 – 4.44) .281 (.233 – .323) 3.41 (2.81 – 4.09) 73.1 (58.7 – 85.3) 2,492

6–11 years 6.85 (4.87 – 9.63) .496 (.308 – .801) 5.45 (3.39 – 8.21) 126 (81.4 – 215) 340

12–19 years 6.19 (4.90 – 7.82) .315 (.219 – .487) 6.40 (4.16 – 8.62) 94.4 (61.8 – 169) 728

20–39 years 3.19 (2.53 – 4.03) .196 (< LOD – .283) 2.68 (2.00 – 4.15) 67.3 (46.0 – 93.6) 498

40–59 years 3.20 (2.57 – 3.99) .251 (.200 – .312) 2.76 (2.03 – 3.84) 51.5 (37.2 – 94.2) 451

60 years and older 4.03 (3.22 – 5.05) .341 (< LOD – .424) 3.75 (2.54 – 5.01) 64.8 (40.6 – 107) 475

Females

Total, 6 years and older 5.35 (4.85 – 5.91) .342 (< LOD – .385) 4.40 (3.76 – 5.25) 131 (95.9 – 158) 2,617

6–11 years 7.83 (6.01 – 10.2) .682 (.379 – .857) 7.16 (5.34 – 9.21) 100 (77.5 – 164) 352

12–19 years 4.80 (4.03 – 5.72) .321 (.278 – .392) 4.02 (3.17 – 4.75) 74.9 (54.2 – 120) 694

20–39 years 3.86 (3.08 – 4.83) .301 (< LOD – .337) 3.44 (2.23 – 4.59) 86.8 (63.3 – 139) 631

40–59 years 6.16 (5.10 – 7.43) < LOD 5.00 (3.20 – 6.49) 192 (152 – 316) 448

60 years and older 6.31 (4.96 – 8.01) .426 (< LOD – .643) 5.49 (3.84 – 7.18) 102 (74.4 – 155) 492

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 

Table 4.8.a.3. Urinary O-desmethylangolensin (creatinine corrected): 

Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for Mexican Americans in 

the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 2.51 (2.01 – 3.14) < LOD 1.68 (1.09 – 2.45) 52.7 (39.7 – 74.3) 1,286

6–11 years 8.24 (6.07 – 11.2) .539 (.345 – .845) 7.19 (4.88 – 12.9) 102 (73.3 – 160) 231

12–19 years 4.93 (3.63 – 6.69) .295 (.240 – .365) 4.46 (3.00 – 6.97) 103 (59.6 – 155) 445

20–39 years 1.55 (1.12 – 2.14) < LOD .843 (.692 – 1.16) 33.8 (17.5 – 80.4) 281

40–59 years 1.75 (1.28 – 2.40) < LOD 1.01 (.818 – 2.03) 27.3 (22.5 – 52.6) 157

60 years and older 2.66 (1.82 – 3.88) < LOD 1.95 (1.08 – 3.72) 35.9 (25.1 – 63.6) 172

Males

Total, 6 years and older 2.24 (1.69 – 2.96) < LOD 1.33 (.935 – 2.07) 45.9 (34.6 – 74.9) 625

6–11 years 8.54 (5.71 – 12.8) .532 (.307 – 1.03) 7.44 (4.18 – 16.7) 110 (72.7 – 274) 112

12–19 years 4.90 (3.18 – 7.55) .292 (.208 – .428) 4.55 (2.36 – 10.5) 103 (43.8 – 146) 228

20–39 years 1.24 (.818 – 1.88) < LOD .732 (.591 – .930) 28.8 (13.4 – 95.5) 117

40–59 years 1.81 (1.17 – 2.79) < LOD† .997 (.601 – 3.02) 36.6† (16.9 – 156) 85

60 years and older 1.96 (1.00 – 3.82) < LOD† 1.44 (.646 – 3.16) 20.4† (12.1 – 159) 83

Females

Total, 6 years and older 2.86 (2.22 – 3.68) < LOD 2.16 (1.36 – 3.15) 59.6 (41.4 – 96.0) 661

6–11 years 7.94 (5.56 – 11.4) .527 (.268 – .811) 6.00 (4.39 – 12.1) 93.0 (62.8 – 156) 119

12–19 years 4.95 (3.71 – 6.60) .295 (< LOD – .342) 4.20 (2.93 – 6.89) 100 (72.2 – 243) 217

20–39 years 2.01 (1.21 – 3.35) < LOD 1.01 (.703 – 2.25) 40.5 (13.8 – 203) 164

40–59 years 1.69 (1.02 – 2.80) < LOD† 1.01 (.870 – 2.39) 27.1† (16.3 – 66.5) 72

60 years and older 3.41 (1.90 – 6.13) < LOD† 2.79 (1.08 – 7.40) 45.9† (23.0 – 803) 89

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 411

Table 4.8.a.4. Urinary O-desmethylangolensin (creatinine corrected): 

Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic blacks 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 4.00 (3.35 – 4.77) .249 (.208 – .295) 3.47 (2.48 – 4.61) 75.6 (60.8 – 97.4) 1,342

6–11 years 9.91 (7.22 – 13.6) .701 (.469 – .983) 10.1 (7.06 – 15.0) 160 (85.0 – 249) 207

12–19 years 5.66 (4.68 – 6.84) .336 (.262 – .519) 6.00 (4.57 – 8.05) 72.7 (53.8 – 100) 496

20–39 years 2.67 (1.93 – 3.69) < LOD 1.99 (1.21 – 3.33) 45.7 (34.3 – 82.1) 249

40–59 years 4.03 (3.01 – 5.39) .241 (< LOD – .319) 3.60 (1.85 – 6.21) 77.7 (58.0 – 133) 231

60 years and older 3.20 (1.86 – 5.51) .194 (< LOD – .342) 2.34 (1.45 – 4.24) 73.0 (30.4 – 296) 159

Males

Total, 6 years and older 3.86 (3.06 – 4.88) .233 (.157 – .322) 3.81 (2.31 – 4.93) 69.7 (52.6 – 92.1) 660

6–11 years 11.2 (7.16 – 17.6) .797† (.574 – 1.50) 10.7 (5.44 – 15.8) 173† (85.5 – 476) 99

12–19 years 6.09 (4.69 – 7.91) .324 (.199 – .529) 6.53 (4.50 – 9.81) 81.0 (52.5 – 137) 258

20–39 years 3.26 (1.91 – 5.56) .157 (< LOD – .342) 2.38 (1.20 – 6.28) 62.5 (41.0 – 133) 116

40–59 years 2.80 (1.83 – 4.28) .194 (< LOD – .310) 2.10 (1.14 – 5.38) 46.0 (20.8 – 121) 114

60 years and older 2.12 (1.13 – 3.98) .146† (< LOD – .217) 1.87 (.716 – 3.04) 28.2† (12.9 – 664) 73

Females

Total, 6 years and older 4.11 (3.19 – 5.30) .265 (< LOD – .330) 3.28 (2.29 – 5.29) 78.9 (62.4 – 126) 682

6–11 years 8.73 (5.75 – 13.3) .509† (< LOD – 1.10) 9.53 (5.79 – 15.3) 145† (55.0 – 522) 108

12–19 years 5.25 (4.09 – 6.74) .338 (.222 – .575) 5.33 (3.56 – 8.34) 56.7 (46.9 – 78.1) 238

20–39 years 2.27 (1.36 – 3.79) < LOD 1.83 (.829 – 4.09) 34.9 (21.9 – 122) 133

40–59 years 5.45 (3.42 – 8.68) .276 (.197 – .411) 4.28 (1.91 – 7.76) 148 (74.5 – 835) 117

60 years and older 4.15 (2.06 – 8.34) .334† (< LOD – .461) 2.59 (1.22 – 6.75) 88.1† (36.1 – 366) 86

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.8.a.5. Urinary O-desmethylangolensin (creatinine corrected): 

Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic whites 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 5.07 (4.68 – 5.49) .347 (.312 – .382) 4.30 (3.85 – 4.69) 100 (86.1 – 136) 2,100

6–11 years 6.72 (4.52 – 9.99) .515 (< LOD – .823) 5.35 (3.55 – 8.26) 126 (75.5 – 219) 193

12–19 years 5.92 (4.64 – 7.57) .342 (.259 – .492) 4.83 (3.42 – 8.22) 91.6 (59.4 – 149) 378

20–39 years 4.25 (3.40 – 5.30) .321 (< LOD – .376) 3.90 (3.10 – 4.89) 86.6 (67.4 – 129) 488

40–59 years 4.89 (4.13 – 5.79) < LOD 3.75 (3.03 – 4.81) 160 (88.4 – 194) 447

60 years and older 5.57 (4.72 – 6.57) .417 (< LOD – .498) 4.76 (3.87 – 6.27) 78.8 (65.6 – 120) 594

Males

Total, 6 years and older 4.08 (3.45 – 4.83) .304 (.237 – .370) 3.57 (2.90 – 4.35) 73.4 (58.4 – 88.8) 1,034

6–11 years 5.60 (3.23 – 9.71) .403† (< LOD – .810) 4.09 (2.17 – 8.47) 109† (43.9 – 358) 99

12–19 years 6.94 (4.98 – 9.67) .311 (.186 – .652) 6.78 (3.52 – 13.0) 103 (58.5 – 260) 191

20–39 years 3.54 (2.51 – 5.00) .257 (< LOD – .350) 3.16 (2.22 – 4.91) 69.1 (48.0 – 95.7) 217

40–59 years 3.42 (2.66 – 4.40) .278 (.191 – .389) 2.96 (2.16 – 3.95) 55.5 (36.3 – 150) 229

60 years and older 4.27 (3.25 – 5.62) .354 (< LOD – .493) 3.86 (2.76 – 5.25) 60.7 (37.5 – 117) 298

Females

Total, 6 years and older 6.27 (5.53 – 7.11) .400 (< LOD – .428) 5.31 (4.37 – 6.35) 141 (108 – 183) 1,066

6–11 years 8.31 (5.47 – 12.6) .803† (< LOD – 1.05) 6.95 (4.34 – 11.5) 132† (75.9 – 259) 94

12–19 years 4.99 (3.73 – 6.67) .347 (< LOD – .484) 4.27 (3.11 – 5.86) 74.7 (47.4 – 131) 187

20–39 years 5.12 (3.67 – 7.15) .359 (.304 – .418) 4.61 (3.37 – 6.48) 103 (66.8 – 197) 271

40–59 years 7.01 (5.37 – 9.15) < LOD 5.48 (3.20 – 7.60) 194 (157 – 323) 218

60 years and older 6.86 (5.44 – 8.66) .484 (< LOD – .719) 5.96 (4.28 – 7.84) 104 (73.9 – 167) 296

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 
412 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.8.b. Urinary O-desmethylangolensin (creatinine corrected): 

Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 4.03 (2.97 – 5.45) <LOD 4.44 (3.11 – 6.27) 165 (143 – 220) 2,271

 2001–2002 3.83 (3.32 – 4.42) <LOD 3.23 (2.56 – 4.12) 281 (157 – 433) 2,794

 2003–2004 4.58 (4.19 – 5.01) <LOD 4.09 (3.55 – 4.58) 201 (185 – 271) 2,581

 2005–2006 4.59 (4.04 – 5.21) <LOD 3.66 (3.12 – 4.41) 211 (182 – 326) 2,528

Age group

6–11 years

 1999–2000 6.00 (4.04 – 8.91) <LOD 7.13 (4.26 – 16.0) 172 (98.0 – 264) 287

 2001–2002 7.03 (5.05 – 9.77) <LOD 6.47 (4.28 – 11.4) 302 (155 – 468) 396

 2003–2004 6.73 (4.55 – 9.97) .389 (<LOD – .743) 5.92 (4.10 – 8.22) 146 (88.9 – 382) 341

 2005–2006 7.93 (5.73 – 11.0) <LOD 7.15 (3.86 – 11.3) 340 (253 – 495) 351

12–19 years

 1999–2000 4.13 (2.33 – 7.35) <LOD 5.68 (2.94 – 11.0) 117 (77.3 – 337) 667

 2001–2002 4.57 (3.44 – 6.07) <LOD 3.86 (2.87 – 5.32) 249 (134 – 331) 744

 2003–2004 4.76 (3.71 – 6.11) <LOD 4.25 (3.22 – 6.13) 182 (119 – 269) 729

 2005–2006 6.30 (4.89 – 8.13) .274 (<LOD – .304) 5.67 (3.60 – 8.37) 251 (127 – 705) 693

20–39 years

 1999–2000 3.18 (2.13 – 4.76) <LOD 3.53 (2.09 – 5.26) 226 (165 – 272) 481

 2001–2002 2.72 (2.10 – 3.51) <LOD 2.06 (1.55 – 2.97) 152 (99.5 – 442) 604

 2003–2004 3.55 (2.86 – 4.40) <LOD 2.98 (2.24 – 3.75) 214 (114 – 434) 546

 2005–2006 3.47 (2.84 – 4.25) <LOD 3.22 (2.11 – 4.37) 166 (136 – 207) 583

40–59 years

 1999–2000 4.26 (3.27 – 5.56) <LOD 3.57 (2.42 – 6.26) 156 (133 – 261) 365

 2001–2002 5.04 (3.50 – 7.26) <LOD 4.39 (2.65 – 7.23) 473 (212 – 885) 531

 2003–2004 4.93 (4.19 – 5.80) <LOD 4.29 (3.06 – 6.30) 227 (190 – 612) 450

 2005–2006 4.09 (3.19 – 5.24) <LOD 3.01 (2.16 – 4.19) 259 (189 – 800) 449

60 years and older

 1999–2000 4.66 (3.13 – 6.94) <LOD 6.37 (3.15 – 11.3) 104 (81.6 – 172) 471

 2001–2002 2.75 (2.14 – 3.52) <LOD 1.86 (1.30 – 2.79) 150 (78.7 – 449) 519

 2003–2004 4.93 (3.88 – 6.28) <LOD 4.37 (3.20 – 6.17) 239 (136 – 418) 515

 2005–2006 5.42 (4.19 – 7.02) <LOD 4.31 (2.90 – 7.08) 244 (111 – 754) 452

Gender

Males

 1999–2000 3.95 (2.79 – 5.58) <LOD 4.50 (2.96 – 6.47) 209 (130 – 265) 1,087

 2001–2002 3.10 (2.48 – 3.86) <LOD 2.87 (2.00 – 3.89) 152 (101 – 334) 1,375

 2003–2004 3.83 (3.10 – 4.73) <LOD 3.33 (2.45 – 4.35) 193 (128 – 255) 1,240

 2005–2006 3.97 (3.33 – 4.72) <LOD 3.48 (2.75 – 4.33) 165 (144 – 230) 1,252

Females

 1999–2000 4.10 (3.00 – 5.60) <LOD 4.17 (3.10 – 6.33) 155 (119 – 341) 1,184

 2001–2002 4.68 (3.87 – 5.68) <LOD 3.74 (2.78 – 4.87) 398 (199 – 741) 1,419

 2003–2004 5.45 (4.71 – 6.30) <LOD 4.81 (4.08 – 5.89) 243 (194 – 318) 1,341

 2005–2006 5.27 (4.56 – 6.09) <LOD 3.98 (3.07 – 5.49) 323 (201 – 683) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 2.19 (1.49 – 3.24) <LOD 1.87 (1.16 – 3.04) 135 (96.7 – 290) 721

 2001–2002 2.30 (1.48 – 3.57) <LOD 1.45 (.769 – 3.15) 107 (59.9 – 303) 679

 2003–2004 2.30 (1.68 – 3.15) <LOD 1.65 (.847 – 3.02) 125 (89.4 – 171) 652

 2005–2006 2.75 (1.92 – 3.93) <LOD 1.68 (1.06 – 2.91) 134 (74.9 – 204) 634

Non-Hispanic Blacks

 1999–2000 3.65 (2.92 – 4.57) <LOD 5.21 (3.70 – 6.74) 117 (83.6 – 283) 527

 2001–2002 3.75 (2.75 – 5.11) <LOD 3.54 (2.13 – 5.48) 217 (102 – 371) 692

 2003–2004 3.90 (3.02 – 5.04) <LOD 3.13 (1.94 – 5.59) 146 (127 – 231) 680

 2005–2006 4.09 (3.13 – 5.34) <LOD 4.20 (2.48 – 5.69) 207 (113 – 454) 662

Non-Hispanic Whites

 1999–2000 4.48 (3.11 – 6.47) <LOD 4.72 (2.91 – 7.48) 178 (148 – 227) 810

 2001–2002 4.08 (3.41 – 4.88) <LOD 3.51 (2.46 – 4.57) 300 (158 – 505) 1,211

 2003–2004 5.18 (4.71 – 5.70) <LOD 4.58 (4.15 – 5.31) 225 (189 – 308) 1,061

 2005–2006 4.96 (4.33 – 5.69) <LOD 3.96 (3.28 – 4.67) 227 (184 – 333) 1,039

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
50th Percentile 95th Percentile 400 

200 

0 

20 

15 

10 

5 

0 

800 

600 

j 

j 

j j 

j 

j 

j 

j 

j 

j 

j 

j 

j 

j 

j j j 

j 

j j j 

j 

j 

j 

j j j j j 

j 

j 

j j 

j 

j j 

j 

j 

j j 

j j j 

j 

j 

j j

j 

j 

j 

j j 

j 

j j j j j 

j 

j 

j j j j 

j 

j j 

j j 

j 

j j 

0 

200 

400 

600 

800 

1000 

5th Percentile 

Total 

(6+y) 

99−0001−0203−0405−06 

3−5y 

99−0001−0203−0405−06 

6−11y 

99−0001−0203−0405−06 

12−19y 99−00 01−02 03−04

05−06 

20+y 

99−0001−0203−0405−06 

Males 

99−0001−0203−0405−06 

Females 99−00 01−02 03−04

05−06 

MA 

99−0001−0203−0405−06 

NHB 

99−0001−0203−0405−06 

NHW 

99−0001−0203−0405−06 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

Figure 4.8.b. Urinary O−desmethylangolensin (creatinine corrected): 

Concentrations by survey cycle 

Selected percentiles in μg/g creatinine (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006

4. Isoflavones and Lignans 413
414

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.9.a.1. Urinary enterodiol: Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 38.6 (35.8 – 41.6) .745 (.399 – 1.29) 2.48 (1.79 – 3.01) 43.9 (41.1 – 47.2) 377 (335 – 414) 579 (496 – 683) 5,122Age group6–11 years 37.4 (32.2 – 43.3) 2.24 (.856 – 4.39) 5.43 (2.74 – 6.96) 40.2 (35.8 – 45.4) 265 (199 – 357) 387 (335 – 558) 692

12–19 years 42.0 (38.3 – 46.1) 2.23 (.927 – 3.06) 5.16 (2.97 – 6.05) 44.2 (39.5 – 50.3) 295 (267 – 354) 462 (374 – 656) 1,422

20–39 years 39.2 (34.7 – 44.2) .763 (.392 – 1.50) 2.70 (1.49 – 3.87) 43.7 (39.7 – 49.9) 365 (314 – 494) 651 (493 – 1,350) 1,137

40–59 years 37.2 (31.3 – 44.1) < LOD 1.72 (.528 – 2.44) 44.8 (37.6 – 51.6) 423 (330 – 512) 658 (462 – 1,250) 901

60 years and older 38.5 (34.3 – 43.2) .478 (< LOD – 1.61) 2.42 (1.28 – 3.37) 44.9 (38.9 – 52.6) 362 (301 – 475) 620 (442 – 1,140) 970

GenderMales 40.1 (35.9 – 44.7) .697 (< LOD – 1.29) 2.49 (1.47 – 3.72) 45.9 (41.2 – 49.2) 382 (308 – 453) 585 (457 – 1,080) 2,496

Females 37.2 (33.7 – 41.1) .813 (< LOD – 1.60) 2.44 (1.59 – 3.02) 42.3 (39.6 – 45.9) 356 (307 – 446) 561 (464 – 712) 2,626

Race/ethnicityMexican Americans 35.6 (31.2 – 40.5) .899 (< LOD – 1.78) 2.41 (1.70 – 2.94) 39.9 (35.5 – 44.6) 359 (287 – 434) 457 (392 – 890) 1,287

Non-Hispanic Blacks 37.4 (33.8 – 41.3) 1.02 (< LOD – 1.65) 2.90 (2.15 – 3.51) 43.1 (38.4 – 47.4) 275 (249 – 348) 438 (372 – 517) 1,343

Non-Hispanic Whites 38.7 (34.9 – 42.8) .640 (< LOD – 1.36) 2.44 (1.49 – 3.41) 44.2 (40.2 – 49.6) 367 (310 – 423) 575 (480 – 701) 2,108

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
6−11 12−19 20−39 40−59 60+ 

0 20 40 60 80 

Urinary enterodiol (μg/L) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

80 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 4.9.a. Urinary enterodiol: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary enterodiol Urinary enterodiol (μg/L) (μg/L) 0 20 40 60 80 0 20 40 60 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

4. Isoflavones and Lignans 415
416 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.9.a.2. Urinary enterodiol: Total population

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 

years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 38.6 (35.8 – 41.6) 5.86 (4.78 – 6.69) 43.9 (41.1 – 47.2) 243 (231 – 260) 5,122

6–11 years 37.4 (32.2 – 43.3) 8.10 (6.48 – 9.64) 40.2 (35.8 – 45.4) 150 (126 – 204) 692

12–19 years 42.0 (38.3 – 46.1) 8.12 (6.76 – 9.75) 44.2 (39.5 – 50.3) 192 (168 – 229) 1,422

20–39 years 39.2 (34.7 – 44.2) 5.37 (4.41 – 6.89) 43.7 (39.7 – 49.9) 237 (216 – 267) 1,137

40–59 years 37.2 (31.3 – 44.1) 3.96 (2.46 – 6.11) 44.8 (37.6 – 51.6) 266 (250 – 284) 901

60 years and older 38.5 (34.3 – 43.2) 5.80 (3.81 – 6.96) 44.9 (38.9 – 52.6) 256 (219 – 280) 970

Males

Total, 6 years and older 40.1 (35.9 – 44.7) 6.59 (5.15 – 7.44) 45.9 (41.2 – 49.2) 255 (228 – 269) 2,496

6–11 years 38.4 (31.1 – 47.5) 8.71 (5.91 – 13.1) 39.7 (34.8 – 47.9) 144 (119 – 267) 340

12–19 years 42.6 (37.3 – 48.7) 8.25 (6.58 – 10.2) 48.4 (38.5 – 56.4) 196 (170 – 250) 728

20–39 years 38.9 (31.6 – 47.9) 5.61 (3.56 – 7.73) 43.8 (36.7 – 50.8) 236 (202 – 293) 499

40–59 years 40.8 (32.8 – 50.7) 5.03 (2.54 – 8.69) 47.7 (38.3 – 54.0) 279 (261 – 332) 451

60 years and older 40.1 (33.1 – 48.7) 6.13 (4.41 – 7.48) 50.2 (41.1 – 56.3) 256 (210 – 307) 478

Females

Total, 6 years and older 37.2 (33.7 – 41.1) 5.09 (4.12 – 6.40) 42.3 (39.6 – 45.9) 237 (211 – 262) 2,626

6–11 years 36.3 (30.5 – 43.1) 7.66 (5.98 – 9.58) 40.7 (32.9 – 49.6) 157 (120 – 220) 352

12–19 years 41.4 (36.8 – 46.6) 8.00 (5.89 – 10.0) 41.9 (37.7 – 46.4) 181 (155 – 221) 694

20–39 years 39.4 (34.2 – 45.5) 4.90 (4.25 – 6.75) 43.7 (39.8 – 53.3) 243 (209 – 301) 638

40–59 years 34.1 (27.1 – 42.9) 3.31 (1.49 – 5.80) 41.6 (34.4 – 51.5) 244 (205 – 278) 450

60 years and older 37.3 (31.9 – 43.6) 4.59 (2.99 – 6.98) 42.3 (33.7 – 51.7) 255 (204 – 302) 492

Table 4.9.a.3. Urinary enterodiol: Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/L) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 35.6 (31.2 – 40.5) 4.89 (4.22 – 5.85) 39.9 (35.5 – 44.6) 227 (182 – 294) 1,287

6–11 years 27.4 (21.8 – 34.5) 2.79 (1.96 – 5.28) 33.0 (24.6 – 40.2) 166 (130 – 245) 231

12–19 years 35.6 (30.9 – 41.1) 5.80 (3.99 – 8.54) 42.0 (34.8 – 48.2) 178 (141 – 203) 445

20–39 years 38.2 (29.5 – 49.6) 5.52 (3.85 – 7.09) 41.8 (31.6 – 52.4) 245 (183 – 438) 282

40–59 years 39.5 (28.6 – 54.5) 5.19 (1.73 – 11.5) 41.1 (31.9 – 53.6) 272 (192 – 385) 157

60 years and older 28.4 (22.0 – 36.8) 3.31 (1.54 – 5.74) 35.1 (22.0 – 49.2) 165 (111 – 340) 172

Males

Total, 6 years and older 34.9 (28.8 – 42.2) 4.34 (3.14 – 6.04) 43.3 (35.6 – 49.9) 206 (165 – 288) 625

6–11 years 28.1 (19.2 – 40.9) 2.97 (.785 – 7.94) 34.7 (22.8 – 48.2) 135 (92.4 – 185) 112

12–19 years 34.5 (26.5 – 45.0) 4.74 (2.34 – 9.50) 41.5 (30.3 – 52.8) 189 (126 – 266) 228

20–39 years 33.4 (22.2 – 50.1) 4.48 (.741 – 7.36) 42.6 (24.6 – 55.0) 204 (135 – 414) 117

40–59 years 42.7 (28.2 – 64.6) 4.04† (< LOD – 14.4) 51.2 (32.8 – 64.8) 256† (170 – 404) 85

60 years and older 40.6 (25.5 – 64.6) 4.67† (2.24 – 6.33) 42.7 (19.6 – 89.1) 222† (160 – 2,850) 83

Females

Total, 6 years and older 36.3 (32.0 – 41.2) 5.48 (4.68 – 6.52) 37.1 (31.4 – 42.1) 238 (185 – 325) 662

6–11 years 26.7 (20.1 – 35.4) 2.49 (1.71 – 4.92) 30.5 (20.3 – 43.1) 196 (136 – 335) 119

12–19 years 36.9 (32.0 – 42.4) 7.51 (5.16 – 9.36) 42.2 (35.0 – 53.7) 162 (118 – 195) 217

20–39 years 44.9 (32.5 – 62.1) 6.26 (3.86 – 9.31) 41.4 (27.8 – 61.5) 306 (193 – 937) 165

40–59 years 36.3 (22.5 – 58.5) 5.97† (< LOD – 11.6) 31.7 (19.0 – 59.2) 274† (189 – 476) 72

60 years and older 21.3 (15.0 – 30.3) 2.49† (.826 – 4.86) 28.1 (16.1 – 45.6) 115† (67.5 – 254) 89

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 417

Table 4.9.a.4. Urinary enterodiol: Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 37.4 (33.8 – 41.3) 6.94 (5.78 – 8.13) 43.1 (38.4 – 47.4) 202 (164 – 241) 1,343

6–11 years 39.0 (32.6 – 46.6) 8.75 (7.57 – 10.9) 38.5 (32.6 – 47.4) 144 (113 – 222) 207

12–19 years 40.4 (35.8 – 45.5) 7.82 (6.32 – 10.2) 45.9 (40.2 – 53.4) 203 (158 – 252) 496

20–39 years 34.4 (28.9 – 40.8) 4.70 (2.73 – 9.26) 43.1 (30.9 – 49.3) 182 (138 – 247) 249

40–59 years 38.3 (31.0 – 47.3) 6.45 (3.55 – 9.50) 42.9 (34.8 – 56.0) 229 (159 – 306) 231

60 years and older 38.6 (29.7 – 50.2) 5.01 (2.37 – 11.3) 41.5 (33.1 – 54.2) 213 (143 – 308) 160

Males

Total, 6 years and older 35.8 (31.0 – 41.4) 7.23 (5.38 – 9.93) 41.2 (37.1 – 44.8) 199 (145 – 256) 661

6–11 years 36.7 (30.6 – 44.0) 8.71† (5.22 – 12.3) 37.6 (32.5 – 45.6) 130† (93.9 – 271) 99

12–19 years 41.5 (35.7 – 48.2) 8.60 (6.42 – 10.6) 46.0 (36.3 – 56.7) 220 (161 – 274) 258

20–39 years 34.8 (25.0 – 48.5) 9.49 (1.28 – 12.7) 42.3 (28.4 – 49.0) 194 (117 – 649) 116

40–59 years 34.2 (25.5 – 45.8) 6.41 (.424 – 11.2) 40.1 (31.0 – 51.0) 181 (103 – 339) 114

60 years and older 33.8 (22.6 – 50.5) 3.16† (< LOD – 9.91) 38.8 (22.4 – 60.4) 235† (178 – 506) 74

Females

Total, 6 years and older 38.8 (33.8 – 44.5) 6.71 (4.70 – 8.09) 45.3 (36.5 – 52.9) 209 (159 – 246) 682

6–11 years 41.5 (28.5 – 60.3) 8.80† (5.57 – 12.1) 38.5 (25.1 – 63.3) 162† (105 – 734) 108

12–19 years 39.3 (34.1 – 45.3) 7.36 (4.62 – 10.8) 45.8 (38.4 – 54.9) 181 (148 – 227) 238

20–39 years 34.0 (25.1 – 45.9) 4.44 (1.93 – 7.72) 43.6 (29.2 – 57.8) 163 (129 – 250) 133

40–59 years 42.1 (31.0 – 57.1) 6.38 (3.20 – 9.27) 47.1 (30.4 – 65.8) 241 (167 – 440) 117

60 years and older 42.0 (31.7 – 55.6) 8.15† (2.80 – 14.6) 44.5 (31.8 – 61.6) 173† (120 – 404) 86

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.9.a.5. Urinary enterodiol: Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic whites in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 38.7 (34.9 – 42.8) 5.87 (4.61 – 6.90) 44.2 (40.2 – 49.6) 244 (228 – 264) 2,108

6–11 years 39.3 (30.9 – 50.1) 8.74 (6.52 – 13.2) 40.4 (34.8 – 48.0) 139 (115 – 232) 193

12–19 years 42.1 (36.3 – 48.8) 8.80 (6.91 – 10.6) 42.8 (36.5 – 54.4) 176 (154 – 230) 378

20–39 years 40.0 (33.4 – 47.9) 5.42 (4.12 – 7.14) 43.8 (36.4 – 55.7) 238 (207 – 296) 494

40–59 years 36.3 (29.2 – 45.1) 3.71 (2.29 – 6.10) 45.2 (35.6 – 54.8) 264 (243 – 281) 448

60 years and older 38.8 (34.2 – 43.9) 5.91 (3.70 – 7.29) 46.0 (38.9 – 56.1) 258 (213 – 280) 595

Males

Total, 6 years and older 41.1 (35.5 – 47.6) 6.75 (5.23 – 8.72) 46.4 (40.6 – 52.7) 259 (222 – 275) 1,035

6–11 years 40.8 (29.6 – 56.1) 9.08† (4.58 – 17.3) 39.9 (32.8 – 49.3) 129† (109 – 356) 99

12–19 years 42.5 (35.6 – 50.7) 9.11 (6.18 – 11.8) 48.2 (36.1 – 57.6) 176 (148 – 252) 191

20–39 years 40.6 (30.3 – 54.3) 5.50 (3.34 – 9.65) 43.8 (33.6 – 59.1) 238 (184 – 394) 217

40–59 years 42.2 (31.6 – 56.5) 5.30 (2.37 – 10.1) 48.1 (36.7 – 58.2) 280 (259 – 415) 229

60 years and older 39.4 (31.3 – 49.4) 6.58 (4.37 – 8.47) 50.3 (40.5 – 56.9) 246 (182 – 286) 299

Females

Total, 6 years and older 36.4 (31.6 – 41.9) 4.79 (3.03 – 6.57) 42.3 (38.0 – 49.9) 240 (201 – 273) 1,073

6–11 years 37.7 (28.8 – 49.2) 7.98† (2.17 – 11.7) 41.0 (29.3 – 54.4) 155† (94.9 – 369) 94

12–19 years 41.6 (33.6 – 51.6) 8.15 (5.01 – 13.4) 40.1 (34.9 – 51.0) 174 (131 – 278) 187

20–39 years 39.4 (31.4 – 49.4) 4.87 (3.72 – 7.60) 46.0 (34.2 – 56.9) 236 (183 – 332) 277

40–59 years 31.2 (23.5 – 41.4) 2.52 (.780 – 5.15) 40.5 (31.0 – 55.4) 242 (189 – 276) 219

60 years and older 38.3 (32.0 – 45.8) 4.66 (2.91 – 7.14) 44.6 (33.4 – 58.2) 263 (207 – 309) 296

† Estimate is subject to greater uncertainty due to small cell size. 
418 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.9.b. Urinary enterodiol: Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 26.6 (21.9 – 32.3) < LOD 33.9 (29.5 – 38.7) 263 (219 – 338) 2,527

 2001–2002 35.7 (32.5 – 39.3) 2.10 (< LOD – 3.07) 39.3 (36.4 – 43.1) 253 (225 – 307) 2,794

 2003–2004 39.5 (36.1 – 43.3) 2.45 (1.76 – 2.91) 44.8 (40.7 – 50.3) 367 (318 – 424) 2,594

 2005–2006 37.7 (33.2 – 42.9) 2.47 (.884 – 3.82) 42.4 (39.3 – 47.2) 378 (316 – 447) 2,528

Age group

6–11 years

 1999–2000 26.5 (17.1 – 41.0) < LOD 29.3 (21.2 – 43.4) 272 (203 – 477) 327

 2001–2002 33.6 (29.8 – 37.8) 3.40 (1.90 – 5.06) 35.5 (29.4 – 43.5) 202 (170 – 333) 396

 2003–2004 42.0 (34.5 – 51.1) 6.62 (2.92 – 8.30) 42.0 (34.6 – 49.1) 311 (230 – 523) 341

 2005–2006 33.2 (26.1 – 42.3) 2.86 (1.71 – 6.66) 38.5 (34.7 – 44.3) 178 (136 – 377) 351

12–19 years

 1999–2000 29.8 (23.8 – 37.2) < LOD 34.0 (27.8 – 42.0) 252 (193 – 357) 744

 2001–2002 35.3 (30.5 – 40.9) 3.30 (2.02 – 5.23) 37.6 (34.8 – 42.9) 235 (172 – 344) 744

 2003–2004 45.1 (39.4 – 51.6) 5.28 (3.63 – 6.65) 46.2 (38.8 – 56.8) 324 (276 – 416) 729

 2005–2006 39.1 (34.0 – 45.0) 4.19 (1.72 – 6.24) 41.0 (36.8 – 46.4) 264 (232 – 367) 693

20–39 years

 1999–2000 27.4 (22.1 – 34.1) < LOD 36.0 (29.9 – 41.3) 230 (177 – 401) 535

 2001–2002 35.3 (29.5 – 42.3) < LOD 42.5 (36.6 – 47.6) 244 (213 – 371) 604

 2003–2004 39.7 (33.2 – 47.5) 2.69 (1.32 – 3.59) 44.5 (37.7 – 53.9) 372 (308 – 654) 554

 2005–2006 38.6 (32.3 – 46.2) 3.01 (1.16 – 4.28) 43.5 (34.5 – 53.8) 352 (289 – 519) 583

40–59 years

 1999–2000 26.1 (21.4 – 31.8) < LOD 34.6 (28.9 – 41.2) 280 (249 – 406) 414

 2001–2002 37.3 (29.2 – 47.7) < LOD 40.5 (34.5 – 50.9) 289 (232 – 488) 531

 2003–2004 35.3 (28.6 – 43.6) 1.36 (< LOD – 2.16) 42.6 (36.3 – 50.6) 418 (283 – 712) 452

 2005–2006 39.0 (29.4 – 51.8) 2.30 (< LOD – 4.32) 45.9 (34.1 – 59.0) 445 (287 – 651) 449

60 years and older

 1999–2000 23.7 (18.8 – 30.0) < LOD 29.7 (21.9 – 37.4) 264 (167 – 479) 507

 2001–2002 35.4 (30.0 – 41.8) 2.87 (1.55 – 4.49) 36.5 (30.2 – 46.0) 224 (195 – 364) 519

 2003–2004 41.7 (36.7 – 47.4) 2.84 (1.82 – 4.35) 50.8 (43.2 – 58.3) 309 (265 – 615) 518

 2005–2006 35.6 (29.0 – 43.8) 1.66 (< LOD – 3.05) 39.9 (31.1 – 51.8) 415 (322 – 614) 452

Gender

Males

 1999–2000 25.3 (19.5 – 32.7) < LOD 33.0 (28.0 – 37.9) 258 (179 – 324) 1,206

 2001–2002 35.2 (31.8 – 39.1) < LOD 40.4 (36.8 – 44.2) 263 (225 – 351) 1,375

 2003–2004 39.7 (36.2 – 43.6) 2.43 (.998 – 3.97) 45.1 (40.6 – 50.6) 360 (275 – 515) 1,244

 2005–2006 40.4 (32.8 – 49.8) 2.64 (.957 – 4.13) 46.1 (39.1 – 52.0) 413 (291 – 544) 1,252

Females

 1999–2000 27.9 (23.4 – 33.3) < LOD 36.0 (29.9 – 40.2) 280 (228 – 397) 1,321

 2001–2002 36.2 (32.2 – 40.7) 3.20 (< LOD – 4.75) 38.5 (35.3 – 43.4) 246 (222 – 286) 1,419

 2003–2004 39.3 (33.8 – 45.5) 2.60 (1.33 – 3.36) 44.8 (38.5 – 52.7) 396 (313 – 485) 1,350

 2005–2006 35.4 (30.3 – 41.2) 2.43 (.524 – 3.72) 41.0 (35.7 – 45.3) 338 (272 – 477) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 21.7 (19.5 – 24.1) < LOD 27.9 (24.6 – 34.6) 212 (171 – 258) 791

 2001–2002 30.5 (25.7 – 36.3) 1.62 (< LOD – 2.79) 33.8 (29.0 – 39.1) 240 (198 – 304) 679

 2003–2004 33.1 (26.4 – 41.6) 1.90 (< LOD – 3.68) 38.5 (31.7 – 47.1) 298 (201 – 4,230) 653

 2005–2006 38.1 (32.2 – 45.1) 2.60 (1.91 – 3.84) 40.5 (35.4 – 47.5) 382 (295 – 514) 634

Non-Hispanic Blacks

 1999–2000 25.7 (21.5 – 30.6) < LOD 31.2 (24.4 – 35.9) 266 (219 – 356) 597

 2001–2002 35.1 (28.8 – 42.8) 2.08 (< LOD – 3.42) 38.8 (33.3 – 49.8) 222 (178 – 386) 692

 2003–2004 40.3 (34.7 – 46.8) 3.23 (1.48 – 4.64) 47.2 (40.7 – 54.4) 284 (244 – 442) 681

 2005–2006 34.7 (30.1 – 40.1) 2.73 (2.01 – 3.30) 38.4 (33.3 – 45.1) 268 (248 – 382) 662

Non-Hispanic Whites

 1999–2000 29.1 (24.2 – 35.1) < LOD 37.5 (31.6 – 43.7) 271 (219 – 401) 899

 2001–2002 35.6 (31.8 – 40.0) 1.82 (< LOD – 3.21) 40.4 (36.5 – 44.7) 254 (219 – 341) 1,211

 2003–2004 40.1 (35.6 – 45.1) 2.64 (1.59 – 3.48) 45.9 (38.9 – 55.3) 368 (305 – 441) 1,069

 2005–2006 37.3 (31.2 – 44.6) 2.36 (.472 – 3.81) 42.6 (37.1 – 49.6) 366 (286 – 456) 1,039

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
5th Percentile 50th Percentile 95th Percentile 

5000 

4000 

3000 

2000 

1000 

0 

60 

50 

40 

30 

20 

10 

8 

6 

4 

2 

0 

j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j 

j 

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j 

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j 

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j 

j 

j j 

j 

j 

j j 

j 

j 

j 

j 

j 

j 

j 

j 

j 

j 

j 

j j 

j 

j 

j 

j j 

j 

j 

j 

j 

j 

j 

j 

j j j j j j 

j 

j j j 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

Figure 4.9.b. Urinary enterodiol: Concentrations by survey cycle 

Selected percentiles in μg/L (95% confidence intervals), National Health and 


Nutrition Examination Survey, 1999–2006
 

4. Isoflavones and Lignans 419
420

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.10.a.1. Urinary enterodiol (creatinine corrected): Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 36.9 (34.3 – 39.7) .909 (.427 – 1.35) 2.69 (1.93 – 3.70) 41.1 (38.2 – 44.1) 309 (283 – 360) 501 (440 – 716) 5,122Age group6–11 years 40.5 (35.1 – 46.7) 3.41 (1.25 – 4.93) 6.16 (3.95 – 7.30) 43.6 (38.1 – 48.1) 216 (198 – 311) 367 (267 – 589) 692

12–19 years 31.3 (28.7 – 34.1) 1.87 (.883 – 2.78) 3.58 (2.79 – 4.68) 33.6 (31.9 – 36.1) 186 (163 – 232) 278 (220 – 542) 1,422

20–39 years 33.4 (29.3 – 38.1) .793 (.250 – 1.49) 2.29 (1.52 – 2.99) 34.9 (31.6 – 43.0) 301 (244 – 400) 492 (366 – 808) 1,137

40–59 years 37.6 (31.8 – 44.5) < LOD 1.75 (.889 – 3.41) 42.7 (36.6 – 50.2) 376 (286 – 491) 686 (438 – 1,530) 901

60 years and older 45.1 (39.9 – 50.9) .610 (< LOD – 1.82) 4.15 (1.05 – 5.93) 51.0 (47.1 – 55.6) 386 (290 – 539) 556 (469 – 1,500) 970

GenderMales 31.8 (28.5 – 35.5) .588 (< LOD – 1.30) 2.25 (1.31 – 3.67) 34.6 (32.0 – 38.0) 280 (233 – 338) 445 (331 – 789) 2,496

Females 42.5 (38.9 – 46.4) .975 (< LOD – 1.86) 2.95 (2.22 – 4.19) 48.4 (45.0 – 54.6) 375 (296 – 432) 563 (445 – 852) 2,626

Race/ethnicityMexican Americans 32.1 (27.9 – 36.9) 1.20 (< LOD – 1.87) 2.67 (1.62 – 3.47) 35.1 (30.5 – 39.3) 305 (239 – 375) 431 (337 – 876) 1,287

Non-Hispanic Blacks 26.3 (23.5 – 29.3) .859 (< LOD – 1.10) 2.60 (1.56 – 3.18) 27.8 (24.9 – 31.4) 196 (165 – 218) 276 (224 – 353) 1,343

Non-Hispanic Whites 39.4 (35.5 – 43.6) .849 (< LOD – 1.40) 2.87 (1.86 – 4.12) 45.4 (40.8 – 49.6) 315 (287 – 375) 508 (438 – 736) 2,108

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
6−11 12−19 20−39 40−59 60+ 

0 20 40 60 80 

Urinary enterodiol (μg/g creatinine) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 4.10.a. Urinary enterodiol (creatinine corrected): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary enterodiol Urinary enterodiol (μg/g creatinine) (μg/g creatinine) 0 20 40 60 80 0 20 40 60 80 

Non−Hispanic Blacks 

6−11 12−19 20−39 40−59 60+ 

Females 

6−11 12−19 20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

6−11 12−19 20−39 40−59 60+ 

Males 

6−11 12−19 20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

4. Isoflavones and Lignans 421
422 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.10.a.2. Urinary enterodiol (creatinine corrected): Total population

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 36.9 (34.3 – 39.7) 6.26 (5.53 – 7.25) 41.1 (38.2 – 44.1) 202 (185 – 213) 5,122

6–11 years 40.5 (35.1 – 46.7) 8.85 (6.90 – 12.2) 43.6 (38.1 – 48.1) 166 (134 – 201) 692

12–19 years 31.3 (28.7 – 34.1) 6.90 (5.55 – 8.00) 33.6 (31.9 – 36.1) 130 (117 – 154) 1,422

20–39 years 33.4 (29.3 – 38.1) 5.04 (4.01 – 6.33) 34.9 (31.6 – 43.0) 185 (156 – 230) 1,137

40–59 years 37.6 (31.8 – 44.5) 5.64 (3.76 – 7.61) 42.7 (36.6 – 50.2) 217 (201 – 275) 901

60 years and older 45.1 (39.9 – 50.9) 7.91 (6.45 – 9.98) 51.0 (47.1 – 55.6) 228 (198 – 290) 970

Males

Total, 6 years and older 31.8 (28.5 – 35.5) 5.68 (4.73 – 6.43) 34.6 (32.0 – 38.0) 176 (150 – 210) 2,496

6–11 years 38.5 (31.7 – 46.9) 8.54 (6.17 – 13.0) 38.3 (33.3 – 46.1) 144 (117 – 205) 340

12–19 years 28.9 (25.7 – 32.5) 5.59 (5.19 – 7.40) 32.6 (28.5 – 34.9) 123 (113 – 134) 728

20–39 years 28.3 (23.0 – 34.9) 4.69 (3.28 – 5.94) 29.9 (25.6 – 35.5) 152 (128 – 253) 499

40–59 years 32.3 (25.6 – 40.8) 5.53 (3.19 – 7.12) 33.7 (28.4 – 43.1) 207 (158 – 305) 451

60 years and older 36.9 (30.3 – 45.1) 6.29 (4.32 – 8.00) 43.8 (38.4 – 51.5) 204 (169 – 240) 478

Females

Total, 6 years and older 42.5 (38.9 – 46.4) 7.53 (5.73 – 8.57) 48.4 (45.0 – 54.6) 210 (198 – 234) 2,626

6–11 years 42.7 (35.9 – 50.8) 9.12 (6.71 – 12.6) 48.1 (40.3 – 57.8) 177 (140 – 218) 352

12–19 years 34.1 (30.1 – 38.5) 8.29 (4.44 – 9.54) 36.0 (32.2 – 39.7) 144 (119 – 165) 694

20–39 years 39.2 (33.9 – 45.5) 5.48 (3.87 – 7.78) 46.3 (35.7 – 57.4) 203 (165 – 243) 638

40–59 years 43.4 (35.2 – 53.6) 5.72 (2.41 – 9.51) 52.6 (42.7 – 63.1) 231 (207 – 301) 450

60 years and older 52.8 (46.0 – 60.6) 9.89 (7.70 – 11.6) 57.4 (50.4 – 65.3) 249 (201 – 407) 492

Table 4.10.a.3. Urinary enterodiol (creatinine corrected): Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for Mexican Americans in 

the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 32.1 (27.9 – 36.9) 4.54 (3.80 – 6.35) 35.1 (30.5 – 39.3) 185 (145 – 226) 1,287

6–11 years 34.4 (27.9 – 42.4) 5.18 (3.71 – 6.71) 37.2 (33.9 – 44.9) 178 (135 – 226) 231

12–19 years 27.5 (23.8 – 31.9) 4.55 (3.18 – 7.34) 33.6 (28.0 – 37.6) 123 (96.1 – 147) 445

20–39 years 30.9 (23.4 – 40.7) 4.02 (2.24 – 6.39) 31.1 (27.4 – 39.6) 203 (126 – 343) 282

40–59 years 36.1 (27.6 – 47.3) 5.14 (2.37 – 11.4) 35.2 (27.5 – 43.1) 234 (172 – 328) 157

60 years and older 35.1 (29.0 – 42.6) 5.53 (5.00 – 7.33) 40.9 (32.0 – 50.3) 171 (127 – 206) 172

Males

Total, 6 years and older 27.6 (22.7 – 33.4) 3.88 (2.69 – 5.22) 33.1 (27.7 – 39.2) 145 (125 – 188) 625

6–11 years 33.6 (24.5 – 46.3) 5.54 (1.57 – 10.7) 39.3 (30.6 – 49.5) 136 (109 – 223) 112

12–19 years 25.0 (19.6 – 31.9) 3.94 (1.46 – 7.15) 31.8 (22.5 – 38.9) 128 (88.0 – 179) 228

20–39 years 24.2 (16.6 – 35.3) 3.11 (.554 – 5.48) 27.9 (20.7 – 38.8) 126 (93.7 – 316) 117

40–59 years 31.3 (21.1 – 46.5) 4.37† (< LOD – 9.03) 36.9 (24.4 – 56.4) 151† (125 – 326) 85

60 years and older 36.1 (23.6 – 55.3) 5.32† (1.31 – 7.57) 42.1 (24.2 – 74.3) 180† (111 – 3,470) 83

Females

Total, 6 years and older 37.9 (33.8 – 42.5) 6.60 (4.51 – 9.67) 35.9 (33.1 – 40.5) 214 (182 – 310) 662

6–11 years 35.2 (26.6 – 46.6) 5.04 (3.18 – 6.59) 36.4 (28.5 – 45.9) 189 (140 – 434) 119

12–19 years 30.4 (26.0 – 35.7) 6.37 (3.16 – 9.37) 36.5 (29.2 – 40.5) 111 (87.0 – 153) 217

20–39 years 41.1 (30.3 – 55.6) 6.65 (2.66 – 10.7) 34.6 (28.4 – 43.7) 225 (156 – 1,900) 165

40–59 years 42.2 (28.5 – 62.7) 10.9† (< LOD – 15.6) 34.7 (24.5 – 42.5) 322† (224 – 401) 72

60 years and older 34.4 (25.4 – 46.4) 7.20† (1.42 – 12.2) 39.5 (30.7 – 49.7) 134† (114 – 219) 89

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 423

Table 4.10.a.4. Urinary enterodiol (creatinine corrected): Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic blacks 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 26.3 (23.5 – 29.3) 5.31 (4.24 – 6.34) 27.8 (24.9 – 31.4) 125 (110 – 152) 1,343

6–11 years 36.6 (30.6 – 43.8) 9.75 (7.92 – 11.3) 34.5 (25.8 – 45.8) 136 (108 – 215) 207

12–19 years 23.2 (20.8 – 25.8) 4.63 (3.25 – 5.70) 26.0 (23.5 – 29.3) 97.7 (86.3 – 107) 496

20–39 years 21.3 (17.7 – 25.7) 3.72 (2.11 – 6.01) 23.0 (17.8 – 28.7) 114 (101 – 145) 249

40–59 years 27.8 (22.9 – 33.9) 4.81 (3.72 – 6.10) 31.2 (25.2 – 42.5) 138 (98.2 – 207) 231

60 years and older 34.4 (27.2 – 43.5) 6.11 (3.63 – 7.83) 40.0 (25.1 – 53.3) 158 (126 – 211) 160

Males

Total, 6 years and older 20.9 (17.8 – 24.6) 4.17 (3.10 – 5.70) 23.1 (21.0 – 25.9) 103 (84.9 – 141) 661

6–11 years 34.7 (28.7 – 41.9) 9.17† (6.49 – 13.8) 27.8 (23.6 – 42.1) 133† (87.7 – 254) 99

12–19 years 22.2 (19.3 – 25.5) 3.94 (2.80 – 5.30) 25.8 (22.0 – 30.4) 98.2 (78.0 – 114) 258

20–39 years 16.7 (12.1 – 23.1) 3.28 (.958 – 7.92) 15.6 (13.4 – 23.1) 98.0 (48.0 – 228) 116

40–59 years 19.5 (14.7 – 25.9) 3.83 (.303 – 5.78) 24.4 (19.1 – 30.5) 88.7 (62.6 – 143) 114

60 years and older 24.8 (17.4 – 35.3) 2.85† (< LOD – 5.98) 29.4 (16.7 – 46.4) 154† (105 – 375) 74

Females

Total, 6 years and older 31.8 (27.2 – 37.1) 6.96 (4.95 – 7.88) 34.8 (28.3 – 44.5) 145 (124 – 183) 682

6–11 years 38.7 (26.3 – 56.9) 9.48† (5.62 – 11.4) 36.2 (23.8 – 63.6) 138† (104 – 671) 108

12–19 years 24.3 (21.1 – 27.9) 5.67 (2.69 – 8.07) 26.0 (22.5 – 31.5) 97.2 (83.9 – 118) 238

20–39 years 25.8 (18.5 – 36.1) 4.01 (1.38 – 6.49) 28.5 (21.8 – 40.2) 122 (104 – 202) 133

40–59 years 37.3 (27.8 – 50.0) 7.65 (4.05 – 10.2) 45.8 (26.5 – 61.7) 186 (131 – 262) 117

60 years and older 42.4 (32.8 – 54.7) 7.78† (3.31 – 15.1) 42.5 (29.1 – 68.6) 157† (127 – 219) 86

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.10.a.5. Urinary enterodiol (creatinine corrected): Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic whites 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 39.4 (35.5 – 43.6) 6.60 (5.58 – 8.19) 45.4 (40.8 – 49.6) 205 (186 – 224) 2,108

6–11 years 42.6 (34.0 – 53.4) 11.1 (5.34 – 16.8) 46.1 (37.0 – 52.0) 151 (121 – 226) 193

12–19 years 33.0 (28.8 – 37.8) 7.53 (5.66 – 9.35) 34.6 (31.7 – 40.5) 132 (117 – 163) 378

20–39 years 36.9 (30.1 – 45.0) 5.49 (3.01 – 7.72) 42.6 (32.9 – 54.0) 187 (154 – 248) 494

40–59 years 39.0 (31.5 – 48.3) 5.69 (3.16 – 8.27) 46.7 (37.1 – 56.0) 217 (195 – 290) 448

60 years and older 46.2 (40.4 – 52.9) 8.98 (6.44 – 11.1) 52.2 (47.7 – 56.5) 234 (199 – 291) 595

Males

Total, 6 years and older 34.4 (29.6 – 40.0) 6.14 (4.80 – 7.62) 37.5 (32.7 – 42.5) 186 (150 – 238) 1,035

6–11 years 39.5 (29.3 – 53.4) 12.2† (1.42 – 18.9) 38.4 (31.5 – 49.8) 127† (93.3 – 328) 99

12–19 years 30.3 (26.1 – 35.3) 6.16 (5.29 – 8.96) 33.2 (27.5 – 40.5) 123 (111 – 139) 191

20–39 years 32.2 (23.7 – 43.7) 5.54 (2.27 – 8.17) 32.5 (23.0 – 47.3) 185 (128 – 338) 217

40–59 years 35.4 (26.0 – 48.1) 5.70 (2.28 – 9.38) 37.4 (28.6 – 50.0) 213 (158 – 341) 229

60 years and older 36.7 (29.0 – 46.4) 6.56 (2.03 – 10.7) 44.0 (38.4 – 52.2) 195 (164 – 241) 299

Females

Total, 6 years and older 44.9 (39.5 – 51.0) 7.63 (5.36 – 9.36) 55.6 (47.8 – 60.8) 216 (199 – 251) 1,073

6–11 years 46.6 (36.2 – 60.0) 10.2† (4.05 – 15.4) 53.8 (41.4 – 64.6) 171† (131 – 302) 94

12–19 years 36.2 (29.2 – 44.9) 8.91 (4.19 – 10.9) 39.1 (31.4 – 46.2) 151 (117 – 216) 187

20–39 years 42.2 (33.9 – 52.5) 4.89 (2.69 – 8.91) 56.3 (40.0 – 66.8) 203 (159 – 275) 277

40–59 years 43.1 (32.8 – 56.7) 5.49 (1.59 – 9.39) 58.2 (42.5 – 71.1) 217 (204 – 305) 219

60 years and older 55.5 (48.1 – 64.0) 10.2 (7.90 – 12.2) 60.5 (51.3 – 67.3) 291 (203 – 469) 296

† Estimate is subject to greater uncertainty due to small cell size. 
424 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.10.b. Urinary enterodiol (creatinine corrected): Concentrations by 

survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 24.2 (20.3 – 28.9) <LOD 29.9 (25.1 – 34.7) 239 (203 – 320) 2,527

 2001–2002 33.5 (30.7 – 36.7) 2.54 (<LOD – 2.96) 37.6 (33.0 – 42.0) 224 (201 – 249) 2,794

 2003–2004 37.0 (33.6 – 40.7) 2.45 (1.86 – 3.57) 41.7 (38.0 – 45.4) 293 (249 – 376) 2,594

 2005–2006 36.8 (32.7 – 41.4) 2.95 (1.16 – 4.43) 40.9 (36.0 – 46.1) 323 (283 – 421) 2,528

Age group

6–11 years

 1999–2000 27.0 (18.6 – 39.3) <LOD 33.5 (22.1 – 43.6) 278 (199 – 534) 327

 2001–2002 38.1 (32.5 – 44.7) 3.88 (2.45 – 5.14) 39.3 (31.0 – 53.1) 303 (244 – 390) 396

 2003–2004 44.7 (37.4 – 53.5) 6.38 (3.61 – 8.72) 46.5 (38.6 – 58.0) 213 (184 – 414) 341

 2005–2006 36.6 (28.9 – 46.4) 4.69 (1.80 – 7.52) 37.8 (33.0 – 46.5) 221 (186 – 349) 351

12–19 years

 1999–2000 20.1 (16.7 – 24.2) <LOD 24.0 (19.9 – 30.1) 157 (125 – 176) 744

 2001–2002 27.2 (23.3 – 31.8) 2.75 (1.30 – 4.91) 28.7 (25.0 – 34.8) 150 (116 – 316) 744

 2003–2004 33.8 (30.3 – 37.7) 4.69 (2.38 – 5.62) 34.7 (33.3 – 38.2) 216 (155 – 344) 729

 2005–2006 29.0 (25.2 – 33.3) 3.01 (2.13 – 3.60) 31.1 (28.0 – 36.1) 165 (160 – 214) 693

20–39 years

 1999–2000 21.7 (17.1 – 27.6) <LOD 26.4 (21.4 – 32.4) 232 (149 – 371) 535

 2001–2002 28.5 (23.7 – 34.3) <LOD 30.2 (25.2 – 39.4) 187 (156 – 277) 604

 2003–2004 33.5 (27.4 – 40.9) 2.26 (1.63 – 2.71) 33.8 (27.9 – 46.2) 299 (245 – 425) 554

 2005–2006 33.3 (27.5 – 40.3) 2.39 (.618 – 4.04) 36.2 (30.4 – 47.2) 318 (207 – 523) 583

40–59 years

 1999–2000 26.4 (21.9 – 31.9) <LOD 31.8 (27.4 – 38.7) 293 (217 – 358) 414

 2001–2002 37.1 (30.0 – 45.7) <LOD 44.2 (37.7 – 51.2) 246 (180 – 305) 531

 2003–2004 33.8 (27.6 – 41.5) 1.16 (<LOD – 2.44) 40.8 (33.6 – 47.8) 369 (241 – 719) 452

 2005–2006 41.6 (31.7 – 54.5) 2.95 (<LOD – 5.29) 46.6 (34.2 – 61.6) 375 (276 – 802) 449

60 years and older

 1999–2000 28.6 (23.0 – 35.6) <LOD 33.5 (29.2 – 43.9) 258 (186 – 430) 507

 2001–2002 41.9 (35.8 – 49.2) 3.67 (2.14 – 6.71) 46.3 (41.8 – 50.8) 238 (220 – 360) 519

 2003–2004 49.4 (42.8 – 57.0) 5.75 (1.73 – 6.45) 57.1 (51.9 – 63.1) 309 (230 – 697) 518

 2005–2006 41.3 (33.4 – 51.1) 2.15 (<LOD – 5.47) 45.4 (38.7 – 52.1) 418 (290 – 798) 452

Gender

Males

 1999–2000 19.8 (15.4 – 25.4) <LOD 25.3 (20.6 – 31.1) 198 (153 – 287) 1,206

 2001–2002 28.7 (26.0 – 31.7) <LOD 31.4 (27.0 – 36.7) 212 (184 – 259) 1,375

 2003–2004 31.1 (27.5 – 35.0) 2.03 (1.17 – 3.66) 34.8 (32.2 – 38.4) 249 (195 – 368) 1,244

 2005–2006 32.5 (26.7 – 39.5) 2.46 (.565 – 4.41) 34.2 (29.5 – 41.0) 310 (229 – 493) 1,252

Females

 1999–2000 29.3 (25.0 – 34.4) <LOD 35.3 (29.6 – 41.6) 320 (233 – 370) 1,321

 2001–2002 38.9 (34.9 – 43.3) 3.35 (<LOD – 4.62) 43.8 (39.3 – 48.7) 234 (185 – 305) 1,419

 2003–2004 43.6 (38.3 – 49.7) 2.76 (2.24 – 4.15) 49.0 (43.4 – 57.7) 375 (280 – 464) 1,350

 2005–2006 41.4 (36.1 – 47.4) 3.10 (.952 – 5.10) 48.2 (41.8 – 55.7) 372 (277 – 473) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 19.6 (17.3 – 22.2) <LOD 23.2 (19.8 – 28.6) 193 (164 – 233) 791

 2001–2002 28.7 (24.5 – 33.7) 2.60 (<LOD – 3.88) 31.0 (27.0 – 36.9) 220 (157 – 338) 679

 2003–2004 29.9 (23.8 – 37.4) 1.88 (<LOD – 2.68) 33.8 (26.7 – 42.4) 240 (211 – 401) 653

 2005–2006 34.4 (28.3 – 41.8) 3.45 (2.15 – 3.97) 35.3 (30.9 – 39.6) 314 (245 – 578) 634

Non-Hispanic Blacks

 1999–2000 16.5 (13.9 – 19.5) <LOD 18.4 (14.4 – 22.8) 173 (136 – 311) 597

 2001–2002 24.5 (19.4 – 30.8) 1.76 (<LOD – 3.48) 27.0 (22.6 – 33.4) 157 (127 – 387) 692

 2003–2004 28.4 (24.2 – 33.3) 3.18 (2.04 – 3.81) 30.1 (26.1 – 36.0) 202 (158 – 230) 681

 2005–2006 24.3 (20.5 – 28.9) 1.66 (.980 – 2.91) 25.3 (22.1 – 30.3) 186 (147 – 251) 662

Non-Hispanic Whites

 1999–2000 28.7 (24.5 – 33.6) <LOD 34.4 (28.9 – 39.3) 252 (210 – 366) 899

 2001–2002 35.2 (31.5 – 39.4) 2.50 (<LOD – 2.90) 40.8 (34.4 – 46.8) 225 (198 – 276) 1,211

 2003–2004 39.5 (34.5 – 45.3) 2.71 (2.21 – 3.73) 45.5 (38.4 – 53.4) 299 (249 – 402) 1,069

 2005–2006 39.2 (33.3 – 46.1) 2.99 (.537 – 5.09) 45.0 (39.4 – 50.2) 330 (284 – 441) 1,039

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
H 

H 

H H 

0 

20 

40 

60 

50th Percentile

H 

H 

H 

H 

H 

H 

H 

H H 

H 

H H 

H 

H 

H H H 

H 

H H 

H 

H

H H 

H 

H 

H 

H 

H 

H 

H H 

H H 

H 

H 

0 

200 

400 

600 

95th Percentile

H 

H 

H H 

H H 

H 

H 

H H 

H 

H 

H H 

H 

H H 

H 

H H 

H 

H H 

H 

H H 

H H 

H 

H 

H 

H 

Figure 4.10.b. Urinary enterodiol (creatinine corrected): 

Concentrations by survey cycle 

Selected percentiles in μg/g creatinine (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006 

5th Percentile 

10 

8 

6 

4 

2 

0 

H 

H 

H 

H 

H 

H 

H 

H 

H 

H 

H 

H H H H H 

H 

H H 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

4. Isoflavones and Lignans 425
426

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population Table 4.11.a.1. Urinary enterolactone: Concentrations Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. Geometric mean (95% conf. interval) Selected percentiles (95% conf. interval) Sample size 2.5th 5th 50th 95th 97.5th Total, 6 years and older 290 (266 – 317) 5.51 (3.93 – 6.69) 10.9 (9.27 – 14.5) 390 (350 – 435) 2,740 (2,560 – 2,980) 3,800 (3,390 – 4,340) 5,122 Age group 6–11 years 340 (287 – 403) 11.4 (3.72 – 23.1) 25.6 (13.5 – 35.2) 413 (334 – 503) 2,150 (1,770 – 2,590) 2,670 (2,250 – 4,230) 692 12–19 years 303 (270 – 339) 5.99 (4.82 – 9.04) 14.0 (8.09 – 18.1) 394 (363 – 445) 2,560 (2,020 – 2,900) 3,290 (2,860 – 4,900) 1,422 20–39 years 272 (236 – 314) 6.15 (2.81 – 9.09) 10.8 (7.26 – 17.6) 349 (307 – 413) 2,810 (2,460 – 3,380) 3,930 (3,330 – 6,420) 1,137 40–59 years 271 (231 – 317) 3.90 (2.39 – 5.55) 7.59 (4.89 – 12.1) 389 (310 – 461) 3,050 (2,470 – 3,640) 4,130 (3,220 – 5,180) 901 60 years and older 327 (288 – 371) 5.82 (1.91 – 9.57) 14.1 (8.96 – 17.7) 476 (396 – 559) 2,690 (2,360 – 3,330) 3,460 (2,960 – 5,610) 970 Gender Males 307 (275 – 343) 5.60 (3.53 – 8.21) 12.5 (9.00 – 15.7) 424 (378 – 468) 2,850 (2,600 – 3,150) 3,790 (3,210 – 4,530) 2,496 Females 275 (242 – 313) 5.15 (3.46 – 6.73) 10.3 (8.69 – 14.3) 364 (321 – 422) 2,630 (2,360 – 3,070) 3,780 (3,190 – 5,400) 2,626 Race/ethnicity Mexican Americans 315 (282 – 352) 6.62 (5.35 – 9.21) 16.7 (8.05 – 25.3) 402 (364 – 435) 2,410 (2,040 – 2,940) 3,300 (2,670 – 4,760) 1,287 Non-Hispanic Blacks 299 (270 – 331) 5.73 (2.54 – 6.66) 11.0 (6.72 – 15.2) 421 (365 – 469) 2,300 (2,210 – 2,670) 3,140 (2,820 – 3,770) 1,343 Non-Hispanic Whites 287 (256 – 322) 5.56 (3.56 – 7.65) 11.0 (8.84 – 16.5) 387 (336 – 447) 2,740 (2,510 – 3,130) 3,850 (3,350 – 4,520) 2,108
6−11 12−19 20−39 40−59 60+ 

0 200 400 600 800 

Urinary enterolactone (μg/L) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

800 

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 4.11.a. Urinary enterolactone: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary enterolactone Urinary enterolactone (μg/L) (μg/L) 0 200 400 600 800 0 200 400 600 

6−11 12−19 20−39 40−59 60+ 6−11 12−19 20−39 40−59 60+ 

Females Males 

6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

6−11 12−19 20−39 40−59 60+ 

4. Isoflavones and Lignans 427
428 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.11.a.2. Urinary enterolactone: Total population

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the total U.S. population aged 6 

years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 290 (266 – 317) 26.5 (23.0 – 30.9) 390 (350 – 435) 1,810 (1,700 – 1,970) 5,122

6–11 years 340 (287 – 403) 56.2 (32.4 – 76.6) 413 (334 – 503) 1,490 (1,200 – 1,880) 692

12–19 years 303 (270 – 339) 27.3 (19.2 – 44.1) 394 (363 – 445) 1,680 (1,490 – 1,910) 1,422

20–39 years 272 (236 – 314) 26.5 (20.2 – 35.4) 349 (307 – 413) 1,780 (1,540 – 2,060) 1,137

40–59 years 271 (231 – 317) 19.8 (14.2 – 26.7) 389 (310 – 461) 1,950 (1,560 – 2,430) 901

60 years and older 327 (288 – 371) 30.1 (18.9 – 42.3) 476 (396 – 559) 2,020 (1,790 – 2,300) 970

Males

Total, 6 years and older 307 (275 – 343) 28.8 (23.3 – 36.5) 424 (378 – 468) 1,910 (1,730 – 2,060) 2,496

6–11 years 408 (324 – 514) 79.9 (45.3 – 126) 481 (381 – 582) 1,520 (1,140 – 2,130) 340

12–19 years 318 (272 – 371) 28.6 (20.1 – 51.1) 418 (369 – 495) 1,800 (1,530 – 2,240) 728

20–39 years 259 (211 – 318) 26.2 (16.7 – 37.4) 334 (244 – 427) 1,790 (1,530 – 2,320) 499

40–59 years 297 (241 – 365) 21.7 (12.8 – 32.5) 427 (309 – 537) 2,050 (1,530 – 2,950) 451

60 years and older 373 (318 – 438) 38.9 (20.7 – 59.7) 551 (441 – 651) 2,040 (1,690 – 2,720) 478

Females

Total, 6 years and older 275 (242 – 313) 24.6 (19.9 – 28.9) 364 (321 – 422) 1,770 (1,540 – 2,000) 2,626

6–11 years 280 (233 – 336) 32.3 (24.1 – 57.3) 346 (260 – 445) 1,420 (1,080 – 2,230) 352

12–19 years 288 (250 – 331) 23.3 (16.5 – 47.6) 372 (320 – 421) 1,520 (1,370 – 1,730) 694

20–39 years 286 (242 – 337) 27.3 (20.2 – 38.7) 354 (311 – 443) 1,760 (1,360 – 2,500) 638

40–59 years 248 (197 – 313) 19.3 (10.8 – 26.6) 349 (271 – 421) 1,840 (1,450 – 2,330) 450

60 years and older 294 (239 – 362) 26.8 (16.3 – 41.8) 424 (323 – 541) 2,010 (1,700 – 2,280) 492

Table 4.11.a.3. Urinary enterolactone: Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/L) for Mexican Americans in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 315 (282 – 352) 39.4 (28.0 – 48.8) 402 (364 – 435) 1,630 (1,460 – 1,930) 1,287

6–11 years 278 (238 – 325) 53.7 (36.8 – 70.2) 348 (265 – 403) 1,100 (898 – 1,510) 231

12–19 years 344 (288 – 411) 54.9 (36.7 – 77.6) 447 (386 – 526) 1,590 (1,280 – 2,050) 445

20–39 years 329 (276 – 393) 38.9 (21.1 – 56.1) 389 (334 – 471) 1,900 (1,470 – 2,650) 282

40–59 years 295 (220 – 396) 28.5 (12.0 – 43.9) 411 (286 – 578) 1,510 (1,260 – 2,150) 157

60 years and older 305 (192 – 484) 29.7 (6.75 – 60.8) 438 (204 – 673) 1,800 (1,270 – 5,730) 172

Males

Total, 6 years and older 320 (276 – 372) 38.3 (25.0 – 51.0) 423 (362 – 501) 1,700 (1,490 – 2,030) 625

6–11 years 305 (243 – 382) 55.3 (34.8 – 94.5) 367 (243 – 433) 1,210 (862 – 1,960) 112

12–19 years 331 (249 – 440) 46.6 (31.6 – 67.2) 441 (325 – 562) 1,660 (1,180 – 2,480) 228

20–39 years 303 (224 – 411) 25.1 (6.52 – 63.5) 390 (276 – 518) 1,890 (1,350 – 2,780) 117

40–59 years 340 (230 – 504) 28.6† (12.2 – 44.6) 540 (286 – 673) 1,500† (1,250 – 3,450) 85

60 years and older 399 (215 – 739) 38.2† (4.50 – 106) 521 (205 – 1,080) 2,030† (1,350 – 6,680) 83

Females

Total, 6 years and older 309 (268 – 356) 43.0 (21.6 – 57.0) 366 (317 – 436) 1,560 (1,280 – 1,960) 662

6–11 years 252 (201 – 316) 46.3 (32.3 – 56.2) 319 (243 – 407) 1,010 (776 – 1,740) 119

12–19 years 358 (286 – 449) 65.0 (31.6 – 94.3) 446 (356 – 567) 1,460 (1,160 – 2,040) 217

20–39 years 363 (283 – 466) 45.0 (14.8 – 74.7) 383 (310 – 566) 1,900 (1,260 – 3,510) 165

40–59 years 253 (177 – 360) 21.0† (5.66 – 44.2) 317 (192 – 525) 1,440† (920 – 3,070) 72

60 years and older 245 (142 – 423) 18.4† (5.17 – 52.4) 267 (149 – 676) 1,690† (994 – 3,320) 89

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 429

Table 4.11.a.4. Urinary enterolactone: Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic blacks in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 299 (270 – 331) 26.0 (21.3 – 43.2) 421 (365 – 469) 1,580 (1,450 – 1,790) 1,343

6–11 years 429 (362 – 509) 117 (55.9 – 164) 419 (348 – 565) 1,560 (1,350 – 2,070) 207

12–19 years 370 (335 – 408) 46.6 (30.1 – 64.8) 523 (472 – 569) 1,640 (1,460 – 1,970) 496

20–39 years 264 (215 – 326) 23.0 (10.3 – 45.2) 437 (305 – 538) 1,410 (1,210 – 2,230) 249

40–59 years 248 (195 – 316) 19.8 (7.86 – 31.8) 326 (239 – 423) 1,630 (1,390 – 2,210) 231

60 years and older 349 (267 – 455) 39.2 (14.7 – 66.3) 551 (368 – 611) 1,760 (1,270 – 2,330) 160

Males

Total, 6 years and older 320 (272 – 375) 30.8 (17.1 – 56.8) 439 (339 – 549) 1,740 (1,480 – 2,210) 661

6–11 years 425 (348 – 519) 123† (89.3 – 164) 363 (303 – 558) 1,460† (1,320 – 2,160) 99

12–19 years 397 (345 – 457) 58.9 (34.1 – 79.3) 502 (412 – 605) 1,770 (1,420 – 2,810) 258

20–39 years 287 (212 – 389) 24.9 (6.85 – 46.6) 444 (248 – 595) 1,860 (1,430 – 3,290) 116

40–59 years 288 (198 – 419) 16.4 (2.90 – 78.2) 344 (236 – 698) 1,880 (1,380 – 2,860) 114

60 years and older 295 (191 – 456) 17.8† (4.36 – 60.4) 520 (287 – 646) 1,290† (1,080 – 2,200) 74

Females

Total, 6 years and older 282 (253 – 315) 23.9 (18.9 – 43.7) 418 (356 – 464) 1,470 (1,310 – 1,750) 682

6–11 years 434 (324 – 582) 94.1† (22.9 – 174) 531 (364 – 624) 1,590† (1,140 – 2,390) 108

12–19 years 344 (294 – 402) 33.9 (15.3 – 59.8) 530 (439 – 596) 1,590 (1,350 – 1,910) 238

20–39 years 247 (187 – 327) 18.0 (8.47 – 45.5) 421 (246 – 540) 1,180 (934 – 1,760) 133

40–59 years 220 (166 – 291) 21.5 (6.67 – 39.7) 303 (178 – 410) 1,530 (1,140 – 2,250) 117

60 years and older 387 (271 – 553) 44.3† (10.3 – 109) 575 (365 – 666) 1,770† (1,430 – 2,340) 86

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.11.a.5. Urinary enterolactone: Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/L) for non-Hispanic whites in the U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 287 (256 – 322) 26.3 (22.3 – 31.2) 387 (336 – 447) 1,810 (1,650 – 2,010) 2,108

6–11 years 355 (279 – 452) 56.3 (25.8 – 99.3) 456 (279 – 562) 1,480 (1,100 – 2,250) 193

12–19 years 292 (248 – 344) 27.1 (17.2 – 54.8) 369 (325 – 424) 1,660 (1,390 – 1,950) 378

20–39 years 254 (207 – 312) 26.3 (18.2 – 35.4) 313 (235 – 389) 1,640 (1,410 – 2,290) 494

40–59 years 266 (219 – 323) 19.1 (12.2 – 26.9) 393 (300 – 480) 1,850 (1,510 – 2,440) 448

60 years and older 347 (301 – 401) 33.4 (20.6 – 45.2) 495 (427 – 588) 2,060 (1,800 – 2,400) 595

Males

Total, 6 years and older 308 (265 – 358) 29.4 (22.9 – 38.0) 434 (374 – 489) 1,900 (1,660 – 2,160) 1,035

6–11 years 454 (328 – 629) 97.2† (29.3 – 181) 528 (338 – 805) 1,560† (1,070 – 2,670) 99

12–19 years 304 (245 – 379) 27.8 (10.6 – 56.7) 391 (337 – 493) 1,760 (1,360 – 2,340) 191

20–39 years 234 (173 – 316) 25.4 (9.45 – 38.0) 269 (194 – 400) 1,570 (1,300 – 2,460) 217

40–59 years 303 (232 – 397) 22.0 (9.47 – 38.6) 437 (304 – 578) 2,130 (1,580 – 2,880) 229

60 years and older 404 (339 – 482) 40.6 (21.8 – 72.4) 596 (454 – 697) 2,080 (1,700 – 2,780) 299

Females

Total, 6 years and older 268 (227 – 316) 24.6 (19.0 – 29.0) 350 (294 – 415) 1,760 (1,450 – 2,090) 1,073

6–11 years 267 (199 – 358) 26.4† (12.5 – 71.6) 278 (207 – 488) 1,390† (1,040 – 3,010) 94

12–19 years 279 (224 – 347) 21.0 (14.5 – 64.0) 336 (257 – 404) 1,540 (1,020 – 1,990) 187

20–39 years 277 (224 – 342) 26.9 (19.5 – 35.1) 335 (264 – 408) 1,770 (1,230 – 2,790) 277

40–59 years 232 (177 – 305) 17.1 (8.39 – 26.9) 348 (220 – 423) 1,730 (1,250 – 2,200) 219

60 years and older 308 (245 – 388) 29.2 (17.2 – 42.6) 434 (323 – 570) 2,040 (1,690 – 2,360) 296

† Estimate is subject to greater uncertainty due to small cell size. 
430 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.11.b. Urinary enterolactone: Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/L) for the U.S. population, National 

Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 239 (200 – 286) 8.77 (4.68 – 13.0) 315 (246 – 380) 2,800 (2,520 – 3,200) 2,548

 2001–2002 259 (233 – 287) 9.27 (6.84 – 11.8) 350 (314 – 389) 2,720 (1,970 – 3,440) 2,794

 2003–2004 298 (265 – 334) 13.9 (10.0 – 17.9) 395 (332 – 462) 2,620 (2,370 – 2,980) 2,594

 2005–2006 283 (245 – 327) 9.40 (5.54 – 14.3) 384 (339 – 456) 2,880 (2,540 – 3,170) 2,528

Age group

6–11 years

 1999–2000 308 (219 – 432) 34.7 (< LOD – 45.9) 354 (243 – 473) 2,790 (1,850 – 4,390) 331

 2001–2002 288 (245 – 339) 23.4 (12.0 – 41.1) 329 (275 – 405) 2,190 (1,520 – 2,610) 396

 2003–2004 384 (287 – 513) 36.1 (8.67 – 75.5) 414 (303 – 557) 2,300 (1,750 – 3,760) 341

 2005–2006 300 (242 – 373) 19.6 (4.34 – 30.0) 390 (279 – 544) 1,890 (1,420 – 2,630) 351

12–19 years

 1999–2000 250 (191 – 327) 10.0 (3.06 – 16.5) 316 (244 – 408) 2,920 (2,270 – 4,630) 746

 2001–2002 267 (231 – 308) 16.1 (10.1 – 20.0) 318 (256 – 398) 2,170 (1,620 – 3,480) 744

 2003–2004 314 (267 – 369) 18.4 (6.64 – 26.0) 399 (335 – 461) 2,620 (2,120 – 3,080) 729

 2005–2006 292 (245 – 348) 9.91 (5.93 – 14.9) 393 (350 – 490) 2,320 (1,830 – 3,090) 693

20–39 years

 1999–2000 231 (182 – 293) 8.06 (1.33 – 17.0) 303 (228 – 380) 2,660 (2,310 – 4,310) 535

 2001–2002 242 (196 – 301) 8.89 (6.56 – 10.9) 335 (263 – 419) 2,890 (1,870 – 4,740) 604

 2003–2004 279 (224 – 349) 14.1 (6.47 – 23.0) 372 (289 – 474) 2,500 (1,830 – 3,330) 554

 2005–2006 265 (218 – 322) 9.63 (4.72 – 19.0) 337 (276 – 381) 3,130 (2,410 – 7,470) 583

40–59 years

 1999–2000 211 (161 – 278) 2.50 (.690 – 7.44) 297 (229 – 401) 2,970 (2,250 – 5,070) 420

 2001–2002 250 (187 – 333) 7.35 (3.98 – 11.5) 369 (278 – 429) 2,880 (1,870 – 4,820) 531

 2003–2004 271 (231 – 319) 10.2 (7.40 – 12.5) 372 (281 – 429) 2,720 (2,350 – 4,400) 452

 2005–2006 270 (203 – 360) 5.04 (2.73 – 13.3) 397 (299 – 539) 3,060 (2,260 – 4,030) 449

60 years and older

 1999–2000 261 (205 – 331) 10.3 (4.10 – 18.7) 315 (238 – 417) 2,680 (2,240 – 4,580) 516

 2001–2002 288 (247 – 334) 8.74 (3.09 – 17.8) 386 (311 – 451) 2,450 (1,710 – 3,460) 519

 2003–2004 327 (287 – 372) 17.3 (9.92 – 21.1) 457 (367 – 547) 2,690 (2,360 – 3,170) 518

 2005–2006 327 (260 – 410) 11.9 (6.63 – 17.1) 507 (374 – 632) 2,680 (2,070 – 4,400) 452

Gender

Males

 1999–2000 254 (212 – 304) 10.4 (6.45 – 12.8) 351 (266 – 417) 2,720 (2,460 – 3,480) 1,219

 2001–2002 262 (233 – 295) 9.23 (6.76 – 10.9) 339 (314 – 386) 3,040 (2,310 – 4,570) 1,375

 2003–2004 314 (280 – 351) 17.8 (10.7 – 21.9) 424 (375 – 474) 2,610 (2,120 – 3,340) 1,244

 2005–2006 301 (247 – 368) 9.40 (4.26 – 14.9) 421 (347 – 512) 3,110 (2,750 – 3,520) 1,252

Females

 1999–2000 226 (180 – 284) 6.64 (.711 – 16.8) 287 (237 – 340) 2,810 (2,280 – 4,450) 1,329

 2001–2002 255 (226 – 288) 9.25 (5.66 – 13.9) 356 (298 – 397) 2,190 (1,720 – 3,140) 1,419

 2003–2004 283 (233 – 343) 10.5 (9.33 – 15.6) 369 (282 – 464) 2,620 (2,270 – 3,420) 1,350

 2005–2006 267 (220 – 324) 9.18 (6.13 – 15.1) 357 (318 – 444) 2,650 (2,210 – 3,340) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 212 (169 – 265) 6.58 (.710 – 13.4) 281 (232 – 338) 2,690 (2,430 – 3,350) 813

 2001–2002 275 (221 – 342) 12.6 (4.92 – 26.8) 347 (313 – 395) 2,320 (1,650 – 3,490) 679

 2003–2004 275 (239 – 316) 9.35 (6.08 – 15.6) 375 (316 – 434) 2,240 (1,920 – 3,170) 653

 2005–2006 359 (311 – 415) 26.7 (18.2 – 38.6) 418 (363 – 514) 2,640 (2,010 – 3,390) 634

Non-Hispanic Blacks

 1999–2000 262 (194 – 352) 8.91 (.671 – 17.0) 360 (293 – 449) 2,480 (1,990 – 4,170) 594

 2001–2002 279 (224 – 347) 7.85 (3.49 – 15.7) 420 (339 – 488) 1,980 (1,690 – 2,530) 692

 2003–2004 324 (282 – 372) 15.5 (6.01 – 26.1) 425 (358 – 525) 2,230 (1,960 – 2,630) 681

 2005–2006 276 (237 – 322) 7.55 (5.86 – 11.4) 410 (346 – 483) 2,560 (2,210 – 3,030) 662

Non-Hispanic Whites

 1999–2000 247 (196 – 312) 8.26 (2.25 – 15.6) 317 (241 – 401) 2,990 (2,530 – 4,070) 901

 2001–2002 268 (236 – 305) 9.30 (6.94 – 11.8) 356 (308 – 398) 2,780 (1,960 – 3,810) 1,211

 2003–2004 301 (256 – 355) 16.3 (10.1 – 19.8) 397 (307 – 490) 2,650 (2,340 – 3,340) 1,069

 2005–2006 274 (228 – 329) 9.17 (4.29 – 14.8) 372 (318 – 459) 2,900 (2,420 – 3,340) 1,039

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 
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99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

Figure 4.11.b. Urinary enterolactone: Concentrations by survey cycle 

Selected percentiles in μg/L (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006 

4. Isoflavones and Lignans 431
432

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.12.a.1. Urinary enterolactone (creatinine corrected): Concentrations

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 6 years and older 277 (252 – 305) 5.55 (4.13 – 6.95) 11.2 (9.15 – 13.5) 375 (341 – 418) 2,500 (2,250 – 2,890) 3,780 (3,380 – 4,390) 5,122Age group6–11 years 368 (312 – 434) 14.6 (7.65 – 30.5) 33.6 (21.0 – 47.1) 463 (382 – 535) 2,120 (1,770 – 2,530) 2,630 (2,300 – 3,430) 692

12–19 years 225 (203 – 250) 6.79 (4.71 – 8.45) 11.3 (7.51 – 14.7) 290 (271 – 307) 1,470 (1,330 – 1,790) 2,180 (1,580 – 3,540) 1,422

20–39 years 232 (200 – 269) 4.10 (2.40 – 8.49) 9.56 (6.42 – 13.7) 314 (273 – 363) 2,440 (1,860 – 3,750) 3,780 (2,880 – 5,890) 1,137

40–59 years 274 (231 – 326) 4.59 (2.61 – 6.17) 8.62 (5.64 – 13.1) 366 (323 – 468) 2,870 (2,260 – 4,000) 4,880 (3,470 – 6,600) 901

60 years and older 383 (334 – 438) 6.04 (2.51 – 9.36) 13.5 (8.69 – 18.9) 582 (502 – 671) 2,780 (2,480 – 3,620) 4,110 (3,400 – 5,060) 970

GenderMales 244 (216 – 275) 4.80 (2.78 – 6.36) 10.7 (6.43 – 13.5) 336 (298 – 371) 2,110 (1,930 – 2,310) 2,930 (2,440 – 3,460) 2,496

Females 313 (275 – 357) 6.82 (4.83 – 8.44) 11.3 (9.39 – 15.4) 418 (360 – 481) 2,890 (2,560 – 3,740) 4,590 (3,880 – 5,900) 2,626

Race/ethnicityMexican Americans 284 (251 – 322) 5.88 (3.39 – 8.31) 14.6 (9.01 – 21.8) 366 (331 – 417) 1,920 (1,670 – 2,260) 2,350 (2,110 – 3,390) 1,287

Non-Hispanic Blacks 210 (189 – 233) 4.37 (2.46 – 5.15) 7.91 (5.58 – 10.8) 294 (274 – 325) 1,480 (1,340 – 1,670) 2,020 (1,690 – 2,300) 1,343

Non-Hispanic Whites 292 (258 – 331) 5.97 (3.88 – 8.66) 12.6 (9.39 – 14.6) 406 (350 – 469) 2,730 (2,330 – 3,370) 4,180 (3,430 – 5,250) 2,108
6−11 12−19 20−39 40−59 60+ 

0 200 400 600 800 

Urinary enterolactone (μg/g creatinine) 

Overall 

6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

Figure 4.12.a. Urinary enterolactone (creatinine corrected): 

Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2006 Urinary enterolactone Urinary enterolactone (μg/g creatinine) (μg/g creatinine) 0 200 400 600 800 0 200 400 600 800 

Non−Hispanic Blacks 

6−11 12−19 20−39 40−59 60+ 

Females 

6−11 12−19 20−39 40−59 60+ 

Age (years) 

Non−Hispanic Whites 

6−11 12−19 20−39 40−59 60+ 

Males 

6−11 12−19 20−39 40−59 60+ 

Age (years) 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

4. Isoflavones and Lignans 433
434 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.12.a.2. Urinary enterolactone (creatinine corrected): Total population

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the total U.S. 

population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 277 (252 – 305) 26.1 (20.3 – 31.3) 375 (341 – 418) 1,620 (1,480 – 1,800) 5,122

6–11 years 368 (312 – 434) 79.9 (44.5 – 104) 463 (382 – 535) 1,480 (1,200 – 1,900) 692

12–19 years 225 (203 – 250) 22.6 (18.0 – 36.1) 290 (271 – 307) 1,140 (996 – 1,220) 1,422

20–39 years 232 (200 – 269) 20.0 (15.1 – 28.5) 314 (273 – 363) 1,460 (1,250 – 1,720) 1,137

40–59 years 274 (231 – 326) 21.1 (15.4 – 28.7) 366 (323 – 468) 1,720 (1,510 – 2,100) 901

60 years and older 383 (334 – 438) 33.8 (22.8 – 46.9) 582 (502 – 671) 2,130 (1,840 – 2,310) 970

Males

Total, 6 years and older 244 (216 – 275) 21.0 (16.3 – 28.5) 336 (298 – 371) 1,400 (1,290 – 1,580) 2,496

6–11 years 409 (329 – 508) 91.0 (45.7 – 127) 471 (395 – 622) 1,380 (1,190 – 2,000) 340

12–19 years 215 (188 – 247) 20.9 (13.6 – 34.9) 292 (258 – 312) 1,150 (924 – 1,390) 728

20–39 years 189 (152 – 234) 16.8 (11.7 – 21.7) 257 (209 – 315) 1,290 (1,050 – 1,610) 499

40–59 years 235 (187 – 296) 18.5 (12.7 – 30.6) 328 (267 – 417) 1,450 (1,230 – 1,930) 451

60 years and older 344 (289 – 409) 35.8 (16.2 – 57.6) 522 (452 – 576) 1,720 (1,490 – 2,210) 478

Females

Total, 6 years and older 313 (275 – 357) 30.0 (22.8 – 35.5) 418 (360 – 481) 1,840 (1,640 – 2,210) 2,626

6–11 years 329 (271 – 399) 56.3 (31.6 – 89.2) 431 (324 – 515) 1,660 (1,080 – 2,310) 352

12–19 years 237 (208 – 270) 25.5 (14.5 – 43.8) 285 (251 – 320) 1,080 (918 – 1,230) 694

20–39 years 284 (237 – 340) 30.8 (15.9 – 42.8) 377 (315 – 431) 1,640 (1,360 – 2,360) 638

40–59 years 316 (253 – 395) 23.7 (15.5 – 32.1) 424 (334 – 585) 2,130 (1,580 – 2,940) 450

60 years and older 417 (336 – 517) 28.3 (19.4 – 53.4) 636 (511 – 784) 2,290 (2,020 – 2,730) 492

 

Table 4.12.a.3. Urinary enterolactone (creatinine corrected): Mexican Americans

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for Mexican Americans in 

the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 284 (251 – 322) 37.6 (27.2 – 48.7) 366 (331 – 417) 1,410 (1,240 – 1,620) 1,287

6–11 years 349 (304 – 400) 79.6 (57.9 – 113) 404 (338 – 472) 1,330 (1,020 – 1,670) 231

12–19 years 266 (225 – 315) 40.1 (26.8 – 56.0) 343 (286 – 397) 1,160 (986 – 1,320) 445

20–39 years 266 (218 – 324) 29.6 (14.6 – 47.7) 328 (257 – 408) 1,480 (1,210 – 1,940) 282

40–59 years 270 (203 – 358) 25.4 (10.6 – 46.6) 400 (291 – 589) 1,190 (898 – 1,770) 157

60 years and older 376 (246 – 576) 29.4 (8.02 – 89.3) 487 (332 – 761) 1,800 (1,550 – 2,210) 172

Males

Total, 6 years and older 253 (219 – 291) 31.0 (22.9 – 44.1) 334 (287 – 401) 1,210 (1,020 – 1,480) 625

6–11 years 365 (292 – 457) 88.4 (58.8 – 127) 403 (290 – 494) 1,390 (956 – 1,970) 112

12–19 years 240 (185 – 312) 31.2 (18.5 – 42.9) 289 (241 – 375) 1,170 (928 – 1,530) 228

20–39 years 220 (167 – 290) 27.2 (3.66 – 48.2) 257 (222 – 396) 1,270 (930 – 1,900) 117

40–59 years 249 (174 – 358) 23.3† (6.34 – 49.2) 399 (235 – 603) 898† (841 – 1,530) 85

60 years and older 355 (200 – 631) 37.2† (3.60 – 128) 503 (322 – 714) 1,540† (1,100 – 6,820) 83

Females

Total, 6 years and older 322 (275 – 378) 40.7 (28.9 – 66.8) 382 (331 – 484) 1,600 (1,330 – 1,870) 662

6–11 years 332 (267 – 413) 64.3 (34.7 – 110) 401 (311 – 538) 1,130 (861 – 1,830) 119

12–19 years 296 (235 – 372) 57.9 (30.5 – 99.0) 378 (316 – 443) 1,100 (860 – 1,350) 217

20–39 years 332 (257 – 430) 39.7 (17.2 – 71.6) 361 (292 – 548) 1,630 (1,300 – 3,210) 165

40–59 years 294 (209 – 414) 28.5† (3.25 – 64.6) 374 (215 – 655) 1,390† (1,090 – 2,590) 72

60 years and older 395 (235 – 663) 25.8† (5.58 – 112) 487 (197 – 1,220) 1,880† (1,590 – 4,100) 89

† Estimate is subject to greater uncertainty due to small cell size. 
4. Isoflavones and Lignans 435

Table 4.12.a.4. Urinary enterolactone (creatinine corrected): Non-Hispanic blacks

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic blacks 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 210 (189 – 233) 20.2 (13.8 – 30.9) 294 (274 – 325) 1,080 (995 – 1,210) 1,343

6–11 years 403 (342 – 476) 126 (82.0 – 147) 469 (378 – 550) 1,300 (1,080 – 1,660) 207

12–19 years 212 (194 – 232) 30.8 (19.9 – 38.3) 282 (251 – 313) 843 (755 – 1,010) 496

20–39 years 164 (133 – 201) 15.8 (10.5 – 22.2) 263 (194 – 306) 914 (741 – 1,040) 249

40–59 years 180 (143 – 228) 11.8 (5.52 – 24.1) 264 (207 – 321) 1,080 (933 – 1,390) 231

60 years and older 311 (242 – 399) 25.1 (12.7 – 61.0) 489 (325 – 693) 1,430 (1,210 – 1,770) 160

Males

Total, 6 years and older 187 (157 – 222) 20.0 (11.2 – 31.3) 267 (223 – 305) 1,050 (940 – 1,200) 661

6–11 years 401 (329 – 489) 122† (69.6 – 153) 417 (332 – 523) 1,220† (1,020 – 1,730) 99

12–19 years 212 (186 – 243) 31.8 (19.4 – 44.2) 264 (222 – 301) 923 (767 – 1,320) 258

20–39 years 138 (103 – 185) 12.2 (2.62 – 27.1) 192 (113 – 291) 969 (657 – 1,180) 116

40–59 years 165 (114 – 238) 10.2 (3.65 – 35.8) 233 (167 – 305) 1,040 (711 – 1,440) 114

60 years and older 217 (142 – 330) 14.8† (3.29 – 51.0) 329 (249 – 440) 1,090† (842 – 3,370) 74

Females

Total, 6 years and older 231 (207 – 259) 20.3 (13.3 – 35.8) 317 (286 – 349) 1,150 (974 – 1,410) 682

6–11 years 405 (308 – 532) 127† (20.6 – 163) 512 (386 – 585) 1,360† (898 – 2,610) 108

12–19 years 212 (180 – 250) 26.0 (11.1 – 39.8) 299 (249 – 360) 814 (727 – 927) 238

20–39 years 188 (144 – 246) 16.1 (7.55 – 32.9) 276 (197 – 347) 820 (619 – 1,360) 133

40–59 years 195 (147 – 258) 11.4 (5.89 – 33.6) 289 (205 – 392) 1,170 (928 – 1,600) 117

60 years and older 391 (275 – 557) 40.6† (9.12 – 96.7) 707 (327 – 822) 1,620† (1,380 – 2,090) 86

† Estimate is subject to greater uncertainty due to small cell size. 

Table 4.12.a.5. Urinary enterolactone (creatinine corrected): Non-Hispanic whites

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for non-Hispanic whites 

in the U.S. population aged 6 years and older, National Health and Nutrition Examination Survey, 2003–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 6 years and older 292 (258 – 331) 26.3 (20.0 – 31.5) 406 (350 – 469) 1,680 (1,510 – 2,020) 2,108

6–11 years 385 (305 – 486) 80.8 (35.3 – 113) 467 (367 – 615) 1,380 (1,170 – 2,000) 193

12–19 years 229 (196 – 267) 22.7 (14.2 – 39.5) 277 (247 – 318) 1,150 (959 – 1,320) 378

20–39 years 234 (188 – 292) 18.7 (12.5 – 29.1) 319 (258 – 417) 1,550 (1,200 – 2,350) 494

40–59 years 286 (232 – 352) 22.5 (14.8 – 30.7) 379 (323 – 500) 1,810 (1,500 – 2,210) 448

60 years and older 415 (358 – 480) 38.5 (23.7 – 57.9) 611 (529 – 717) 2,210 (1,850 – 2,610) 595

Males

Total, 6 years and older 258 (219 – 304) 20.6 (16.0 – 30.1) 360 (309 – 418) 1,490 (1,320 – 1,680) 1,035

6–11 years 440 (322 – 602) 111† (32.6 – 149) 478 (380 – 740) 1,330† (1,150 – 2,850) 99

12–19 years 217 (178 – 265) 20.8 (13.2 – 36.5) 295 (230 – 345) 1,150 (843 – 1,400) 191

20–39 years 185 (134 – 256) 16.1 (5.82 – 20.9) 263 (176 – 362) 1,330 (1,010 – 2,350) 217

40–59 years 254 (190 – 338) 18.8 (12.8 – 34.3) 338 (267 – 497) 1,570 (1,270 – 2,040) 229

60 years and older 377 (313 – 454) 38.1 (18.3 – 61.4) 551 (467 – 666) 1,820 (1,480 – 2,430) 299

Females

Total, 6 years and older 330 (280 – 389) 31.3 (23.1 – 39.4) 447 (375 – 526) 1,990 (1,660 – 2,530) 1,073

6–11 years 330 (250 – 436) 57.0† (24.7 – 98.5) 427 (257 – 554) 1,690† (1,010 – 2,420) 94

12–19 years 242 (198 – 296) 28.8 (12.4 – 75.4) 264 (238 – 320) 1,180 (909 – 1,350) 187

20–39 years 296 (236 – 373) 30.0 (13.3 – 48.8) 417 (312 – 470) 1,690 (1,250 – 3,260) 277

40–59 years 322 (247 – 419) 25.9 (15.8 – 32.6) 445 (323 – 614) 2,130 (1,500 – 3,470) 219

60 years and older 447 (355 – 562) 35.6 (21.3 – 69.1) 662 (529 – 845) 2,400 (2,090 – 3,040) 296

† Estimate is subject to greater uncertainty due to small cell size. 
436 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 4.12.b. Urinary enterolactone (creatinine corrected): 

Concentrations by survey cycle

Geometric mean and selected percentiles of urine concentrations (in μg/g creatinine) for the U.S. population, 

National Health and Nutrition Examination Survey, 1999–2006. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

5th 50th 95th size

Total, 6 years and older

 1999–2000 218 (184 – 260) 7.15 (4.06 – 9.89) 284 (247 – 336) 2,250 (1,890 – 2,930) 2,548

 2001–2002 243 (220 – 268) 7.63 (5.19 – 10.3) 323 (293 – 360) 2,120 (1,790 – 2,460) 2,794

 2003–2004 279 (245 – 317) 12.3 (9.27 – 14.5) 371 (325 – 430) 2,400 (2,030 – 2,890) 2,594

 2005–2006 276 (237 – 321) 9.89 (6.76 – 13.8) 382 (330 – 447) 2,640 (2,260 – 3,380) 2,528

Age group

6–11 years

 1999–2000 315 (238 – 416) 38.6 (<LOD – 66.8) 380 (269 – 431) 2,040 (1,640 – 3,510) 331

 2001–2002 327 (274 – 391) 27.3 (10.5 – 59.2) 349 (264 – 477) 1,980 (1,570 – 3,360) 396

 2003–2004 409 (310 – 540) 41.0 (11.1 – 79.7) 469 (356 – 628) 2,300 (1,750 – 3,390) 341

 2005–2006 331 (268 – 408) 23.4 (8.67 – 46.6) 456 (326 – 526) 1,820 (1,580 – 2,970) 351

12–19 years

 1999–2000 169 (133 – 214) 6.86 (2.00 – 13.6) 209 (172 – 263) 1,820 (1,340 – 2,460) 746

 2001–2002 206 (178 – 239) 12.2 (7.63 – 14.1) 254 (224 – 292) 1,500 (1,240 – 2,730) 744

 2003–2004 235 (202 – 273) 14.7 (6.78 – 20.2) 285 (256 – 307) 1,510 (1,310 – 2,700) 729

 2005–2006 216 (184 – 254) 9.50 (5.93 – 13.1) 296 (254 – 335) 1,410 (1,170 – 1,890) 693

20–39 years

 1999–2000 183 (143 – 235) 5.46 (.836 – 8.94) 248 (199 – 291) 1,900 (1,480 – 3,890) 535

 2001–2002 196 (160 – 240) 4.83 (2.86 – 9.88) 298 (251 – 334) 1,670 (1,430 – 2,450) 604

 2003–2004 235 (186 – 299) 10.0 (4.07 – 14.8) 324 (250 – 422) 2,140 (1,640 – 3,890) 554

 2005–2006 229 (187 – 279) 9.40 (4.07 – 16.0) 299 (256 – 348) 2,630 (1,680 – 6,020) 583

40–59 years

 1999–2000 215 (165 – 279) 4.14 (1.49 – 8.85) 282 (244 – 375) 2,520 (2,030 – 4,780) 420

 2001–2002 248 (191 – 321) 5.90 (3.49 – 10.7) 335 (266 – 435) 2,450 (1,600 – 4,940) 531

 2003–2004 260 (218 – 310) 8.64 (6.33 – 13.5) 354 (300 – 444) 2,450 (2,010 – 4,240) 452

 2005–2006 288 (213 – 389) 8.45 (3.84 – 13.9) 394 (306 – 602) 3,380 (2,280 – 4,890) 449

60 years and older

 1999–2000 313 (227 – 432) 14.0 (3.73 – 20.9) 431 (312 – 611) 2,530 (1,940 – 4,500) 516

 2001–2002 341 (296 – 392) 9.15 (4.22 – 17.6) 432 (383 – 476) 2,550 (2,130 – 3,030) 519

 2003–2004 387 (330 – 453) 18.4 (10.5 – 21.5) 547 (439 – 682) 2,690 (2,340 – 3,340) 518

 2005–2006 379 (300 – 478) 11.9 (6.12 – 17.7) 597 (495 – 730) 3,030 (2,250 – 4,480) 452

Gender

Males

 1999–2000 199 (170 – 234) 7.25 (3.82 – 9.99) 262 (231 – 309) 2,020 (1,810 – 2,480) 1,219

 2001–2002 213 (191 – 238) 6.70 (4.49 – 9.78) 287 (256 – 317) 1,960 (1,620 – 2,660) 1,375

 2003–2004 245 (215 – 280) 12.8 (9.17 – 14.8) 330 (289 – 372) 2,030 (1,770 – 2,390) 1,244

 2005–2006 243 (196 – 300) 8.40 (4.08 – 13.6) 336 (280 – 416) 2,200 (1,930 – 2,640) 1,252

Females

 1999–2000 238 (191 – 297) 7.08 (2.40 – 14.0) 303 (263 – 378) 2,550 (2,010 – 3,520) 1,329

 2001–2002 274 (241 – 312) 9.46 (5.43 – 13.8) 356 (314 – 405) 2,140 (1,970 – 2,430) 1,419

 2003–2004 314 (257 – 385) 11.2 (8.54 – 17.0) 414 (330 – 501) 2,810 (2,290 – 3,940) 1,350

 2005–2006 313 (261 – 375) 12.4 (9.39 – 15.7) 419 (342 – 527) 3,080 (2,520 – 4,780) 1,276

Race/ethnicity

Mexican Americans

 1999–2000 194 (165 – 228) 3.78 (2.01 – 15.3) 253 (224 – 282) 2,020 (1,700 – 2,810) 813

 2001–2002 259 (213 – 314) 13.0 (3.24 – 23.2) 361 (298 – 409) 1,630 (1,320 – 3,010) 679

 2003–2004 248 (217 – 282) 6.88 (4.10 – 14.5) 349 (310 – 397) 1,800 (1,470 – 2,260) 653

 2005–2006 324 (267 – 393) 26.3 (13.0 – 36.2) 378 (321 – 471) 2,030 (1,680 – 2,770) 634

Non-Hispanic Blacks

 1999–2000 168 (124 – 226) 3.12 (.422 – 9.24) 215 (175 – 276) 1,590 (1,220 – 3,280) 594

 2001–2002 195 (153 – 248) 6.71 (4.02 – 9.33) 303 (257 – 334) 1,460 (1,110 – 1,730) 692

 2003–2004 228 (194 – 268) 10.8 (4.54 – 17.1) 300 (274 – 341) 1,460 (1,220 – 2,110) 681

 2005–2006 193 (167 – 223) 6.32 (4.70 – 8.61) 285 (249 – 330) 1,490 (1,290 – 1,660) 662

Non-Hispanic Whites

 1999–2000 243 (194 – 304) 7.71 (3.26 – 11.8) 324 (280 – 389) 2,490 (2,010 – 3,540) 901

 2001–2002 265 (232 – 302) 7.97 (5.19 – 11.8) 340 (299 – 393) 2,400 (1,980 – 2,900) 1,211

 2003–2004 297 (248 – 356) 13.5 (9.57 – 17.5) 409 (331 – 492) 2,590 (2,040 – 3,380) 1,069

 2005–2006 288 (238 – 347) 11.0 (5.96 – 14.9) 403 (329 – 497) 2,910 (2,310 – 4,180) 1,039

< LOD means less than the limit of detection for the uncorrected urine values, which may vary for some compounds by year. See Appendix D for LOD. 
5000 

4000 

H H 

H 

H 

H H 

H 

H H 

H H H 

H H 

H 

H 

H H H 

H 

H 

H 

H 

H 

H 

H 

H 

H 

H H H H 

H H 

H 

H 

5th Percentile 50th Percentile 95th Percentile 3000 

2000 

1000 

800 

600 

400 

200 

0 

80 

60 

40 

20 

0 

H 

H 

H H H

H 

H H 

H 

H 

H H H 

H 

H H 

H H 

H H 

H 

H 

H H 

H 

H H H 

H 

H H H 

H H 

H H 

H H 

H H 

H 

H 

H 

H 

H H 

H 

H H 

H H H H 

H 

H H H H H 

H 

H 

H 

H 

H 

H 

H

H H H 

H H 

99−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−0699−0001−0203−0405−06 

Total 3−5y 6−11y 12−19y 20+y Males Females MA NHB NHW 

(6+y) 

Values in the graph are suppressed if either the point estimate or the lower 95% confidence limit is noted as “< LOD” in the accompanying table. 

Figure 4.12.b. Urinary enterolactone (creatinine corrected): 

Concentrations by survey cycle 

Selected percentiles in μg/g creatinine (95% confidence intervals), National Health and 

Nutrition Examination Survey, 1999–2006

4. Isoflavones and Lignans 437
438 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

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5. Acrylamide Adducts 443

5. Acrylamide Hemoglobin 

Adducts

•	 Acrylamide

•	 Glycidamide

•	 Glycidamide-to-acrylamide ratio
444 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Acrylamide Hemoglobin Adducts

Background Information

Sources. Acrylamide is a chemical naturally found in starchy foods that are cooked at high

temperatures (above 120°C) and low-moisture conditions, such as those used for baking or frying.

There are also several foods in which acrylamide appears to form in high-moisture conditions at

lower temperatures, such as prune juice and canned ripe black olives (Robin 2007). Acrylamide is

formed in food mainly due to a reaction between the amino acid asparagine and reducing sugars,

such as glucose and fructose (Stadler 2002, Mottram 2002). The formation of acrylamide is part

of the Maillard reaction, which leads to browning and flavor changes in cooked foods. Foods that

contain high acrylamide levels include potato chips, crackers, snacks, and coffee (U.S. Food and

Drug Administration 2006, Dybing 2005). Most people consume foods containing acrylamide

on a daily basis. Acrylamide is present in tobacco smoke (Smith 2000), and it is an industrial

chemical used in products for water purification, grouts, packaging, cosmetics, and scientific

research (U.S. Environmental Protection Agency 1994).

Health Effects. High levels of acrylamide can be neurotoxic in both humans and animals and

carcinogenic in animals. Acrylamide has been categorized by the International Agency for

Research on Cancer as a suspected human carcinogen (IARC 1995). In the most recent edition

of the National Toxicology Program Report on Carcinogens, acrylamide has been categorized as

“reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity

from studies in experimental animals” (U.S. National Toxicology Program 2011). The U.S.

Environmental Protection Agency has characterized acrylamide as “likely to be carcinogenic

to humans” (U.S. Environmental Protection Agency 2010). In the body, some acrylamide is

metabolized to glycidamide, an epoxide of acrylamide, through action of cytochrome P450 2E1.

In contrast to acrylamide, glycidamide reacts with DNA in the body and is therefore considered

the genotoxic agent. Acrylamide and glycidamide are cleared through the body mainly by

formation of glutathione adducts and excretion in urine. Neither compound accumulates in the

body.

Intake. The estimated intake of acrylamide from food in the general U.S. population (ages 2 and

older) is on average 0.44 microgram per kilogram bodyweight per day (μg/kg bw/day), with a

90th percentile of 0.95 μg/kg bw/day. Children 2–5 years of age consume about twice the amount

that adults consume (U.S. Food and Drug Administration 2006, Tran 2010). These levels are

about 100 times below those known to cause neurotoxic effects or cancer in animals. The lifelong

exposure of most of the population to acrylamide through food and smoking has, however, raised

concerns about its potential health effects at these low levels of intake. Initial studies using food

intake questionnaires to investigate possible associations between acrylamide intake and various

cancers mostly did not find any associations (Hogervorst 2010). To obtain more information

about the actual acrylamide exposure in the body, further investigations using biomarkers of

acrylamide exposure were recommended.

Biochemical Indicators and Methods. Hemoglobin adducts of acrylamide and glycidamide

reliably reflect the internal dose of acrylamide during the preceding two to four months

(Bergmark 1991, Törnqvist 2002). The measured hemoglobin adduct levels reflect a timeweighted average of exposure over the lifetime of the erythrocyte (Fennell 1992). Hemoglobin

adducts show a high within-person correlation over time, suggesting that a single blood

measurement is a relatively good indicator of long-term acrylamide intake (Wilson 2009).

Hemoglobin adducts, however, are not specific with regard to the source of acrylamide intake or
5. Acrylamide Adducts 445

exposure. Therefore, studies using these biomarkers to investigate acrylamide intake from foods

need to control for exposures from other sources, such as smoking. Persons who smoke tobacco

products have higher acrylamide exposure than those not smoking (Vesper 2007). Exposure to

second hand smoke seems to have a small but significant effect on hemoglobin adduct levels in

non-smokers (Vesper 2010).

Analytical methods measuring hemoglobin adducts of acrylamide determine the adducts

at the N-terminal valine of the hemoglobin protein chains. Initial methods employed gas

chromatography coupled with mass spectrometry; these methods were based on a modified

Edman reaction, which was first described for measuring N-terminal hemoglobin adducts of

ethylene oxide, propylene oxide, and styrene oxide (Mowrer 1986). These initial methods were

further developed and optimized to measure hemoglobin adducts of acrylamide and glycidamide

(Törnqvist 1986, Vesper 2006).

Data in NHANES. No data exist on acrylamide hemoglobin adduct concentrations in NHANES

prior to 2003. This report shows first-time NHANES data for hemoglobin adducts of acrylamide

and glycidamide. Data presented in this report were generated by use of high-performance liquid

chromatography coupled to tandem mass spectrometry (LC-MS/MS); this method uses stable

isotope labeled peptide adducts (same amino acid sequence as hemoglobin) of acrylamide and

glycidamide as internal standards (Vesper 2008).

Highlights

The first-time acrylamide hemoglobin adduct concentrations in the U.S. population showed the

following demographic patterns and characteristics:

•	 Hemoglobin adduct concentrations were detectable in 98% of all blood samples

measured.

•	 We found demographic differences for the glycidamide-to-acrylamide hemoglobin

adduct ratios, but no consistent age, gender, or race/ethnicity patterns for the

hemoglobin adduct concentrations.

New data from NHANES 2003–2004 allow us for the first time to assess the exposure of the

U.S. population to acrylamide. Measurement of hemoglobin adducts provides information both

about acrylamide exposure and metabolism. The glycidamide-to-acrylamide hemoglobin adduct

ratio can be used as an indicator of the extent of acrylamide metabolism and thus as an indicator

of formation of the genotoxic metabolite glycidamide in the body and its detoxification. Children

had higher glycidamide-to-acrylamide hemoglobin adduct ratios compared to adolescents and

adults (Figure H.5.a), suggesting differences in acrylamide metabolism or metabolic rate among

age groups (Vesper 2010). Non-Hispanic blacks (NHB) had lower hemoglobin adduct ratios

compared to non-Hispanic whites (NHW) and Mexican Americans (MA), which may indicate

differences in polymorphisms of the genes involved in phase II detoxification of acrylamide and

glycidamide (Vesper 2010). More research is needed to better understand factors influencing

acrylamide metabolism and the relationship between acrylamide exposure and health risks.
446 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Figure H.5.a. Geometric mean of glycidamide-to-acrylamide hemoglobin adduct ratio in the U.S. population aged 3 years and older, 

National Health and Nutrition Examination Survey, 2003–2004.

Error bars represent 95 percent confidence intervals.

Detailed Observations

The selected observations mentioned below are derived from the tables and figures presented next.

Statements about categorical differences between demographic groups noted below are based on

non-overlapping confidence limits from univariate analysis without adjusting for demographic

variables (e.g., age, sex, race/ethnicity) or other blood concentration determinants (e.g., dietary

intake, supplement usage, smoking, BMI). A multivariate analysis may alter the size and statistical

significance of these categorical differences. Furthermore, additional significant differences of

smaller magnitude may be present despite their lack of mention here (e.g., if confidence limits

slightly overlap or if differences are not statistically significant before covariate adjustment has

occurred). For a selection of citations of descriptive NHANES papers related to these biochemical

indicators of diet and nutrition, see Appendix G.

Geometric mean concentrations (NHANES 2003–2004):

•	 Acrylamide and glycidamide hemoglobin adduct concentrations were comparable across

age groups except for older persons, who had lower concentrations (Tables 5.1.a.1 and

5.2.a.1; Figures 5.1.a and 5.2.a).

•	 Acrylamide (Table 5.1.a.1) and glycidamide hemoglobin adduct concentrations (Table

5.2.a.1) were comparable for males and females.

•	 Acrylamide hemoglobin adduct concentrations were comparable across the three race/

ethnic groups (Table 5.1.a). Non-Hispanic blacks had lower glycidamide hemoglobin

adduct concentrations than both non-Hispanic whites and Mexican Americans (Table

5.2.a.1).

•	 Glycidamide-to-acrylamide hemoglobin adduct ratios were higher in children (3-5 and

6-11 years of age) compared to adolescents and adults, higher in females compared to

males, and lower in non-Hispanic blacks compared to both non-Hispanic whites and

Mexican Americans (Table 5.3.a.1 and Figure 5.3.a).

0.6 

0.8 

1 

1.2 

1.4 

Total 

3-5 

6-11 

12-19 

20-30 40-59 

60 

Males 

Females 

MA 

NHB 

NHW 

Hemoglobin adduct ratio 

Age (years) Gender Race/ethnicity 
5. Acrylamide Adducts 447
448

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 5.1.a.1. Acrylamide hemoglobin adduct: Concentrations

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for the total U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 3 years and older 61.2 (58.1 – 64.4) 25.7 (23.7 – 26.8) 29.2 (27.6 – 30.5) 54.7 (52.8 – 57.6) 192 (170 – 219) 236 (219 – 277) 7,101

Age group3–5 years 59.4 (53.6 – 65.7) 30.9† (28.9 – 34.0) 35.9 (29.7 – 38.0) 58.2 (52.5 – 64.7) 108 (90.3 – 229) 115† (107 – 238) 3506–11 years 58.6 (56.1 – 61.2) 31.5 (27.2 – 35.1) 36.1 (32.2 – 38.7) 57.3 (55.1 – 59.6) 98.7 (91.3 – 103) 106 (101 – 137) 76912–19 years 57.4 (54.4 – 60.5) 28.4 (25.7 – 29.8) 31.4 (30.0 – 32.6) 54.4 (52.1 – 57.3) 132 (118 – 156) 173 (147 – 214) 1,88920–39 years 68.5 (64.1 – 73.3) 26.5 (23.9 – 28.4) 30.3 (28.0 – 31.7) 59.8 (57.0 – 63.9) 225 (200 – 254) 270 (237 – 341) 1,40640–59 years 64.0 (59.9 – 68.4) 24.1 (22.2 – 27.0) 29.1 (26.1 – 31.2) 55.1 (52.1 – 59.1) 219 (189 – 250) 256 (227 – 328) 1,16460 years and older 50.1 (47.9 – 52.3) 21.6 (19.1 – 23.3) 26.0 (23.2 – 27.2) 46.5 (44.1 – 49.1) 140 (126 – 153) 175 (151 – 211) 1,523GenderMales 63.9 (60.2 – 67.9) 26.0 (23.0 – 28.0) 29.0 (27.2 – 31.1) 56.9 (53.6 – 60.0) 219 (195 – 237) 257 (236 – 305) 3,509Females 58.7 (55.9 – 61.5) 25.0 (23.3 – 26.2) 29.4 (27.9 – 30.3) 53.3 (51.8 – 55.8) 164 (149 – 196) 213 (179 – 253) 3,592Race/ethnicityMexican Americans 61.7 (58.7 – 64.9) 33.4 (29.4 – 35.5) 36.5 (34.5 – 38.3) 57.4 (54.4 – 60.3) 149 (127 – 186) 211 (186 – 244) 1,792

Non-Hispanic Blacks 63.8 (57.1 – 71.2) 23.9 (23.1 – 24.7) 27.3 (26.0 – 29.1) 57.0 (51.9 – 64.0) 217 (181 – 285) 285 (233 – 357) 1,818

Non-Hispanic Whites 62.3 (58.9 – 65.9) 26.5 (24.1 – 27.7) 29.6 (28.2 – 31.3) 55.2 (52.9 – 58.5) 196 (175 – 223) 235 (222 – 276) 2,958

† Estimate is subject to greater uncertainty due to small cell size. 
3−5 6−11 12−19 20−39 40−59 60+ 

0 50 100 150

Acrylamide hemoglobin adduct (pmol/g Hb) 

Overall 

3−5 6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

150

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 5.1.a. Acrylamide hemoglobin adduct: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Acrylamide hemoglobin Acrylamide hemoglobin adduct (pmol/g Hb) adduct (pmol/g Hb) 0 50 100 150 0 50 100 

3−5 6−11 12−19 20−39 40−59 60+ 3−5 6−11 12−19 20−39 40−59 60+ 

Females Males 

3−5 6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

3−5 6−11 12−19 20−39 40−59 60+ 

5. Acrylamide Adducts 449
450 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 5.1.a.2. Acrylamide hemoglobin adduct: Total population

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for the total U.S. 

population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 61.2 (58.1 – 64.4) 33.7 (32.4 – 35.1) 54.7 (52.8 – 57.6) 140 (125 – 155) 7,101

3–5 years 59.4 (53.6 – 65.7) 38.5 (33.3 – 42.9) 58.2 (52.5 – 64.7) 90.2 (83.2 – 108) 350

6–11 years 58.6 (56.1 – 61.2) 39.6 (37.9 – 42.7) 57.3 (55.1 – 59.6) 86.7 (81.9 – 93.0) 769

12–19 years 57.4 (54.4 – 60.5) 35.6 (33.8 – 37.1) 54.4 (52.1 – 57.3) 99.9 (91.0 – 115) 1,889

20–39 years 68.5 (64.1 – 73.3) 35.1 (32.5 – 37.7) 59.8 (57.0 – 63.9) 164 (153 – 195) 1,406

40–59 years 64.0 (59.9 – 68.4) 33.5 (31.9 – 35.3) 55.1 (52.1 – 59.1) 160 (142 – 190) 1,164

60 years and older 50.1 (47.9 – 52.3) 29.6 (27.7 – 31.2) 46.5 (44.1 – 49.1) 96.1 (90.2 – 107) 1,523

Males

Total, 3 years and older 63.9 (60.2 – 67.9) 33.6 (31.3 – 35.6) 56.9 (53.6 – 60.0) 152 (140 – 177) 3,509

3–5 years 59.8 (53.2 – 67.2) 38.8 (30.3 – 43.5) 57.8 (49.4 – 65.8) 91.4 (82.7 – 115) 189

6–11 years 58.1 (55.2 – 61.1) 39.6 (35.4 – 41.9) 56.6 (54.7 – 59.3) 86.5 (81.2 – 91.3) 370

12–19 years 57.8 (53.7 – 62.3) 35.0 (32.0 – 37.2) 53.9 (51.1 – 57.7) 107 (94.6 – 127) 976

20–39 years 73.0 (66.9 – 79.7) 35.0 (30.8 – 38.7) 63.8 (59.3 – 68.6) 209 (168 – 228) 655

40–59 years 66.7 (62.2 – 71.6) 33.4 (29.3 – 36.0) 57.3 (51.0 – 64.1) 177 (150 – 205) 572

60 years and older 52.6 (47.8 – 57.9) 29.1 (27.4 – 31.3) 48.0 (42.9 – 52.8) 117 (96.9 – 143) 747

Females

Total, 3 years and older 58.7 (55.9 – 61.5) 33.9 (32.7 – 35.1) 53.3 (51.8 – 55.8) 125 (112 – 143) 3,592

3–5 years 58.9 (52.9 – 65.5) 37.6 (22.3 – 43.7) 59.5 (53.1 – 63.3) 86.1 (79.4 – 134) 161

6–11 years 59.1 (56.5 – 61.8) 40.4 (36.7 – 44.2) 57.4 (55.2 – 60.2) 86.9 (81.0 – 97.5) 399

12–19 years 56.9 (54.5 – 59.5) 36.9 (33.7 – 37.9) 55.3 (53.0 – 57.7) 97.5 (87.4 – 109) 913

20–39 years 64.3 (60.5 – 68.3) 35.2 (33.0 – 37.5) 56.8 (54.4 – 59.5) 152 (131 – 163) 751

40–59 years 61.6 (56.6 – 67.0) 33.4 (32.1 – 35.4) 53.8 (50.2 – 58.9) 151 (125 – 186) 592

60 years and older 48.1 (46.7 – 49.6) 29.8 (27.2 – 31.7) 45.4 (44.3 – 46.9) 84.0 (77.5 – 93.6) 776

Table 5.1.a.3. Acrylamide hemoglobin adduct: Mexican Americans

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for Mexican Americans 

in the U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 61.7 (58.7 – 64.9) 40.0 (38.2 – 42.1) 57.4 (54.4 – 60.3) 101 (95.4 – 115) 1,792

3–5 years 62.0 (57.8 – 66.6) 45.6† (39.5 – 48.1) 59.6 (56.9 – 65.0) 87.4† (78.8 – 104) 90

6–11 years 61.6 (58.2 – 65.3) 44.3 (40.9 – 45.6) 61.4 (55.9 – 67.0) 88.3 (84.0 – 96.4) 250

12–19 years 57.3 (53.8 – 61.0) 38.7 (37.4 – 40.1) 55.2 (51.4 – 59.8) 86.9 (79.6 – 96.5) 590

20–39 years 64.5 (59.9 – 69.5) 40.7 (38.6 – 42.6) 57.5 (54.6 – 60.4) 118 (96.2 – 191) 321

40–59 years 60.9 (55.2 – 67.1) 38.7 (33.8 – 42.2) 56.1 (48.4 – 63.9) 117 (91.6 – 153) 208

60 years and older 57.5 (53.9 – 61.4) 36.5 (31.9 – 38.3) 53.9 (50.0 – 57.9) 108 (91.3 – 120) 333

Males

Total, 3 years and older 65.7 (60.9 – 70.9) 41.4 (38.6 – 43.4) 58.2 (55.0 – 62.6) 122 (103 – 185) 882

3–5 years 63.2 (57.5 – 69.5) 47.3† (40.5 – 48.8) 59.8 (57.1 – 65.5) 88.0† (74.1 – 122) 47

6–11 years 63.5 (59.7 – 67.6) 44.5 (40.8 – 48.3) 62.5 (59.6 – 68.1) 92.0 (84.2 – 102) 117

12–19 years 60.1 (55.8 – 64.8) 39.4 (36.8 – 41.5) 56.8 (53.7 – 61.0) 96.3 (85.5 – 124) 301

20–39 years 70.8 (60.5 – 82.9) 42.1 (37.6 – 44.7) 59.4 (53.2 – 66.6) 176 (111 – 353) 146

40–59 years 63.0 (57.3 – 69.3) 39.2† (25.0 – 44.2) 54.8 (50.1 – 59.7) 124† (92.9 – 193) 109

60 years and older 61.6 (57.0 – 66.5) 36.7 (32.5 – 38.2) 58.0 (51.6 – 64.0) 118 (101 – 151) 162

Females

Total, 3 years and older 57.6 (54.8 – 60.6) 39.0 (36.5 – 40.8) 55.4 (52.0 – 59.4) 89.0 (82.5 – 96.2) 910

3–5 years 60.7 (55.9 – 65.8) 43.4† (36.4 – 48.5) 59.5 (49.3 – 68.0) 82.5† (77.2 – 102) 43

6–11 years 59.5 (55.3 – 64.1) 44.0 (39.6 – 45.0) 58.4 (52.3 – 65.7) 82.2 (79.6 – 96.2) 133

12–19 years 54.5 (50.1 – 59.3) 38.1 (35.0 – 39.7) 53.1 (47.3 – 60.0) 79.4 (72.0 – 93.5) 289

20–39 years 58.2 (54.6 – 62.0) 39.1 (34.9 – 41.9) 55.1 (50.8 – 60.9) 94.5 (81.1 – 108) 175

40–59 years 58.6 (51.4 – 66.7) 38.7† (35.6 – 39.6) 57.8 (45.5 – 66.9) 94.9† (82.2 – 138) 99

60 years and older 54.2 (48.2 – 60.9) 35.7 (19.3 – 40.4) 50.5 (46.3 – 57.3) 85.6 (79.3 – 110) 171

† Estimate is subject to greater uncertainty due to small cell size. 
5. Acrylamide Adducts 451

Table 5.1.a.4. Acrylamide hemoglobin adduct: Non-Hispanic blacks

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for non-Hispanic blacks 

in the U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 63.8 (57.1 – 71.2) 32.3 (30.6 – 33.9) 57.0 (51.9 – 64.0) 156 (123 – 210) 1,818

3–5 years 58.7 (53.4 – 64.5) 39.9 (34.1 – 44.1) 56.0 (53.0 – 62.9) 87.1 (74.3 – 156) 126

6–11 years 57.1 (53.6 – 60.8) 38.6 (33.8 – 41.1) 56.7 (52.3 – 60.4) 85.6 (77.4 – 97.8) 277

12–19 years 58.6 (53.3 – 64.3) 34.4 (31.6 – 36.7) 55.2 (52.3 – 58.9) 110 (97.5 – 138) 667

20–39 years 73.8 (60.9 – 89.4) 33.2 (29.8 – 37.8) 64.4 (53.5 – 80.8) 209 (155 – 293) 290

40–59 years 67.9 (59.3 – 77.8) 32.3 (28.5 – 34.5) 59.4 (49.7 – 69.9) 182 (152 – 250) 259

60 years and older 48.1 (42.3 – 54.6) 24.5 (21.4 – 26.1) 43.1 (39.3 – 50.7) 106 (94.7 – 133) 199

Males

Total, 3 years and older 68.7 (60.8 – 77.6) 32.1 (29.1 – 34.8) 61.7 (55.2 – 68.2) 194 (140 – 241) 918

3–5 years 58.5 (52.4 – 65.4) 37.0† (25.8 – 45.7) 55.7 (52.2 – 65.1) 88.3† (74.7 – 158) 70

6–11 years 54.5 (51.1 – 58.1) 37.7 (31.8 – 40.3) 55.5 (48.5 – 59.4) 75.3 (70.6 – 97.3) 133

12–19 years 60.7 (53.5 – 68.9) 35.2 (30.8 – 37.2) 55.8 (50.8 – 63.8) 121 (102 – 161) 356

20–39 years 89.4 (72.1 – 111) 34.0 (29.9 – 40.4) 86.5 (66.6 – 110) 240 (202 – 361) 142

40–59 years 70.0 (59.3 – 82.6) 29.0 (20.9 – 33.2) 63.9 (51.4 – 72.9) 207 (158 – 290) 123

60 years and older 54.2 (45.8 – 64.2) 25.4† (21.5 – 28.9) 46.2 (40.9 – 61.0) 116† (98.5 – 230) 94

Females

Total, 3 years and older 59.8 (53.4 – 66.8) 32.4 (30.2 – 34.4) 54.5 (48.3 – 60.5) 133 (106 – 171) 900

3–5 years 58.9 (52.3 – 66.3) 43.6† (32.2 – 45.3) 56.2 (48.4 – 67.3) 82.9† (67.1 – 129) 56

6–11 years 60.1 (55.2 – 65.4) 39.4 (35.3 – 43.2) 58.1 (52.1 – 68.0) 95.1 (85.5 – 106) 144

12–19 years 56.5 (52.2 – 61.0) 33.5 (30.4 – 36.7) 53.7 (51.3 – 57.4) 106 (86.0 – 136) 311

20–39 years 63.2 (52.5 – 75.9) 32.8 (27.1 – 37.6) 56.4 (45.3 – 69.7) 153 (106 – 290) 148

40–59 years 66.3 (57.0 – 77.1) 35.1 (24.1 – 39.3) 56.5 (47.1 – 71.0) 173 (147 – 228) 136

60 years and older 44.2 (38.2 – 51.2) 23.7† (19.4 – 26.0) 41.1 (37.8 – 46.9) 92.1† (69.4 – 143) 105

† Estimate is subject to greater uncertainty due to small cell size. 

Table 5.1.a.5. Acrylamide hemoglobin adduct: Non-Hispanic whites

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for non-Hispanic whites 

in the U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 62.3 (58.9 – 65.9) 34.0 (32.5 – 35.7) 55.2 (52.9 – 58.5) 145 (130 – 165) 2,958

3–5 years 61.1 (51.7 – 72.2) 39.0† (20.8 – 44.7) 58.5 (47.7 – 78.2) 98.7† (82.6 – 118) 93

6–11 years 59.0 (56.2 – 62.0) 39.9 (35.1 – 44.6) 58.0 (55.2 – 60.3) 85.9 (80.4 – 91.5) 178

12–19 years 58.6 (55.3 – 62.2) 36.3 (33.3 – 38.5) 54.9 (52.7 – 57.9) 105 (95.0 – 120) 505

20–39 years 72.2 (67.6 – 77.0) 35.7 (31.4 – 39.4) 63.5 (59.2 – 68.5) 174 (157 – 198) 663

40–59 years 65.3 (60.6 – 70.4) 33.7 (32.1 – 36.1) 56.2 (52.1 – 61.1) 167 (143 – 206) 606

60 years and older 50.4 (47.9 – 53.0) 30.6 (28.5 – 31.9) 46.8 (43.9 – 49.7) 92.3 (84.1 – 113) 913

Males

Total, 3 years and older 64.7 (60.6 – 69.0) 33.9 (31.4 – 36.3) 57.4 (53.1 – 60.9) 155 (141 – 187) 1,441

3–5 years 60.9 (49.4 – 75.0) 41.3† (31.0 – 45.6) 57.3 (44.2 – 82.0) 103† (81.4 – 118) 50

6–11 years 58.6 (55.5 – 61.9) 40.0† (30.1 – 46.5) 56.6 (54.7 – 59.1) 85.9† (77.4 – 94.8) 84

12–19 years 57.8 (53.5 – 62.5) 34.4 (31.7 – 37.0) 52.9 (50.2 – 57.0) 109 (94.7 – 134) 257

20–39 years 76.3 (70.4 – 82.8) 36.1 (30.0 – 41.0) 67.0 (60.9 – 73.8) 213 (166 – 228) 293

40–59 years 68.0 (62.5 – 74.0) 34.6 (29.3 – 38.0) 58.2 (50.8 – 66.1) 183 (150 – 213) 302

60 years and older 52.0 (46.7 – 57.8) 29.8 (27.5 – 31.5) 47.8 (42.4 – 52.5) 110 (87.5 – 136) 455

Females

Total, 3 years and older 60.2 (57.0 – 63.5) 34.3 (32.8 – 35.5) 54.0 (52.1 – 57.1) 135 (119 – 154) 1,517

3–5 years 61.4 (51.2 – 73.6) 37.6† (20.8 – 44.2) 62.2 (47.4 – 75.7) 91.2† (79.5 – 238) 43

6–11 years 59.4 (55.7 – 63.4) 39.7† (28.6 – 44.8) 58.5 (55.3 – 61.2) 84.6† (78.2 – 141) 94

12–19 years 59.5 (56.1 – 63.2) 38.1 (34.4 – 40.4) 57.4 (54.1 – 59.9) 100 (92.2 – 117) 248

20–39 years 68.3 (64.0 – 72.9) 35.4 (30.6 – 39.3) 59.6 (54.7 – 65.8) 160 (147 – 182) 370

40–59 years 62.8 (56.9 – 69.2) 33.3 (32.2 – 35.2) 54.5 (50.3 – 60.7) 155 (129 – 217) 304

60 years and older 49.2 (47.8 – 50.6) 31.3 (29.5 – 33.2) 45.7 (45.0 – 47.4) 84.3 (74.6 – 103) 458

† Estimate is subject to greater uncertainty due to small cell size. 
452

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 5.2.a.1. Glycidamide hemoglobin adduct: Concentrations

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for the total U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 3 years and older 59.3 (56.7 – 62.1) 17.5 (< LOD – 20.9) 24.1 (21.4 – 25.8) 59.9 (57.5 – 62.4) 167 (155 – 183) 205 (193 – 235) 7,278

Age group3–5 years 71.6 (66.9 – 76.7) 35.3† (27.7 – 37.8) 38.9 (33.4 – 46.3) 71.1 (67.0 – 79.1) 126 (121 – 136) 135† (128 – 166) 4116–11 years 74.1 (70.3 – 78.2) 36.8 (33.0 – 38.6) 41.2 (36.8 – 44.6) 75.0 (70.9 – 77.9) 140 (128 – 158) 157 (144 – 201) 78412–19 years 55.4 (51.1 – 60.1) < LOD 23.3 (< LOD – 27.0) 59.2 (56.1 – 62.0) 145 (126 – 171) 173 (152 – 230) 1,93120–39 years 65.0 (61.4 – 68.9) 20.6 (< LOD – 23.8) 26.9 (23.8 – 28.9) 64.0 (60.1 – 68.8) 195 (175 – 220) 244 (221 – 282) 1,44640–59 years 60.1 (56.8 – 63.5) 17.8 (< LOD – 22.8) 24.1 (18.8 – 27.2) 58.8 (55.1 – 61.1) 179 (158 – 201) 210 (194 – 265) 1,17760 years and older 45.5 (42.8 – 48.3) < LOD 18.6 (12.1 – 21.1) 46.8 (44.8 – 49.2) 129 (115 – 145) 163 (141 – 199) 1,529GenderMales 59.5 (56.9 – 62.3) 17.8 (11.3 – 20.7) 24.0 (21.5 – 25.7) 59.3 (56.9 – 61.7) 174 (158 – 199) 219 (193 – 292) 3,604Females 59.1 (56.0 – 62.5) 14.3 (< LOD – 21.4) 24.5 (19.2 – 27.3) 60.4 (57.5 – 63.9) 158 (146 – 175) 197 (183 – 212) 3,674Race/ethnicityMexican Americans 64.7 (61.2 – 68.4) 22.5 (< LOD – 30.5) 32.8 (25.7 – 36.1) 65.4 (61.1 – 69.8) 152 (138 – 171) 199 (167 – 246) 1,841

Non-Hispanic Blacks 53.6 (50.6 – 56.7) < LOD 17.4 (9.74 – 20.9) 55.5 (51.9 – 59.2) 159 (134 – 216) 206 (162 – 315) 1,900

Non-Hispanic Whites 61.1 (57.6 – 64.9) 19.6 (8.65 – 23.2) 25.5 (23.3 – 26.9) 60.6 (57.8 – 64.2) 172 (158 – 195) 213 (196 – 249) 3,008

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. † Estimate is subject to greater uncertainty due to small cell size. 
3−5 6−11 12−19 20−39 40−59 60+ 

0 50 100

Glycidamide hemoglobin adduct (pmol/g Hb) 

Overall 

3−5 6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

100

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 5.2.a. Glycidamide hemoglobin adduct: Concentrations by age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Glycidamide hemoglobin Glycidamide hemoglobin adduct (pmol/g Hb) adduct (pmol/g Hb) 0 50 100 0 50 

3−5 6−11 12−19 20−39 

Females 

40−59 60+ 3−5 6−11 12−19 20−39 

Males 

40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

3−5 6−11 

Age (years) 

12−19 20−39 40−59 60+ 3−5 6−11 

Age (years) 

12−19 20−39 40−59 60+ 

5. Acrylamide Adducts 453
454 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 5.2.a.2. Glycidamide hemoglobin adduct: Total population

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for the total U.S. 

population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 59.3 (56.7 – 62.1) 30.6 (28.7 – 32.4) 59.9 (57.5 – 62.4) 130 (120 – 140) 7,278

3–5 years 71.6 (66.9 – 76.7) 47.8 (39.0 – 51.4) 71.1 (67.0 – 79.1) 118 (107 – 126) 411

6–11 years 74.1 (70.3 – 78.2) 47.5 (43.8 – 49.4) 75.0 (70.9 – 77.9) 121 (113 – 135) 784

12–19 years 55.4 (51.1 – 60.1) 31.5 (27.3 – 33.8) 59.2 (56.1 – 62.0) 113 (96.8 – 141) 1,931

20–39 years 65.0 (61.4 – 68.9) 33.0 (29.9 – 35.4) 64.0 (60.1 – 68.8) 149 (136 – 167) 1,446

40–59 years 60.1 (56.8 – 63.5) 30.6 (27.7 – 32.8) 58.8 (55.1 – 61.1) 139 (124 – 158) 1,177

60 years and older 45.5 (42.8 – 48.3) 24.4 (22.6 – 25.6) 46.8 (44.8 – 49.2) 96.2 (90.6 – 103) 1,529

Males

Total, 3 years and older 59.5 (56.9 – 62.3) 29.8 (27.6 – 32.0) 59.3 (56.9 – 61.7) 136 (124 – 148) 3,604

3–5 years 72.4 (67.5 – 77.7) 47.9 (38.4 – 52.2) 70.7 (66.8 – 76.6) 117 (99.9 – 145) 215

6–11 years 75.7 (71.8 – 79.9) 48.2 (45.6 – 50.3) 75.7 (69.9 – 79.6) 118 (112 – 140) 381

12–19 years 52.8 (48.2 – 57.8) 29.3 (24.5 – 32.7) 57.0 (53.2 – 61.0) 111 (97.5 – 134) 1,000

20–39 years 64.6 (60.9 – 68.6) 32.0 (28.6 – 33.8) 60.6 (57.6 – 65.9) 163 (149 – 174) 681

40–59 years 59.9 (56.3 – 63.8) 29.6 (26.1 – 32.8) 58.9 (54.3 – 62.2) 140 (128 – 164) 577

60 years and older 46.3 (42.8 – 50.1) 24.4 (22.2 – 25.7) 45.8 (41.6 – 48.6) 106 (95.4 – 129) 750

Females

Total, 3 years and older 59.1 (56.0 – 62.5) 31.3 (29.1 – 33.4) 60.4 (57.5 – 63.9) 125 (116 – 135) 3,674

3–5 years 70.8 (63.8 – 78.7) 45.8 (34.1 – 53.1) 72.1 (65.7 – 82.0) 118 (104 – 130) 196

6–11 years 72.4 (67.2 – 77.9) 46.3 (43.6 – 48.3) 73.7 (69.6 – 77.9) 122 (106 – 142) 403

12–19 years 58.3 (52.8 – 64.5) 33.7 (28.7 – 35.7) 60.9 (56.5 – 65.8) 114 (95.9 – 160) 931

20–39 years 65.5 (61.4 – 69.8) 35.2 (31.0 – 38.2) 67.7 (61.4 – 73.7) 136 (123 – 160) 765

40–59 years 60.2 (55.3 – 65.6) 30.7 (27.8 – 34.3) 58.6 (53.1 – 64.8) 137 (115 – 160) 600

60 years and older 44.8 (41.8 – 48.1) 24.4 (21.3 – 26.3) 47.7 (45.2 – 50.8) 87.0 (81.1 – 93.8) 779

Table 5.2.a.3. Glycidamide hemoglobin adduct: Mexican Americans

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for Mexican Americans 

in the U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 64.7 (61.2 – 68.4) 39.4 (38.4 – 40.5) 65.4 (61.1 – 69.8) 118 (111 – 130) 1,841

3–5 years 75.5 (67.6 – 84.3) 49.6 (40.2 – 55.0) 74.4 (65.9 – 87.3) 114 (103 – 164) 117

6–11 years 78.5 (72.8 – 84.6) 52.1 (46.5 – 55.3) 78.5 (76.0 – 81.4) 126 (116 – 140) 256

12–19 years 58.7 (53.3 – 64.5) 37.0 (32.2 – 40.3) 62.3 (55.8 – 67.0) 99.7 (93.8 – 115) 601

20–39 years 64.7 (58.2 – 72.0) 39.0 (35.1 – 42.2) 63.9 (59.4 – 70.5) 128 (108 – 168) 324

40–59 years 61.2 (52.8 – 71.0) 38.4 (17.5 – 41.0) 60.5 (52.9 – 73.0) 115 (103 – 144) 212

60 years and older 57.1 (53.8 – 60.5) 33.1 (29.3 – 36.1) 55.8 (50.6 – 61.9) 107 (97.6 – 117) 331

Males

Total, 3 years and older 64.2 (60.0 – 68.7) 38.3 (33.3 – 39.7) 63.6 (59.3 – 68.4) 129 (114 – 160) 909

3–5 years 77.6 (67.7 – 89.1) 52.5† (35.6 – 58.5) 75.7 (68.5 – 87.5) 124† (101 – 187) 58

6–11 years 82.6 (74.3 – 91.7) 55.2 (48.0 – 60.9) 79.7 (77.4 – 88.6) 128 (115 – 161) 125

12–19 years 60.0 (52.4 – 68.6) 36.4 (28.3 – 40.4) 63.4 (56.3 – 68.4) 115 (91.4 – 159) 306

20–39 years 64.4 (55.9 – 74.2) 38.2 (29.2 – 40.6) 60.1 (54.5 – 67.4) 161 (107 – 279) 146

40–59 years 56.0 (47.0 – 66.6) 32.8† (4.98 – 39.7) 56.5 (49.9 – 62.8) 111† (94.7 – 157) 111

60 years and older 55.6 (52.4 – 59.0) 30.3 (17.5 – 35.1) 54.6 (51.7 – 58.5) 110 (97.4 – 141) 163

Females

Total, 3 years and older 65.2 (60.7 – 70.0) 41.9 (39.3 – 44.1) 67.7 (61.8 – 73.7) 111 (106 – 120) 932

3–5 years 73.2 (63.2 – 84.9) 46.6† (42.6 – 49.5) 72.9 (58.1 – 88.9) 108† (91.8 – 155) 59

6–11 years 73.8 (66.6 – 81.8) 47.4 (43.0 – 52.2) 74.0 (66.4 – 81.5) 119 (108 – 144) 131

12–19 years 57.3 (52.7 – 62.4) 37.1 (33.5 – 40.9) 61.2 (54.4 – 67.2) 94.5 (88.0 – 102) 295

20–39 years 65.1 (55.1 – 76.8) 42.4 (28.4 – 46.4) 68.9 (63.2 – 77.5) 114 (104 – 131) 178

40–59 years 67.4 (57.3 – 79.3) 39.8† (34.4 – 43.6) 67.4 (54.8 – 81.6) 118† (105 – 156) 101

60 years and older 58.4 (52.1 – 65.5) 36.0 (27.3 – 39.4) 56.8 (46.6 – 65.2) 104 (87.4 – 124) 168

† Estimate is subject to greater uncertainty due to small cell size. 
5. Acrylamide Adducts 455

Table 5.2.a.4. Glycidamide hemoglobin adduct: Non-Hispanic blacks

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for non-Hispanic blacks 

in the U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 53.6 (50.6 – 56.7) 27.1 (24.4 – 29.8) 55.5 (51.9 – 59.2) 121 (110 – 142) 1,900

3–5 years 66.3 (58.9 – 74.6) 41.3 (26.9 – 48.6) 70.0 (58.0 – 79.8) 101 (96.2 – 112) 141

6–11 years 58.7 (54.5 – 63.2) 35.8 (27.2 – 41.1) 63.0 (57.3 – 69.2) 108 (96.7 – 126) 282

12–19 years 49.7 (47.0 – 52.5) 27.0 (24.8 – 29.3) 52.6 (49.5 – 56.1) 106 (87.7 – 124) 690

20–39 years 63.5 (56.8 – 71.1) 33.4 (26.9 – 35.7) 63.7 (55.8 – 73.8) 144 (120 – 228) 311

40–59 years 50.6 (45.2 – 56.7) 23.5 (17.5 – 29.4) 50.9 (46.2 – 56.4) 133 (95.3 – 186) 265

60 years and older 36.3 (32.9 – 40.1) 15.4 (10.4 – 19.4) 39.7 (36.6 – 42.9) 84.6 (79.9 – 98.7) 211

Males

Total, 3 years and older 54.8 (49.8 – 60.4) 26.5 (23.5 – 28.6) 56.4 (52.2 – 61.8) 134 (114 – 162) 956

3–5 years 65.8 (54.8 – 79.0) 40.1† (< LOD – 49.0) 70.8 (54.1 – 84.2) 100† (95.0 – 130) 77

6–11 years 59.5 (53.9 – 65.7) 35.7 (4.48 – 43.5) 62.9 (54.4 – 68.5) 108 (92.6 – 141) 133

12–19 years 48.5 (44.4 – 53.0) 25.3 (21.2 – 27.8) 51.0 (46.6 – 56.0) 113 (90.4 – 141) 369

20–39 years 71.1 (60.0 – 84.3) 33.3 (27.7 – 36.6) 70.1 (57.1 – 83.5) 152 (121 – 309) 154

40–59 years 46.9 (39.1 – 56.2) 17.5 (4.35 – 20.9) 50.3 (43.7 – 56.6) 156 (101 – 207) 124

60 years and older 38.8 (34.7 – 43.3) 19.9† (9.71 – 22.2) 41.2 (33.6 – 47.1) 81.8† (74.1 – 120) 99

Females

Total, 3 years and older 52.5 (49.6 – 55.5) 28.0 (22.2 – 32.1) 55.0 (50.3 – 60.1) 114 (101 – 132) 944

3–5 years 66.9 (60.4 – 74.1) 40.4† (30.2 – 55.7) 68.3 (58.2 – 79.8) 100† (89.7 – 109) 64

6–11 years 57.9 (49.9 – 67.1) 35.7 (< LOD – 41.3) 63.5 (54.0 – 74.1) 106 (96.3 – 120) 149

12–19 years 50.8 (47.2 – 54.7) 30.7 (24.9 – 33.1) 54.1 (50.7 – 57.8) 98.7 (83.2 – 122) 321

20–39 years 58.0 (51.8 – 64.9) 33.3 (< LOD – 35.7) 60.3 (52.6 – 69.8) 130 (111 – 183) 157

40–59 years 53.9 (49.1 – 59.1) 29.8 (22.5 – 33.3) 50.9 (46.1 – 57.8) 115 (90.7 – 169) 141

60 years and older 34.7 (29.2 – 41.2) 14.1 (< LOD – 19.4) 38.7 (34.4 – 42.9) 87.3 (74.8 – 103) 112

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 

Table 5.2.a.5. Glycidamide hemoglobin adduct: Non-Hispanic whites

Geometric mean and selected percentiles of whole blood concentrations (in pmol/g Hb) for non-Hispanic whites 

in the U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 61.1 (57.6 – 64.9) 31.1 (28.9 – 32.8) 60.6 (57.8 – 64.2) 135 (124 – 149) 3,008

3–5 years 75.5 (67.8 – 84.1) 50.7† (37.9 – 53.7) 72.3 (65.8 – 88.4) 121† (114 – 133) 110

6–11 years 78.5 (73.8 – 83.6) 51.3 (43.2 – 55.7) 76.0 (74.1 – 79.5) 123 (109 – 150) 183

12–19 years 57.9 (52.8 – 63.5) 33.4 (27.6 – 34.9) 60.4 (57.1 – 62.9) 115 (97.9 – 148) 512

20–39 years 68.5 (63.9 – 73.5) 32.9 (29.7 – 37.3) 67.5 (61.1 – 72.9) 160 (142 – 176) 682

40–59 years 62.8 (58.4 – 67.5) 31.9 (29.1 – 34.2) 60.4 (56.8 – 64.4) 143 (129 – 164) 610

60 years and older 46.6 (43.1 – 50.5) 25.0 (23.3 – 26.6) 47.7 (45.1 – 50.9) 96.7 (89.9 – 106) 911

Males

Total, 3 years and older 61.0 (57.6 – 64.6) 30.2 (28.2 – 32.5) 60.1 (57.3 – 62.8) 140 (125 – 155) 1,473

3–5 years 74.2 (66.5 – 82.7) 48.0† (37.9 – 55.0) 68.7 (60.3 – 88.3) 118† (98.8 – 195) 58

6–11 years 79.8 (74.8 – 85.1) 55.5† (47.5 – 57.9) 75.8 (70.9 – 84.9) 116† (108 – 156) 87

12–19 years 54.4 (48.8 – 60.7) 30.4 (24.0 – 34.3) 57.3 (53.2 – 60.5) 102 (93.6 – 143) 264

20–39 years 66.7 (62.4 – 71.3) 31.9 (28.5 – 35.3) 62.9 (58.3 – 67.8) 170 (154 – 182) 308

40–59 years 63.7 (58.1 – 69.8) 32.3 (26.5 – 35.6) 60.6 (56.6 – 64.6) 141 (129 – 168) 303

60 years and older 46.9 (42.4 – 51.7) 24.5 (21.1 – 26.4) 45.9 (41.5 – 49.1) 106 (95.5 – 128) 453

Females

Total, 3 years and older 61.2 (57.1 – 65.7) 31.7 (29.1 – 34.3) 61.1 (57.9 – 65.8) 132 (120 – 147) 1,535

3–5 years 77.1 (66.0 – 90.1) 51.9† (< LOD – 60.9) 78.6 (62.4 – 100) 124† (101 – 135) 52

6–11 years 77.2 (70.7 – 84.2) 48.7† (39.3 – 53.1) 76.6 (71.9 – 80.3) 125† (99.1 – 197) 96

12–19 years 62.0 (54.9 – 70.0) 34.4 (27.2 – 41.5) 63.0 (57.9 – 69.5) 119 (99.0 – 168) 248

20–39 years 70.5 (64.4 – 77.1) 36.5 (28.0 – 42.6) 71.2 (63.9 – 78.3) 142 (130 – 191) 374

40–59 years 61.9 (55.7 – 68.9) 30.9 (27.7 – 35.5) 60.0 (54.1 – 68.0) 144 (116 – 182) 307

60 years and older 46.5 (42.7 – 50.6) 25.7 (23.9 – 26.9) 49.3 (46.3 – 51.5) 87.1 (80.4 – 97.9) 458

< LOD means less than the limit of detection, which may vary for some compounds by year. See Appendix D for LOD. 

† Estimate is subject to greater uncertainty due to small cell size. 
456

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 5.3.a.1. Glycidamide-to-acrylamide hemoglobin adduct ratio

Geometric mean and selected percentiles of ratio (no units) of whole blood concentrations (in pmol/g Hb) for the total U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004. 

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

size 2.5th 5th 50th 95th 97.5th

Total, 3 years and older .958 (.923 – .995) .406 (< LOD – .477) .529 (.489 – .562) 1.01 (.984 – 1.03) 1.65 (1.57 – 1.81) 1.88 (1.75 – 2.21) 6,844

Age group3–5 years 1.25 (1.18 – 1.32) .715† (.097 – .835) .836 (.435 – .881) 1.28 (1.23 – 1.38) 1.77 (1.64 – 2.02) 2.00† (1.73 – 2.30) 3366–11 years 1.25 (1.20 – 1.30) .691 (.555 – .772) .807 (.700 – .852) 1.28 (1.23 – 1.33) 2.02 (1.88 – 2.47) 2.51 (2.02 – 4.24) 74212–19 years .952 (.889 – 1.02) < LOD .560 (< LOD – .625) 1.01 (.987 – 1.04) 1.72 (1.52 – 2.47) 2.14 (1.72 – 3.88) 1,81720–39 years .939 (.896 – .985) .419 (< LOD – .492) .537 (.474 – .585) .988 (.939 – 1.03) 1.62 (1.53 – 1.77) 1.84 (1.66 – 2.19) 1,36440–59 years .926 (.883 – .970) .400 (< LOD – .469) .507 (.466 – .540) .974 (.9 35 – 1.01) 1.58 (1.49 – 1.76) 1.75 (1.63 – 2.42) 1,12460 years and older .900 (.855 – .948) < LOD .475 (.359 – .528) .961 (.928 – .984) 1.57 (1.48 – 1.73) 1.78 (1.63 – 2.34) 1,461GenderMales .918 (.886 – .951) .410 (.313 – .470) .514 (.487 – .537) .955 (.926 – .990) 1.58 (1.52 – 1.69) 1.79 (1.66 – 2.09) 3,389Females .999 (.956 – 1.04) .402 (< LOD – .493) .566 (.464 – .622) 1.06 (1.02 – 1.09) 1.72 (1.62 – 1.93) 1.97 (1.79 – 2.59) 3,455Race/ethnicityMexican Americans 1.05 (.987 – 1.11) .513 (< LOD – .603) .616 (.554 – .684) 1.09 (1.03 – 1.16) 1.73 (1.60 – 2.17) 1.99 (1.77 – 2.57) 1,739

Non-Hispanic Blacks .830 (.762 – .904) .098 (.042 – .343) .397 (.141 – .447) .893 (.845 – .949) 1.62 (1.46 – 1.96) 1.82 (1.64 – 2.94) 1,736

Non-Hispanic Whites .967 (.932 – 1.00) < LOD .548 (.507 – .591) 1.01 (.984 – 1.03) 1.63 (1.54 – 1.80) 1.85 (1.71 – 2.18) 2,859

< LOD means less than the limit of detection for either the whole blood acrylamide adduct or the glycidamide adduct, which may vary for some compounds by year. See Appendix D for LOD.† Estimate is subject to greater uncertainty due to small cell size. 
3−5 6−11 12−19 20−39 40−59 60+ 

Glycidamide−to−acrylamide

0.0 0.5 1.0 1.5 2.0

hemoglobin adduct ratio 

Overall 

3−5 6−11 12−19 20−39 40−59 60+ 

Mexican Americans 

Females 

Males 

2.0

Non−Hispanic Blacks Non−Hispanic Whites 

Figure 5.3.a. Glycidamide−to−acrylamide hemoglobin adduct ratio: By age group 

Geometric mean (95% confidence interval), National Health and Nutrition Examination Survey, 2003–2004 Glycidamide−to−acrylamide Glycidamide−to−acrylamide hemoglobin adduct ratio hemoglobin adduct ratio 0.0 0.5 1.0 1.5 2.0 0.0 0.5 1.0 1.5 

3−5 6−11 12−19 20−39 40−59 60+ 3−5 6−11 12−19 20−39 40−59 60+ 

Females Males 

3−5 6−11 12−19 20−39 40−59 60+ 

Mexican

 Americans 

Non−Hispanic

 Blacks 

Non−Hispanic

 Whites 

Age (years) Age (years) 

3−5 6−11 12−19 20−39 40−59 60+ 

5. Acrylamide Adducts 457
458 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 5.3.a.2. Glycidamide-to-acrylamide hemoglobin adduct ratio: Total population

Geometric mean and selected percentiles of ratio (no units) of whole blood concentrations (in pmol/g Hb) for 

the total U.S. population aged 3 years and older, National Health and Nutrition Examination Survey, 2003–2004.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older .958 (.923 – .995) .642 (.620 – .661) 1.01 (.984 – 1.03) 1.48 (1.42 – 1.54) 6,844

3–5 years 1.25 (1.18 – 1.32) .944 (.647 – 1.05) 1.28 (1.23 – 1.38) 1.61 (1.57 – 1.78) 336

6–11 years 1.25 (1.20 – 1.30) .899 (.853 – .923) 1.28 (1.23 – 1.33) 1.72 (1.61 – 1.96) 742

12–19 years .952 (.889 – 1.02) .670 (.609 – .719) 1.01 (.987 – 1.04) 1.45 (1.37 – 1.62) 1,817

20–39 years .939 (.896 – .985) .643 (.606 – .668) .988 (.939 – 1.03) 1.43 (1.38 – 1.51) 1,364

40–59 years .926 (.883 – .970) .618 (.561 – .643) .974 (.935 – 1.01) 1.41 (1.36 – 1.51) 1,124

60 years and older .900 (.855 – .948) .607 (.550 – .649) .961 (.928 – .984) 1.39 (1.32 – 1.49) 1,461

Males

Total, 3 years and older .918 (.886 – .951) .610 (.585 – .632) .955 (.926 – .990) 1.41 (1.35 – 1.49) 3,389

3–5 years 1.25 (1.16 – 1.35) .863 (.621 – 1.06) 1.26 (1.22 – 1.38) 1.60 (1.54 – 1.86) 181

6–11 years 1.28 (1.22 – 1.35) .899 (.846 – .983) 1.31 (1.22 – 1.39) 1.72 (1.66 – 1.97) 359

12–19 years .908 (.842 – .980) .651 (.599 – .677) .984 (.952 – 1.01) 1.38 (1.34 – 1.47) 944

20–39 years .874 (.832 – .918) .607 (.562 – .641) .895 (.862 – .939) 1.25 (1.20 – 1.34) 638

40–59 years .883 (.848 – .920) .573 (.537 – .618) .933 (.895 – .979) 1.34 (1.23 – 1.49) 549

60 years and older .865 (.823 – .908) .558 (.508 – .629) .905 (.860 – .943) 1.35 (1.26 – 1.47) 718

Females

Total, 3 years and older .999 (.956 – 1.04) .679 (.641 – .711) 1.06 (1.02 – 1.09) 1.52 (1.47 – 1.61) 3,455

3–5 years 1.25 (1.17 – 1.34) .971 (.811 – 1.04) 1.29 (1.22 – 1.45) 1.64 (1.51 – 2.07) 155

6–11 years 1.22 (1.15 – 1.29) .898 (.833 – .923) 1.27 (1.20 – 1.29) 1.71 (1.58 – 2.00) 383

12–19 years 1.00 (.928 – 1.08) .730 (.635 – .776) 1.04 (1.00 – 1.10) 1.57 (1.41 – 1.84) 873

20–39 years 1.01 (.958 – 1.07) .690 (.651 – .701) 1.08 (1.02 – 1.13) 1.55 (1.47 – 1.70) 726

40–59 years .967 (.904 – 1.03) .639 (.563 – .706) 1.01 (.957 – 1.07) 1.47 (1.39 – 1.59) 575

60 years and older .929 (.865 – .998) .647 (.534 – .710) .998 (.969 – 1.04) 1.41 (1.35 – 1.52) 743

Table 5.3.a.3. Glycidamide-to-acrylamide hemoglobin adduct ratio: Mexican 

Americans

Geometric mean and selected percentiles of ratio (no units) of whole blood concentrations (in pmol/g Hb) for 

Mexican Americans in the U.S. population aged 3 years and older, National Health and Nutrition Examination 

Survey, 2003–2004.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older 1.05 (.987 – 1.11) .748 (.697 – .780) 1.09 (1.03 – 1.16) 1.57 (1.46 – 1.75) 1,739

3–5 years 1.32 (1.26 – 1.40) 1.06† (.957 – 1.11) 1.33 (1.25 – 1.41) 1.59† (1.54 – 1.88) 89

6–11 years 1.27 (1.17 – 1.37) .953 (.923 – .989) 1.25 (1.19 – 1.34) 1.76 (1.57 – 2.53) 244

12–19 years 1.03 (.965 – 1.09) .767 (.717 – .822) 1.05 (.999 – 1.12) 1.50 (1.42 – 1.73) 568

20–39 years .997 (.904 – 1.10) .689 (.608 – .755) 1.06 (.972 – 1.14) 1.56 (1.42 – 1.77) 312

40–59 years .999 (.918 – 1.09) .718 (.616 – .772) 1.04 (.988 – 1.12) 1.51 (1.36 – 2.60) 202

60 years and older .989 (.908 – 1.08) .716 (.561 – .774) .996 (.936 – 1.05) 1.38 (1.28 – 1.62) 324

Males

Total, 3 years and older .977 (.916 – 1.04) .689 (.616 – .722) 1.01 (.949 – 1.07) 1.52 (1.41 – 1.60) 858

3–5 years 1.35 (1.25 – 1.46) 1.09† (1.02 – 1.15) 1.33 (1.14 – 1.54) 1.60† (1.55 – 1.95) 46

6–11 years 1.29 (1.16 – 1.44) .984 (.102 – 1.06) 1.26 (1.19 – 1.38) 1.85 (1.57 – 4.24) 117

12–19 years .996 (.880 – 1.13) .750 (.602 – .813) 1.03 (.948 – 1.12) 1.49 (1.42 – 1.67) 290

20–39 years .907 (.823 – 1.00) .660 (.532 – .708) .930 (.877 – 1.02) 1.39 (1.19 – 1.64) 141

40–59 years .886 (.775 – 1.01) .611† (.197 – .722) .946 (.872 – 1.01) 1.34† (1.24 – 1.60) 106

60 years and older .906 (.820 – 1.00) .642 (.087 – .750) .937 (.877 – 1.00) 1.28 (1.23 – 1.36) 158

Females

Total, 3 years and older 1.12 (1.06 – 1.19) .847 (.801 – .890) 1.17 (1.10 – 1.25) 1.62 (1.49 – 1.96) 881

3–5 years 1.30 (1.22 – 1.38) .993† (.905 – 1.11) 1.32 (1.25 – 1.40) 1.58† (1.45 – 1.76) 43

6–11 years 1.23 (1.10 – 1.38) .926 (.860 – .977) 1.25 (1.16 – 1.33) 1.68 (1.57 – 1.95) 127

12–19 years 1.06 (1.01 – 1.11) .820 (.716 – .870) 1.08 (1.02 – 1.16) 1.54 (1.39 – 2.11) 278

20–39 years 1.10 (.980 – 1.24) .871 (.658 – .936) 1.17 (1.10 – 1.27) 1.70 (1.50 – 2.10) 171

40–59 years 1.14 (1.04 – 1.25) .823† (.754 – .889) 1.16 (1.04 – 1.36) 1.54† (1.43 – 2.60) 96

60 years and older 1.07 (.919 – 1.24) .777 (.486 – .881) 1.05 (.881 – 1.28) 1.48 (1.32 – 3.87) 166

† Estimate is subject to greater uncertainty due to small cell size. 
5. Acrylamide Adducts 459

Table 5.3.a.4. Glycidamide-to-acrylamide hemoglobin adduct ratio: 

Non-Hispanic blacks

Geometric mean and selected percentiles of ratio (no units) of whole blood concentrations (in pmol/g Hb) for 

non-Hispanic blacks in the U.S. population aged 3 years and older, National Health and Nutrition Examination 

Survey, 2003–2004.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older .830 (.762 – .904) .526 (.440 – .588) .893 (.845 – .949) 1.39 (1.27 – 1.60) 1,736

3–5 years 1.15 (1.08 – 1.23) .865 (.697 – .961) 1.15 (1.07 – 1.24) 1.53 (1.37 – 1.83) 122

6–11 years 1.02 (.927 – 1.13) .708 (.563 – .793) 1.10 (1.00 – 1.20) 1.74 (1.58 – 1.92) 265

12–19 years .834 (.752 – .925) .582 (.484 – .635) .893 (.858 – .931) 1.38 (1.26 – 1.66) 637

20–39 years .865 (.768 – .975) .547 (.424 – .604) .900 (.827 – .974) 1.39 (1.24 – 1.64) 277

40–59 years .720 (.642 – .807) .427 (.340 – .509) .805 (.746 – .874) 1.19 (1.11 – 1.35) 248

60 years and older .752 (.652 – .868) .458 (.184 – .542) .822 (.743 – .915) 1.24 (1.15 – 1.62) 187

Males

Total, 3 years and older .782 (.721 – .847) .512 (.429 – .546) .830 (.784 – .878) 1.31 (1.20 – 1.53) 875

3–5 years 1.17 (1.10 – 1.24) .940† (< LOD – .985) 1.14 (1.08 – 1.24) 1.57† (1.39 – 1.82) 68

6–11 years 1.10 (.985 – 1.23) .711 (.560 – .831) 1.12 (1.02 – 1.20) 1.78 (1.66 – 2.11) 126

12–19 years .770 (.666 – .890) .554 (.420 – .613) .833 (.808 – .859) 1.30 (1.12 – 1.64) 341

20–39 years .797 (.739 – .860) .490 (.431 – .537) .808 (.741 – .880) 1.18 (1.06 – 1.77) 136

40–59 years .628 (.532 – .741) .413 (.073 – .483) .727 (.643 – .809) 1.11 (1.02 – 1.24) 115

60 years and older .717 (.592 – .869) .457† (.046 – .565) .766 (.691 – .853) 1.15† (1.02 – 2.25) 89

Females

Total, 3 years and older .875 (.788 – .972) .581 (.412 – .643) .951 (.885 – 1.00) 1.42 (1.31 – 1.62) 861

3–5 years 1.14 (1.02 – 1.27) .792† (.716 – .967) 1.16 (1.03 – 1.26) 1.48† (1.32 – 2.00) 54

6–11 years .947 (.807 – 1.11) .690 (< LOD – .784) 1.08 (.955 – 1.21) 1.55 (1.32 – 2.11) 139

12–19 years .905 (.815 – 1.00) .603 (.447 – .701) .983 (.921 – 1.05) 1.44 (1.31 – 1.82) 296

20–39 years .924 (.778 – 1.10) .602 (< LOD – .726) .974 (.885 – 1.12) 1.52 (1.36 – 1.89) 141

40–59 years .802 (.728 – .885) .463 (.380 – .602) .870 (.805 – .926) 1.24 (1.15 – 1.48) 133

60 years and older .778 (.643 – .941) .425† (< LOD – .574) .831 (.766 – 1.00) 1.32† (1.15 – 3.57) 98

< LOD means less than the limit of detection for either the whole blood acrylamide adduct or the glycidamide adduct, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.
460 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Table 5.3.a.5. Glycidamide-to-acrylamide hemoglobin adduct ratio: 

Non-Hispanic whites

Geometric mean and selected percentiles of ratio (no units) of whole blood concentrations (in pmol/g Hb) for 

non-Hispanic whites in the U.S. population aged 3 years and older, National Health and Nutrition Examination 

Survey, 2003–2004.

Geometric mean 

(95% conf. interval)

Selected percentiles (95% conf. interval) Sample 

10th 50th 90th size

Males and Females

Total, 3 years and older .967 (.932 – 1.00) .651 (.629 – .675) 1.01 (.984 – 1.03) 1.47 (1.41 – 1.53) 2,859

3–5 years 1.28 (1.15 – 1.43) .863† (.097 – 1.18) 1.32 (1.23 – 1.47) 1.61† (1.56 – 2.05) 89

6–11 years 1.31 (1.23 – 1.38) .939 (.852 – .989) 1.32 (1.27 – 1.38) 1.72 (1.55 – 2.41) 172

12–19 years .979 (.901 – 1.06) .699 (.642 – .748) 1.02 (.981 – 1.07) 1.42 (1.36 – 1.61) 490

20–39 years .939 (.896 – .984) .645 (.610 – .678) .984 (.924 – 1.02) 1.42 (1.37 – 1.51) 648

40–59 years .948 (.910 – .988) .629 (.591 – .658) .986 (.954 – 1.02) 1.41 (1.34 – 1.50) 586

60 years and older .914 (.859 – .972) .631 (.553 – .669) .966 (.935 – .989) 1.40 (1.33 – 1.55) 874

Males

Total, 3 years and older .927 (.898 – .958) .627 (.605 – .649) .955 (.922 – .993) 1.39 (1.33 – 1.48) 1,400

3–5 years 1.24 (1.07 – 1.43) .842† (.621 – 1.10) 1.27 (1.10 – 1.46) 1.57† (1.48 – 2.06) 48

6–11 years 1.32 (1.24 – 1.41) .944† (.748 – 1.03) 1.33 (1.27 – 1.42) 1.70† (1.57 – 2.25) 82

12–19 years .947 (.862 – 1.04) .669 (.609 – .722) 1.01 (.940 – 1.04) 1.37 (1.32 – 1.41) 254

20–39 years .862 (.820 – .905) .609 (.549 – .644) .886 (.852 – .930) 1.24 (1.20 – 1.30) 289

40–59 years .922 (.891 – .954) .619 (.557 – .649) .945 (.910 – .987) 1.33 (1.23 – 1.44) 291

60 years and older .880 (.835 – .929) .570 (.512 – .636) .922 (.862 – .953) 1.38 (1.27 – 1.49) 436

Females

Total, 3 years and older 1.01 (.961 – 1.05) .681 (.648 – .706) 1.06 (1.02 – 1.09) 1.52 (1.45 – 1.62) 1,459

3–5 years 1.33 (1.17 – 1.51) 1.01† (< LOD – 1.19) 1.46 (1.26 – 1.48) 1.72† (1.51 – 2.09) 41

6–11 years 1.29 (1.19 – 1.40) .923† (.777 – .995) 1.28 (1.20 – 1.39) 1.79† (1.54 – 2.97) 90

12–19 years 1.02 (.929 – 1.11) .743 (.636 – .786) 1.05 (.996 – 1.13) 1.57 (1.37 – 1.87) 236

20–39 years 1.02 (.954 – 1.10) .691 (.654 – .700) 1.06 (1.00 – 1.14) 1.55 (1.46 – 1.77) 359

40–59 years .975 (.899 – 1.06) .639 (.513 – .736) 1.02 (.969 – 1.08) 1.43 (1.38 – 1.63) 295

60 years and older .942 (.866 – 1.02) .658 (.528 – .724) 1.00 (.968 – 1.05) 1.43 (1.35 – 1.56) 438

< LOD means less than the limit of detection for either the whole blood acrylamide adduct or the glycidamide adduct, which may vary for some compounds by year. See Appendix D for LOD.

† Estimate is subject to greater uncertainty due to small cell size.
5. Acrylamide Adducts 461

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Törnqvist M, Mowrer J, Jensen S, Ehrenberg L. Monitoring environmental cancer initiators through hemoglobin adducts

by a modified Edman degradation method. Anal. Biochem. 1986;154:255–266.

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chemfact/s_acryla.txt.

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toxreviews/0286tr.pdf.

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462 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population


Appendices 465

Appendices

Appendix A NHANES Reports Related to Nutritional 

Status

Appendix B Information Presented in the Report

Appendix C Cutoff Points used to Generate Prevalence 

Estimates

Appendix D References for Analytical Methods for 

Biochemical Indicators

Appendix E Confidence Interval Estimation for Percentiles

Appendix F Limit of Detection Table

Appendix G Selected References of Descriptive NHANES 

Papers on Diet-and-Nutrition Biochemical 

Indicators
466 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Appendix A

NHANES Reports Related to Nutritional Status

National Center for Health Statistics (NCHS) Data Briefs

http://www.cdc.gov/nchs/products/databriefs.htm

Looker AC, Johnson CL, Lacher DA, Pfeiffer CM, Schleicher RL, Sempos CT. Vitamin D status: 

United States, 2001–2006. NCHS Data Brief, No 59. Hyattsville, MD: National Center for 

Health Statistics. 2011.

McDowell MA, Lacher DA, Pfeiffer CM, Mulinare J, Picciano MF, Rader JI, et al. Blood Folate 

Levels: The Latest NHANES Results. NCHS Data Brief, No 6. Hyattsville, MD: National 

Center for Health Statistics. 2008.

National Center for Health Statistics (NCHS) Advance Data Reports

http://www.cdc.gov/nchs/products/ad.htm

Advance Data No. 349. Prevalence of leading types of dietary supplements used in the Third 

National Health and Nutrition Examination Survey, 1988–94. 8 pp. (PHS) 2005–1250.

Advance Data No. 348. Dietary intake of fats and fatty acids for the United States population: 

1999-2000. 7 pp. (PHS) 2005–1250.

Advance Data No. 341. Dietary intake of selected minerals for the United States population: 

1999–2000. 6 pp. (PHS) 2004–1250.

Advance Data No. 339. Dietary intake of selected vitamins for the United States population: 

1999–2000. 5 pp. (PHS) 2004–1250.

Advance Data No. 334. Dietary intake of ten key nutrients for public health, United States: 

1999–2000. 4 pp. (PHS) 2003–1250.

National Center for Health Statistics (NCHS) Series 11 Reports

http://www.cdc.gov/nchs/products/series/series11.htm

Hollowell JG, van Assendelft OW, Gunter EW, Lewis BG, Najjar M, Pfeiffer C. Hematological 

and iron-related analytes—Reference data for persons aged 1 year and over: United States, 1988–

1994. National Center for Health Statistics. Vital Health Stat Series No. 11(247), 2005.

Bialostosky K, Wright JD, Kennedy-Stephenson J, McDowell M, Johnson CL. Dietary intake 

of macronutrients, micronutrients, and other dietary constituents: United States 1988–1994. 

National Center for Health Statistics. Vital Health Stat Series No. 11(245), 2002.

Ervin RB, Wright JD, Kennedy-Stephenson J. Use of dietary supplements in the United States, 

1988-1994. National Center for Health Statistics. Vital Health Stat Series No. 11(244), 1999.

Wright JD, Bialostosky K, Gunter EW, Carroll MD, Najjar MF, Bowman BA, Johnson CL. Blood 

folate and vitamin B12: United States, 1988–1994. National Center for Health Statistics. Vital 

Health Stat Series No. 11(243), 1998.
Appendices 467

Fulwood R, Johnson CL, Bryner JD, Gunter EW, McGrath CR. Hematological and nutritional 

biochemistry reference data for persons 6 months–74 years of age: United States, 1976–1980. 

National Center for Health Statistics. Vital Health Stat Series No. 11(232), 1982.

National Center for Health Statistics (NCHS) Series 2 Reports

http://www.cdc.gov/nchs/products/series/series02.htm

Looker AC, Gunter EW, Cook JD, Green R, Harris JW. Comparing serum ferritin values from 

different population surveys. National Center for Health Statistics. Vital Health Stat Series No. 

2(111), 1991.

Life Sciences Research Office (LSRO) Reports

Pilch SM. Assessment of the vitamin A nutritional status of the U.S. population based on data 

collected in the Health and Nutrition Examination Surveys. Bethesda (MD): Federation of 

American Societies for Experimental Biology; 1985.

Senti FR, Pilch SM. Analysis of the folate nutritional status of the U.S. population based on 

data collected in the Second National Health and Nutrition Examination Survey, 1976–1980. 

Bethesda (MD): Federation of American Societies for Experimental Biology; 1984.

Pilch SM, Senti FR. Assessment of iron nutritional status of the U.S. population based on 

data collected in the Second National Health and Nutrition Examination Survey, 1976–1980. 

Bethesda (MD): Federation of American Societies for Experimental Biology; 1984.

Pilch SM, Senti FR. Assessment of zinc nutritional status of the U.S. population based on 

data collected in the Second National Health and Nutrition Examination Survey, 1976–1980. 

Bethesda (MD): Federation of American Societies for Experimental Biology; 1984.

Life Sciences Research Office. 1989. An update report on nutrition monitoring in the United 

States. Prepared for the U.S. Department of Agriculture and the U.S. Department of Health and 

Human Services. DHHS Publication No. (PHS) 89–1255. Available from U.S. Government 

Printing Office, Washington, D.C.

Life Sciences Research Office. 1994. Assessment of folate methodology used in the Third National 

Health and Nutrition Survey (NHANES 1988-1994). Prepared for the Center for Food Safety 

and Applied Nutrition, Food and Drug Administration, Department of Health and Human 

Services. Washington, D.C.
468

2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Appendix BInformation Presented in the ReportThe table below provides information on the type of data included for each indicator and the years of NHANES covered.

Indicator Table: Concentrations Figure: Concentrations by age group Tables: Concentrations by race/ethnic group Table and Figure: Concentrations by survey cycle Table(s): Prevalence (Deficiency/Excess) Table(s): Prevalence by survey cycle (Deficiency/Excess) Water-Soluble Vitamins 

B Vitamins and Related Biochemical Compounds

Serum folate 2003–2006 2003–2006 2003–2006 1999–2006 not shown*/none not shown*/noneRed blood cell folate 2003–2006 2003–2006 2003–2006 1999–2006 2003–2006/none 1999–2006/noneSerum pyridoxal-5’-phosphate 2005–2006 2005–2006 2005–2006 none 2005–2006/none none/noneSerum 4-pyridoxic acid 2005–2006 2005–2006 2005–2006 none none/none none/noneSerum vitamin B12 2003–2006 2003–2006 2003–2006 1999–2006 2003–2006/none 1999–2006/nonePlasma homocysteine 2003–2006 2003–2006 2003–2006 1999–2006 2003–2006/none 1999–2006/nonePlasma methylmalonic acid 2003–2004 2003–2004 2003–2004 1999–2004 2003–2004/none 1999–2004/none

Serum vitamin C 2003–2006 2003–2006 2003–2006 2003–2006 2003–2006/none 2003–2006/none

Fat-Soluble Vitamins and Nutrients

Vitamins A and E and Carotenoids

Serum vitamin A 2005-2006 2005-2006 2005-2006 1999-2002; 2005-2006 2005-2006/2005-2006 1999-2002; 2005-2006/ 1999-2002; 2005-2006Serum retinyl palmitate 2005-2006 2005-2006 2005-2006 none none/none none/noneSerum retinyl stearate 2005-2006 not shown* 2005-2006 none none/none none/noneSerum vitamin E 2005-2006 2005-2006 2005-2006 1999-2002; 2005-2006 2005-2006/not shown* 1999-2002; 2005-2006/

not shown*

Serum gamma-tocopherol 2005-2006 2005-2006 2005-2006 1999-2002; 2005-2006 none/none none/noneSerum alpha-carotene 2005-2006 2005-2006 2005-2006 2001-2002; 2005-2006 none/none none/none

Serum trans-beta-carotene 2005-2006 2005-2006 2005-2006 2001-2002; 2005-2006 none/none none/noneSerum cis-beta-carotene 2005-2006 not shown* 2005-2006 2001-2002; 2005-2006 none/none none/noneSerum beta-cryptoxanthin 2005-2006 2005-2006 2005-2006 2001-2002; 2005-2006 none/none none/noneSerum lutein and zeaxanthin 2005-2006 2005-2006 2005-2006 2001-2002; 2005-2006 none/none none/noneSerum trans-lycopene 2005-2006 2005-2006 2005-2006 2001-2002; 2005-2006 none/none none/noneSerum total lycopene 2005-2006 2005-2006 2005-2006 none none/none none/none

Serum 25-hydroxyvitamin D 2003-2006 2003-2006 2003-2006 2001-2006 2003-2006/2003-2006 2001-2006/2001-2006Fatty Acids - Saturated

Plasma myristic acid (14:0) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma palmitic acid (16:0) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma stearic acid (18:0) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma arachidic acid (20:0) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma docosanoic acid (22:0) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma lignoceric acid (24:0) 2003-2004 2003-2004 2003-2004 none none/none none/none
Appendices 469

Indicator Table: Concentrations Figure: Concentrations by age group Tables: Concentrations by race/ethnic group Table and Figure: Concentrations by survey cycle Table(s): Prevalence (Deficiency/Excess) Table(s): Prevalence by survey cycle (Deficiency/Excess) 

Fatty Acids - Monounsaturated

Plasma myristoleic acid (14:1n-5) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma palmitoleic acid (16:1n-7) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma cis-vaccenic acid (18:1n-7) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma oleic acid (18:1n-9) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma eicosenoic acid (20:1n-9) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma docosenoic acid (22:1n-9) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma nervonic acid (24:1n-9) 2003-2004 2003-2004 2003-2004 none none/none none/none

Fatty Acids - Polyunsaturated

Plasma linoleic acid (18:2n-6) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma alpha-linolenic acid (18:3n-3) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma gamma-linolenic acid (18:3n-6) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma eicosadienoic acid (20:2n-6) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma homo-gamma-linolenic acid (20:3n-6) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma arachidonic acid (20:4n-6) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma eicosapentaenoic acid (20:5n-3) 2003-2004 2003-2004 2003-2004 none none/none none/none

Plasma docosatetraenoic acid (22:4n-6) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma docosapentaenoic acid (22:5n-3) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma docosapentaenoic acid (22:5n-6) 2003-2004 2003-2004 2003-2004 none none/none none/nonePlasma docosahexaenoic acid (22:6n-3) 2003-2004 2003-2004 2003-2004 none none/none none/none

Trace Elements

Iron-Status Indicators 

Serum ferritin 2003-2006 2003-2006 2003-2006 1999-2006 2003-2006/ 2003-2006 1999-2006/1999-2006

Serum soluble transferrin receptor 2003-2006 2003-2006 2003-2006 2003-2006 2003-2006/none 2003-2006/noneBody iron 2003-2006 2003-2006 2003-2006 2003-2006 2003-2006/none 2003-2006/none

Urinary iodine 2003-2006 2003-2006 2003-2006 2001-2006 none/none none/none

Isoflavones & Lignans

Urinary genistein 2003-2006 2003-2006 2003-2006 1999-2006 none/none none/noneUrinary daidzein 2003-2006 2003-2006 2003-2006 1999-2006 none/none none/noneUrinary equol 2003-2006 2003-2006 2003-2006 1999-2006 none/none none/noneUrinary O-desmethylangolensin 2003-2006 2003-2006 2003-2006 1999-2006 none/none none/noneUrinary enterodiol 2003-2006 2003-2006 2003-2006 1999-2006 none/none none/noneUrinary enterolactone 2003-2006 2003-2006 2003-2006 1999-2006 none/none none/none

Acrylamide Hemoglobin Adducts

Acrylamide hemoglobin adduct 2003-2004 2003-2004 2003-2004 none none/none none/noneGlycidamide hemoglobin adduct 2003-2004 2003-2004 2003-2004 none none/none none/noneGlycidamide-to-acrylamide hemoglobin adduct ratio 2003-2004 2003-2004 2003-2004 none none/none none/none

* Prevalence table is not shown if most or all estimates have been suppressed because of the RSE being ≥ 40%.
470 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Appendix C

Cutoff Points used to Generate Prevalence Estimates

The table below presents the cutoff values used to calculate prevalence estimates of low or high 

concentrations of biochemical indicators for various population groups and the years for which 

NHANES data were available. The clinical interpretation of the cutoff values is described in the 

text that accompanies each chapter.

Indicator Units Cutoff value Population described NHANES years available

Water-Soluble Vitamins

Serum folate ng/mL < 2 ≥ 3 years 1999–2002

≥ 1 years 2003–2006

Red blood cell folate ng/mL < 95 ≥ 3 years 1999–2002

≥ 1 years 2003–2006

Serum pyridoxal-5’-phosphate nmol/L < 20 ≥ 1 years 2005–2006

Serum vitamin B12 pg/mL < 200 ≥ 3 years 1999–2002

≥ 1 years 2003–2006

Plasma homocysteine μmol/L > 13 ≥ 3 years 1999–2004

≥ 20 years 2005–2006

Plasma methylmalonic acid nmol/L > 271 ≥ 3 years 1999–2004

Serum vitamin C μmol/L < 11.4 ≥ 6 years 2003–2006

Fat-Soluble Vitamins

Serum vitamin A μg/dL < 20 ≥ 6 years 1999–2002; 2005–2006 

μg/dL > 100 ≥ 6 years 1999–2002; 2005–2006

Serum vitamin E μg/dL < 500 ≥ 6 years 1999–2002; 2005–2006

μg/dL > 20,000 ≥ 6 years 1999–2002; 2005–2006

Serum 25-hydroxyvitamin D nmol/L < 30 ≥ 6 years or ≥ 1 year* 2001–2006

nmol/L 30–< 50 ≥ 6 years or ≥ 1 year* 2001–2006

nmol/L < 40 ≥ 6 years or ≥ 1 year* 2001–2006

nmol/L > 125 ≥ 6 years or ≥ 1 year* 2001–2006

Iron-Status Indicators

Serum ferritin ng/mL < 12 1-5 years 1999–2006

ng/mL < 15 Females 12-49 years 1999–2006

ng/mL < 15 Males ≥ 6 years 1999–2002

ng/mL > 150 Females 12-49 years 1999–2006

ng/mL > 200 Males ≥ 12 years 1999–2002

Serum soluble transferrin receptor mg/L > 4.4 Females 12-49 years 2003–2006

Body iron mg/kg < 0 1-5 years 2003–2006

mg/kg < 0 Females 12-49 years 2003–2006

*2001–2002: ≥ 6 years; 2003–2006: ≥ 1 year
Appendices 471

Appendix D

References for Analytical Methods for Biochemical 

Indicators

Detailed Laboratory Procedure Manuals for Each Analytical Method:

•	 NHANES 2003–2004: http://www.cdc.gov/nchs/nhanes/nhanes2003-2004/lab_

methods_03_04.htm.

•	 NHANES 2005–2006: http://www.cdc.gov/nchs/nhanes/nhanes2005-2006/lab_

methods_05_06.htm.

Additional Useful Analytical Method References:

Water-Soluble Vitamins

Gunter EW, Bowman BA, Caudill SP, Twite DB, Adams MJ, Sampson EJ. Results of an international round robin 

for serum folate and whole-blood folate. Clin Chem. 1996;42:1689–1694.

Life Sciences Research Office. Assessment of folate methodology used in the Third National Health and Nutrition 

Survey (NHANES 1988-1994). Washington, D.C.: Center for Food Safety and Applied Nutrition, Food and Drug 

Administration, Department of Health and Human Services; 1994.

McCoy LF, Bowen MB, Xu M, Chen H, Schleicher RL. Improved HPLC assay for measuring serum vitamin C 

with 1-methyluric acid used as an electrochemically active internal standard. Clin Chem. 2005;51:1062–1064.

Pfeiffer CM, Twite D, Shih J, Holets-McCormack SR, Gunter EW. Method comparison for total plasma 

homocysteine between the Abbott IMx analyzer and an HPLC assay with internal standardization. Clin Chem. 

1999;45(1):152–153.

Pfeiffer CM, Huff DL, Smith SJ, Miller DT, Gunter EW. Comparison of plasma total homocysteine measurements 

in 14 laboratories: an international study. Clin Chem. 1999;45(8):1261–1268.

Pfeiffer CM, Smith SJ, Miller DT, Gunter EW. Comparison of serum and plasma methylmalonic acid 

measurements in 13 laboratories: an international study. Clin Chem. 1999;45:2236–2242.

Pfeiffer CM, Caudill SP, Gunter EW, Bowman BA, Jacques PF, Selhub J, et al. Discussion of critical issues related 

to the comparison of homocysteine values between the Third National Health and Nutrition Examination Survey 

(NHANES) and NHANES 1999+. J Nutr. 2000;130:2850–2854.

Rybak ME, Pfeiffer CM. Clinical analysis of vitamin B6: Determination of pyridoxal 5’-phosphate and 4-pyridoxic 

acid in human serum by reversed-phase high-performance liquid chromatography with chlorite postcolumn 

derivatization. Anal Biochem. 2004;333:336–344.

Rybak ME, Jain RB, Pfeiffer CM. Clinical vitamin B6

 analysis: an inter-laboratory comparison of pyridoxal 

5’-phosphate measurements in serum. Clin Chem. 2005;51:1223–1231.

Rybak ME, Pfeiffer CM. A simplified protein precipitation and filtration procedure for determining serum vitamin 

B6 by high-performance liquid chromatography. Anal Biochem. 2009;388:175–177.

Fat-Soluble Vitamins and Nutrients

Sowell AL, Huff DL, Yeager PR, Caudill SP, Gunter EW. Retinol, alpha-tocopherol, lutein/zeaxanthin, betacryptoxanthin, lycopene, alpha-carotene, trans-beta-carotene, and four retinyl esters in serum determined 

simultaneously by reversed-phase HPLC with multi-wavelength detection. Clin Chem. 1994;40:411–416.
472 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Trace Elements

Looker AC, Gunter EW, Johnson CL. Methods to assess iron status in various NHANES surveys. Nutr Rev. 

1995;53:246–254.

Pfeiffer CM, Cook JD, Mei Z, Cogswell ME, Looker AC, Lacher DA. Evaluation of an automated soluble 

transferrin receptor (sTfR) assay on the Roche Hitachi analyzer and its comparison to two ELISA assays. Clin 

Chim Acta 2007;382:112–116.

Caldwell KL, Maxwell CB, Makhmudov A, Pino S, Braverman LE, Jones RL, et al. Use of inductively coupled 

plasma mass spectrometry to measure urinary iodine in NHANES 2000: comparison with previous method. Clin 

Chem. 2003;49:1019–1021.

Isoflavones and Lignans 

Valentin-Blasini L, Blount BC, Rogers HS, Needham LL. HPLC-MS/MS method for the measurement of seven 

phytoestrogens in human serum and urine. J Expo Anal Environ Epidemiol. 2000;10:799–807.

Kuklenyik Z, Ye X, Reich JA, Needham LL, Calafat AM. Automated on-line and off-line solid phase extraction 

methods for measuring isoflavones and lignans in urine. J Chromatogr Sci. 2004;42:495–500.

Rybak ME, Parker DL, Pfeiffer CM. Determination of urinary phytoestrogens by HPLC-MS/MS: a comparison 

of atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI). J Chromatogr B. 

2008;861:145–150.

Parker DL, Rybak ME, Pfeiffer CM. Phytoestrogen biomonitoring: an extractionless LC-MS/MS method for 

measuring urinary isoflavones and lignans using atmospheric pressure photoionization (APPI). Anal Bioanal Chem. 

2012;402:1123-1136.

Acrylamide Hemoglobin Adducts

Vesper HW, Ospina M, Meyers T, Ingham L, Smith A, Gray JG, Myers GL. Automated method for measuring 

globin adducts of acrylamide and glycidamide at optimized Edman reaction conditions. Rapid Commun Mass 

Spectrom. 2006;20:959–964.
Appendices 473

Appendix E

Confidence Interval Estimation for Percentiles

A large body of literature describes various methods to estimate percentiles and to derive the 

variance and confidence intervals for complex survey data. Highlighted in the literature are the 

following methods: Woodruff method (Woodruff 1952), “test inversion” method (Francisco and 

Fuller 1991), the Normal transformation method (Korn and Graubard 1999), and Replication 

methods (Kovar 1988, Rogers 2003).

Confidence intervals for percentiles in this report were calculated with the Woodruff method. 

This method uses the standard error of the empirical distribution function at the selected 

percentile and constructs a 95% confidence interval, followed by back transformation using the 

inverse of the empirical distribution. The previous National Report on Biochemical Indicators 

of Diet and Nutrition in the U.S. Population, 1999–2002 used a variation of the Woodruff 

method by combining it with the method of Clopper and Pearson proposed by Korn and 

Graubard (1999) for complex surveys. This approach was used previously because large-sample 

normal approximations used to calculate confidence intervals for proportions close to zero or 

1 can lead to confidence intervals with poor coverage properties. However, a paper by Sitter 

and Wu (2001) concluded that despite the fact that confidence intervals around the empirical 

distribution function at tail regions perform poorly, the Woodruff confidence intervals obtained 

by inverting these poorly behaved intervals perform very well for percentiles. Therefore, the 

confidence intervals presented in this report are based on the Woodruff approach with no further 

modifications, as described in the steps below.

Background

Define an arbitrary percentile X

p

, such that F(X) = P(X ≤ Xp) = p. This is pictured in Figure 

1, where the y-axis displays the empirical distribution function (cdf) over a set of hypothetical

values. In this example, p = 0.5 and so X0.5 is the median. Both SAS (version 9.2) and SUDAAN 

(version 10.0) find X

p

 through linear interpolation. Let F (x ˆ j) be an estimate of the empirical 

distribution function at x and assume data x1

, x2, ... xn are a rank ordered listing of the sampled 

values, such that x1

 is the minimum value and xn is the maximum value; then the estimated 

percentile by use of linear interpolation is calculated as:

To find the percentiles and confidence intervals in this report, we used results derived from 

SUDAAN’s PROC DESCRIPT (DESIGN=WR) PERCENTILE statement and results from the 

Histogram output group.

 

  xx ˆ p)x(F ˆ ).x(F ˆ )x(F ˆ )x(F

p ˆ )x(F ˆ xX j1j j 1j

1j j

j

jp  



  

 
Figure 1: Definition of a percentile 

P

X

P

Analyte Value

Step 1 

Use SUDAAN (DESIGN=WR) to estimate the percentiles, the empirical distribution, and the 

standard error of the empirical distribution function at each point. SUDAAN uses a HorowitzThompson estimator of the empirical distribution function at each value. The estimated 

empirical distribution function can be outputted into a dataset using the HISTPCT statement in 

conjunction with an OUTPUT statement in PROC DESCRIPT. By default, SUDAAN estimates 

the empirical distribution function by using a maximum of 100 equally spaced percentages to 

divide the population into bins. We used the option /NPCT in the HISTPCT statement to 

change this default to allow a jump in the empirical distribution function at every unique data 

value, up to 2950 unique values. An output file is generated by SUDAAN to contain: the upper 

endpoint of the current bin in the histogram, the cumulative percent less than or equal to the 

upper endpoint of the current bin and the respective estimated standard error of the cumulative 

percent. This file is used to obtain 95% confidence intervals of the empirical distribution function 

at the selected percentile. In some rare cases, using the values of the upper endpoint available in 

this file may differ slightly from a rank order list of the weighted sampled values if there are more 

than 2950 distinct values. This difference may lead to very small differences when comparing the 

confidence limits to other software which uses Woodruff confidence limits based on the weighted 

sample values. Sample SUDAAN code for serum folate (FOL) is as follows: 

474 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population 
Appendices 475

PROC DESCRIPT DATA=NHANES03_06 FILETYPE=SAS DESIGN=WR ;

NEST SDMVSTRA SDMVPSU/MISSUNIT;

WEIGHT WTMEC4YR;

VAR LBXFOL;

PERCENTILES 5 10 90 95 /MEDIAN ;

HISPCT /NPCT=2950;

OUTPUT QTILE /FILENAME=PCTILES 

FILETYPE=SAS REPLACE ;

OUTPUT UPPEREND CUMPCT SECUMPCT /FILENAME=HIST FILETYPE=SAS 

REPLACE;

If you change the first OUTPUT statement in the above program to

OUTPUT QTILE LOWQTILE UPQTILE /FILENAME=PCTILES FILETYPE=SAS 

REPLACE ;

SUDAAN will provide the upper and lower confidence limits based on the “test inversion” 

method of Francisco and Fuller. However, as mentioned earlier, this report does not use 

SUDAAN’s default method to generate confidence intervals for percentiles.

Step 2

Using SAS DATA steps to manipulate the output files from Step 1, find the value of the estimated 

cumulative distribution function that is less than or equal to p using the values of the cumulative 

percent produced by SUDAAN in the output file HIST: 

Save F (x ˆ j

) and the corresponding standard error (SE) estimate at F (x ˆ j) and proceed to step 3.

Step 3

Using p (the desired percentile) and the standard error of the estimate of F (x ˆ j), compute the 

95% confidence interval for p: (pL

, pU) as p+t

0.025,DFSE, where the degrees of freedom (DF) are 

the number of primary sampling units minus the number of strata and SE is the standard error 

from step 2. To get the appropriate degrees of freedom for each subgroup use the ATLEVEL1 and 

ATLEVEL2 options in SUDAAN’s PROC DESCRIPT to count up the number of strata and 

PSUs with valid data. This must be done in a separate call to PROC DESCRIPT than the one 

that calculates the percentiles because the HISTPCT statement is not available with ATLEVEL. 

Note: SAS (version 9.2) uses the empirical point estimate at the desired percentile, p = ˆ F (x ˆ j

), in 

order to calculate the 95% confidence interval as p ˆ +t

0.025,DFSE.

ˆ j p)x(F  ˆ 1j )x(F
476 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Step 4

Map the lower (pL) and upper (pU) confidence intervals of the empirical distribution function at 

the desired percentile using the inverse of the empirical distribution function (see Figure 2) and 

linear interpolation to get the confidence interval for the percentile of interest.

Let Lˆ p

 be the lower confidence limit of the estimated percentile and Uˆ p be the upper confidence 

limit of the estimated percentile. x1

, x2, ... xn are a rank ordered listing of the values as produced 

by SUDAAN using HISTPCT, such that x1

 is the minimum value and xn is the maximum value; 

then these can be found from the following expressions:

Figure 2

p

X

p

U

p

L

p

Analyte Value

 pU

 pL

  ˆ )x(F

1p

ˆ p)x(F

p ˆ )x(F

x

xx ˆ )x(F ˆ )x(F

p ˆ )x(F

x

x

Lˆ 1j

L

Lj

L 1

n

j1j

1j j

L j

j

1

p  



























 

 

  ˆ )x(F

1p

ˆ p)x(F

p ˆ )x(F

x

xx ˆ )x(F ˆ )x(F

p ˆ )x(F

x

x

Uˆ 1j

U

Uj

U 1

n

j1j

1j j

U j

j

1

p  



























 

 
Appendices 477

Commercial Software

PROC DESRIPT in SUDAAN (version 8.0 and higher) calculates confidence limits for the 

percentiles using the “test-inversion” method by Fransisco and Fuller, as noted in Step 1. 

PROC SURVEYMEANS (SAS version 9.1 and higher) can be used to obtain Woodruff like 

confidence intervals for percentiles. However, the SURVEYMEANS method differs slightly from 

the traditional Woodruff method as noted in Step 3.

References

Francisco CA, Fuller WA. Quantile estimation with a complex survey design. Annals Statist. 1991;19:454–469.

Korn EL, Graubard BI. Analysis of Health Surveys. Wiley: New York, 1999.

Kovar JG, Rao JNK, Wu CFL. Bootstrap and other methods to measure errors in survey estimated. Can J Statist. 

1988;16S:25–45.

Research Triangle Institute (2008). SUDAAN Language Manual, Release 10.0 Research Triangle Park, NC: Research 

Triangle Institute. 

Rogers JW. Estimating the variance of percentiles using replicate weights. Proceedings of the Section on Survey 

Research Methods. 2003.

Sitter RR, Wu C. A note on Woodruff confidence intervals for quantiles. Statist Probabil Letters. 2001;52:353–358.

Woodruff RS. Confidence intervals for medians and other position measures. J Am Statist Assoc. 1952;57:622–627. 

U.S. Centers for Disease Control and Prevention. NHANES Analytic guidelines, the Third National Health and 

Nutrition Examination Survey, NHANES III (1988–94). Hyattsville (MD): National Center for Health Statistics; 

October 1996 [cited 2008]. Available from: http://www.cdc.gov/nchs/data/nhanes/nhanes3/nh3gui.pdf.
478 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Appendix F

Limit of Detection Table

The table below presents the analytical limit of detection (LOD) for each indicator. The LOD is the level at 

which the measurement has a 95 percent probability of being greater than zero (Taylor 1987). For the same 

indicator, LOD values may change over time as a result of changes to analytical methods. This was the case 

for serum ferritin and urinary phytoestrogens. We used the highest LOD value when multi-year data were 

combined. The information provided in parentheses specifies what proportion of results was below the LOD 

for each indicator and survey cycle.

Indicator Units 1999-2000 2001-2002 2003-2004 2005-2006

Water-Soluble Vitamins

B Vitamins and Related Biochemical Compounds

Serum folate ng/mL 0.1 (0%) 0.1 (0%) 0.1 (0%) 0.1 (0%)

Red blood cell folate ng/mL 20 (0%) 20 (0%) 20 (< 1%) 20 (0%)

Serum pyridoxal-5’-phosphate nmol/L no data no data no data 0.3 (0%)

Serum 4-pyridoxic acid nmol/L no data no data no data 0.3 (0%)

Serum vitamin B12 pg/mL 20 (0%) 20 (0%) 20 (0%) 20 (0%)

Plasma homocysteine μmol/L 0.35 (0%) 0.35 (0%) 0.35 (0%) 0.35 (0%)

Plasma methylmalonic acid nmol/L 50 (1%) 50 (1%) 50 (< 1%) no data

Serum vitamin C μmol/L no data no data 0.68 (< 1%) 0.68 (< 1%)

Fat-Soluble Vitamins and Nutrients

Vitamins A and E and Carotenoids

Serum vitamin A (retinol) μg/dL 1.03 (0%) 1.03 (0%) no data 1.03 (< 1%)

Serum vitamin E (alpha-tocopherol) μg/dL 40.7 (0%) 40.7 (0%) no data 40.7 (0%)

Serum gamma-tocopherol μg/dL 10.7 (< 1%) 10.7 (< 1%) no data 10.7 (0%)

Serum alpha-carotene μg/dL no data 0.7 (9%) no data 0.7 (7%)

Serum trans-beta-carotene μg/dL no data 0.8 (< 1%) no data 0.8 (< 1%)

Serum cis-beta-carotene μg/dL no data 0.7 (52%) no data 0.7 (51%)

Serum beta-cryptoxanthin μg/dL no data 0.9 (< 1%) no data 0.9 (< 1%)

Serum lutein and zeaxanthin μg/dL no data 2.4 (< 1%) no data 2.4 (< 1%)

Serum trans-lycopene μg/dL no data 0.8 (< 1%) no data 0.8 (< 1%)

Serum total lycopene μg/dL no data no data no data 1.0 (< 1%)

Serum retinyl palmitate μg/dL 0.2 (16%) 0.2 (2%) no data 1.3 (22%)

Serum retinyl stearate μg/dL 0.5 (86%) 0.5 (87%) no data 0.7 (88%)

Serum 25-hydroxyvitamin D nmol/L no data 3.7 (0%) 3.7 (0%) 3.7 (0%)

Fatty Acids - Saturated

Plasma myristic acid (14:0) μmol/L no data no data 1.6 (0%) no data

Plasma palmitic acid (16:0) μmol/L no data no data 8.2 (0%) no data

Plasma stearic acid (18:0) μmol/L no data no data 23.7 (0%) no data

Plasma arachidic acid (20:0) μmol/L no data no data 0.6 (0%) no data

Plasma docosanoic acid (22:0) μmol/L no data no data 0.2 (0%) no data

Plasma lignoceric acid (24:0) μmol/L no data no data 0.1 (0%) no data
Appendices 479

Indicator Units 1999-2000 2001-2002 2003-2004 2005-2006

Fatty Acids - Monounsaturated

Plasma myristoleic acid (14:1n-5) μmol/L no data no data 0.1 (0%) no data

Plasma palmitoleic acid (16:1n-7) μmol/L no data no data 0.6 (0%) no data

Plasma cis-vaccenic acid (18:1n-7) μmol/L no data no data 0.3 (0%) no data

Plasm oleic acid (18:1n-9) μmol/L no data no data 5.2 (0%) no data

Plasma eicosenoic acid (20:1n-9) μmol/L no data no data 0.2 (0%) no data

Plasma docosenoic acid (22:1n-9) μmol/L no data no data 0.3 (3%) no data

Plasma nervonic acid (24:1n-9) μmol/L no data no data 0.4 (0%) no data

Fatty Acids - Polyunsaturated

Plasma linoleic acid (18:2n-6) μmol/L no data no data 2.2 (0%) no data

Plasma alpha-linolenic acid (18:3n-3) μmol/L no data no data 0.2 (0%) no data

Plasma gamma -linolenic acid (18:3n-6) μmol/L no data no data 0.1 (0%) no data

Plasma eicosadienoic acid (20:2n-6) μmol/L no data no data 0.1 (0%) no data

Plasma homo-gamma-linolenic acid (20:3n-6) μmol/L no data no data 0.2 (0%) no data

Plasma arachidonic acid (20:4n-6) μmol/L no data no data 0.3 (0%) no data

Plasma eicosapentaenoic acid (20:5n-3) μmol/L no data no data 0.1 (0%) no data

Plasma docosatetraenoic acid (22:4n-6) μmol/L no data no data 0.2 (0%) no data

Plasma docosapentaenoic acid (22:5n-3) μmol/L no data no data 0.2 (0%) no data

Plasma docosapentaenoic acid (22:5n-6) μmol/L no data no data 0.1 (0%) no data

Plasma docosahexaenoic acid (22:6n-3) μmol/L no data no data 0.1 (0%) no data

Trace Elements

Iron-Status Indicators

Serum ferritin ng/mL 1.1 (0%) 1.1 (0%) 3 (1%) 3 (1%)

Serum soluble transferrin receptor mg/L no data no data 0.5 (0%) 0.5 (0%)

Urinary iodine ng/mL no data 1.0 (0%) 1.0 (0%) 1.0 (0%)

Isoflavones and Lignans

Urinary genistein μg/L 0.3 (6%) 0.8 (< 1%) 0.3 (< 1%) 1.0 (< 1%)

Urinary daidzein μg/L 0.5 (1%) 1.6 (7%) 0.3 (< 1%) 0.4 (< 1%)

Urinary equol μg/L 3 (28%) 3.3 (30%) 0.3 (< 1%) 0.06 (< 1%)

Urinary O-desmethylangolensin μg/L 0.2 (25%) 0.4 (27%) 0.2 (7%) 0.2 (4%)

Urinary enterodiol μg/L 0.8 (8%) 1.5 (4%) 0.3 (1%) 0.04 (< 1%)

Urinary enterolactone μg/L 0.6 (2%) 1.9 (1%) 0.3 (< 1%) 0.1 (0%)

Acrylamide Hemoglobin Adducts

Acrylamide hemoglobin adduct pmol/g Hb no data no data 3 (< 1%) no data

Glycidamide hemoglobin adduct pmol/g Hb no data no data 4 (2%) no data

Reference

Taylor JK. Quality assurance of chemical measurements. Chelsea (MI): Lewis Publishing; 1987.
480 2nd National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population

Appendix G

Selected References of Descriptive NHANES Papers on 

Diet-and-Nutrition Biochemical Indicators

Water-Soluble Vitamins

Bailey RL, Mills JL, Yetley EA, Gahche JJ, Pfeiffer CM, Dwyer JT, et al. Unmetabolized serum folic acid and its 

relation to folic acid intake from diet and supplements in a nationally representative sample of adults aged >=60 y 

in the United States. Am J Clin Nutr. 2010;92:383–389.

Bailey RL, McDowell MA, Dodd KW, Gahche JJ, Dwyer JT, Picciano MF. Total folate and folic acid intake from 

foods and dietary supplements of US children aged 1–13 y. Am J Clin Nutr. 2010;92:353–358.

Bailey RL, Dodd KW, Gahche JJ, Dwyer JT, McDowell MA, Yetley EA, et al. Total folate and folic acid intake 

from foods and dietary supplements in the United States: 2003–2006. Am J Clin Nutr. 2010;91:231–237.

Bentley TGK, Willett WC, Weinstein MC, Kuntz KM. Population-level changes in folate intake by age, sex, and 

race/ethnicity after folic acid fortification. Am J Public Health. 2006;96:2040–2047.

Boulet SL, Yang Q, Mai C, Mulinare J, Pfeiffer CM. Folate status in women of childbearing age by race/ethnicity–

United States 1999–2000, 2001–2002, and 2003–2004. Morb Mortal Wkl Rep. 2007;55(51):1377–1380.

Dietrich M, Brown CJP, Block G. The effect of folate fortification of cereal-grain products on blood folate status, 

dietary folate intake and dietary folate sources among adult non-supplement users in the United States. J Am Coll 

Nutr. 2005;24:266–274.

Ganji V, Kafai MR. Hemoglobin and hematocrit values are higher and prevalence of anemia is lower in the 

post-folic acid fortification period than in the pre-folic acid fortification period in US adults. Am J Clin Nutr. 

2009;89:363–371.

Ganji V, Kafai MR. Demographic, lifestyle, and health characteristics and serum B vitamin status are determinants 

of plasma total homocysteine concentrations in the post-folic acid fortification period, 1999–2004. J Nutr. 

2009;139:345–352.

Ganji V, Kafai MR. Trends in serum folate, RBC folate, and circulating total homocysteine concentrations in the 

United States: analysis of data from National Health and Nutrition Examination Surveys, 1988–1994, 1999–2000, 

and 2001–2002. J Nutr. 2006;136:153–158.

Ganji V, Kafai MR. Population reference values for plasma total homocysteine concentrations in US adults after 

the fortification of cereals with folic acid. Am J Clin Nutr. 2006;84:989–994.

Ganji V, Kafai MR. Population references for plasma total homocysteine concentrations for US children and 

adolescents in the post-folic acid fortification era. J Nutr. 2005;135:2253–2256.

Ganji V, Kafai MR. Serum total homocysteine concentration determinants in non-Hispanic white, non-Hispanic 

black, and Mexican-American populations of the United States. Ethn Dis. 2004;14:476–482.

Ganji V, Kafai MR. Demographic, health, lifestyle, and blood vitamin determinants of serum total homocysteine 

concentrations in the Third National Health and Nutrition Examination Survey, 1988–1994. Am J Clin Nutr. 

2003;77:826–833.

Hamner HC, Mulinare J, Cogswell ME, Flores AL, Boyle CA, Prue CE, et al. Predicted contribution of folic acid 

fortification of corn masa flour to the usual folic acid intake for the US population: National Health and Nutrition 

Examination Survey, 2001–2004. Am J Clin Nutr. 2009;89:305–315.

McDowell MA, Lacher DA, Pfeiffer CM, Mulinare J, Picciano MF, Rader JI, et al. Blood folate levels: The latest 

NHANES results. NCHS data briefs, no 6. Hyattsville, MD: National Center for Health Statistics. 2008.

Morris MS, Jacques PF, Rosenberg IH, Selhub J. Circulating unmetabolized folic acid 5-methyltetrahydrofolate 

in relation to anemia, macrocytosis, and cognitive test performance in American seniors. Am J Clin Nutr. 

2010;91:1733–1744. 

Morris MS, Sakakeeny L, Jacques PF, Picciano MF, Selhub J. Vitamin B6 intake is inversely related to, and the 

requirement is affected by, inflammation status. J Nutr. 2010;140:103–110. 
Appendices 481

Morris MS, Picciano MF, Jacques PF, Selhub J. Plasma pyridoxal-5’-phosphate in the US population: the National 

Health and Nutrition Examination Survey, 2003–2004. Am J Clin Nutr. 2008;87:1446–1454.

Morris MS, Jacques PF, Rosenberg IH, Selhub J. Folate and vitamin B12 status in relation to anemia, macrocytosis, 

and cognitive impairment in older Americans in the age of folic acid fortification. Am J Clin Nutr. 2007;85:193–200.

Morris MS, Jacques PF, Rosenberg IH, Selhub J. Elevated serum methylmalonic acid concentrations are common 

among elderly Americans. J Nutr. 2002;132:2799–2803.

Must A, Jacques PF, Rogers G, Rosenberg IH, Selhub J. Serum total homocysteine concentrations in children and 

adolescents: results from the Third National Health and Nutrition Examination Survey (NHANES III). J Nutr. 

2003;133:2643–2649.

Pfeiffer CM, Osterloh JD, Kennedy-Stephenson J, Picciano MF, Yetley EA, Rader JI, et al. Trends in circulating 

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Trace Elements

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Isoflavones and Lignans 

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