LINUS PAULING INSTITUTE

NUTRITION AND THE IMMUNE SYSTEM
The immune system is constantly working to protect the body from infection,
injury, and disease.
OVERVIEW OF THE IMMUNE SYSTEM

The immune system consists of various organs, tissues,and cells located throughout the body.
WHITE BLOOD CELLS (WBCs)tonsils• The cells of the immune system• Made inside bone marrow• WBCs travel through the body inside lymph vessels, which
are in close contact with the bloodstream

lymph nodes

thymusTHERE ARE SEVERAL TYPES OF WBCsspleen
peyer’s patches

lymph vessels

NEUTROPHILSEngulf and destroy

MONOCYTES(MACROPHAGES)
Engulf and destroy

EOSINOPHILSFight parasiticinfections

BASOPHILS
Release histamine

LYMPHOCYTESAttack specificpathogens

PLASMA CELLS
Produceantibodies

bone marrow

THE IMMUNE SYSTEM PROVIDES THREE LEVELS OF DEFENSE AGAINST DISEASE-CAUSING ORGANISMS
1BARRIERS
Prevent entry• Skin and mucous
membranes• Stomach acid anddigestive enzymes• Beneficial bacteria thatlive in the colon (the gutmicrobiota)

2

INNATE IMMUNITY
General defense• WBCs called neutrophils
and macrophages engulf
and destroy foreign
invaders and damagedcells

3

ACQUIRED IMMUNITY
Specific defense• WBCs called T lymphocytes (Tcells) target and destroy infectedor cancerous cells• WBCs called B lymphocytes (Bcells) and plasma cells produce
antibodies that target and destroy
infected or cancerous cells

NUTRIENTS THAT SUPPORT IMMUNE FUNCTION
NUTRIENTRDA (ADULTS)

GOOD SOURCESEPA + DHA

No RDA (Advised to consume twoservings of oily fish/week)

herring 3 oz, 1.8 g
salmon 3 oz, 1.5 gsardines 3 oz, 1.2 g

Vitamin A*Men: 900 µg/day RAE

egg 1 large, 80 µg RAE
carrot** ½ cup raw, 534 µg RAE

Vitamin C*

Men: 90 mg/day

Women: 700 µg/day RAE

Women: 75 mg/day

sweet potato** ½ cup baked, 961 µg RAE
sweet red pepper 1 medium, 152 mg
kiwifruit 1 medium, 91 mg
strawberries 1 cup whole, 85 mg
pink salmon 3 oz, 370 IU

Vitamin D*

19-70 years: 600 IU/daysardines 3 oz, 164 IU

71 years and older: 800 IU/day

fortified milk 1 serving, 120 IU
sunshinealmonds 1 oz, 7 mg

Vitamin E*All adults: 15 mg/day

FolateAll adults: 400 µg/day DFE

lentils ½ cup cooked, 179 µg DFE
spinach ½ cup cooked, 131 µg DFE
enriched bread*** 1 slice, 84 µg DFE

Vitamin B12All adults: 2.4 µg/day

clams 3 oz, 84.1 µg
mackerel 3 oz, 16.1 µg

Vitamin B6

19-50 years: 1.3 mg/day
Men 51 years and older: 1.7 mg/day
Women 51 years and older: 1.5 mg/day

salmon 3 oz, 0.5 mg
turkey 3 oz, 0.7 mg
potato with skin 1 medium, 0.7 mg

Zinc

Men: 11 mg/day
Women: 8 mg/dayoysters 6 medium, 27-50 mg
beef 3 oz, 4-6 mg

Iron*

Men and women 51 years and older: 8 mg/day
Women 19-50 years: 18 mg/day

beef 3 oz, 1.6 mg
tuna 3 oz, 1.3 mg
lentils ½ cup cooked, 3.3 mg

CopperAll adults: 900 µg/day

oysters 6 medium, 2,397 µg
cashew nuts 1 oz, 622 µg
lentils 1 cup cooked, 497 µg

Selenium

All adults: 55 µg/day

tuna 3 oz, 92 µg
pork 3 oz, 32.5 µg
whole-wheat bread 1 slice, 8.2 µg

sunflower oil 1 T, 6 mg
avocado 1 whole, 2.7 mg

RDA = Recommended Dietary Allowance | RAE = retinol activity equivalents | DFE = dietary folate equivalents
IU = International Units | g = grams | mg = milligrams | µg = micrograms | oz = ounce(s) | T = Tablespoon*Underconsumed by eating the typical American diet. Iron underconsumed by adolescent females and pregnant women only**A source of provitamin A carotenoids***A source of folic acid, the synthetic form of folate

FOR SOME NUTRIENTS, GETTING MORE THAN THE RDA MIGHT
BE OF FURTHER BENEFIT
VITAMIN C
Routine supplementation withvitamin C (0.25 to 2 g/day)
reduces the occurrence of thecommon cold in individuals
undergoing heavy physical stress(marathon runners, skiers, andsoldiers in subarctic conditions).

Routine supplementation withvitamin C slightly reduces theduration of the common cold.

The LPI recommends a daily intake
of at least 400 mg of vitamin C for
generally healthy adults.

Vitamin C
400 mg/day

CVITAMIN D
Low vitamin D status is linked to a higher risk of upper respiratory tract infections and some autoimmune
disorders. Supplementation with vitamin D reduces the risk of acute respiratory tract infection.

Vitamin D
2,000 IU

DThe LPI recommends 2,000 IU (50 µg) of supplemental vitamin D daily
for generally healthy adults.

SOURCES
Micronutrient Information Center• lpi.oregonstate.edu/mic/health-disease/immunity-in-brief• lpi.oregonstate.edu/mic/health-disease/immunity© 2018 Linus Pauling Institute