Effects of dairy food supplements on bone mineral density in teenage girls Calcium intake influences the association of protein intake with rates of bone loss in elderly men and women. Calcium supplementation provides an extended window of opportunity for bone mass accretion after menarche. Dietary acid load is associated with lower bone mineral density in men with low intake of dietary calcium. Bone mineralization in children and adolescents with a milk allergy. The effect of calcium supplementation and tanner stage on bone density, content and area in teenage women Effect of habitual dietary calcium intake on calcium supplementation in 12-14-y-old girls. Effect of milk and calcium supplementation on bone density and bone turnover in pregnant Chinese women: a randomized controlled trail Treatment with alendronate plus calcium, alendronate alone, or calcium alone for postmenopausal low bone mineral density Calcium-enriched foods and bone mass growth in prepubertal girls: a randomized, double-blind, placebo-controlled trial. Effect of calcium or 25OH vitamin D3 dietary supplementation on bone loss at the hip in men and women over the age of 60. Calcium supplementation and bone mineral density in adolescent girls. Dairy intakes affect bone density in the elderly. Effect of calcium supplementation on bone mineral accretion in gambian children accustomed to a low-calcium diet. Beneficial effect of soy isoflavones on bone mineral content was modified by years since menopause, body weight, and calcium intake: a double-blind, randomized, controlled trial Calcium supplementation and bone mineral density in females from childhood to young adulthood: a randomized controlled trial. Appendicular bone mass in children with a high prevalence of low dietary calcium intakes. A 1-y walking program and increased dietary calcium in postmenopausal women: effects on bone. The effect on behavior and bone mineral density of individualized bone mineral density feedback and educational interventions in premenopausal women: a randomized controlled trial [NCT00273260] Cumulative effects of calcium supplementation and physical activity on bone accretion in premenarchal children: a double-blind randomised placebo-controlled trial. Bone mineral contents and plasma osteocalcin concentrations of Gambian children 12 and 24 mo after the withdrawal of a calcium supplement. Vitamin D Is a Major Determinant of Bone Mineral Density at School Age Vitamin D supplementation and bone mineral density in early postmenopausal women.
Summary Background Bone mineral density ( BMD ) is largely genetically determined and this influence is most powerful in the period of rapid skeletal development in childhood and late adolescence but environmental factors such as exercise and dietary calcium intake may influence up to 20 % . Aims of the study The aims of the study were to examine healthy late adolescent females for the effects and benefits of a high calcium intake from dairy product foods on bone mineral density , body composition , lipids and biochemistry . The secondary aim is determine whether a high intake of dairy product foods in the diet is acceptable for this age group long term . Methods Ninety-one teenage girls who participated in a two-year r and omised controlled study on the effect of dairy food supplementation on dietary patterns , body composition and bone density in post-pubertal teenage girls were approached one year after the cessation of the study to determine the effects of the cessation of dairy supplements on bone mineral density , dietary habits , biochemical markers , body composition and blood lipids . Bone mineral density and bone mineral content were assessed at the hip , spine and total body . Anthropometric data were collected , and exercise , Tanner , dietary assessment , preference and compliance question naires were administered . Lipid profiles , hydroxyproline excretion and urinary calcium and sodium excretion measurements were performed . Results There were no significant differences between the 2 groups for height , weight , lean and fat mass . The supplemented group had significantly higher calcium , phosphorus and protein intake during the supplementation period ( p<0.001 ) . No differences were seen between the groups 12 months after supplementation finished . There were no significant differences in exercise level , preference or acceptability of dairy products or in the lipids and bone markers between baseline the end of supplementation and 1 year follow-up . There was a significant increase in trochanter ( 4.6 % ) , lumbar spine ( 1.5 % ) and femoral neck ( 4.8 % ) BMD ( p<0.05 ) in the high calcium group at the end of supplementation . There was an increase in bone mineral content at the trochanter ( p<0.05 ) and lumbar spine ; however the latter was not statistically significant , in the high calcium group at the end of supplementation . There was no difference in vertebral height or width at any stage of the study , indicating no influence on bone size . Conclusions In this 3 year study ( 2 years of supplementation , 1 year follow-up ) , teenage girls , aged 15–18 years , were able to significantly increase their BMD at the trochanter , femoral neck and lumbar spine when supplemented with dairy product foods to a mean calcium intake of 1160 mg/d . There was also an effect seen on the BMC particularly at the trochanter and to a lesser extent at the lumbar spine . The dietary calcium intake achieved did not adversely affect body weight , fat and lean mass or blood lipid profiles . Twelve months after the supplementation finished the girls had returned to their baseline diet , indicating self- selection of a high dairy product diet may be hard to achieve BACKGROUND There is currently no consensus on the effect of dietary protein intake on the skeleton , but there is some indication that low calcium intakes adversely influence the effect of dietary protein on fracture risk . OBJECTIVE The objective of the present study was to determine whether supplemental calcium citrate malate and vitamin D influence any associations between  protein intake and change in bone mineral density ( BMD ) . DESIGN Associations between protein intake and change in BMD were examined in 342 healthy men and women ( aged > or = 65 y ) who had completed a 3-y , r and omized , placebo-controlled trial of calcium and vitamin D supplementation . Protein intake was assessed at the midpoint of the study with the use of a food-frequency question naire and  BMD  was assessed every 6 mo by dual-energy X-ray absorptiometry . RESULTS The mean ( + /-SD ) protein intake of all subjects was 79.1 + /- 25.6 g/d and the mean total calcium intakes of the supplemented and placebo groups were 1346 + /- 358 and 871 + /- 413 mg/d , respectively . Higher protein intake was significantly associated with a favorable 3-y change in total-body BMD in the supplemented group ( in a model containing terms for age , sex , weight , total energy intake , and dietary calcium intake ) but not in the placebo group . The pattern of change in femoral neck BMD with increasing protein intake in the supplemented group was similar to that for the total body . CONCLUSION Increasing protein intake may have a favorable effect on change in BMD in elderly subjects supplemented with calcium citrate malate and vitamin BACKGROUND High calcium intakes during adolescence may increase bone acquisition . The magnitude of the effect of dietary calcium supplementation and the timing of its administration to achieve significant effects on bone health are still incompletely defined . OBJECTIVE The objective of this study was to assess the effect of calcium supplementation on bone mass accretion in postmenarcheal adolescent girls with low calcium intakes . DESIGN A double-blind , placebo-controlled calcium supplementation study was implemented . One hundred girls with a mean ( + /- SD ) age of 14 + /- 0.5 y with habitual calcium intakes < 800 mg/d completed a 12-mo protocol . The treatment group received a daily supplement containing 1000 mg elemental calcium .  Bone mineral density ( BMD ) and bone mineral content ( BMC ) of the total body , lumbar spine , and femoral neck were determined at inclusion , 6 mo , and 12 mo . Also measured were serum concentrations of biochemical markers of bone turnover ( osteocalcin and deoxypyridinoline ) , parathyroid hormone , and vitamin D. RESULTS The calcium-supplemented group had greater accretion of total-body BMD and lumbar spine BMD but not BMC than did the control group . Calcium supplementation appeared selectively beneficial for girls who were 2 y postmenarcheal . Calcium supplementation significantly decreased bone turnover and decreased serum parathyroid hormone concentrations . CONCLUSION Calcium supplementation of postmenarcheal girls with low calcium intakes enhances bone mineral acquisition , especially in girls > 2 y past the onset of menarche High dietary acid load ( DAL ) may be detrimental to bone mineral density ( BMD ) . The objectives of the study were to : ( 1 ) evaluate the cross-sectional relation between DAL and BMD ; and ( 2 ) determine whether calcium intake modifies this association . Men ( n = 1218 ) and women ( n = 907 ) aged ≥60 years were included from the National Health and Nutrition Examination Survey 2005 - 2008 .  Nutrient intake from 2 , 24-hour recalls was used to calculate net endogenous acid production ( NEAP ) and potential renal acid load  ( PRAL ) ( mEq/d ) . PRAL was calculated from dietary calcium ( PRALdiet ) and diet + supplemental calcium ( PRALtotal ) . Tests for linear trend in adjusted mean BMD of the hip and lumbar spine were performed across energy-adjusted NEAP and PRAL quartiles . Modification by calcium intake ( dietary or total ) above or below 800 mg/d was assessed by interaction terms . Overall , mean age was 69 ± 0.3 years . Among women , there was no association between NEAP and BMD  . PRALdiet was positively associated with proximal femur BMD ( p trend = 0.04 ) . No associations were observed with PRALtotal at any BMD site ( p range , 0.38 - 0.82 ) . Among men , no significant associations were observed between BMD and NEAP or PRAL . However , an interaction between PRALdiet and calcium intake was observed with proximal femur BMD ( p = 0.08 ) . An inverse association between PRALdiet and proximal femur BMD was detected among men with < 800 mg/d dietary calcium ( p = 0.02 ) ; no associations were found among men with ≥800 mg/d ( p = 0.98 ) . A significant interaction with PRALtotal was not observed . In conclusion , when supplemental calcium is considered , there is no association between DAL and  BMD among adults . Men with low dietary calcium showed an inverse relation with PRAL at the proximal femur ; in women no interaction was observed . This study highlights the importance of calcium intake in counteracting the adverse effect of DAL on bone health . Further research should determine the relation between DAL and change in BMD with very low calcium intake To evaluate the correlation between dietary calcium intake and mineralization of the immature skeleton 55 children and adolescents aged 5 - 14 years ( mean , 9.5 years ) with a positive radioallergosorbent test ( RAST ) for serum antibodies to cow 's milk protein were evaluated .  Bone mineral density ( BMD ) in the lumbar spine and proximal femurs were measured by dual energy X-ray absorptiometry . BMD at each site for each subject was converted to an age-adjusted Z score based on our own series of 95 normal pediatric controls .  Calcium intake was determined using a detailed food frequency question naire administered by a nutritionist during a 30 - 40-min interview . Dietary adjustments to the condition varied and result ed in a wide range of calcium intakes . Calcium supplements were taken by 22 % of the subjects and were included in the determination of daily calcium intake . The group of 55 subjects was divided into quartiles based on calcium intake ( mean + /- S.E mg calcium/day ) : Group 1 , 409 + /- 21 , Group 2 , 663 + /- 16 , Group 3 , 950 + /- 32 , Group 4 , 1437 + /- 124 . Bone density Z scores in the proximal femur serially increased across the calcium intake groups ( mean + /- S.E. ) : Group 1 , -0.16 + /- 0.31 ; Group 2 , 0.05 + /- 0.33 ; Group 3 , 0.44 + /- 0.24 ; Group 4 , 0.79 + /- 0.41 ( P = 0.03 ) . A similar pattern was found with lumbar spine BMD Z scores : Group 1 , -0.16 + /- 0.27 ; Group 2 , 0.10 + /- 0.21 ; Group 3 , 0.18 + /- 0.20 ; Group 4 , 0.30 + /- 0.25 ( P = 0.05 ) . These data add further to the evidence that dietary calcium intake is important for optimal mineralization of the growing skeleton One hundred and twelve Caucasian girls , 11.9±0.5 years of age at entry , were r and omized into a 24-month , double-masked , placebo-controlled trial to determine the effect of calcium supplementation on bone mineral content , bone area and bone density . Supplementation was 500 mg calcium as calcium citrate malate ( CCM ) per day . Controls received placebo pills , and compliance of both groups averaged 72 % . Bone mineral content , bone mineral area and bone mineral density of the lumbar spine and total body were measured by dual energy X-ray absorptiometry ( DXA ) . Calcium intake from dietary sources averaged 983 mg/day for the entire study group . The supplemented group received , on average , an additional 360 mg calcium/day from CCM . At baseline and after 24 months , the two groups did not differ with respect to anthropometric measurements , urinary reproductive hormone levels or any measurement of pubertal progression . The supplemented group had greater increases of total body bone measures : content 39.9 % versus 35.7 % ( p=0.01 ) , area 24.2 % versus 22.5 % ( p=0.15 ) and density 12.2 % versus 10.1 % ( p=0.005 ) . Region-of-interest analyses showed that the supplemented group had greater gains compared with the control group for bone mineral density , content and area . In particular , in the lumbar spine and pelvis , the gains made by the supplemented group were 12%–24 % greater than the increases made by the control group . Bone acquisition rates in the two study groups were further compared by subdividing the groups into those with below- or above-median values for Tanner score and dietary calcium intake . In subjects with below-median Tanner scores , bone acquisition was not affected by calcium supplementation or dietary calicum level . However , the calcium supplemented subjects with above-median Tanner had higher bone acqusition rates than the placebo group with above-median Tanner scores . Relative to the placebo group , the supplemented group had increased yearly gains of bone content , area and density which represented about 1.5 % of adult female values . Such increases , if held to adult skeletal maturity , could provide protection against future risk of osteoporotic fractures BACKGROUND There is no agreement on how much calcium young girls need for optimal bone mineralization . OBJECTIVE We evaluated whether the effect of calcium supplementation on whole-body bone mineral accretion depends on habitual calcium intake . DESIGN This was a r and omized , double-blind , placebo-controlled , 1-y calcium intervention study of girls aged 12 - 14 y selected from a larger group according to habitual calcium intake : subgroup A ( n = 60 ) habitually consumed 1000 - 1307 mg/d ( 40th-60th percentile ) , and subgroup B ( n = 53 ) habitually consumed < 713 mg/d ( < 20th percentile ) . The girls from each subgroup were r and omly assigned to receive either 500 mg Ca/d or placebo .  Whole-body bone mineral content ( BMC ) , bone area ( BA ) , bone mineral density ( BMD ) , and BMC adjusted for BA , height , and weight ( size-adjusted BMC ) were measured at baseline and after 1 y. RESULTS There was no significant effect modification of baseline habitual calcium intake on the relation between calcium supplementation and height , weight , BMC , size-adjusted BMC , BA , BMD , or alkaline phosphatase .  Calcium supplementation had an effect on BMD ( 0.8 % ; P = 0.049 ) and tended to show signs of an effect on size-adjusted BMC ( 0.5 % ; P = 0.08 ) . CONCLUSION A modest effect of calcium supplementation on BMD was shown . However , the effect was independent of habitual calcium intake Objective Calcium dem and is increased during pregnancy . However , few r and omized controlled trials examined the effects of calcium supplementation on bone mass during pregnancy . This study determined effects of calcium and milk supplementation on maternal bone mineral density ( BMD ) and bone turnover in pregnant Chinese women with habitual low calcium intake . Methods In this r and omized controlled trial , 36 Chinese pregnant women ( 24–31 years , 18 gestational weeks ) were r and omly assigned to the following three arms ( 12 each ) : I , usual diet ; II , “ I ” + 45 g milk powder ( containing 350 mg calcium ) ; or III , “ II ” + 600 mg calcium/day from gestational age of 20 weeks to 6 weeks post-partum ( PP ) . BMD was measured post-treatment using dual-energy X-ray absorptiometry . Dietary intakes , 24-h urinary calcium , bone resorption ( urinary hydroxyproline ) and formation ( serum osteocalcin ) biomarkers were examined at the gestational age of 20 and 34 weeks , and 6 weeks PP . Results A dose-dependent relationship was observed between calcium intake and BMDs . The BMD values were significantly higher in subjects with calcium and milk supplementation  than those in the controls at the whole body and spine ( p < 0.05 ) but not at the hip sites . We found significant decreases in changes of urinary hydroxyproline , and significant increases in serum osteocalcin during the intervention period in the calcium/milk intervention groups than those in the control group ( all p < 0.05 ) . Conclusion Calcium/milk supplementation during pregnancy is associated with greater BMD at the spine and whole body and suppresses bone resorption in Chinese women with habitual low calcium intake ABSTRACT Objective : Bisphosphonates such as alendronate are widely used for postmenopausal osteoporosis . Supplemental calcium is also generally recommended . This trial directly compares alendronate to supplemental calcium and examines the effect of calcium supplementation on alendronate treatment . Methods : This 2-year , r and omized , double-blind , multicenter trial enrolled healthy , postmenopausal women with low bone mineral density ( BMD ) . Patients with a dietary calcium intake ≥ 800 mg/day received daily vitamin D 400 IU and alendronate 10 mg/calcium-placebo , alendronate 10 mg/elemental calcium 1000 mg , or alendronate-placebo/calcium 1000 mg ( 2:2:1 ) . Endpoints included BMD , bone turnover markers ( BTMs ) , and adverse events . Results : R and omized patients ( N = 701 ) were an average of 20.4 years postmenopausal . After 24 months , increases in lumbar spine BMD differed significantly between patients receiving calcium alone ( 0.8 % ) and either alendronate alone ( 5.6 % ) or alendronate + calcium ( 6.0 % ) ( p < 0.001 ) . Significant differences were also seen at the trochanter and femoral neck ( p < 0.001 ) . BTMs were significantly lower with alendronate-containing treatments than calcium alone ( p < 0.001 ) . Addition of calcium supplementation to alendronate did not significantly increase BMD  compared to alendronate alone ( p = 0.29 to 0.97 ) , but did result in a statistically significant , though small , additional reduction in urinary NTx . Adverse events were similar among treatment groups . Limitations include no assessment of vitamin D levels and a discontinuation rate of approximately 30 % , although discontinuation rates were similar among treatment groups . Conclusions : In postmenopausal women with a daily intake of ≥ 800 mg calcium and 400 IU vitamin D , 24-month treatment with alendronate 10 mg daily with or without calcium 1000 mg result ed in significantly greater increases in BMD and reduction of bone turnover than supplemental calcium alone . Addition of supplemental calcium to alendronate treatment had no effect on BMD and result ed in a small , though statistically significant , additional reduction in NTx High calcium intake during childhood has been suggested to increase bone mass accrual , potentially result ing in a greater peak bone mass . Whether the effects of calcium supplementation on bone mass accrual vary from one skeletal region to another , and to what extent the level of spontaneous calcium intake may affect the magnitude of the response has , however , not yet been clearly established . In a double-blind , placebo-controlled study , 149 healthy prepubertal girls aged 7.9+/-0.1 yr ( mean+/-SEM ) were either allocated two food products containing 850 mg of calcium ( Ca-suppl . ) or not ( placebo ) on a daily basis for 1 yr . Areal bone mineral density ( BMD ) , bone mineral content ( BMC ) , and bone size were determined at six sites by dual-energy x-ray absorptiometry . The difference in BMD gain between calcium-supplemented ( Ca-suppl . ) and placebo was greater at radial ( metaphysis and diaphysis ) and femoral ( neck , trochanter , and diaphyses ) sites ( 7 - 12 mg/cm2 per yr ) than in the lumbar spine ( 2 mg/cm2 per yr ) . The difference in BMD gains between Ca-suppl . and placebo was greatest in girls with a spontaneous calcium intake below the median of 880 mg/d . The increase in mean BMD of the 6 sites in the low-calcium consumers was accompanied by increased gains in mean BMC , bone size , and statural height . These results suggest a possible positive effect of calcium supplementation on skeletal growth at that age . In conclusion , calcium-enriched foods significantly increased bone mass accrual in prepubertal girls , with a preferential effect in the appendicular skeleton , and greater benefit at lower spontaneous calcium intake Dietary supplements that prevent bone loss at the hip and that can be applied safely in the elderly are likely to reduce hip fractures . A daily dietary supplement of 750 mg calcium or 15 microg 25OH vitamin D3 on bone loss at the hip and other sites , bone turnover and calcium-regulating hormones were studied over 4 yr in elderly volunteers using a r and omized , double-blind , placebo-controlled trial . Bone mineral density ( BMD ) was measured by dual x-ray absorptiometry and bone structure by radiographs . Calcium biochemistry and bone turnover markers were measured in blood and urine . The 316 women entering the trial had a mean age of 73.7 yr and the 122 men of 75.9 yr . Baseline median calcium intake was 546 mg/day , and median serum 25OH vitamin D3 was 59 nmol/L. On placebo , loss of BMD at total hip was 2 % and femoral medulla expansion was 3 % over 4 yr . Calcium reduced bone loss , secondary hyperparathyroidism , and bone turnover . 25OH vitamin D3 was intermediate between placebo and calcium . Fracture rates and drop-out rates were similar among groups , and there were no serious adverse events with either supplement . A calcium supplement of 750 mg/day prevents loss of BMD , reduces femoral medullary expansion , secondary hyperparathyroidism , and high bone turnover . A supplement of 15 microg/day 25OH vitamin D3 is less effective , and because its effects are seen only at low calcium intakes , suggests that its beneficial effect is to reverse calcium insufficiency OBJECTIVE To evaluate the effect of calcium supplementation on bone acquisition in adolescent white girls . DESIGN A r and omized , double-blind , placebo-controlled trial of the effect of 18 months of calcium supplementation on bone density and bone mass . SUBJECTS Ninety-four girls with a mean age of 11.9 + 0.5 years at study entry . SETTING University hospital in a small town . INTERVENTIONS Calcium supplementation , 500 mg/d calcium as calcium citrate malate ; controls received placebo pills . MAIN OUTCOME MEASURES Bone mineral density and bone mineral content of the lumbar spine and total body were measured by dual-energy x-ray absorptiometry and calcium excretion from 24-hour urine specimens . RESULTS Calcium intake from dietary sources averaged 960 mg/d for the entire study group . The supplemented group received , on average , an additional 354 mg/d of calcium . The supplemented group compared with the placebo group had greater increases of lumbar spine bone density ( 18.7 % vs 15.8 % ; P = .03 ) , lumbar spine bone mineral content ( 39.4 % vs 34.7 % ; P = .06 ) , total body bone mineral density ( 9.6 % vs 8.3 % ; P = .05 ) , and 24-hour urinary calcium excretion ( 90.4 vs 72.9 mg/d ; P = .02 ) , respectively . CONCLUSIONS Increasing daily calcium intake from 80 % of the recommended daily allowance to 110 % via supplementation with calcium citrate malate result ed in significant increases in total body and spinal bone density in adolescent girls . The increase of 24 g of bone gain per year among the supplemented group translates to an additional 1.3 % skeletal mass per year during adolescent growth , which may provide protection against future osteoporotic fracture BACKGROUND Race and sex differences in the effect of diet on bone mineral density ( BMD ) at the hip in the elderly are unknown . OBJECTIVES This study related cross-sectional nutrient and dairy product consumption to hip BMD in white and black men and women aged > 60 y and evaluated the influence of nutrient and dairy product consumption on changes in BMD in a white cohort participating in a calcium , vitamin D , or placebo trial . DESIGN The Health Habits and History Question naire was used in 289 white women and 116 white men who participated in the trial and in 265 black women and 75 black men to predict total hip and femoral neck BMD or  changes in BMD . RESULTS Blacks had higher calcium intakes than did whites ( 700 and 654 mg/d , respectively ; P = 0.0094 ) , and men had higher calcium intakes than did women ( 735 and 655 mg/d , respectively ; P = 0.0007 ) . For men , the correlation between total hip BMD and dairy calcium intake after adjustment for age , race , and weight was 0.23 ( P < 0.005 ) ; this relation was not significant in women ( r = 0.02 , P = 0.12 ) . Similar results were found for femoral neck BMD . In the longitudinal study , calcium supplementation reduced bone loss from the total hip and femoral neck in those who consumed < 1.5 servings of dairy products/d and were < 72 y old . CONCLUSIONS Cross-sectional results indicated that higher dairy product consumption is associated with greater hip BMD in men , but not in women . Calcium supplementation protected both men and women from bone loss in the longitudinal study of whites BACKGROUND Rural Gambian children have poor growth , delayed puberty , a low bone mineral content , and a low calcium intake . OBJECTIVE We investigated the effect of a calcium supplement on bone mineral accretion in rural Gambian children . DESIGN A r and omized , double-blind , placebo-controlled study was conducted in 160 children ( 80 boys , 80 girls ) aged 8.3 - 11.9 y.  Bone mineral content ( BMC ) , bone mineral density ( BMD ) , and BMC adjusted for bone width , body weight , and height ( size-adjusted BMC ) were measured at the midshaft and distal radius . Each child received either 1000 mg Ca/d ( as calcium carbonate ) or a placebo 5 d/wk for 12 mo . Supplementation increased calcium intake from 342 to 1056 mg/d ( 8.6 to 26.4 mmol/d ) . RESULTS Calcium supplementation result ed in a higher BMC , BMD , and size-adjusted BMC ( & xmacr ; difference + /- SE ) : midshaft radius- BMC ( 3.0 + /- 1.4 % ; P = 0.034 ) , BMD ( 4.5 + /- 0.9 % ; P < /= 0.0001 ) , and size-adjusted BMC ( 4.6 + /- 0.9 % ; P < /= 0.0001 ) ; distal radius- BMC ( 8 . 4 + /- 3.2 % ; P = 0.009 ) , BMD ( 7.0 + /- 2.7 % ; P = 0.011 ) , and size-adjusted BMC ( 5.5 + /- 2.7 % ; P = 0.042 ) . Supplementation had no significant effect on height , weight , or bone width at the midshaft radius or distal radius . At the end of the study , the calcium group had a significantly lower mean plasma osteocalcin concentration than the placebo group after adjustment for baseline concentration , sex , and pubertal status ( -21.9 + /- 6.5 % ; P = 0.001 ) . CONCLUSIONS Increased calcium intake result ed in increased bone mineral status , possibly in association with a decreased bone remodeling space . Further studies are needed to determine whether an increased calcium intake has long-term benefits in Gambian children Objective : Many studies have shown that soy isoflavones have an effect in preventing estrogen-related bone loss , but no data reported whether such an effect could be influenced by other important factors affecting bone loss . This study examines whether the associations between isoflavone supplementation and rates of change in bone mineral content ( BMC ) could be modified by years since menopause ( YSM ) , body weight ( BW ) , and dietary calcium intake in postmenopausal Chinese women aged 48 to 62 years . Design : A group of 203 eligible women were r and omly assigned to three treatment groups : placebo ( daily dose of 0 mg isoflavones + 500 mg calcium , n = 67 ) , mid-dose ( 40 mg isoflavones + 500 mg calcium , n = 68 ) ; and high-dose ( 80 mg isoflavones + 500 mg calcium , n = 68 ) . Bone mineral density ( BMD ) and BMC at the whole body , spine , and hip were measured by dual-energy x-ray absorptiometry at baseline and posttreatment after 1 year . YSM , BW , and dietary calcium intake stratified analyses were performed to evaluate whether the associations between isoflavones  supplementation and BMC change rates were varied with these factors . Results : Both univariate and multivariate analyses observed significant favorable effect of isoflavone supplementation on rates of change in BMC at the total hip and trochanter among later postmenopausal women ( > 4 y ) , in women with lower BW ( ≤median , 55.5 kg ) , or among women with lower level of calcium intake ( ≤median , 1095 mg/d ) . Conclusions : The independent effect of soy on the maintenance of hip BMC is more marked in women in later menopause or those with lower BW or calcium intake BACKGROUND Short-term studies established that calcium influences bone accretion during growth . Whether long-term supplementation influences bone accretion in young adults is not known . OBJECTIVE This study evaluated the long-term effects of calcium supplementation on bone accretion among females from childhood to young adulthood . DESIGN A 4-y r and omized clinical trial recruited 354 females in pubertal stage 2 and optionally was extended for an additional 3 y. The mean dietary calcium intake of the participants over 7 y was approximately 830 mg/d ;  calcium-supplemented persons received an additional approximately 670 mg/d . Primary outcome variables were distal and proximal radius bone mineral density ( BMD ) , total-body BMD ( TBBMD ) , and metacarpal cortical indexes . RESULTS Multivariate analyses of the primary outcomes indicated that  calcium-supplementation  effects vary over time . Follow-up univariate analyses indicated that all primary outcomes were significantly larger in the supplemented group than in the placebo group at the year 4 endpoint . However , at the year 7 endpoint , this effect vanished for TBBMD and distal radius BMD . Longitudinal models for TBBMD and proximal radius BMD , according to the time since menarche , showed a highly significant effect of supplementation during the pubertal growth spurt and a diminishing effect thereafter . Post hoc stratifications by compliance-adjusted total calcium intake and by final stature or metacarpal total cross-sectional area showed that calcium effects depend on compliance and body frame . CONCLUSIONS Calcium supplementation significantly influenced bone accretion  in young females during the pubertal growth spurt . By young adulthood , significant effects remained at metacarpals and at the forearm of tall persons , which indicated that the calcium requirement for growth is associated with skeletal size . These results may be important for both primary prevention of osteoporosis and prevention of bone fragility fractures during growth We have previously documented evidence of dietary calcium deficiency in black children living in a rural community in the eastern part of South Africa . The present study determined the bone mass of the distal one-third of the radius in a r and om sample of children living in the same community and compared their bone mass measurements with those of black children living in a similar rural community but without evidence of dietary calcium deficiency . Further , factors ( weight , height , serum corrected total calcium , phosphorus , and alkaline phosphatase [ ALP ] ) that might influence appendicular bone mass were assessed and correlated with the bone mass measurements . A r and om sample of 306 boys and 345 girls between the ages of 1 and 20 years were included in the study .  Hypocalcemia was found in 6.5 % of the boys and 5 % of the girls , while elevated ALP values were recorded in 20 and 26 % of the boys and girls , respectively . After adjusting for differences in age , weight , and height , bone mineral density ( BMD ) and bone mineral apparent density ( BMAD ) were significantly lower and bone width ( BW ) greater in study than control children . In a stepwise regression analysis , weight and /or height accounted for the majority of the observed variance in BMC , BW , and BMD ; however , a significant effect of serum calcium ( positively ) and ALP ( negatively ) on BMC and BMD was also found . In boys , but not girls , serum ALP also had a positive effect on BW.BMAD was negatively correlated to ALP and positively correlated to serum calcium in both boys and girls . Those children with hypocalcemia or elevated ALP levels had significantly lower BMC , BMD , and BMAD and a trend toward greater BW than children with normal biochemistry . The findings suggest that low dietary calcium intake may have a detrimental effect on appendicular bone density in rural black children . Whether or not these effects are disadvantageous in the long-term is not known The effects of a supervised 1-y walking program and increased dietary calcium ( milk supplement , 831 mg/d , vs placebo drink , 41 mg/d ) on bones were examined in 36 postmenopausal women ( 60.2 + /- 6.5 y ) .  Trabecular bone-mineral density ( BMD ) of the lumbar spine ( L1-L3 ) , measured by computed tomography , increased by 0.5 % in exercising women ( n = 18 ) and decreased by 7.0 % in sedentary women ( n = 18 ; P = 0.02 ) . Femoral-neck BMD measured by dual-photon absorptiometry ( DPA ) increased by 2.0 % in women consuming high dietary calcium ( n = 18 ) and decreased by 1.1 % in those on moderate calcium intake ( n = 18 ; P = 0.001 ) . Neither exercise nor  dietary calcium  had an effect on lumbar spine ( L2-L4 ) measured by DPA , distal radius measured by single-photon absorptiometry , or total body calcium measured by in vivo neutron activation . The varying proportions and rates of turnover of trabecular and cortical bone from one site to another suggest that exercise and high dietary calcium may preferentially alter bone density at different skeletal sites Background Limited information is available on ways to influence osteoporosis risk in premenopausal women . This study tested four hypotheses regarding the effects of individualized bone density ( BMD ) feedback and different educational interventions on osteoporosis preventive behavior and BMD in pre-menopausal women , namely : that women are more likely to change calcium intake and physical activity if their BMD is low ; that group education will be more efficacious at changing behavior than an information leaflet ; that BMD feedback and group education have independent effects on behavior and BMD ; and , that women who improve their physical activity or calcium intake will have a change in bone mass over 2 years that is better than those who do not alter their behavior . Methods We performed a 2-year r and omized controlled trial of BMD feedback according to T-score and either an osteoporosis information leaflet or small group education in a population -based r and om sample of 470 healthy women aged 25–44 years ( response rate 64 % ) . Main outcome measures were dietary calcium intake , calcium supplement use , smoking behavior , physical activity , endurance fitness , lower limb strength and BMD . We used paired t-tests , one-way ANOVA and linear regression techniques for data analysis . Results Women who had feedback of low BMD had a greater increase in femoral neck BMD than those with normal BMD ( 1.6 % p.a . vs. 0.7 % p.a . , p = 0.0001 ) , but there was no difference in lumbar spine BMD change between these groups ( 0.1 % p.a . vs. 0.08 % p.a . , p = 0.9 ) . Both educational interventions had similar increases in femoral neck BMD ( Leaflet = + 1.0 % p.a . , Osteoporosis self-management course = + 1.3 % p.a . , p = 0.4 ) . Femoral neck BMD change was only significantly associated with starting calcium supplements ( 1.3 % p.a , 95%CI + 0.49 , + 2.17 ) and persistent self-reported change in physical activity levels ( 0.7 % p.a . , 95%CI + 0.22 , + 1.22 ) . Conclusion Individualized BMD feedback combined with a minimal educational intervention is effective at increasing hip but not spine bone density in premenopausal women . The changes in behavior through which this was mediated are potentially important in the prevention of other diseases , thus measuring BMD at a young age may have substantial public health benefits , particularly if these changes are sustained High calcium intake combined with physical activity during childhood have been shown to improve bone mass accrual and bone mineral density . Our aim was to study the combined effect of calcium and exercise on  bone gain in children . Two milk-powder products containing either 800 mg of calcium phosphate ( calcium ) or not ( placebo ) were r and omly allocated to 113 healthy premenarchal girls on a daily basis for 1 year . The group was composed of 63 exercise ( 7.2 + /- 4 hours of exercise/week ) and 50 sedentary ( 1.2 + /- 0.8 hours of exercise/week ) children . The final experiment had 4 groups : exercise/calcium ( n = 12 ) , exercise/placebo ( n = 42 ) , sedentary/calcium ( n = 10 ) , and sedentary/placebo ( n = 21 ) . Bone mineral density ( BMD ) at 6 skeletal sites and body composition were determined by DXA . Bone age was calculated and the daily spontaneous calcium intake was assessed by a frequency question naire . All the tests were performed at baseline and 1 year by the same observer . BMD gains were significantly greater in the exercise/calcium group than in other groups at the total body ( increase of 6.3 % , p < 0.05 ) , lumbar spine ( 11 % , p < 0.05 ) , femoral neck ( 8.2 % , p < 0.02 ) , and Ward 's triangle ( 9.3 % , p < 0.01 ) . There was no difference between the other groups . These data suggest that calcium supplementation increases the effect of physical exercise on bone mineral acquisition in the period preceding puberty , and that calcium supplementation without physical activity does not improve the BMD acquisition during this period . Physical exercise that stimulates bone accretion needs a high calcium intake to be completely effective BACKGROUND Our r and omized , placebo-controlled supplementation study of 160 rural Gambian children aged 8.3 - 11.9 y showed that an increase in calcium intake of 714 mg/d for 12 mo result ed in a 5 % increase in forearm bone mineral acquisition and a 22 % decrease in plasma osteocalcin concentration , a bone formation marker , but had no effect on height or bone dimensions . OBJECTIVE We investigated whether these results were sustained after supplement withdrawal . DESIGN All participants were followed up 12 ( FU1 ) and 24 ( FU2 ) mo after supplementation ended . Bone mineral content ( BMC ) , bone mineral density ( BMD ) , and BMC adjusted for bone width , body weight , and height ( size-adjusted BMC ) were measured at the midshaft and distal radius . Plasma osteocalcin concentration was measured at FU1 . RESULTS At follow-up , the calcium group had greater bone mineral status than did the placebo group at the midshaft radius ( mean difference + /- SE ) , FU1 : BMC ( 4.7 + /- 1.6 % ; P = 0.004 ) , BMD ( 5.1 + /- 1.1 % ; P < /= 0.0001 ) , size-adjusted BMC ( 5.0 + /- 1.1 % ; P < /= 0.0001 ) ; FU2 : BMC ( 3.8 + /- 1.6 % ; P = 0.02 ) , BMD ( 2.7 + /- 1.3 % ; P = 0.04 ) , size-adjusted BMC ( 2.5 + /- 1.3 % ; P = 0.06 ) . Similar differentials were observed at the distal radius but were not significant . No significant differences in plasma osteocalcin concentrations ( FU1 : -0.5 + /- 6.5 % ; P = 0.9 ) were observed between groups . CONCLUSION Although some of the effects of calcium supplementation were still evident at follow-up , further studies are required to determine whether short-term increases in calcium intake have lasting benefits for Gambian children Background Vitamin D insufficiency in children may have long-term skeletal consequences as vitamin D affects calcium absorption , bone mineralization and bone mass attainment . Methodology /Principal Findings This school-based study investigated vitamin D status and its association with vitamin D intake and bone health in 195 Finnish children and adolescents ( age range 7–19 years ) . Clinical characteristics , physical activity and dietary vitamin D intake were evaluated . Blood and urine sample s were collected for serum 25-hydroxyvitamin D ( 25-OHD ) and other parameters of calcium homeostasis . Bone mineral density ( BMD ) and body composition were measured with dual-energy X-ray absorptiometry ( DXA ) . Altogether 71 % of the subjects were vitamin D insufficient ( 25-OHD < 50 nmol/L ) . The median 25-OHD was 41 nmol/L for girls and 45 nmol/L for boys , and the respective median vitamin D intakes 9.1 µg/day and 10 µg/day . In regression analysis , after adjusting for relevant factors , 25-OHD concentration explained 5.6 % of the variance in lumbar BMD ; 25-OHD and exercise together explained 7.6 % of the variance in total hip BMD and 17 % of the variance in whole body BMD . S-25-OHD was an independent determinant of lumbar spine and whole body BMD and in magnitude surpassed the effects of physical activity . Conclusions / Significance Vitamin D insufficiency was common even when vitamin D intake exceeded the recommended daily intake . Vitamin D status was a key determinant of BMD . The findings suggest urgent need to increase vitamin D intake to optimize bone health in children BACKGROUND Increased vitamin D intake may preserve or increase bone mineral density ( BMD ) in older persons . OBJECTIVE A 2-y double-blind study was undertaken to determine whether weekly administration of 10 000 units of vitamin D(2 ) maintained or increased BMD in younger postmenopausal women more efficiently than did calcium supplements alone . DESIGN One hundred eighty-seven women who were > or= 1 y postmenopausal were r and omly assigned to take either 1000 mg Ca/d after the evening meal or 1000 mg Ca/d plus 10 000 U vitamin D(2)/wk in a double-blind , placebo-controlled format . The BMD of the proximal forearm , lumbar spine , femoral neck , Ward 's triangle , and femoral trochanter was measured at 6-mo intervals by osteodensitometry . RESULTS During the 2-y period , there was no significant difference in the change in BMD at any site between the subjects taking calcium supplements and those taking calcium plus vitamin D(2 ) . Both groups significantly ( P < 0.005 ) gained BMD in Ward 's triangle and the femoral trochanter but significantly ( P < 0.005 ) lost bone in the proximal radius . There was no significant change in the lumbar spine or femoral neck BMD . CONCLUSION In younger postmenopausal women ( age : 56 y ) whose average baseline serum 25-hydroxyvitamin D concentration was well within the normal range , the addition of 10 000 U vitamin D(2)/wk to calcium supplementation at 1000 mg/d did not confer benefits on BMD beyond those achieved with calcium supplementation alone
Calcium supplements  increased BMD by 0.7 - 1.8 % at all five skeletal sites at one , two , and over two and a half years , but the size of the increase in BMD at later time points was similar to the increase at one year .
Increasing calcium intake from dietary sources or by taking calcium supplements produces small non-progressive increases in BMD , which are unlikely to lead to a clinical ly significant reduction in risk of fracture
OBJECTIVE To determine whether increasing calcium intake from dietary sources affects  bone mineral density ( BMD ) and , if so , whether the effects are similar to those of calcium supplements .