title: Effect of vitamin D supplementation on vitamin D status and bone turnover markers in young adults The necessity and safety of calcium and vitamin D in the elderly. Calcium Absorption Varies within the Reference Range for Serum 25-Hydroxyvitamin D Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Effect of Supplementation with Vitamin D3 and Calcium on Quantitative Ultrasound of Bone in Elderly Institutionalized Women: A Longitudinal Study
   Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol. Effects of calcium, dairy product, and vitamin D supplementation on bone mass accrual and body composition in 10-12-y-old girls: a 2-y randomized trial. Calcium and cholecalciferol: effects of small supplements in normal men. Vitamin D supplementation in elderly nursing home residents increases 25(OH)D but not 1,25(OH)2D. Evidence that vitamin D3 increases serum 25-hydroxyvitamin D more efficiently than does vitamin D2. Effects of ergocalciferol added to calcium on the risk of falls in elderly high-risk women. Double Blind Study on the Need for Vitamin D Supplementation in Prepubertal Children A higher dose of vitamin d reduces the risk of falls in nursing home residents: a randomized, multiple-dose study. Calcium malabsorption in the elderly: the effect of treatment with oral 25‐hydroxyvitamin D3 Two-year randomized controlled trial of vitamin K1 (phylloquinone) and vitamin D3 plus calcium on the bone health of older women. Supplementation with oral vitamin D3 and calcium during winter prevents seasonal bone loss: a randomized controlled open-label prospective trial. Effect of vitamin D supplementation on wintertime and overall bone loss in healthy postmenopausal women. A positive dose-response effect of vitamin D supplementation on site-specific bone mineral augmentation in adolescent girls: a double-blinded randomized placebo-controlled 1-year intervention. Effect of cholecalciferol plus calcium on falling in ambulatory older men and women: a 3-year randomized controlled trial. Effects of vitamin D and calcium supplementation on falls: a randomized controlled trial. Prevention of femoral and lumbar bone loss with hormone replacement therapy and vitamin D3 in early postmenopausal women: a population-based 5-year randomized trial. Effects of vitamin D supplementation on strength, physical function, and health perception in older, community-dwelling men. Bone mineral content and serum 25-hydroxyvitamin D concentration in breast-fed infants with and without supplemental vitamin D. A randomized controlled trial of vitamin D3 supplementation in African American women. Vitamin D status and sex hormone binding globulin: determinants of bone turnover and bone mineral density in elderly women. Effect of calcium and vitamin D supplementation on bone density in men and women 65 years of age or older. Vitamin D2 is as effective as vitamin D3 in maintaining circulating concentrations of 25-hydroxyvitamin D. Oral vitamin D3 and calcium for secondary prevention of low-trauma fractures in elderly people (Randomised Evaluation of Calcium Or vitamin D, RECORD): a randomised placebo-controlled trial. Plasma Vitamin D and 25OHD Responses of Young and Old Men to Supplementation with Vitamin D3 Prediction of bone mass density variation by bone remodeling markers in postmenopausal women with vitamin D insufficiency treated with calcium and vitamin D supplementation. How Much Vitamin D3 Do the Elderly Need? Estimation of the dietary requirement for vitamin D in healthy adults.
abstract: Objective : To assess the vitamin D status of healthy young people living in Northern Irel and and the effect of vitamin D supplementation on vitamin D status and bone turnover . Design : Double-blinded r and omised controlled intervention study . Setting : University of Ulster , Coleraine , Northern Irel and .Subjects : In total , 30 apparently healthy students ( 15 male and 15 female subjects ) , aged 18–27 years , were recruited from the university , with 27 completing the intervention . Interventions : Subjects were r and omly assigned , to receive either 15 μg ( 600 IU ) vitamin D3 and 1500 mg calcium/day ( vitamin D group ) , or 1500 mg calcium/day ( control group ) for 8 weeks between January and March . Vitamin D status , bone turnover markers , serum calcium and parathyroid hormone concentrations were measured at baseline and post intervention . Results : At baseline , vitamin D status was low in both the vitamin D group ( 47.9 ( s.d . 16.0 ) ) and the control group ( 55.5 ( s.d . 18.6 ) nmol/l 25(OH)D ) . Post intervention vitamin D status was significantly higher in the vitamin D-treated group ( 86.5 ( s.d . 24.5 ) ) compared to the control group ( 48.3 ( s.d . 16.8 ) nmol/l ) ( P<0.0001 ) . There was no significant effect of supplementation on bone turnover markers or PTH concentrations . Conclusions : This study suggests that young adults in Northern Irel and do not consume an adequate daily dietary intake of vitamin D to maintain plasma vitamin D concentrations in the wintertime . A daily supplement of 15 μg vitamin D3 significantly increased vitamin D status in these individuals to levels of sufficiency . Achievement of an optimum vitamin D status among young adults may have future positive health implication The necessity and safety of an oral calcium ( Ca ) and vitamin D regimen was evaluated in a population of 66 independently living and 73 institutionalized elderly women over an 11-week winter period . The members of both groups were r and omly assigned into trial and control groups . Serum Ca , creatinine , and calcidiol levels were measured before and after the trial . The regimen consisted of 1.558 g of Ca and 45 micrograms ( equal to 1,800 IU ) of vitamin D administered daily in addition to the normal diet . The controls received no treatment . A majority of the elderly subjects living independently had ensured their Ca , and a quarter of them also their vitamin D intake on their own initiative . The mean serum calcidiol concentration before the trial was 24.1 nmol/L in the institutionalized and 38.5 nmol/L in the elderly subjects living independently ( P less than .001 ) . After the trial , serum calcidiol was 10.4 nmol/L in the institutionalized control subjects and had decreased ( P less than .001 ) in both control groups , but increased ( P less than .001 ) in both treatment groups . The safety indicators , serum Ca , creatinine , and calcidiol , did not indicate any group or individual side effect Background : Calcium absorption is generally considered to be impaired under conditions of vitamin D deficiency , but the vitamin D status that fully normalizes absorption is not known for humans . Objective : To quantify calcium absorption at two levels of vitamin D repletion , using pharmacokinetic methods and commercially marketed calcium supplements . Design : Two experiments performed in the spring of the year , one year apart . In the first , in which participants were pretreated with 25-hydroxyvitamin D ( 25OHD )  , mean serum 25OHD concentration was 86.5 nmol/L ; and in the other , with no pretreatment , mean serum concentration was 50.2 nmol/L. Participants received 500 mg oral calcium loads as a part of a st and ard low calcium breakfast . A low calcium lunch was provided at mid-day . Blood was obtained fasting and at frequent intervals for 10 to 12 hours thereafter . Methods : Relative calcium absorption at the two 25OHD concentrations was estimated from the area under the curve ( AUC ) for the load-induced increment in serum total calcium . Results : AUC9 ( ± SEM ) , was 3.63 mg hr/dL ± 0.234 in participants pretreated with 25OHD  and 2.20 ± 0.240 in those not pretreated ( P < 0.001 ) . In brief , absorption was 65 % higher at serum 25OHD levels averaging 86.5 nmol/L than at levels averaging 50 nmol/L ( both values within the nominal reference range for this analyte ) . Conclusions : Despite the fact that the mean serum 25OHD level in the experiment without supplementation was within the current reference ranges , calcium absorptive performance at 50 nmol/L was significantly reduced relative to that at a mean 25OHD level of 86 nmol/L. Thus , individuals with serum 25-hydroxyvitamin D levels at the low end of the current reference ranges may not be getting the full benefit from their calcium intake . We conclude that the lower end of the current reference range is set too low BACKGROUND Numerous observational studies have found supplemental calcium and vitamin D to be associated with reduced risk of common cancers . However , interventional studies to test this effect are lacking . OBJECTIVE The purpose of this analysis was to determine the efficacy of calcium alone and calcium plus vitamin D in reducing incident cancer risk  of all types . DESIGN This was a 4-y , population -based , double-blind , r and omized placebo-controlled trial . The primary outcome was fracture incidence , and the principal secondary outcome was cancer incidence . The subjects were 1179 community-dwelling women r and omly selected from the population of healthy postmenopausal women aged > 55 y in a 9-county rural area of Nebraska centered at latitude 41.4 degrees N. Subjects were r and omly assigned to receive 1400 - 1500 mg supplemental calcium/d alone ( Ca-only ) , supplemental calcium plus 1100 IU vitamin D3/d ( Ca + D ) , or placebo . RESULTS When analyzed by intention to treat , cancer incidence was lower in the Ca + D women than in the placebo control subjects ( P < 0.03 ) . With the use of logistic regression , the unadjusted relative risks ( RR ) of incident cancer in the Ca + D and Ca-only groups were 0.402 ( P = 0.01 ) and 0.532 ( P = 0.06 ) , respectively . When analysis was confined to cancers diagnosed after the first 12 mo , RR for the Ca + D group fell to 0.232 ( CI : 0.09 , 0.60 ; P < 0.005 ) but did not change significantly for the Ca-only group . In multiple logistic regression models , both treatment and serum 25-hydroxyvitamin D concentrations were significant , independent predictors of cancer risk . CONCLUSIONS Improving calcium and vitamin D nutritional status substantially reduces  all-cancer risk in postmenopausal women . This trial was registered at clinical trials.gov as NCT00352170 Abstract : Supplementation of elderly institutionalized women with vitamin D and calcium  decreased hip fractures and increased hip bone mineral density . Quantitative ultrasound ( QUS ) measurements can be performed in nursing homes , and easily repeated for follow-up . However , the effect of the correction of vitamin D deficiency on QUS parameters is not known . Therefore , 248 institutionalized women aged 62–98 years were included in a 2-year open controlled study . They were r and omized into a treated group ( n = 124 ) , receiving 440 IU of vitamin D3 combined with 500 mg calcium ( 1250 mg calcium carbonate , Novartis ) twice daily , and a control group ( n = 124 ) . One hundred and three women ( 42 % ) , aged 84.5 ± 7.5 years , completed the study : 50 in the treated group , 53 in the  controls  . QUS of the calcaneus , which measures BUA ( broadb and ultrasound attenuation ) and SOS ( speed of sound ) , and biochemical analysis were performed before and after 1 and 2 years of treatment . Only the results of the women with a complete follow-up were taken into account . Both groups had low initial mean serum 25-hydroxyvitamin D levels ( 11.9 ± 1.2 and 11.7 ± 1.2 mg/l ; normal range 6.4–40.2 mg/l ) and normal mean serum parathyroid hormone ( PTH ) levels ( 43.1 ± 3.2 and 44.6 ± 3.5 ng/l ; normal range 10–70 ng/l , normal mean 31.8 ± 2.3 ng/l ) . The treatment led to a correction of the metabolic disturbances , with an increase in 25-hydroxyvitamin D by 123 % ( p50.01 ) and a decrease in PTH by 18 % ( p50.05 ) and of alkaline phosphatase by 15 % ( p50.01 ) . In the controls there was a worsening of the hypovitaminosis D , with a decrease of 25-hydroxyvitamin D by 51 % ( p50.01 ) and an increase in PTH by 51 % ( p50.01 ) , while the serum calcium level decreased by only 2 % ( p5 0.01 ) . After 2 years of treatment BUA increased significantly by 1.6 % in the treated group ( p50.05 ) , and decreased by 2.3 % in the controls ( p50.01 ) . Therefore , the difference in BUA between the treated subjects and the controls ( 3.9 % ) was significant after 2 years ( p50.01 ) . However , SOS decreased by the same amount in both groups ( approximately 0.5 % ) . In conclusion , BUA , but not SOS , reflected the positive effect on bone of supplementation with calcium and vitamin D3 in a population of elderly institutionalized women BACKGROUND The cholecalciferol inputs required to achieve or maintain any given serum 25-hydroxycholecalciferol concentration are not known , particularly within ranges comparable to the probable physiologic supply of the vitamin . OBJECTIVES The objectives were to establish the quantitative relation between steady state cholecalciferol input and the result ing serum 25-hydroxycholecalciferol concentration and to estimate the proportion of the daily requirement during winter that is met by cholecalciferol reserves in body tissue stores . DESIGN Cholecalciferol was administered daily in controlled oral doses labeled at 0 , 25 , 125 , and 250 micro g cholecalciferol for approximately 20 wk during the winter to 67 men living in Omaha ( 41.2 degrees N latitude ) . The time course of serum 25-hydroxycholecalciferol concentration was measured at intervals over the course of treatment . RESULTS From a mean baseline value of 70.3 nmol/L , equilibrium concentrations of serum 25-hydroxycholecalciferol changed during the winter months in direct proportion to the dose , with a slope of approximately 0.70 nmol/L for each additional 1 micro g cholecalciferol input . The calculated oral input required to sustain the serum 25-hydroxycholecalciferol concentration present before the study ( ie , in the autumn ) was 12.5 micro g ( 500 IU)/d , whereas the total amount from all sources ( supplement , food , tissue stores ) needed to sustain the starting 25-hydroxycholecalciferol concentration was estimated at approximately 96 micro g ( approximately 3800 IU)/d . By difference , the tissue stores provided approximately 78 - 82 micro g/d . CONCLUSIONS Healthy men seem to use 3000 - 5000 IU cholecalciferol/d , apparently meeting > 80 % of their winter cholecalciferol need with cutaneously synthesized accumulations from solar sources during the preceding summer months . Current recommended vitamin D inputs are inadequate to maintain serum 25-hydroxycholecalciferol concentration in the absence of substantial cutaneous production of vitamin BACKGROUND Little is known about the relative effectiveness of calcium supplementation from food or pills with or without vitamin D supplementation for bone mass accrual during the rapid growth period . OBJECTIVE The purpose was to examine the effects of both food-based and pill supplements of calcium and vitamin D on bone mass and body composition  in girls aged 10 - 12 y. DESIGN This placebo-controlled intervention trial r and omly assigned 195 healthy girls at Tanner stage I-II , aged 10 - 12 y , with dietary calcium intakes < 900 mg/d to 1 of 4 groups : calcium ( 1000 mg ) + vitamin D3 ( 200 IU ) , calcium ( 1000 mg ) , cheese ( 1000 mg calcium ) , and placebo . Primary outcomes were bone indexes of the hip , spine , and whole body by dual-energy X-ray absorptiometry and of the radius and tibia by peripheral quantitative computed tomography . RESULTS With the use of intention-to-treat or efficacy analysis , calcium supplementation with cheese result ed in a higher percentage change in cortical thickness of the tibia than did placebo , calcium , or calcium + vitamin D treatment ( P = 0.01 , 0.038 , and 0.004 , respectively ) and in higher whole-body bone mineral density than did placebo treatment ( P = 0.044 ) when compliance was > 50 % . With the use of a hierarchical linear model with r and om effects to control for growth velocity , these differences disappeared . CONCLUSIONS Increasing calcium intake by consuming cheese appears to be more beneficial for cortical bone mass accrual than the consumption of tablets containing a similar amount of calcium . Diverse patterns of growth velocity may mask the efficacy of supplementation in a short-term trial of children transiting through puberty The effect of small calcium and vitamin D supplements on mineral metabolism in normal persons is unclear . To investigate the biochemical response to these medications , we administered 1000 mg Ca and 25 micrograms cholecalciferol per day or a placebo to 92 normal men for 1 y. The Ca and cholecalciferol were tolerated well . 25-Hydroxycholecalciferol [ 25-(OH)D ] and 24,25-dihydroxycholecalciferol [ 24,25-(OH)2D ] levels rose in treated subjects ; there was no definite change in 1,25-(OH)2D concentrations . The average difference in 25-(OH)D levels between treated and untreated subjects was 30 nmol/L at 1 y. Fasting serum Ca , alkaline phosphatase , creatinine , and parathyroid hormone levels and the fasting urinary excretion of Ca , phosphorus and cAMP , were not affected . However , 24-h urinary Ca excretion was higher in the supplemented group ( 3.5 + /- 1.9 vs 4.7 + /- 1.7 mmol/d , p = 0.006 ) . Serum P concentrations were slightly higher in the supplemented group at 1 y. In normal men  small calcium and cholecalciferol supplements are safe , provide adequate vitamin D nutrition and apparently increase net gastrointestinal Ca absorption Vitamin D metabolism in elderly individuals can be compromised by several mechanisms . We previously described reduced concentrations of 1,25-dihydroxyvitamin D [ 1,25(OH)2D ] in 30 % of elderly nursing home residents . The present study assesses the effect of vitamin D supplementation on 25-hydroxyvitamin D [ 25(OH)D ] and 1,25(OH)2D . We performed a double-blind study in which 30 elderly nursing home residents were r and omly given either 50 micrograms vitamin D or a placebo daily for 6 wk . Vitamin D metabolites , immunometrically assayed parathyroid hormone ( IRMA-PTH ) , ionized calcium , and bone Gla hormone ( BGP ) were measured in serum at baseline and biweekly for 6 wk . Serum 25(OH)D concentrations increased significantly ( P less than 0.0001 ) over the 6 wk in the treatment group but were unchanged in the placebo group . Serum 1,25(OH)2D , ionized calcium , BGP , and PTH were not significantly altered by the supplement . We conclude that vitamin D supplementation results in an increase in circulating 25(OH)D but not 1,25(OH)2D ; however , the long-term effect on bone mineral metabolism remains unclear In all species tested , except humans , biological differences between vitamins D2 and D3 are accepted as fact . To test the presumption of equivalence in humans , we compared the ability of equal molar quantities of vitamin D2 or D3 to increase serum 25-hydroxyvitamin D [ 25(OH)D ] , the measure of vitamin D nutrition .  Subjects took 260 nmol ( approximately 4000 IU ) vitamin D2  ( n=17 ) or vitamin D3  ( n=55 ) daily for 14 d. 25(OH)D was assayed with a method that detects both the vitamin D2 and D3 forms . With vitamin D3 , mean ( + /-SD ) serum 25(OH)D increased from 41.3+/-17.7 nmol/L before to 64.6+/-17.2 nmol/L after treatment . With vitamin D2 , the 25(OH)D concentration went from 43.7+/-17.7 nmol/L before to 57.4+/-13.0 nmol/L after . The increase in 25(OH)D with vitamin D3  was 23.3+/-15.7 nmol/L , or 1.7 times the increase obtained with vitamin D2 ( 13.7+/-11.4 nmol/L ; P=0.03 ) . There was an inverse relation between the increase in 25(OH)D and the initial 25(OH)D concentration . The lowest 2 tertiles for basal 25(OH)D showed larger increases in 25(OH)D : 30.6 and 25.5 nmol/L , respectively , for the first and second tertiles . In the highest tertile [ 25(OH)D > 49 nmol/L ] the mean increase in 25(OH)D was 13.3 nmol/L ( P < 0.03 for comparison with each lower tertile ) . Although the 1.7-times greater efficacy for vitamin D3 shown here may seem small , it is more than what others have shown for 25(OH)D increases when comparing 2-fold differences in vitamin D3 dose . The assumption that vitamins D2 and D3 have equal nutritional value is probably wrong and should be reconsidered BACKGROUND Ergocalciferol ( vitamin D(2 ) ) supplementation plays a role in fall prevention , but the effect in patients living in the community in sunny climates remains uncertain . We evaluated the effect of ergocalciferol and calcium citrate supplementation compared with calcium alone on the risk of falls in older women at high risk of falling . METHODS A 1-year population -based , double-blind , r and omized controlled trial of 302 community-dwelling ambulant older women aged 70 to 90 years living in Perth , Australia ( latitude , 32 degrees S ) , with a serum 25-hydroxyvitamin D concentration of less than 24.0 ng/mL and a history of falling in the previous year . Participants were r and omized to receive ergocalciferol , 1000 IU/d , or identical placebo ( hereinafter , ergocalciferol and control groups , respectively ) . Both groups received calcium citrate , 1000 mg/d . Fall data were collected every 6 weeks . RESULTS Ergocalciferol therapy reduced the risk of having at least 1 fall over 1 year after adjustment for baseline height , which was significantly different between the 2 groups ( ergocalciferol group , 53.0 % ; control group , 62.9 % ; odds ratio [ OR ] , 0.61 ; 95 % confidence interval [ CI ] , 0.37 - 0.99 ) . When those who fell were grouped by the season of first fall or the number of falls they had , ergocalciferol treatment reduced the risk of having the first fall in winter and spring ( ergocalciferol group , 25.2 % ; control group , 35.8 % ; OR , 0.55 ; 95 % CI , 0.32 - 0.96 ) but not in summer and autumn , and reduced the risk of having 1 fall ( ergocalciferol group , 21.2 % ; control group , 33.8 % ; OR , 0.50 ; 95 % CI , 0.28 - 0.88 ) but not multiple falls . CONCLUSION Patients with a history of falling and vitamin D insufficiency living in sunny climates benefit from ergocalciferol supplementation in addition to calcium , which is associated with a 19 % reduction in the relative risk of falling , mostly in winter ABSTRACT . Fifty‐one healthy prepubertal schoolchildren were followed for 13 months in a double blind study . Twenty‐four of them were supplemented with 400 IU of vitamin D2 5–7 times weekly , while 27 received a placebo . The children were examined in winter both at the beginning and at the end of the study , and in the middle of the study in autumn . Mean 25‐hydroxyvitamin D levels in the supplemented group were significantly higher than those in the placebo group both in autumn and in winter , when the study ended . The vitamin D supplementation did not , however , affect other vitamin D metabolites , serum calcium , albumin , inorganic phosphorus , parathyroid hormone concentrations or alkaline phosphatase activity . Moreover , the supplementation caused no alterations in the weight or height gain or bone mineral content of the distal radius of the children , and thus sub clinical rickets could not be shown OBJECTIVES To determine the effect of four vitamin D supplement doses on falls risk in elderly nursing home residents . DESIGN Secondary data analysis of a previously conducted r and omized clinical trial . SETTING Seven hundred twenty-five-bed long-term care facility . PARTICIPANTS One hundred twenty-four nursing home residents ( average age 89 ) . INTERVENTION Participants were r and omly assigned to receive one of four vitamin D supplement doses ( 200 IU , 400 IU , 600 IU , or 800 IU ) or placebo daily for 5 months . MEASUREMENTS Number of fallers and number of falls assessed using facility incident tracking data base . RESULTS Over the 5-month study period , the proportion of participants with falls was 44 % in the placebo group ( 11/25 ) , 58 % ( 15/26 ) in the 200 IU group , 60 % ( 15/25 ) in the 400 IU group , 60 % ( 15/25 ) in the 600 IU group , and 20 % ( 5/23 ) in the 800 IU group . Participants in the 800 IU group had a 72 % lower adjusted-incidence rate ratio of falls than those taking placebo over the 5 months ( rate ratio=0.28 ; 95 % confidence interval=0.11 - 0.75 ) . No significant differences were observed for the adjusted fall rates compared to placebo in any of the other supplement groups . CONCLUSION Nursing home residents in the highest vitamin D group ( 800 IU ) had a lower number of fallers and a lower incidence rate of falls over 5 months than those taking lower doses . Adequate vitamin D supplementation in elderly nursing home residents could reduce the number of falls experienced by this high falls risk group Abstract . Calcium malabsorption is common in the elderly and may contribute to the development of age‐related bone loss . To investigate its cause , we have measured  radio‐calcium absorption , plasma 25‐hydroxyvitamin D , 1,25‐dihydroxyvitamin D and parathyroid hormone  in forty‐eight elderly women with a normal plasma creatinine . Calcium malabsorption was associated with low 25‐hydroxyvitamin D concentrations and was corrected by increasing these into the normal range by treatment with oral 25‐hydroxyvitamin D3 . Treatment also increased 1,25‐dihydroxyvitamin D , and decreased parathyroid hormone concentrations UNLABELLED Dietary supplementation with vitamin K(1 ) , with vitamin D(3 ) and calcium or their combination , was examined in healthy older women during a 2-year , double-blind , placebo-controlled trial . Combined vitamin K with vitamin D plus calcium was associated with a modest but significant increase in BMC at the ultradistal radius but not at other sites in the hip or radius . INTRODUCTION The putative beneficial role of high dietary vitamin K(1 ) ( phylloquinone ) on BMD and the possibility of interactive benefits with vitamin D were studied in a 2-year double-blind , placebo-controlled trial in healthy Scottish women > or = 60 years of age . MATERIAL S AND METHODS Healthy , nonosteoporotic women ( n = 244 ) were r and omized to receive either ( 1 ) placebo , ( 2 ) 200 microg/day vitamin K(1 ) , ( 3 ) 10 microg ( 400 IU ) vitamin D(3 ) plus 1000 mg calcium/day , or ( 4 ) combined vitamins K(1 ) and D(3 ) plus calcium . Baseline and 6-month measurements included DXA bone mineral scans of the hip and wrist , markers of bone turnover , and vitamin status . Supplementation effects were tested using multivariate general linear modeling , with full adjustment for baseline and potential confounding variables . RESULTS Significant bone mineral loss was seen only at the mid-distal radius but with no significant difference between groups . However , women who took combined vitamin K and vitamin D plus calcium showed a significant and sustained increase in both BMD and BMC at the site of the ultradistal radius . Serum status indicators responded significantly to respective supplementation with vitamins K and D. Over 2 years , serum vitamin K(1 ) increased by 157 % ( p < 0.001 ) , the percentage of undercarboxylated osteocalcin ( % GluOC ) decreased by 51 % ( p < 0.001 ) , serum 25-hydroxyvitamin D [ 25(OH)D ] increased by 17 % ( p < 0.001 ) , and PTH decreased by 11 % ( p = 0.049 ) . CONCLUSIONS These results provide evidence of a modest synergy in healthy older women from nutritionally relevant intakes of vitamin K(1 ) together with supplements of calcium plus moderate vitamin D(3 ) to enhance BMC at the ultradistal radius , a site consisting of principally trabecular bone . The substantial increase in gamma-carboxylation of osteocalcin by vitamin K may have long-term benefits and is potentially achievable by increased dietary intakes of vitamin K rather than by supplementation UNLABELLED Bone metabolism follows a seasonal pattern with high bone turnover and bone loss during the winter . In a r and omized , open-label 2-year sequential follow-up study of 55 healthy adults , we found that supplementation with oral vitamin D3 and calcium during winter abolished seasonal changes in calciotropic hormones and markers of bone turnover and led to an increase in BMD . Supplementation with oral vitamin D3 and calcium during the winter months seems to counteract the effects of seasonal changes in vitamin D and thus may be beneficial as a primary prevention strategy for age-related bone loss . INTRODUCTION Bone metabolism follows a seasonal pattern characterized by high bone turnover and bone loss during winter . We investigated whether wintertime supplementation with oral vitamin D3 and calcium had beneficial effects on the circannual changes in bone turnover and bone mass . MATERIAL S AND METHODS This prospect i ve study comprised an initial observation period of 12 months ( " year 1 " ) , followed by an intervention during parts of year 2 . Fifty-five healthy subjects living in southwestern Germany ( latitude , 49.5 degrees N ) were r and omized into two groups : 30 subjects were assigned to the treatment group and received oral cholecalciferol ( 500 IU/day ) and calcium ( 500 mg/day ) during the winter months of year 2 ( October-April ) , while 25 subjects assigned to the control group obtained no supplements . Primary endpoints were changes in calciotropic hormones [ serum 25(OH)D , 1,25(OH)2D , and parathyroid hormone ] , markers of bone formation ( serum bone-specific alkaline phosphatase ) and of bone resorption ( urinary pyridinoline and deoxypyridinoline ) , and changes in lumbar spine and femoral neck BMD . RESULTS Forty-three subjects completed the study . During year 1 , calciotropic hormones , markers of bone turnover , and BMD varied by season in both groups . During the winter months of year 1 , bone turnover was significantly accelerated , and lumbar spine and femoral BMD declined by 0.3 - 0.9 % . In year 2 , seasonal changes in calciotropic hormones and markers of bone turnover were either reversed or abolished in the intervention group while unchanged in the control cohort . In the subjects receiving oral vitamin D3 and calcium , lumbar and femoral BMD increased significantly ( lumbar spine : + 0.8 % , p = 0.04 versus year 1 ; femoral neck : + 0.1 % , p = 0.05 versus year 1 ) , whereas controls continued to lose bone ( intervention group versus control group : lumbar spine , p = 0.03 ; femoral neck , p = 0.05 ) . CONCLUSIONS Supplementation with oral vitamin D3 and calcium during winter prevents seasonal changes in bone turnover and bone loss in healthy adults . It seems conceivable that annually recurring cycles of low vitamin D and mild secondary hyperparathyroidism during the winter months contributes , at least in part and over many years , to age-related bone loss . Supplementation with low-dose oral vitamin D3 and calcium during winter may be an efficient and inexpensive strategy for the primary prevention of bone loss in northern latitudes OBJECTIVES To determine whether relative vitamin D deficiency during the winter months contributes to age-related bone loss  and whether rates of change in hard- and soft-tissue mass vary during the year . DESIGN Double-blind , placebo-controlled , 1-year trial in 249 women in which equal numbers of women were r and omized to either placebo or 400 IU of vitamin D daily . All women received 377 mg/d of supplemental calcium largely as calcium citrate malate . PATIENTS Healthy , ambulatory postmenopausal women with usual intakes of vitamin D of 100 IU/d . MEASUREMENTS Duplicate spine and whole-body scans were done by dual energy x-ray absorptiometry at 6-month intervals that were timed to periods when 25-hydroxyvitamin D levels were highest and lowest . Period 1 was June-July to December-January and period 2 was December-January to the next June-July . Serum parathyroid hormone and plasma 25-hydroxyvitamin D levels were measured during periods 1 and 2 . MAIN RESULTS In the placebo group , spinal bone mineral density increased in period 1 , decreased in period 2 , and sustained no net change . Women treated with vitamin D had a similar spinal increase in period 1 ( 1.46 % compared with 1.40 % in placebo ) , less loss in period 2 ( -0.54 % compared with -1.22 % , CI for the difference , 0.05 % to 1.31 % , P = 0.032 ) and a significant overall benefit ( 0.85 % compared with 0.15 % , CI for the difference , 0.03 % to 1.37 % , P = 0.04 ) . In period 2 , 25-hydroxyvitamin D levels were lower and parathyroid hormone levels were higher in the placebo than in the vitamin D group . Whole-body lean and fat tissue and bone mineral density varied during the year but did not change overall . CONCLUSIONS At latitude 42 degrees , healthy postmenopausal women with vitamin D intakes of 100 IU daily can significantly reduce late wintertime bone loss and improve net bone density of the spine over one year by increasing their intake of vitamin D to 500 IU daily . A long-term benefit of preventing vitamin D insufficiency in the winter seems likely although it remains to be shown . Observed changes in bone as well as in fat and lean tissue appear to be related to season UNLABELLED The effect of vitamin D supplementation on bone mineral augmentation in 212 adolescent girls with adequate calcium intake was studied in a r and omized placebo-controlled setting . Bone mineral augmentation determined by DXA increased with supplementation both in the femur and the lumbar vertebrae in a dose-responsive manner . Supplementation decreased the urinary excretion of resorption markers , but had no impact on formation markers . INTRODUCTION Adequate vitamin D intake protects the elderly against osteoporosis , but there exists no indisputable evidence that vitamin D supplementation would benefit bone mineral augmentation . The aim of this 1-year study was to determine in a r and omized double-blinded trial the effect of 5 and 10 microg vitamin D3 supplementation on bone mineral augmentation in adolescent girls with adequate dietary calcium intake . MATERIAL S AND METHODS Altogether , 228 girls ( mean age , 11.4 + /- 0.4 years ) participated . Their BMC was measured by DXA from the femur and lumbar spine . Serum 25-hydroxyvitamin D [ S-25(OH)D ] , intact PTH ( S-iPTH ) , osteocalcin ( S-OC ) , and urinary pyridinoline ( U-Pyr ) and deoxypyridinoline ( U-Dpyr ) were measured . Statistical analysis was performed both with the intention-to-treat ( IT ) and compliance-based ( CB ) method . RESULTS In the CB analysis , vitamin D supplementation increased femoral BMC augmentation by 14.3 % with 5 microg and by 17.2 % with 10 microg compared with the placebo group ( ANCOVA , p = 0.012 ) . A dose-response effect was observed in the vertebrae ( ANCOVA , p = 0.039 ) , although only with the highest dose . The mean concentration of S-25(OH)D increased ( p < 0.001 ) in the 5-microg group by 5.7 + /- 15.7 nM and in the 10-microg group by 12.4 + /- 13.7 nM , whereas it decreased by 6.7 + /- 11.3 nM in the placebo group . Supplementation had no effect on S-iPTH or S-OC , but it decreased U-DPyr ( p = 0.042 ) . CONCLUSIONS Bone mineral augmentation in the femur was 14.3 % and 17.2 % higher in the groups receiving 5 and 10 microg of vitamin D , respectively , compared with the placebo group , but only 10 mug increased lumbar spine BMC augmentation significantly . Vitamin D supplementation decreased the concentration of bone resorption markers , but had no impact on bone formation markers , thus explaining increased bone mineral augmentation . However , the positive effects were noted with the CB method but not with IT BACKGROUND A recent meta- analysis found that cholecalciferol ( vitamin D ) should reduce falls by more than 20 % . However , little is known about whether supplemental cholecalciferol plus calcium citrate malate will lower the long-term risk of falling in men , active older individuals , and older individuals with higher 25-hydroxyvitamin D levels . METHODS We studied the effect of 3-year supplementation with cholecalciferol-calcium on the risk of falling  at least once in 199 men and 246 women 65 years or older and living at home . Individuals received 700 IU of cholecalciferol plus 500 mg of calcium citrate malate per day or placebo in a r and omized double-blind manner . Subjects were classified as less physically active if physical activity was below the median level . Low 25-hydroxyvitamin D levels were classified as those below 32 ng/mL ( < 80 nmol/L ) . RESULTS In 3 years , 55 % of women and 45 % of men reported at least 1 fall . Mean + /- SD baseline 25-hydroxyvitamin D levels were 26.6 + /- 12.7 ng/mL ( 66.4 + /- 31.7 nmol/L ) in women and 33.2 + /- 14.2 ng/mL ( 82.9 + /- 34.9 ) in men . Cholecalciferol-calcium significantly reduced the odds of falling in women ( odds ratio [ OR ] , 0.54 ; 95 % confidence interval [ CI ] , 0.30 - 0.97 ) , but not in men ( OR , 0.93 ; 95 % CI , 0.50 - 1.72 ) . Fall reduction was most pronounced in less active women ( OR , 0.35 ; 95 % CI , 0.15 - 0.81 ) . Baseline 25-hydroxyvitamin D level did not modulate the treatment effect . CONCLUSIONS Long-term dietary cholecalciferol-calcium supplementation reduces the odds of falling in ambulatory older women by 46 % , and especially in less active women by 65 % . Supplementation had a neutral effect in men independent of their physical activity level Specific receptors for vitamin D have been identified in human muscle tissue . Cross-sectional studies show that elderly persons with higher vitamin D serum levels have increased muscle strength and a lower number of falls . We hypothesized that vitamin D and calcium supplementation would improve musculoskeletal function and decrease falls . In a double-blind r and omized controlled trial , we studied 122 elderly women ( mean age , 85.3 years ; range , 63 - 99 years ) in long-stay geriatric care . Participants received 1200 mg calcium plus 800 IU cholecalciferol ( Cal+D-group ; n = 62 ) or 1200 mg calcium ( Cal-group ; n = 60 ) per day over a 12-week treatment period . The number of falls per person ( 0 , 1 , 2 - 5 , 6 - 7 , > 7 falls ) was compared between the treatment groups . In an intention to treat analysis , a Poisson regression model was used to compare falls after controlling for age , number of falls in a 6-week pretreatment period , and baseline 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum concentrations . Among fallers in the treatment period , crude excessive fall rate ( treatment - pretreatment falls ) was compared between treatment groups . Change in musculoskeletal function ( summed score of knee flexor and extensor strength , grip strength , and the timed up&go test ) was measured as a secondary outcome . Among subjects in the Cal+D-group , there were significant increases in median serum 25-hydroxyvitamin D ( + 71 % ) and 1,25-dihydroxyvitamin D ( + 8 % ) . Before treatment , mean observed number of falls per person per week was 0.059 in the Cal+D-group and 0.056 in the Cal-group . In the 12-week treatment period , mean number of falls per person per week was 0.034 in the Cal+D-group and 0.076 in the Cal-group . After adjustment , Cal+D-treatment accounted for a 49 % reduction of falls ( 95 % CI , 14 - 71 % ; p < 0.01 ) based on the fall categories stated above . Among fallers of the treatment period , the crude average number of excessive falls was significantly higher in the Cal-group ( p = 0.045 ) . Musculoskeletal function improved significantly in the Cal+D-group ( p = 0.0094 ) . A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49 % compared with calcium alone . Over this short-term intervention , recurrent fallers seem to benefit most by the treatment . The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function The long term effects of hormone replacement therapy ( HRT ) and vitamin D3 ( Vit D ) on bone mineral density ( BMD ) were studied . A total of 464 nonosteoporotic early postmenopausal women from the Kuopio Osteoporosis Study ( n = 13100 ) were r and omized to four groups : 1 ) HRT ( sequential combination of 2 mg estradiol valerate and 1 mg cyproterone acetate , 2 ) Vit D3 ( 300 and 100 IU/day during the fifth year ) , 3 ) HRT and Vit D combined , and 4 ) placebo .  Lumbar ( L2-L4 ) and femoral neck BMD were determined by dual x-ray absorptiometry ( DXA ) at baseline and after 2.5 and 5 yr of treatment . Intention to treat analysis ( n = 464 ) showed that after 5 yr , lumbar BMD remained unchanged in the HRT and HRT plus Vit D groups [ + 0.2 % ( P = 0.658 ) and + 0.9 % ( P = 0.117 ) , respectively ] , whereas lumbar BMD decreased by 4.6 % in the Vit D group and by 4.5 % in the placebo group ( P < 0.001 in both ) . The loss of femoral neck BMD was less in the HRT ( -1.4 % ; P = 0.005 ) and HRT plus Vit D ( -1.3 % ; P = 0.003 ) groups than in the Vit D and placebo groups ( -4.3 % ; P < 0.001 in both ) . Among those 370 women who complied with the 5-yr treatment , the effect was more pronounced : lumbar BMD had increased by 1.5 % in the HRT ( P = 0.009 ) and by 1.8 % in the HRT plus Vit D group ( P = 0.005 ) , with a plateau after 2.5 yr , whereas lumbar BMD had decreased in both the Vit D and placebo groups ( 4.6 % and 4.7 % ; P < 0.001 , respectively ) . Femoral neck BMD decreased again less in the HRT ( -0.4 % ) and HRT plus Vit D ( -0.6 % ) groups than in the Vit D and placebo groups ( -4.4 % in both ) . This study confirms the positive long term effect of HRT on BMD also seen in intention to treat analysis . The data suggest that low dose vitamin D3 supplementation does not prevent  bone loss in healthy , nonosteoporotic , early postmenopausal women , and it confers no benefit additional to that of HRT alone OBJECTIVES To study the effects of vitamin D supplementation in healthier population s of men . DESIGN : R and omized , controlled trial . SETTING General clinical research center . PARTICIPANTS Sixty-five healthy , community-dwelling men ( mean age+/-st and ard deviation=76+/-4 , range 65 - 87 ) . INTERVENTION Cholecalciferol ( 1,000 IU/d ) or placebo supplementation for 6 months ; all received 500 mg supplemental calcium . MEASUREMENTS Upper and lower extremity muscle strength and power , physical performance and activity , health perception , calcium and vitamin D intake , and biochemical assessment , including 25-hydroxyvitamin D ( 25OHD ) , parathyroid hormone ( PTH ) , and ionized calcium levels . RESULTS The levels of 25OHD increased and PTH decreased in the cholecalciferol group , whereas there were no significant changes in the control group ( P<.001 ) . Baseline 25OHD levels correlated with baseline single-leg stance time and physical activity score . Baseline PTH levels correlated with baseline 8-foot walk time and physical activity score . No significant difference in strength , power , physical performance , or health perception was found between groups . CONCLUSION The 25OHD or PTH levels correlated with physical activity and physical performance in older , community-dwelling men with normal 25OHD status . Vitamin D supplementation increased 25OHD levels and decreased PTH levels but did not increase muscle strength or improve physical performance or health perception in this group of healthy , older men . Further investigations of the effects of vitamin D supplementation should focus on individuals with low levels of vitamin Eighteen term , healthy , appropriate for gestational age , breast-fed infants were studied in a double-blind prospect i ve study to determine whether or not supplemental vitamin D affected bone mineralization .  All patients were from a single , private pediatric practice . Nine infants were r and omly assigned to a vitamin D supplement of 400 IU/day and nine infants to a placebo . By 12 weeks of age , infants receiving placebo had a significant decrease in bone mineralization and in serum 25-hydroxyvitamin D concentrations compared to the vitamin D-supplemented group . It is not known whether or not the increased BMC at 12 weeks of age in vitamin D-supplemented breast-fed infants is of ultimate value . Supplemental vitamin D may be necessary for optimal bone mineralization in term breast-fed infants . A longer follow-up study and additional analyses are required to make conclusive statements BACKGROUND We conducted a r and omized , placebo-controlled , double-blind trial to test the hypothesis that vitamin D(3 ) supplementation would prevent bone loss in calcium-replete , African American postmenopausal women . METHODS Two hundred eight healthy black postmenopausal women , 50 to 75 years of age , were assigned to receive either placebo or 20 microg/d ( 800 IU ) of vitamin D(3 ) . Calcium supplements were provided to ensure a total calcium intake of 1200 to 1500 mg/d . After 2 years , the vitamin D(3 ) dose was increased to 50 microg/d ( 2000 IU ) in the active group , and the study continued for an additional year . Bone mineral density ( BMD ) was measured every 6 months . Markers of bone turnover , vitamin D metabolites , and parathyroid hormone ( PTH ) levels were measured in serum . RESULTS There were no significant differences in BMD between the active and control groups throughout the study . There was also no relationship between serum 25-hydroxyvitamin D levels attained and rates of bone loss . There was an increase in BMD of the total body , hip , and radius at 1 year in both groups . Over the 3 years , BMD declined at these sites by 0.26 % to 0.55 % per year . The BMD of the lumbar spine increased slightly in the placebo and active groups . There were no persistent changes in serum PTH levels or the markers of bone turnover , although there was a transient decline in PTH in both groups at 3 months . No significant adverse events were attributed to vitamin D supplementation . CONCLUSIONS There was no observed effect of vitamin D(3 ) supplementation on bone loss or bone turnover markers in calcium-replete , postmenopausal African American women . Further studies are needed to determine if these findings are applicable to women of other ethnic groups To examine the relation of the vitamin D status and the remaining estrogen activity with bone turnover and bone mineral density ( BMD ) in elderly women , BMD was measured at both hips using dual-energy X-ray absorptiometry and at the distal radius using single photon absorptiometry , in 330 healthy women aged 70 and over .  Vitamin D metabolites , sex hormone binding globulin ( SHBG ) , PTH(1 - 84 ) , osteocalcin , alkaline phosphatase , and hydroxyproline and calcium excretion in 2 h fasting urine were measured . Multiple linear regression was used to adjust for potential confounders . In 65 % of the women , serum 25(OH)D was below 30 nmol/l . Only values below a threshold for 25(OH)D were negatively related to serum PTH(1 - 84 ) ( p = 0.02 , threshold at 25 nmol/l ) and to osteocalcin levels ( p = 0.04 , threshold at 30 nmol/l ) . BMD of the femoral neck and trochanter was positively related to serum 25(OH)D ( left neck p = 0.001 ) with thresholds at 30 nmol/l whereas the distal radius was not ( p = 0.32 ) . Serum PTH was negatively related to BMD at all measurement sites ( all p < 0.001 ) . Serum SHBG , an inverse measure of estrogen activity , was positively related to osteocalcin levels ( p = 0.004 ) and the urinary hydroxyproline/creatinine ratio ( p = 0.002 ) and negatively related to the BMD of the trochanter ( left trochanter p = 0.02 ) and the distal radius ( p = 0.001 ) . We conclude that in elderly women , serum 25(OH)D levels below 30 nmol/l are associated with secondary hyperparathyroidism and increased bone turnover . SHBG is positively related to bone turnover . ( ABSTRACT TRUNCATED AT 250 WORDS BACKGROUND Inadequate dietary intake of calcium and vitamin D may contribute to the high prevalence of osteoporosis among older persons . METHODS We studied the effects of three years of dietary supplementation with calcium and vitamin D on bone mineral density , biochemical measures of bone metabolism , and the incidence of nonvertebral fractures in 176 men and 213 women 65 years of age or older who were living at home . They received either 500 mg of calcium plus 700 IU of vitamin D3 ( cholecalciferol ) per day or placebo .  Bone mineral density was measured by dual-energy x-ray absorptiometry , blood and urine were analyzed every six months , and cases of nonvertebral fracture were ascertained by means of interviews and verified with use of hospital records . RESULTS The mean ( + /-SD ) changes in bone mineral density in the calcium-vitamin D and placebo groups were as follows : femoral neck , + 0.50+/-4.80 and -0.70+/-5.03 percent , respectively ( P=0.02 ) ; spine,+2.12+/-4.06 and + 1.22+/-4.25 percent ( P=0.04 ) ; and total body , + 0.06+/-1.83 and -1.09+/-1.71 percent ( P<0.001 ) . The difference between the calcium-vitamin D and placebo groups was significant at all skeletal sites after one year , but it was significant only for total-body bone mineral density in the second and third years . Of 37 subjects who had nonvertebral fractures , 26 were in the placebo group and 11 were in the calcium-vitamin D group ( P=0.02 ) . CONCLUSIONS In men and women 65 years of age or older who are living in the community , dietary supplementation with calcium and vitamin D moderately reduced bone loss measured in the femoral neck , spine , and total body over the three-year study period and reduced the incidence of nonvertebral fractures CONTEXT Two reports suggested that vitamin D2 is less effective than vitamin D3 in maintaining vitamin D status . OBJECTIVE Our objective was to determine whether vitamin D2 was less effective than vitamin D3 in maintaining serum 25-hydroxyvitamin D levels or increased the catabolism of 25-hydroxyvitamin D3 . SUBJECTS AND DESIGN This was a r and omized , placebo-controlled , double-blinded study of healthy adults ages 18 - 84 yr who received placebo , 1000 IU vitamin D3 , 1000 IU vitamin D2 , or 500 IU vitamin D2 plus 500 IU vitamin D3 daily for 11 wk at the end of the winter . RESULTS Sixty percent of the healthy adults were vitamin D deficient at the start of the study . The circulating levels of 25-hydroxyvitamin D ( mean+/-sd ) increased to the same extent in the groups that received 1000 IU daily as vitamin D2 ( baseline 16.9+/-10.5 ng/ml ; 11 wk 26.8+/-9.6 ng/ml ) , vitamin D3 ( baseline 19.6+/-11.1 ng/ml ; 11 wk 28.9+/-11.0 ng/ml ) , or a combination of 500 IU vitamin D2 and 500 IU vitamin D3 ( baseline 20.2+/-10.4 ng/ml ; 11 wk 28.4+/-7.7 ng/ml ) . The 25-hydroxyvitamin D3 levels did not change in the group that received 1000 IU vitamin D2 daily . The 1000 IU dose of vitamin D2 or vitamin D3 did not raise 25-hydroxyvitamin D levels in vitamin D-deficient subjects above 30 ng/ml . CONCLUSION A 1000 IU dose of vitamin D2 daily was as effective as 1000 IU vitamin D3 in maintaining serum 25-hydroxyvitamin D levels and did not negatively influence serum 25-hydroxyvitamin D3 levels . Therefore , vitamin D2 is equally as effective as vitamin D3 in maintaining 25-hydroxyvitamin D status BACKGROUND Elderly people who have a fracture are at high risk of another . Vitamin D and calcium supplements are often recommended for fracture prevention . We aim ed to assess whether vitamin D3 and calcium , either alone or in combination , were effective in prevention of secondary fractures . METHODS In a factorial- design trial , 5292 people aged 70 years or older ( 4481 [ 85 % ] of whom were women ) who were mobile before developing a low-trauma fracture were r and omly assigned 800 IU daily oral vitamin D3 , 1000 mg calcium , oral vitamin D3 ( 800 IU per day ) combined with calcium ( 1000 mg per day ) , or placebo .  Participants who were recruited in 21 UK hospitals were followed up for between 24 months and 62 months . Analysis was by intention-to-treat and the primary outcome was new low-energy fractures . FINDINGS 698 ( 13 % ) of 5292 participants had a new low-trauma fracture , 183 ( 26 % ) of which were of the hip . The incidence of new , low-trauma fractures did not differ significantly between participants allocated calcium and those who were not ( 331 [ 12.6 % ] of 2617 vs 367 [ 13.7 % ] of 2675 ; hazard ratio ( HR ) 0.94 [ 95 % CI 0.81 - 1.09 ] ) ; between participants allocated vitamin D3 and those who were not ( 353 [ 13.3 % ] of 2649 vs 345 [ 13.1 % ] of 2643 ; 1.02 [ 0.88 - 1.19 ] ) ; or between those allocated combination treatment and those assigned placebo ( 165 [ 12.6 % ] of 1306 vs 179 [ 13.4 % ] of 1332 ; HR for interaction term 1.01 [ 0.75 - 1.36 ] ) . The groups did not differ in the incidence of all-new fractures , fractures confirmed by radiography , hip fractures , death , number of falls , or quality of life . By 24 months , 2886 ( 54.5 % ) of 5292 were still taking tablets , 451 ( 8.5 % ) had died , 58 ( 1.1 % ) had withdrawn , and 1897 ( 35.8 % ) had stopped taking tablets but were still providing data for at least the main outcomes . Compliance with tablets containing calcium was significantly lower ( difference : 9.4 % [ 95 % CI 6.6 - 12.2 ] ) , partly because of gastrointestinal symptoms . However , potentially serious adverse events were rare and did not differ between groups . INTERPRETATION The findings do not support routine oral supplementation with calcium and vitamin D3 , either alone or in combination , for the prevention of further fractures in previously mobile elderly people Objectives : This study was conducted to determine whether there are age differences in the plasma parent vitamin D and 25-hydroxyvitamin D ( 25OHD ) responses to eight weeks of supplementation with 20 μg/day of vitamin D3 . Methods : Twenty-five healthy young men ( age 18–35 ) and 25 healthy older men ( 62–79 ) were r and omly assigned to supplementation with 20 μg/day of vitamin D3 or to no intervention and followed for eight weeks . Plasma vitamin D3 was measured by high performance liquid chromatography and 25OHD was measured by competitive protein binding . Results : Both young and old men in the supplemented group had pronounced , rapid and similar increases in plasma vitamin D3 , whereas vitamin D3 concentrations were stable in the control group . By the end of the eight-week adaptation period , plasma vitamin D3 of young and old men had increased by 4.3 and 6.2 nmol/L respectively . In the supplemented group , mean 25OHD concentrations of both the young and old men increased during the study , and the magnitude of the change after eight weeks was nearly identical in the two age groups ( 22.5 and 22.1 nmol/L in the young and the old men , respectively ) . In the control group there was a modest decrease in 25OHD of both the young and old men . Conclusions : There appears to be no age-related impairment among men in the absorption or metabolism of 20 μg/day of vitamin D3 taken orally for at least eight weeks The aim of this study was to determine whether early changes in bone markers could predict long-term response in bone mineral density ( BMD ) after calcium ( 500 mg ) and vitamin D ( 400 IU ) supplementation twice daily in ambulatory elderly women with vitamin D insufficiency ( 25-hydroxyvitamin D , < 12 ng/ml ) . One hundred and ninety-two women ( mean age , 75 + /- 7 yr ) were r and omized to receive either the supplementation ( n = 95 ) or a placebo ( n = 97 ) in a double-blind , controlled clinical trial for 1 yr . In comparison with the placebo group , supplementation significantly increased BMD , normalized 25-hydroxyvitamin D and significantly decreased intact PTH and bone remodeling markers . The initial values of telopeptide cross-links were correlated with improvement in total body BMD [ urinary N-telopeptides ( NTX ) , r = 0.38 ; C-telopeptides ( CTX ) , r = 0.32 ; serum CTX , r = 0.28 ] , and the 3-month changes in the same markers were correlated with improvement in total body ( urinary N-telopeptides , r = -0.29 ; serum CTX , r = -0.26 ) and vertebral BMD ( CTX , r = -0.26 ; all P < 0.05 ) . We concluded that short-term changes in bone resorption markers can predict long-term variations in BMD in elderly women with vitamin D insufficiency receiving calcium  and vitamin D supplementation Background : Vitamin D insufficiency poses a problem in many parts of the world , the elderly being an especially vulnerable group . This insufficiency results from an inadequate amount of sunshine and a low dietary intake of vitamin D. Typically , insufficiency is accompanied with high intact parathyroid hormone , ( S-iPTH ) concentrations . Aims of the Study : We studied how serum 25-hydroxy vitamin D ( S-25-OHD ) concentrations respond to different doses of vitamin D3 supplementation . Secondly to determine the smallest efficient dose to maintain serum 25-OHD concentration above the insufficiency level . We also studied which dose would be efficient in decreasing S-iPTH concentration in these subjects . Subjects and Methods : Forty-nine 65- to 85-year-old women participated . The women were r and omly assigned into one of four groups receiving 0 ( placebo ) , 5 , 10 or 20 μg of vitamin D3 daily for 12 weeks . Fasting morning blood was drawn at the beginning of the study , and thereafter every second week . Calciotropic variables were assessed from serum and urine sample s. Results : The S-25-OHD concentration increased significantly ( p < 0.001 ) in all supplemented groups [ 5 μg : by 10.9 ( 8.5 ) nmol/L , 10 μg : by 14.4 ( 6.9 ) nmol/L , 20 μg : by 23.7 ( 11.9 ) nmol/L ] , whereas it decreased in the placebo group by 8.3 ( 13.2 ) nmol/L. Equilibrium in S-25-OHD concentration was reached in all groups after 6 weeks of supplementation at 57.7 ( 8.9 ) nmol/L , 59.9 ( 8.9 ) nmol/L and 70.9 ( 8.9 ) nmol/L in the groups with increasing vitamin D supplementation . The dose-response to supplementation decreased with increasing vitamin D status at baseline , r = −0.513 , p = 0.002 . S-iPTH tended to decrease in those with highest dose response to supplementation . Conclusions : A clear dose response was noted in S-25-OHD to different doses of vitamin D3 . The recommended dietary intake of 15 μg is adequate to maintain the S-25-OHD concentration around 40–55 nmol/L during winter , but if the optimal S-25-OHD is higher than that even higher vitamin D intakes are needed . Interestingly , subjects with lower vitamin D status at baseline responded more efficiently to supplementation than those with more adequate status BACKGROUND Knowledge gaps have contributed to considerable variation among international dietary recommendations for vitamin D. OBJECTIVE We aim ed to establish the distribution of dietary vitamin D required to maintain serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations above several proposed cutoffs ( ie , 25 , 37.5 , 50 , and 80 nmol/L ) during wintertime after adjustment for the effect of summer sunshine exposure and diet . DESIGN A r and omized , placebo-controlled , double-blind 22-wk intervention study was conducted in men and women aged 20 - 40 y ( n = 238 ) by using different supplemental doses ( 0 , 5 , 10 , and 15 microg/d ) of vitamin D(3 ) throughout the winter .  Serum 25(OH)D concentrations were measured by using enzyme-linked immunoassay at baseline ( October 2006 ) and endpoint ( March 2007 ) . RESULTS There were clear dose-related increments ( P < 0.0001 ) in serum 25(OH)D with increasing supplemental vitamin D(3 ) . The slope of the relation between  vitamin D intake and serum 25(OH)D was 1.96 nmol x L(-1 ) x microg(-1 ) intake . The vitamin D intake that maintained serum 25(OH)D concentrations of > 25 nmol/L in 97.5 % of the sample was 8.7 microg/d . This intake ranged from 7.2 microg/d in those who enjoyed sunshine exposure , 8.8 microg/d in those who sometimes had sun exposure , and 12.3 microg/d in those who avoided sunshine . Vitamin D intakes required to maintain serum 25(OH)D concentrations of > 37.5 , > 50 , and > 80 nmol/L in 97.5 % of the sample were 19.9 , 28.0 , and 41.1 microg/d , respectively . CONCLUSION The range of vitamin D intakes required to ensure maintenance of wintertime vitamin D status [ as defined by incremental cutoffs of serum 25(OH)D ] in the vast majority ( > 97.5 % ) of 20 - 40-y-old adults , considering a variety of sun exposure preferences , is between 7.2 and 41.1 microg/d
target: There was a suggestion that whole-body or lumbar spine BMD may be a useful biomarker in older people but not in adolescents .
  This systematic review confirmed that circulating 25(OH)D is a robust and reliable marker of vitamin D status .
background: BACKGROUND Although serum 25-hydroxyvitamin D [ 25(OH)D ] is the currently accepted vitamin D status marker of choice , use of other biomarkers or functional endpoints have been suggested .
  OBJECTIVE The objective was to systematic ally review the effectiveness of 25(OH)D , parathyroid hormone ( PTH ) , bone turnover markers , bone mineral density ( BMD ) , and calcium absorption as biomarkers of vitamin D status .