For hip fracture , at a 15 % relative risk , the effect estimate lay between the futility boundary and the inferior boundary , meaning there is reliable evidence that vitamin D supplementation does not reduce hip fractures by this amount , but uncertainty remains as to whether it might increase hip fractures .
The effect estimate lay within the futility boundary at thresholds of 0·5 % for total hip , forearm , and total body bone mineral density , and 1·0 % for lumbar spine and femoral neck , providing reliable evidence that vitamin D does not alter these outcomes by these amounts .
INTERPRETATION Our findings suggest that vitamin D supplementation does not prevent fractures or falls , or have clinical ly meaningful effects on bone mineral density .
There were no differences between the effects of higher and lower doses of vitamin D. There is little justification to use vitamin D supplements to maintain or improve musculoskeletal health .
BACKGROUND The effects of vitamin D on fractures , falls , and bone mineral density are uncertain , particularly for high vitamin D doses .
We aim ed to determine the effect of vitamin D supplementation on fractures , falls , and bone density .
A randomized controlled trial of vitamin D3 supplementation in African American women.
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
For hip fracture , at a 15 % relative risk , the effect estimate lay between the futility boundary and the inferior boundary , meaning there is reliable evidence that vitamin D supplementation does not reduce hip fractures by this amount , but uncertainty remains as to whether it might increase hip fractures .
The effect estimate lay within the futility boundary at thresholds of 0·5 % for total hip , forearm , and total body bone mineral density , and 1·0 % for lumbar spine and femoral neck , providing reliable evidence that vitamin D does not alter these outcomes by these amounts .
INTERPRETATION Our findings suggest that vitamin D supplementation does not prevent fractures or falls , or have clinical ly meaningful effects on bone mineral density .
There were no differences between the effects of higher and lower doses of vitamin D. There is little justification to use vitamin D supplements to maintain or improve musculoskeletal health .
BACKGROUND The effects of vitamin D on fractures , falls , and bone mineral density are uncertain , particularly for high vitamin D doses .
We aim ed to determine the effect of vitamin D supplementation on fractures , falls , and bone density .