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 .
The effect of high-dose vitamin D on bone mineral density and bone turnover markers in postmenopausal women with low bone mass—a randomized controlled 1-year trial
Summary Vitamin D is widely used in osteoporosis treatment , although the optimal dose is not known . This 1-year clinical study among 297 women aged 50–80 years old showed that a vitamin D3 dose of 6,500 IU/day was not better than the st and ard dose of 800 IU/day in improving bone mineral density ( BMD ) in the hip and spine . Introduction The purpose of this study was to determine whether a high dose of vitamin D3 was better than the st and ard dose in improving BMD and reducing bone turnover in postmenopausal women with reduced bone mass . Methods The study was a 1-year r and omized double-blind controlled trial comparing high-dose vitamin D3 with the st and ard dose .  Postmenopausal women ( n = 297 ) with a BMD T-score ≤ −2.0 in either lumbar spine ( L2–4 ) or total hip were included and r and omized to 6,500 IU vitamin D3/day ( 20,000 IU twice per week + 800 IU/day ) or 800 IU vitamin D3/day ( placebo twice per week + 800 IU/day ) . Both groups were given 1,000 mg elemental calcium/day . The primary endpoint was a change in BMD in total hip and lumbar spine ( L2–4 ) . Results After 1 year , serum 25-hydroxyvitamin D ( 25(OH)D ) increased [ mean ( SD ) ] from 71 ( 23 ) to 185 ( 34 ) nmol/l and from 71 ( 22 ) to 89 ( 17 ) nmol/l in the high- and st and ard-dose vitamin D groups , respectively . BMD at all measurement sites was unchanged or slightly improved with no significant differences between the groups . Although bone turnover was reduced in both groups , the more pronounced reduction in serum levels of the bone formation marker P1NP in the st and ard-dose group may indicate that this treatment was more efficient . Adverse events did not differ between the groups . Conclusions One year treatment with 6,500 IU vitamin D3/day was not better than 800 IU/day regarding BMD in vitamin D-replete postmenopausal women with reduced bone mass and was less efficient in reducing bone turnover
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 .