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 .
Can vitamin D supplementation reduce the risk of fracture in the elderly? A randomized controlled trial.
R and omized controlled trials have shown that a combination of vitamin D and calcium can prevent  fragility fractures in the elderly . Whether this effect is attributed to the combination of vitamin D and calcium or to one of these nutrients alone is not known . We studied if an intervention with 10 microg of vitamin D3 per day could prevent hip fracture and other osteoporotic fractures in a double-blinded r and omized controlled trial . Residents from 51 nursing homes were allocated r and omly to receive 5 ml of ordinary cod liver oil ( n = 569 ) or 5 ml of cod liver oil where vitamin D was removed ( n = 575 ) . During the study period of 2 years , fractures and deaths were registered , and the principal analysis was performed on the intention-to-treat basis . Biochemical markers were measured at baseline and after 1 year in a sub sample . Forty-seven persons in the control group and 50 persons in the vitamin D group suffered a  hip fracture . The corresponding figures for all nonvertebral fractures were 76 persons ( control group ) and 69 persons ( vitamin D group ) . There was no difference in the incidence of hip fracture ( p = 0.66 , log-rank test ) , or in the incidence of all nonvertebral fractures ( p = 0.60 , log-rank test ) in the vitamin D group compared with the control group . Compared with the control group , persons in the vitamin D group increased their serum 25-hydroxyvitamin D concentration with 22 nmol/liter ( p = 0.001 ) . In conclusion , we found that an intervention with 10 microg of vitamin D3 alone produced no fracture-preventing effect in a nursing home population of frail elderly people
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 .