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 .
Effects of Vitamin D Supplementation on Bone Mineral Density and Bone Markers in HIV-Infected Youth
Background : Low bone mineral density ( BMD ) is a significant comorbidity in HIV . However , studies evaluating vitamin D supplementation on bone health in this population are limited . This study investigates changes in bone health parameters after 12 months of supplementation in HIV-infected youth with vitamin D insufficiency . Methods : This is a r and omized , active-control , double-blind trial investigating changes in bone parameters with 3 different vitamin D3 doses [ 18,000 ( st and ard/control dose ) , 60,000 ( moderate dose ) , and 120,000 IU/monthly ( high dose ) ] in HIV-infected youth 8–25 years old with baseline serum 25-hydroxyvitamin D ( 25(OH)D ) concentrations < 30 ng/mL.  BMD and bone turnover markers were measured at baseline and 12 months . Results : One hundred two subjects enrolled . Over 12 months , serum 25(OH)D concentrations increased with all doses , but the high dose ( ie , 120,000 IU/monthly ) maintained serum 25(OH)D concentrations in an optimal range ( ≥30 or ≥20 ng/mL ) throughout the study period for more subjects ( 85 % and 93 % , respectively ) compared with either the moderate ( 54 % and 88 % , respectively ) or st and ard dose ( 63 % and 80 % , respectively ) . All dosing groups showed some improvement in BMD ; however , only the high-dose arm showed significant decreases in bone turnover markers for both procollagen type 1 aminoterminal propeptide ( −3.7 ng/mL ; P = 0.001 ) and & Bgr;-CrossLaps ( −0.13 ng/mL ; P = 0.0005 ) . Conclusions : High-dose vitamin D supplementation ( 120,000 IU/mo ) given over 12 months decreases bone turnover markers in HIV-infected youth with vitamin D insufficiency , which may represent an early , beneficial effect on bone health . High vitamin D doses are needed to maintain optimal serum 25(OH)D concentrations
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 .