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 calcium and vitamin D supplementation on hip bone mineral density and calcium-related analytes in elderly ambulatory Australian women: a five-year randomized controlled trial.
CONTEXT Effects of long-term calcium , with or without vitamin D , on  hip bone mineral density ( BMD ) and bone turnover in sunny climates have not been reported . OBJECTIVE The aim was to evaluate the effect of vitamin D added to calcium supplementation on hip dual-energy x-ray absorptiometry BMD and calcium-related analytes . DESIGN , SETTING , AND PARTICIPANTS The study was a 5-yr r and omized , controlled , double-blind trial of 120 community-dwelling women aged 70 - 80 yr . INTERVENTIONS The interventions were 1200 mg/d calcium with placebo vitamin D ( Ca group ) or with 1000 IU/d vitamin D2 ( CaD group ) , or double placebo ( control ) . MAIN OUTCOME MEASURES Hip BMD , plasma 25-hydroxyvitamin D , biomarkers of bone turnover , PTH , and intestinal calcium absorption were measured . RESULTS Hip BMD was preserved in CaD ( -0.17 % ) and Ca ( 0.19 % ) groups but not controls ( -1.27 % ) at yr 1 and maintained in the CaD group only at yr 3 and 5 . The beneficial effects were mainly in those with baseline 25-hydroxyvitamin D levels below the median ( 68 nmol/liter ) . At yr 1 , compared with controls , the Ca and CaD groups had 6.8 and 11.3 % lower plasma alkaline phosphatase , respectively ( P < or=0.02 ) , and 28.7 and 34.5 % lower urinary deoxypyridinoline to creatinine ratio , respectively ( P < or=0.05 ) . At 5 yr , this suppression was maintained only in the CaD group . CaD reduced PTH at 3 and 5 yr cf . controls ( 27.8 and 31.3 % , P < or=0.005 ) in those with baseline PTH levels above the median ( 3.6 pmol/liter ) . Therapy did not affect intestinal calcium absorption at high carrier loads . CONCLUSIONS Addition of vitamin D to calcium has long-term beneficial effects on bone density in elderly women living in a sunny climate , probably mediated by a long-term reduction in bone turnover rate
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 .