Subgroup analyses in the observational studies indicated that risk of mortality was significantly higher in studies with lower baseline use of vitamin D supplements .
The effects observed for vitamin D3 supplementation remained unchanged when grouped by various characteristics .
However , for vitamin D2 supplementation , increased risks of mortality were observed in studies with lower intervention doses and shorter average intervention periods .
Conclusions Evidence from observational studies indicates inverse associations of circulating 25-hydroxyvitamin D with risks of death due to cardiovascular disease , cancer , and other causes .
Objective To evaluate the extent to which circulating biomarker and supplements of vitamin D are associated with  mortality from cardiovascular , cancer , or other conditions  , under various circumstances .
Effect of four monthly oral vitamin D3 (cholecalciferol) supplementation on fractures and mortality in men and women living in the community: randomised double blind controlled trial
Abstract Objective : To determine the effect of four monthly vitamin D supplementation on the rate of fractures in men and women aged 65 years and over living in the community . Design : R and omised double blind controlled trial of 100 000 IU oral vitamin D3 ( cholecalciferol ) supplementation or matching placebo every four months over five years . Setting and participants : 2686 people ( 2037 men and 649 women ) aged 65 - 85 years living in the general community , recruited from the British doctors register and a general practice register in Suffolk . Main outcome measures : Fracture incidence and total mortality by cause . Results : After five years 268 men and women had incident fractures , of whom 147 had fractures in common osteoporotic sites ( hip , wrist or forearm , or vertebrae ) . Relative risks in the vitamin D group compared with the placebo group were 0.78 ( 95 % confidence interval 0.61 to 0.99 , P=0.04 ) for any first fracture and 0.67 ( 0.48 to 0.93 , P=0.02 ) for first hip , wrist or forearm , or vertebral fracture . 471 participants died . The relative risk for total mortality in the vitamin D group compared with the placebo group was 0.88 ( 0.74 to 1.06 , P=0.18 ) . Findings were consistent in men and women and in doctors and the general practice population . Conclusion : Four monthly supplementation with 100 000 IU oral vitamin D may prevent fractures without adverse effects in men and women living in the general community . What is already known in this topic Vitamin D and calcium supplements are effective in preventing fractures in elderly women Whether isolated vitamin D supplementation prevents fractures is not clear What this paper adds Four monthly oral supplementation with 100 000 IU vitamin D reduces fractures in men and women aged over 65 living in the general community  Total fracture incidence was reduced by 22 % and fractures in major osteoporotic sites by 33
Subgroup analyses in the observational studies indicated that risk of mortality was significantly higher in studies with lower baseline use of vitamin D supplements .
The effects observed for vitamin D3 supplementation remained unchanged when grouped by various characteristics .
However , for vitamin D2 supplementation , increased risks of mortality were observed in studies with lower intervention doses and shorter average intervention periods .
Conclusions Evidence from observational studies indicates inverse associations of circulating 25-hydroxyvitamin D with risks of death due to cardiovascular disease , cancer , and other causes .
Objective To evaluate the extent to which circulating biomarker and supplements of vitamin D are associated with  mortality from cardiovascular , cancer , or other conditions  , under various circumstances .