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 annual intramuscular vitamin D on fracture risk in elderly men and women--a population-based, randomized, double-blind, placebo-controlled trial.
OBJECTIVES Low trauma fractures in older people incur enormous physical , social and economic costs . Previous research indicates that an annual intramuscular injection of vitamin D may reduce fracture rates in this group . This strategy requires validation in a population setting . METHODS R and omized , double-blind , placebo-controlled trial of 300,000 IU intramuscular ( i.m . ) vitamin D2 ( ergocalciferol ) injection or matching placebo every autumn over 3 years . 9440 people ( 4354 men and 5086 women ) aged 75 yrs and over were recruited from general practice registers in Wessex , Engl and . Primary outcome measure was all non-vertebral fracture . Secondary outcomes were hip and wrist fractures , and all falls . RESULTS 585 subjects had incident non-spine fractures  ( hip 110 , wrist 116 , ankle 37 ) . Hazard ratios ( HRs ) for fracture in the vitamin D group were : 1.09 [ 95 % confidence interval ( CI ) 0.93 - 1.28 , P = 0.29 ] for any first fracture , 1.49 ( 95 % CI 1.02 - 2.18 , P = 0.04 ) for hip and 1.22 ( 95 % CI 0.85 - 1.76 , P = 0.28 ) for wrist . There was no effect on falls : HR 0.98 ( 0.93 - 1.04 ) . No protective effect was observed in any subgroup when the cohort was stratified by sex , age , previous fracture or mobility . CONCLUSIONS An annual i.m . injection of 300,000 IU vitamin D2 is not effective in preventing non-vertebral fractures among elderly men and women resident in the general population
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 .