In subgroup analyses , all cause mortality was significantly lower in trials with vitamin D3 supplementation than in trials with vitamin D2 supplementation ( P for interaction=0.04 ) ; neither vitamin D3 nor vitamin D2 was associated with a statistically significant reduction in all cause mortality .
CONCLUSIONS Vitamin D supplementation alone was not associated with  all cause mortality in adults compared with placebo or no treatment .
Vitamin D supplementation reduced the risk of cancer death by 16 % .
Additional large clinical studies are needed to determine whether vitamin D3 supplementation is associated with lower all cause mortality .
OBJECTIVE To investigate whether vitamin D supplementation is associated with lower mortality in adults .
Calcitriol treatment is not effective in postmenopausal osteoporosis.
STUDY OBJECTIVE To determine if calcitriol is an effective treatment in postmenopausal osteoporosis . DESIGN Double-blind , r and omized clinical trial of 2 years ' duration . SETTING University medical center with patients recruited by media announcements . PATIENTS Eighty-six postmenopausal women with vertebral compression fractures . INTERVENTIONS Patients were treated with calcitriol or placebo . Mean dose was 0.43 micrograms/d . Dietary calcium was 1000 mg/d ( 24.9 mmol/d ) . The medication dose and dietary calcium were adjusted for hypercalciuria or hypercalcemia . MEASUREMENTS AND MAIN RESULTS No significant differences between placebo and control groups were seen in the percent change in total body calcium ( 0.4 % + /- 1.0 compared with 0.0 % + /- 0.9 ) , single photon absorptiometry ( -0.5 % + /- 1.2 compared with -3.1 % + /- 0.9 ) or dual photon absorptiometry ( 0.0 % + /- 1.7 compared with -1.0 % + /- 2.2 ) . New fractures were seen in 16 % of the placebo group and 26 % of the calcitriol groups , so the difference in percent fractures was 10 % ( 95 % CI , -5.7 % to 25.7 % ) . Bone biopsies did not show changes in either group . The calcitriol group had significantly higher serum and urine calcium values , but renal function was not worse than in the placebo group . CONCLUSIONS Calcitriol is not an effective treatment for established postmenopausal osteoporosis
In subgroup analyses , all cause mortality was significantly lower in trials with vitamin D3 supplementation than in trials with vitamin D2 supplementation ( P for interaction=0.04 ) ; neither vitamin D3 nor vitamin D2 was associated with a statistically significant reduction in all cause mortality .
CONCLUSIONS Vitamin D supplementation alone was not associated with  all cause mortality in adults compared with placebo or no treatment .
Vitamin D supplementation reduced the risk of cancer death by 16 % .
Additional large clinical studies are needed to determine whether vitamin D3 supplementation is associated with lower all cause mortality .
OBJECTIVE To investigate whether vitamin D supplementation is associated with lower mortality in adults .