Association between vitamin D supplementation and mortality: systematic review and meta-analysis

source extracted confidence: high 2026-04-09
#cholecalciferol #dietary-supplements #ergocalciferols #humans #mortality

Association between vitamin D supplementation and mortality: systematic review and meta-analysis

Zhang et al., 2019 | BMJ | Meta Analysis

Citation

Zhang Yu, Fang Fang, ... Faramand Andrew. Association between vitamin D supplementation and mortality: systematic review and meta-analysis. BMJ. 2019-Aug-12;366:l4673. doi:10.1136/bmj.l4673

Abstract

OBJECTIVE: To investigate whether vitamin D supplementation is associated with lower mortality in adults. DESIGN: Systematic review and meta-analysis of randomised controlled trials. DATA SOURCES: Medline, Embase, and the Cochrane Central Register from their inception to 26 December 2018. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Randomised controlled trials comparing vitamin D supplementation with a placebo or no treatment for mortality were included. Independent data extraction was conducted and study quality assessed. A meta-analysis was carried out by using fixed effects and random effects models to calculate risk ratio of death in the group receiving vitamin D supplementation and the control group. MAIN OUTCOME MEASURES: All cause mortality. RESULTS: 52 trials with a total of 75 454 participants were identified. Vitamin D supplementation was not associated with all cause mortality (risk ratio 0.98, 95% confidence interval 0.95 to 1.02, I2=0%), cardiovascular mortality (0.98, 0.88 to 1.08, 0%), or non-cancer, non-cardiovascular mortality (1.05, 0.93 to 1.18, 0%). Vitamin D supplementation statistically significantly reduced the risk of cancer death (0.84, 0.74 to 0.95, 0%). 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. STUDY REGISTRATION: PROSPERO registration number CRD42018117823.

Key Findings

52 trials with a total of 75 454 participants were identified. Vitamin D supplementation was not associated with all cause mortality (risk ratio 0.98, 95% confidence interval 0.95 to 1.02, I2=0%), cardiovascular mortality (0.98, 0.88 to 1.08, 0%), or non-cancer, non-cardiovascular mortality (1.05, 0.93 to 1.18, 0%). Vitamin D supplementation statistically significantly reduced the risk of cancer death (0.84, 0.74 to 0.95, 0%). In subgroup analyses, all cause mortality was significantly lower in

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population See abstract
Sample Size 0
Age Range See abstract
Condition See abstract

MeSH Terms

  • Cholecalciferol
  • Dietary Supplements
  • Ergocalciferols
  • Humans
  • Mortality
  • Neoplasms
  • Randomized Controlled Trials as Topic
  • Vitamin D

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't, Systematic Review
  • Vertical: vitamin-d-mortality

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09