Vitamin/mineral supplementation and cancer, cardiovascular, and all-cause mortality in a German prospective cohort (EPIC-Heidelberg)

Eur J Nutr. 2012 Jun;51(4):407-13. doi: 10.1007/s00394-011-0224-1. Epub 2011 Jul 22.

Abstract

Purpose: To prospectively evaluate the association of vitamin/mineral supplementation with cancer, cardiovascular, and all-cause mortality.

Methods: In the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg), which was recruited in 1994-1998, 23,943 participants without pre-existing cancer and myocardial infarction/stroke at baseline were included in the analyses. Vitamin/mineral supplementation was assessed at baseline and during follow-up. Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

Results: After an average follow-up time of 11 years, 1,101 deaths were documented (cancer deaths = 513 and cardiovascular deaths = 264). After adjustment for potential confounders, neither any vitamin/mineral supplementation nor multivitamin supplementation at baseline was statistically significantly associated with cancer, cardiovascular, or all-cause mortality. However, baseline users of antioxidant vitamin supplements had a significantly reduced risk of cancer mortality (HR: 0.52; 95% CI: 0.28, 0.97) and all-cause mortality (HR: 0.58; 95% CI: 0.38, 0.88). In comparison with never users, baseline non-users who started taking vitamin/mineral supplements during follow-up had significantly increased risks of cancer mortality (HR: 1.74; 95% CI: 1.09, 2.77) and all-cause mortality (HR: 1.58; 95% CI: 1.17, 2.14).

Conclusions: Based on limited numbers of users and cases, this cohort study suggests that supplementation of antioxidant vitamins might possibly reduce cancer and all-cause mortality. The significantly increased risks of cancer and all-cause mortality among baseline non-users who started taking supplements during follow-up may suggest a "sick-user effect," which researchers should be cautious of in future observational studies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antioxidants / adverse effects
  • Antioxidants / therapeutic use
  • Cardiovascular Diseases / diet therapy
  • Cardiovascular Diseases / mortality
  • Cardiovascular Diseases / prevention & control*
  • Cohort Studies
  • Dietary Supplements* / adverse effects
  • Female
  • Follow-Up Studies
  • Germany / epidemiology
  • Humans
  • Male
  • Middle Aged
  • Minerals / adverse effects
  • Minerals / therapeutic use*
  • Mortality
  • Neoplasms / diet therapy
  • Neoplasms / mortality
  • Neoplasms / prevention & control*
  • Nutrition Surveys
  • Proportional Hazards Models
  • Prospective Studies
  • Risk
  • Urban Health
  • Vitamins / adverse effects
  • Vitamins / therapeutic use*

Substances

  • Antioxidants
  • Minerals
  • Vitamins