Vitamin intake reduce the risk of gastric cancer: meta-analysis and systematic review of randomized and observational studies

PLoS One. 2014 Dec 30;9(12):e116060. doi: 10.1371/journal.pone.0116060. eCollection 2014.

Abstract

Aim: The association between vitamin intake and gastric cancer (GC) has been widely debated due to the relatively weak evidence. In this study, a meta-analysis of prospective and well designed observational studies were performed to explore this association.

Methods: MEDLINE, Cochrane Library, and Sciencedirect were searched for studies of vitamin consumption and gastric cancer. This produced 47 relevant studies covering 1,221,392 human subjects. Random effects models were used to estimate summary relative risk (RR). Dose-response, subgroup, sensitivity, meta-regression, and publication bias analyses were conducted.

Results: The RR of gastric cancer in the group with the highest vitamin intake was compared to that of the lowest intake group. Total vitamin intake was 0.78 (95% CI, 0.71-0.83). In 9 studies that individuals were given doses at least 4 times above the tolerable upper intake (UL) vitamins, the RR was 1.20 (95% CI, 0.99-1.44). However, in 17 studies that individuals received doses below the UL, the RR was 0.76 (95% CI, 0.68-0.86). Dose-response analysis was conducted on different increments in different types of vitamins (vitamin A: 1.5 mg/day, vitamin C: 100 mg/day, vitamin E: 10 mg/day) intake with a significant reduction in the risk of gastric cancer, respectively, 29% in vitamin A, 26% in vitamin C, and 24% in vitamin E.

Conclusion: This meta-analysis clearly demonstrated that low doses of vitamins can significantly reduce the risk of GC, especially vitamin A, vitamin C, vitamin E.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't
  • Review
  • Systematic Review

MeSH terms

  • Dose-Response Relationship, Drug
  • Humans
  • Observational Studies as Topic
  • Randomized Controlled Trials as Topic
  • Risk
  • Stomach Neoplasms / prevention & control*
  • Vitamins / administration & dosage*

Substances

  • Vitamins

Grant support

This study was supported by National Science Foundation of China (No. 81172341). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.