Association between zinc intake and risk of digestive tract cancers: a systematic review and meta-analysis

Clin Nutr. 2014 Jun;33(3):415-20. doi: 10.1016/j.clnu.2013.10.001. Epub 2013 Oct 10.


Background & aims: Association between zinc intake and digestive tract cancers risk has been reported in several epidemiological studies, while the results were controversial. The aim of our study was to get a systemic review of this issue.

Methods: PUBMED and EMBASE were searched up to April 2013, supplemented with manual-screening for relevant articles. Two independent reviewers independently extracted data from eligible studies, risk ratio (RR) or odds ratio (OR) with 95% CIs for the highest versus lowest categories of zinc intake was adopted. Either a fixed- or a random-effects model was adopted to estimate overall odds ratios. Besides, dose-response, subgroup, and publication bias analyses were applied.

Results: Nineteen studies with approximately 400,000 participants were included in this meta-analysis. The pooled relative risk (RR) of overall digestive tract cancers for the highest versus lowest categories of zinc intake was 0.82 (95% CI: 0.70-0.96; p = 0.013). Comparing the highest with lowest categories, higher zinc intake was significantly associated with reduced colorectal cancer risk (pooled RR = 0.80, 95% CI: 0.70-0.92; p = 0.002), while zinc intake was not statistically associated with gastric cancer risk (pooled RR = 0.91, 95% CI: 0.64-1.29; p = 0.581) or esophageal cancer risk (pooled RR = 0.72, 95% CI: 0.44-1.17; p = 0.187). However, subgroup analyses showed that zinc intake was significantly associated with esophageal cancer risk and gastric cancer risk in Asia, but not in America and Europe.

Conclusions: Dietary zinc intake was inversely associated with digestive tract cancers, especially colorectal cancer risk in this study.

Keywords: Digestive tract cancers; Meta-analysis; Zinc.

Publication types

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

MeSH terms

  • Colorectal Neoplasms / prevention & control*
  • Diet
  • Dietary Supplements*
  • Esophageal Neoplasms / prevention & control*
  • Humans
  • Risk Factors
  • Stomach Neoplasms / prevention & control*
  • Zinc / administration & dosage*


  • Zinc