Consumption of large amounts of Allium vegetables reduces risk for gastric cancer in a meta-analysis

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#allium #confounding-factors-epidemiologic #diet #evidence-based-medicine #humans

Consumption of large amounts of Allium vegetables reduces risk for gastric cancer in a meta-analysis

Zhou et al., 2011 | Gastroenterology | Meta Analysis

Citation

Zhou Yong, Zhuang Wen, ... Wu Xiao-Ting. Consumption of large amounts of Allium vegetables reduces risk for gastric cancer in a meta-analysis. Gastroenterology. 2011-Jul;141(1):80-9. doi:10.1053/j.gastro.2011.03.057

Abstract

BACKGROUND & AIMS: The chemopreventive effects of Allium vegetables (onions, garlic, shallots, leeks, chives, and so forth) have been studied extensively, although their effect on gastric cancer risk is controversial. We performed a meta-analysis of cohort and case-control studies to analyze this association. METHODS: We searched MEDLINE for studies of Allium vegetable consumption and gastric cancer that were published in any language, from January 1, 1966, to September 1, 2010. We analyzed 19 case-control and 2 cohort studies, of 543,220 subjects. We pooled the relative risks from individual studies using a random-effects model and performed dose-response, heterogeneity, and publication bias analyses. RESULTS: In a pooled analysis of all studies, consumption of large amounts of Allium vegetables (in a comparison of the highest and lowest consumption groups) reduced the risk for gastric cancer (odds ratio, 0.54; 95% confidence interval, 0.43-0.65). Specific analyses for onion, garlic, leek, Chinese chive, scallion, garlic stalk, and Welsh onion yielded similar results, except for onion leaf. The estimated summary odds ratio for an increment of 20 g/day of Allium vegetables consumed (approximately the average weight of 1 garlic bulb) was 0.91 (95% confidence interval, 0.88-0.94), based on case-control studies from the dose-response meta-analysis. CONCLUSIONS: In a meta-analysis, consumption of high levels of Allium vegetables reduced the risk for gastric cancer risk. Because of potential confounding factors and exposure misclassification, further studies are required to establish this association.

Key Findings

In a pooled analysis of all studies, consumption of large amounts of Allium vegetables (in a comparison of the highest and lowest consumption groups) reduced the risk for gastric cancer (odds ratio, 0.54; 95% confidence interval, 0.43-0.65). Specific analyses for onion, garlic, leek, Chinese chive, scallion, garlic stalk, and Welsh onion yielded similar results, except for onion leaf. The estimated summary odds ratio for an increment of 20 g/day of Allium vegetables consumed (approximately the a

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population See abstract
Sample Size 543220
Age Range See abstract
Condition See abstract

MeSH Terms

  • Allium
  • Confounding Factors, Epidemiologic
  • Diet
  • Evidence-Based Medicine
  • Humans
  • Odds Ratio
  • Publication Bias
  • Risk Assessment
  • Risk Factors
  • Stomach Neoplasms
  • Vegetables

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't
  • Vertical: garlic

Provenance

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