The relationship between coffee consumption and the risk of gastric cancer; a systematic review and meta-analysis

Introduction: Stomach cancer is among five common malignancies whose prevalence and incidence are considerably associated with our dietary regime. Thus, the present study aims to conduct a systematic review and meta-analysis to evaluate the relationship between coffee drinking and the risk of stomach cancer. Materials and Methods: A comprehensive literature search of the databases, including Barakat Knowledge Network System, Cochrane, IranDoc, Web of Science, PubMed, SID, Magiran, Scopus, and Google Scholar web browser was conducted using standard keywords. Data analysis of this meta-analysis was conducted using STATA 14 software and P<0.05 was considered as a significant level for tests. Results: A total of 24 studies with a sample size of 990605 were reviewed which showed drinking coffee prevents stomach cancer [OR=0.89, (95% CI: 0.82, 0.98]. However, subgroup analysis by gender found no significant statistical relationship between coffee consumption and stomach cancer risk regarding male or female gender. However, the statistically significant relationship between coffee drinking and stomach cancer risk was assessed in several countries, including Korea, Turkey, Uruguay, Venezuela, and Singapore, with the largest effect being reported in Turkey [OR=0.51 (95% CI: 0.39,0.67]. Conclusion: Coffee consumption prevents and reduces the risk of developing stomach cancer.