Coffee consumption is not associated with the risk of gastric cancer: An updated systematic review and meta-analysis of prospective cohort studies.

The results from epidemiological studies on the relationship between coffee consumption and gastric cancer risk are inconsistent and inconclusive. Based on the previous studies, we hypothesized that coffee consumption was not associated with the risk of gastric cancer. We aimed to test this hypothesis by conducting a meta-analysis to systematically review and quantify the relationship between coffee consumption and the risk of gastric cancer. Relevant prospective cohort studies were identified by a search of PubMed and Embase up to March 2021. A total of 18 independent prospective cohorts from 15 studies involving 1,608,760 participants and 3898 gastric cancer cases were included in this meta-analysis. A nonsignificant association with a pooled relative risk (RR) of 1.11 (95% confidence interval [CI], 0.99-1.25) was shown between coffee intake and the risk of gastric cancer. The dose-response analysis also suggested no significant effect on the risk of gastric cancer per 1 cup/d increment in coffee consumption (RR = 1.00; 95% CI, 0.99-1.01). No nonlinear association of gastric cancer risk with coffee consumption was found (P for nonlinearity = .17). In the subgroup analyses, significantly increased risk of gastric cancer was detected in the studies conducted in the United States (RR = 1.28; 95% CI, 1.03-1.58). In conclusion, coffee consumption had no effect on the risk of gastric cancer. However, the effect of coffee intake on persons in the United States must be further evaluated by additional high-quality and large-scale cohort studies.