Background: Alcohol consumption is a potential risk factor for gastric cancer. However, findings from cohort studies that examined the relationship between alcohol consumption and gastric cancer risk among Japanese population are not conclusive.

Methods: A total of 54,682 Japanese men and women participating in the Japan Collaborative Cohort study completed a questionnaire, including alcohol consumption information. The Cox proportional hazard model was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs).

Results: After a median 13.4-year follow-up, we documented 801 men and 466 women incident cases of gastric cancer. Alcohol consumption was associated with increased risk of gastric cancer among men (HRs in ex-drinkers and current alcohol consumption of <23 g, 23–<46 g, 46–<69 g, and ≥69 g/d categories versus never drinkers were 1.82; 95% CI, 1.38–2.42, 1.41; 95% CI, 1.10–1.80, 1.47; 95% CI, 1.17–1.85, 1.88; 95% CI, 1.48–2.38, and 1.85; 95% CI, 1.35–2.53, respectively, and that for 10 g increment of alcohol consumption after excluding ex-drinkers was 1.07; 95% CI, 1.04–1.10). The association in men was observed for cardia and non-cardia gastric cancer (HRs in the highest alcohol consumption category versus never drinkers were 9.96; 95% CI, 2.22–44.67 for cardia cancer and 2.40; 95% CI, 1.64–3.52 for non-cardia cancer). However, no such trend was observed in women.

Conclusions: Alcohol consumption is associated with increased risk of gastric cancer among Japanese men, regardless of anatomical subsite of the cancer.