Caffeinated or decaffeinated coffee consumption and risk of cancer incidence: meta-analyses of prospective cohort studies

Many epidemiological studies have investigated the association between coffee consumption and risks for various types of cancer, yet results are conflicting. To determine the impact of coffee consumption on cancer incidence, we systematically reviewed high-quality prospective cohort studies for 10 major cancer types and performed meta-analyses of 63 studies from different countries. For each cancer type, we calculated summary relative risks using the DerSimonian–Laird random-effects model and assessed dose-response relationships. Our meta-analyses found that caffeinated coffee consumption, but not decaffeinated coffee, prevented liver and skin cancers, highlighting the significant role of caffeine in cancer prevention. Furthermore, both caffeinated and decaffeinated coffee prevented endometrial cancer, indicating the role of other active compounds in coffee. Collectively, our meta-analyses revealed that coffee consumption, particularly caffeinated coffee, prevents the incidence of liver, endometrial, and skin cancers in a dose-dependent manner, suggesting that coffee consumption has a large impact on public health.