Coffee consumption and head and neck cancer risk: a dose–response and site-specific meta-analysis

Head and neck cancers (HNCs) represent a major global health burden. While smoking, alcohol consumption, and human papillomavirus infection are established risk factors, the association between coffee intake and HNC risk remains inconclusive. This study evaluated the relationship between coffee consumption and HNC risk, with consideration of consumption levels and anatomical tumor subsites. A systematic search of four databases was conducted through March 2025. Two reviewers independently extracted data on study characteristics, coffee consumption (cups/day), and tumor subsites. Adjusted odds ratios (ORs) were pooled using meta-analytic methods, and analyses were stratified according to coffee intake levels. Thirty studies were included. Stratified analyses adjusted for confounders demonstrated protective effects at 3-4 cups/day [OR: 0.83, 95% confidence interval (CI): 0.70-0.99], more than 3 cups/day (OR: 0.63, 95% CI: 0.52-0.74), and more than 4 cups/day (OR: 0.71, 95% CI: 0.55-0.92), with an overall protective effect against HNC (OR: 0.78, 95% CI: 0.72-0.86, P = 0.0044). Site-specific analyses showed reduced risk for oral cancer (OR: 0.71, 95% CI: 0.63-0.80, P < 0.0001), pharyngeal cancer (OR: 0.80, 95% CI: 0.73-0.87, P < 0.0001), and upper aerodigestive tract cancer (OR: 0.78, 95% CI: 0.64-0.94, P = 0.0107), particularly among individuals consuming more than 3 cups/day; however, coffee consumption was associated with increased laryngeal cancer risk (OR: 1.13, 95% CI: 1.04-1.24, P = 0.0065). Higher coffee intake (≥3 cups/day) may reduce overall HNC risk while demonstrating important site-specific differences.