Baseline alcohol consumption, type of alcoholic beverage and risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition-Norfolk study

Excessive alcohol consumption has been associated with increased risk of colorectal cancer (CRC). However, the effect of modest alcohol consumption or of particular types of beverages on CRC risk remains unclear. We examined whether consumption of total alcohol or specific types of alcoholic beverages relate to overall or site-specific CRC risk in a prospective population study of 24,244 participants and 407 incident CRC cases after 11 years of follow-up. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models. Consumption of specific alcoholic beverages at baseline was collected using a detailed health and lifestyle questionnaire. Total alcohol consumption was not associated with CRC risk before or after adjustment for age, sex, weight, height, and smoking status (HR: 0.80, 95% CI: 0.51-1.26 for alcohol consumption of ≥21 units/week compared with non-drinkers), and further adjustment for education level, exercise, family history of CRC, and dietary factors did not significantly alter the risk estimates (HR: 0.70, 95% CI: 0.44-1.13). No significant associations were observed between consumption of specific alcoholic beverages (beer, sherry, or spirits) and CRC risk when compared with non-drinkers after adjustment for lifestyle and dietary factors. Daily consumption of ≥1 unit of wine appeared inversely related to CRC risk (HR: 0.61, 95% CI: 0.40-0.94). No evidence was found for sex-specific relationships, and further exclusion of cases incident within 3 years of baseline did not change the associations observed. In this population-based UK cohort, we did not find any significant adverse effect of alcohol over the moderate range of intake on colorectal cancer risk.