Summary:
Colorectal cancer (CRC) is one of the most common cancers in the United States. Rates have risen among adults younger than 55 years since the mid-1990s. Alcohol consumption has been identified as a preventable cancer risk factor, and alcoholic beverages are classified as carcinogenic to humans. Most epidemiological evidence has relied on cohort studies assessing recent alcohol intake, while fewer studies have examined lifetime drinking patterns. This study is a prospective cohort analysis using data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, which enrolled 154,887 adults aged 55-74 years. Participants provided demographic, lifestyle, and dietary information, including alcohol intake across four life stages. Average lifetime alcohol consumption was calculated from age 18 years to baseline. CRC was identified during up to 20 years of follow-up. Among 12,327 participants with a negative baseline screening, 812 developed a benign growth (often a precursor to CRC) at follow-up. In the larger cohort of 88,092 participants, 1,679 CRC cases occurred over 20 years. Compared with individuals consuming one drink or less per week, current drinkers with an average lifetime intake of 14 or more drinks per week had a higher risk of CRC, with the strongest association observed for rectal cancer. Consistent heavy drinking over time was also associated with increased CRC risk. In contrast, former drinkers had lower odds of non-advanced adenoma compared with very light current drinkers. Moderate current intake (seven to fewer than 14 drinks per week) was associated with a modestly lower CRC risk. In summary, this prospective cohort study suggests that sustained heavy alcohol consumption and higher lifetime intake are associated with increased CRC risk, while alcohol cessation may reduce adenoma risk.
Abstract:
Background: Alcohol drinking is associated with higher colorectal cancer (CRC) risk, but research on lifetime alcohol drinking is limited. The objective of the current study was to estimate the association of lifetime alcohol drinking with incident colorectal adenoma and cancer. Methods: US adults enrolled in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial reported alcohol intake during four age periods. Average lifetime alcohol intake was calculated as average drinks per week from age 18 years until study baseline. Alcohol intake patterns were defined by past and current drinking frequency. Among 12,327 participants with a negative baseline screen, 812 had an adenoma on the second screen. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for incident adenoma. During 20 years of follow-up, 1679 incident CRC cases occurred among 88,092 participants. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% CIs for CRC. Results: Current drinkers with an average lifetime alcohol intake of 14 or more drinks per week, compared with one drink or less per week, had a higher risk of CRC (HR, 1.25; 95% CI, 1.01–1.53), especially rectal cancer (HR, 1.95; 95% CI, 1.17–3.28). Consistent heavy drinking versus light drinking was positively associated with CRC risk (HR, 1.91; 95% CI, 1.17–3.12). Compared with current drinkers averaging less than one drink per week, former drinkers had lower odds of nonadvanced adenoma (OR, 0.58; 95% CI, 0.39–0.84). Current drinkers averaging from seven to less than 14 drinks compared with less than one drink per week had a lower risk of CRC (HR, 0.79; 95% CI, 0.64–0.97), especially distal colon cancer (HR, 0.64; 95% CI, 0.42–1.00). Conclusions: Consistent heavy alcohol intake and higher average lifetime alcohol drinking may increase CRC risk, whereas cessation may lower adenoma risk. Associations may differ by tumor site.
Article Publication Date: 26/01/2026
DOI: 10.1002/cncr.70201
