A significant study has found that heavy drinking over a lifetime substantially increases the risk of colorectal cancer (CRC). Conducted using data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, researchers have linked cumulative alcohol consumption to high rates of precancerous polyps and invasive cancers, especially among current drinkers.
The findings, published in the journal Cancer in March 2026, highlight that individuals with a lifetime average of consuming 14 or more alcoholic drinks per week face a 25% higher risk of developing colorectal cancer compared to those who drink less than one drink per week. This elevated risk is particularly pronounced for rectal cancer, where heavy drinkers are nearly twice as likely to be affected.
Understanding the Relationship Between Alcohol and Colorectal Cancer
While colorectal cancer remains a leading cause of cancer mortality, particularly in the United States, the incidence rates have been declining overall. However, there has been a concerning increase in diagnoses among adults under 55. The International Agency for Research on Cancer (IARC) classifies alcoholic beverages as carcinogenic, directly linking them to colorectal cancer.
Previous studies have often relied on recent measurements of alcohol consumption, typically focusing on the past year. This approach overlooks the long-term nature of cancer development, which often unfolds over decades. The current study aims to fill this gap by reconstructing participants’ drinking histories starting from age 18, thus providing a more comprehensive view of alcohol’s impact on health.
Methodology and Key Findings
The study analyzed the data from 12,327 participants who underwent flexible sigmoidoscopy screening and a broader cohort of 88,092 individuals monitored for clinically diagnosed cancer. Participants provided detailed sociodemographic and medical histories, including information on their alcohol consumption across four age groups: 18–24, 25–39, 40–54, and 55 and older.
Analysis categorized drinkers based on their lifetime average consumption, allowing researchers to assess the impact of different drinking patterns on cancer risk. Those identified as consistent heavy drinkers throughout adulthood demonstrated a 91% higher risk of colorectal cancer compared to consistent light drinkers.
The study also found a nonlinear relationship for moderate drinking. Participants averaging 7 to <14 drinks per week showed a lower risk of colorectal cancer, particularly for distal colon cancer. However, researchers cautioned that this might reflect residual confounding or differences in health behaviors rather than indicating a protective effect of moderate alcohol consumption. Another noteworthy finding was the association between alcohol cessation and reduced odds of developing nonadvanced adenomas, which are precursors to cancer. Former drinkers had significantly lower odds of these early-stage lesions compared to very light current drinkers. In summary, the study provides robust evidence that cumulative lifetime alcohol exposure is a significant risk factor for colorectal cancer. This reinforces the importance of public health messaging regarding alcohol consumption, emphasizing the long-term risks associated with heavy drinking. While the observational nature of the research limits the ability to draw definitive causal conclusions, the findings suggest that lifestyle modifications, such as reducing alcohol intake, may positively influence long-term health outcomes. The study's limitations include reliance on self-reported alcohol intake and a sample that predominantly comprises white, educated individuals. As the research community continues to explore the connections between lifestyle factors and cancer risk, these findings underscore the necessity for further investigation into how alcohol consumption patterns can be modified to reduce cancer incidence.
