Heavy drinkers 25% more likely to develop bowel cancer: Study
Heavier drinkers were around 25 per cent more likely to develop bowel cancer and nearly twice as likely to develop rectal cancer. The results come as doctors and scientists are trying to explain why bowel cancer rates are rising in younger adults.
New Delhi: Alcohol has long been marketed with mixed messages—occasionally praised for heart health while repeatedly flagged as a cancer risk. Now, a large long-term study from the United States adds new clarity, identifying how much drinking may raise the likelihood of developing bowel cancer.
Researchers from the US National Cancer Institute tracked more than 88,000 healthy adults over two decades. During that period, 1,679 participants were diagnosed with bowel cancer. The findings, published in the journal Cancer, suggest that people who consumed an average of 14 or more alcoholic drinks per week over their lifetime had a significantly higher cancer risk compared with those who drank rarely.
According to the analysis, heavier drinkers were around 25 per cent more likely to develop bowel cancer and nearly twice as likely to develop rectal cancer. The results come as doctors and scientists are trying to explain why bowel cancer rates are rising in younger adults. Previous data show a noticeable increase in cases among people aged 25 to 49 over recent decades.
The study, however, also delivered some encouraging news. People who stopped drinking—even later in life—did not appear to carry the same elevated cancer risk. Former drinkers showed no increased risk compared with light drinkers and were also less likely to develop adenomas, which are non-cancerous growths that can sometimes become malignant.
Dr Erikka Loftfield, a senior researcher involved in the study, said the findings help clarify how drinking habits across a lifetime influence cancer risk. Although the data on former drinkers was limited, it was good enough to ensure that quitting alcohol helped reduce long-term risks. Scientists also believe that alcohol contributes to bowel cancer risk through severe biological processes.
When the body breaks down alcohol, it releases a toxic byproduct known as acetaldehyde, which inflames the colon and damages DNA. Alcohol also hampers folate absorption, a nutrient that helps with DNA repair. It slows down digestion, thereby prolonging the colon's exposure to harmful substances.
Health experts continue to stress that alcohol is linked to multiple cancers, including those of the bowel, breast, and liver. While moderate drinking is common in many cultures, researchers say the latest findings highlight the benefits of limiting intake—or quitting altogether—to reduce cancer risk.