The research showing that alcohol increases the risk of colorectal cancer is clear. But now a large new study suggests that people who have a family history of colorectal cancer may be especially susceptible to the effects of alcohol increasing their risk of the cancer.
The study was published in the American Journal of Clinical Nutrition and you can read the abstract here. (One of the authors, Harvard University researcher Edward Giovannucci, spoke at last year’s AICR Research Conference.)
In the study, researchers looked at alcohol consumption patterns among approximately 135,000 men and women, starting in 1980 (for the women) and 1986 (for the men). Every few years the participants answered questionnaires about how much alcohol they drank and reported whether they had been diagnosed with colon cancer.
After following the participants through 2006, the study first looked at the whole population. It found that those who drank the most alcohol — over 30 grams of alcohol per day on average, which is about 2 drinks – had an increased risk of colon cancer when compared to those who didn’t drink any alcohol.
Yet the link was most pronounced among the drinkers with a parent and/or sibling who had colorectal cancer. Among people with a family history of colorectal cancer, those who drank over 30 grams of alcohol daily had slightly over double the risk of colon cancer — 100 percent more — compared to the nondrinkers. Among those with no family history of colorectal cancer, the risk of drinking over 30 grams of alcohol daily was linked to a 23 percent higher risk of the cancer compared to the nondrinkers.
Last year, AICR/WCRF’s continuous update project released its report on the evidence linking colorectal cancer risk to diet, weight, and physical activity. Here is a summary of the report’s findings.