Alcohol Consumption Increases the Risk of Colon Cancer

08/08/07 Experts at the American Institute for Cancer Research (AICR) welcomed the latest results from the world's largest study on diet and cancer. The new results, published online at the International Journal of Cancer, link alcohol consumption to an increased risk of colon cancer.

According to the study, those participants who reported consuming three or more alcoholic drinks per day had a 26 percent higher lifetime risk of colon cancers than non-drinkers. Smaller increases in risk were observed among those whose alcohol consumption was as low as one drink per day, underscoring the fact that alcohol is a significant risk factor for colon cancer.

These results support AICR's long-standing advice to limit alcohol consumption. The AICR guideline on alcohol reads: If alcohol is consumed at all, men should consume no more than two drinks per day and women no more than one.

To those members of the public concerned about how these results relate to studies showing that moderate consumption of alcohol benefits heart health, AICR offered some perspective.

"The key word is moderate," said AICR Nutrition Advisor Karen Collins, MS, RD. "The heart benefits that have been associated with alcohol occur at relatively low levels of consumption - the levels specified in the AICR guidelines.

"When it comes to alcohol and overall health we know one thing for sure - more is not better," Collins said.

The EPIC Study

The new results come from the largest study of diet and cancer ever undertaken. Called the European Prospective Investigation into Cancer and Nutrition, or EPIC, this ongoing cohort study is currently tracking the diets and disease rates of an unprecedented 521,483 individuals in 10 different European countries. Read more about the EPIC study, how it differs from US cohort studies, and why AICR experts believe it to be so authoritative, here.

Behind the Alcohol - Cancer Link

Alcohol has been linked to cancers of the colon and rectum for years, as well as several other cancers including those of the mouth and throat. Smokers who drink increase their risk of lung cancer significantly. Years of drinking can give rise to liver damage that leads to liver cancer. Alcohol as has also been designated a probable cause for breast cancer.

The reason for these links, experts say, has to do with the behavior of alcohol in the body. Alcohol is a pro-inflammatory, pro-oxidant substance. Sensitive tissues that are repeatedly exposed to it can get damaged in ways that spark the cancer process.

The breast cancer link seems to be a special case, however. Unlike other cancers associated with alcohol consumption, the cells of the breast are only indirectly exposed to alcohol. Yet the association keeps showing up, in study after study.

"The breast cancer link is particularly troubling and consistent, but its precise nature remains unclear," said Collins. "We do know that a man's body has more muscle and less fat than a woman's, so it's easier for him to dilute and metabolize the alcohol he drinks. Alcohol stays in a woman's bloodstream longer, and that may be one reason that women who consume even one drink a day have a slightly higher risk of breast cancer compared to non-drinkers."

Expert Report Will Help Dispel Confusion

On November 1st of this year, AICR and its international affiliate organizations will publish the most comprehensive assessment of the scientific literature on diet, physical activity and cancer risk ever undertaken.

That report, Food, Nutrition, Physical Activity and the Prevention of Cancer: A Global Perspective, will synthesize data from thousands of studies like the EPIC study to provide guidelines for the public and for the scientific/medical community. It will provide answers to questions about nutrition and cancer that are based on a thorough review of the available science.