The Women's Health Resource. On the web since 1997.

More Evidence: Alcohol Increases Breast Cancer Risk (dateline March 31, 2002)

A new study adds to a growing body of evidence that finds that alcohol consumption increases the risk of breast cancer, especially in post-menopausal women. The study analyzed dietary and beverage habits of over 60,000 women and found that those who consumed alcohol had a 30% higher risk of developing breast cancer, compared to women who did not drink. The study also made a surprisingly finding, that a "Western diet," consisting of high quantities of red meat and fattening snacks, did not affect breast cancer risk. While the link between diet and breast cancer risk remains unclear, the study provides more solid evidence that alcohol increases breast cancer risk.

The study, which involved 61,463 Swedish women, was conducted by Paul Terry, PhD, of Albert Einstein College of Medicine, and his colleagues from Sweden. The researchers first identified the major dietary patterns among the women and then attempted to determine whether those patterns influenced breast cancer risk. The researchers divided the women’s dietary habits into three dietary categories: the "Western diet," which consisted of red meat, whole milk, snacks, etc.; the "Healthy diet," which included fruits, vegetables, whole grains, fish, chicken, etc.; and the "Drinker diet," which included a large amount of beer, wine, and/or liquor.

While there was some overlap in the dietary patterns, the researchers found that the women who drank high amounts of alcohol were 30% more likely to develop breast cancer than the women who did not drink alcohol. The risk of breast cancer among drinkers was less in women under age 50, which is consistent with other studies that have found that alcohol has a larger influence on breast cancer risk in post-menopausal women.

Interestingly, the study found that the type of foods women consumed did not have an effect on their risk of breast cancer. For example, women who consumed a fatty "Western diet" were no more likely to develop breast cancer than the women who followed a "Healthy diet." This contradicts some previous studies that have linked a high-fat diet to an increased risk for breast cancer. However, because a fatty diet increases the risk of heart disease, colon cancer, and other diseases, it is still associated with serious health consequences.

Dr. Terry and his colleagues’ findings on alcohol and breast cancer confirm previous studies. For example, in a 1999 study reported in The Journal of the American Medical Association, researchers analyzed data from 322,647 women (including 4,335 women who had breast cancer) in Canada, The Netherlands, Sweden, and the United States. Women who consumed two to five alcoholic beverages each day were found to have a 41% increased risk of developing invasive breast cancer compared to women who do not drink.

In another study published in a May 2001 issue of the Journal of the National Cancer Institute, researchers also found that moderate alcohol intake increases the risk of breast cancer. In that study, researchers followed over 50 women for eight-week periods and found that the women who consumed alcohol during that time had higher levels of hormones that have been linked to breast cancer.

However, other studies suggest that the relationship between alcohol and breast cancer risk is less clear. For example, in a study published in the July 2001 issue of Epidemiology, researchers found that consuming more than one half of a glass of alcohol per day and having low amounts of the B vitamin folate may increase the risk of breast cancer. Folate is found in green leafy vegetables, orange juice, dried beans and peas, and some cereals. While Dr. Thomas Sellers of the Mayo Clinic and his colleagues note that alcoholic beverages slightly increase the risk of breast cancer, they suggest that an adequate intake of folate might help counteract the risk.

Dr. Terry and his colleagues conclude that alcohol moderately increases the risk for breast cancer. Thus, alcohol joins a list of several other breast cancer risk factors, which include:

Physicians recommend that women become aware of the risk factors for breast cancer and follow the established guidelines for breast health. Those guidelines include monthly breast self-exams, regular clinical breast exams, and screening mammograms for women 40 years of age and older.

Additional Resources and References