Recent, well-designed studies now confirm that alcohol use probably increases a woman's chances of developing breast cancer, and, most surprisingly, that it doesn't take much to have an effect. While this conclusion may seem like bad news, it offers women another way to protect themselves, with specifics about how much alcohol is too much, at what age, and which alcoholic beverages may cause the most trouble.

Of course, the two greatest risk factors for breast cancer – being female and growing older – can't be changed, so women should follow the American Cancer Society's guidelines for the early detection of breast cancer. These include clinical breast exams as part of a periodic health checkup, annual mammograms beginning at age 40, and the optional use of breast self exams.

The most recent proof that alcohol plays an important role in breast cancer came from the ACS Cancer Prevention Study (CPS II) which looked at women who died of the disease.

Lead author Heather Feigelson, Ph.D. and colleagues reported that less than one drink a day on average increased a postmenopausal woman’s chances of dying from breast cancer by 30% compared to women who did not consume any alcohol.

This large study, performed by the American Cancer Society and which followed women in the United States for over 14 years, did not show any evidence that women who were either about to enter menopause or were premenopausal had any increased risk of dying from breast cancer due to alcohol use.

However, other studies suggest that premenopausal women who drink alcohol do have an increased risk of breast cancer, so women in this younger group cannot yet dismiss the link between alcohol and breast cancer

How much alcohol does it take to increase a woman’s chances of getting breast cancer? No one knows for certain, but even small amounts seem to make matters worse.

One study found that for each 10 grams of alcohol consumed a day, the lifetime risk of a woman developing breast cancer increases by almost 10% (there are about 15 grams of alcohol in the usual single alcoholic beverage).

For the average woman who has one drink a day, this means that her chances of being diagnosed with breast cancer during her lifetime would go from one in eight (12.5%) to about one in seven (about 14.25 %).

It doesn’t appear that the type of alcohol a woman drinks makes any difference. Beer, wine, and liquor all increase the risk of breast cancer, according to several recent studies.

Some researchers were hopeful that red wine, which has health benefits in other conditions such as heart disease, would not increase the risk of breast cancer. But that does not appear to be the case.

What you can do now depends on how much risk you are willing to accept when it comes to breast cancer.

Some women will find they can live with the small increased risk from an occasional drink. Experts Keith W. Singletary PhD and Susan M. Gapstur, PhD offered guidance in the Journal of the American Medical Association, “For those considered sporadic or occasional social drinkers (less than one drink per day), alcohol consumption is unlikely to significantly affect breast cancer risk.”

On the other hand, if you are a person who wants to do everything possible to decrease your risk of breast cancer, then avoiding alcohol should be part of your personal program.

Each woman should discuss any possible heart benefits of alcohol use with her primary care provider.

"Take a careful look at your risk factors and your family history," advises Feigelson, who's also a senior epidemiologist at the American Cancer Society. "Keep in mind we have lots of information about ways you can reduce your risk for both breast cancer and heart disease through exercise and proper diet."

The Bottom Line: It always pays to be prudent when it comes to your health, and that applies to alcohol and breast cancer. Excessive drinking will cause problems, and not only with breast cancer. But an occasional alcoholic beverage is unlikely to make a large difference in a woman’s risk profile for this disease, especially if you have a healthy diet, a healthy weight, and get regular exercise.

Sources:

"Alcohol and Breast Cancer," Keith Singletary, PhD, and Susan Gapstur, PhD, Journal of the American Medical Association (Vol. 286, No. 17: 2143-2151)
"Alcohol Consumption Increases The Risk Of Fatal Breast Cancer" Heather Feigelson, PhD, Cancer Causes and Control, December 2002