CHICAGO - Whether sipping beer, wine, or whiskey, women who drink just three alcoholic beverages a week face slightly higher chances for developing breast cancer compared with teetotalers, a study of more than 100,000 US nurses found.
The link between alcohol and breast cancer isn’t new, but most previous studies found no increased risk for breast cancer among light drinkers. The new research provides compelling evidence because it followed so many women for up to almost 30 years, specialists said.
Still, the study only shows an association between alcohol and breast cancer; it doesn’t prove that drinking causes the disease. There could be some other reason light drinkers appeared to be at higher risk: maybe they were less active than nondrinkers or had unhealthy diets, said Dr. Susan Love, a breast cancer expert and specialists who runs a Santa Monica, Calif.-based research foundation.
Women in the study who averaged three to six drinks a week throughout the study had a 15 percent higher chance of developing breast cancer than nondrinkers. That risk means, for example, that among women in their 50s, who on average face a 2.38 percent risk for breast cancer, light drinking would result in 4 additional cases of breast cancer per 1,000 women
Risks increased by 10 percent for every 10 grams of alcohol consumed daily. That’s equal to a little less than one 12-ounce bottle of beer, a 4-ounce glass of wine, or a shot of whiskey. The increasingly elevated risks were a little higher than seen in other research.
Given research suggesting that drinking moderate amounts of alcohol including red wine may protect against heart disease, deciding whether to avoid alcohol is a personal choice that should be based on a woman’s other risks for breast cancer and heart disease, the researchers said.
The study appears in today’s Journal of the American Medical Association.