CHICAGO (AP) -- A study suggests that women who drink just three alcoholic beverages a week face a slightly higher chance of developing breast cancer when compared to women who don't drink.

The study involved more than 100,000 U.S. nurses.The link between alcohol and breast cancer isn't new. But most previous studies found no increased risk among light drinkers.

Experts say the new research provides compelling evidence of the increased risk, because it followed so many women for up to nearly 30 years.

Still, the study only shows an association between alcohol and breast cancer, and it doesn't prove that drinking causes the disease. For example, experts say, the light drinkers may be less active than the nondrinkers, or