The team of Kaiser Permanente researchers studied the drinking habits of over 70,000 women of varying ethnicities who had supplied information during health exams between 1978 and 1985. By the year 2004, 2,800 of these women were diagnosed with breast cancer.
Researchers analyzed three aspects of the records; they compared alcohol intake among women who favored specific beverages, the frequency of drinking each beverage type, and the role of total alcoholic intake compared with women who drank less than one drink a day. The results found no difference among the varying types of alcoholic beverages, even when wine was divided into red and white.
Researchers found the risk of breast cancer rose by 30 percent in women who drank more than three drinks a day. They claim that "We think that the heart protection benefit from alcohol is real, and is probably derived largely from alcohol-induced higher HDL or "good" cholesterol, reduced blood clotting and reduced diabetes." However, they warn "Our findings provide more evidence for why heavy drinkers should quit or cut down."