It doesn't seem to matter whether the alcohol comes in the form of beer, wine, or spirits. . . when it comes to breast cancer, women who consume 3 or more drinks a day are at significantly greater risk for this disease.
BARCELONA, Spain, Sept. 27 -- Women who consume three of more alcoholic drinks a day have a 30% greater risk of developing breast cancer than women who averages one drink.
"It doesn't seem to matter whether the alcohol comes in the form of beer, wine, or spirits," said Yan Li, M.D., Ph.D., of Kaiser Permanente Medical Care in Oakland, Calif., and colleagues, reported at the European Cancer Care Organization meeting here.
They reviewed 70,033 records of patients at Kaiser Permanent from 1978 through 1985. By 2004, breast cancer had been diagnosed in 2,829 of these women. The role of specific beverage types was studied among 37,879 women consuming one drink per month. Of that group, 1,509 subsequently were diagnosed with breast cancer.
They found that 10,570 of the women were primarily wine drinkers, 3,783 preferred spirits, and 2,702 drank beer. Another 20,824 recorded no particular preference.
Dr. Li said she tried to find a relationship between breast cancer and the type of alcohol consumed but did not identify any significant correlations. For example, she said the relative risk of developing breast cancer when comparing women who had specific drink preferences with those with no drink preference was 1.06 for wine drinkers; 1.02 for liquor drinkers, and 1.02 for beer drinkers. The confidence limits crossed unity in each case, meaning the results would not be considered significant.
"We also looked at the type of wine - whether drinking red wine or white wine made a difference - and we could not find a significant difference there either," Dr. Li said.
However, when the researchers analyzed the amount of drinking, there was a pattern, she said. When compared with women who had less than one drink a day:
Dr. Li said that when the data were analyzed for type and amount of drink a similar pattern for each type of alcohol was observed - the more drinks of any particular type of alcoholic beverage increased the risk of breast cancer.
"We believe that the culprit is alcohol itself," she said.
Why alcohol should cause breast cancer remains a mystery, said oncologist John Smyth, M.D., of the Edinburgh Cancer Research Center at the University of Edinburgh in Scotland.
"I don't think anyone has a very good idea about what the mechanism of action could be," said Dr. Smyth, president of the Federation of European Cancer Societies, which sponsors the biennial ECCO meeting.
"It appears, like many things in life, that moderation is the best approach with alcohol," he said. "We believe that alcohol has some benefits but when can have detrimental effects when taken to excess."