It isn’t the type of alcohol but the quantity which increases a woman’s risk of contracting breast cancer.
In fact, the increased breast cancer risk from drinking three or more alcoholic drinks a day is similar to the increased breast cancer risk from smoking a pack of cigarettes or more a day, according to Kaiser Permanente researchers Yan Li, MD, PhD and Arthur Klatsky, MD.
"Population studies have consistently linked drinking alcohol to an increased risk of female breast cancer, but until now there has been little data, most of it conflicting, about an independent role played by the choice of beverage type," said Klatsky, who is presentied these findings on Sept. 27 at the European Cancer Conference (ECCO 14) in Barcelona, Spain.
The study found there was no difference between wine, beer or spirits in the risk of developing breast cancer. Even when wine was divided into red and white, there was no difference. However, when researchers looked at the relationship between breast cancer risk and total alcohol intake, they found that women who drank between one and two alcoholic drinks per day increased their risk of breast cancer by 10 percent compared with light drinkers who drank less than one drink a day. The risk of breast cancer increased by 30 percent in women who drank more than three drinks a day.
"A 30 percent increased risk is not trivial. To put it into context, it is not much different from the increased risk associated with women taking estrogenic hormones. Incidentally, in previous research completed at Kaiser Permanente, we have found that smoking a pack of cigarettes or more per day is related to a similar (30 percent) increased risk of breast cancer," Klatsky said.
Although breast cancer incidence varies between populations and only a small proportion of women are heavy drinkers, Dr Klatsky said that a 30 percent increase in the relative risk of breast cancer from heavy drinking might translate into approximately an extra 5 percent of all women developing breast cancer as a result of their habit.
"Klatsky said that all medical advice needed to be personalized to the individual. "Our findings provide more evidence for why heavy drinkers should quit or cut down."