That's the suggestion of researchers who found that cancer is 34% more likely to come back in breast cancer survivors who drink more than three drinks a week, compared with those who abstain or drink less.
Drinking more than three drinks a week also raised the risk of dying from breast cancer by 51%, says Marilyn L. Kwan, PhD, a staff scientist at Kaiser Permanente in Oakland, Calif.
"Women with breast cancer who are postmenopausal or overweight seem to be most susceptible to the effects of alcohol," she tells WebMD.
So Kwan and colleagues followed 1,897 women who had been successfully treated for early-stage breast cancer between 1997 and 2000. About a year after diagnosis, they were asked whether they drank alcohol, how much they drank, and their drink of choice.
Over the next eight years, 349 of the women suffered a recurrence of their breast cancer, and 332 died of the disease.
"We don't think the type of alcohol mattered, but it was difficult to examine since 90% of the women in our study drank wine," Kwan says. But how much they drank did matter; women who indulged in two or more glasses of wine per day were most likely to suffer a recurrence, she says.
It makes sense that alcohol would raise both the risk of developing breast cancer and the chance that it will come back, Kwan says. "Alcohol increases levels of estrogen in the body, and breast cancer is fueled by estrogen."
Jeffrey Peppercorn, MD, a breast cancer specialist at Duke University, tells WebMD that women who are diagnosed with breast cancer often want to know what they can do to lower their risk of recurrence.
"Limiting alcohol consumption is one step they can take," he says. "I tell women we're not sure that any amount of alcohol is safe ... but that it would be prudent to limit consumption except on rare, special occasions."