Light Drinking Over Time May Raise Breast Cancer Risk
Routinely Drinking as Little as Three Drinks a Week Can Raise Breast Cancer Risk, Study Finds
Is Lifestyle Impact Overstated?
Narod is chairman of breast cancer research at the Women’s College Research Institute in Toronto.
"If alcohol increases risk, it does not come down to how much a woman drank over the last year but how much she drank over the last 20 years," he tells WebMD.
Because most of the breast cancers in the study population occurred in postmenopausal women, Narod says the findings do not really address the role of alcohol use on breast cancers in younger women.
"We know precious little about the role of lifestyle, if any, on the development of breast cancers in premenopausal women," he says.
Avoiding alcohol, maintaining a healthy weight, and exercising have all been linked to a reduction in breast cancer risk in older women.
But Narod believes the importance of these lifestyle factors on breast cancer has been overstated.
"If every woman stopped drinking and every woman who was overweight lost weight, the risk of postmenopausal breast cancer might be reduced by 10%, but that isn’t going to happen," he says.
Chen concedes that the impact of lifestyle on breast cancers at the population level may be modest, but she says the impact for an individual woman may be huge.
“It is true that we won’t prevent all breast cancers by changing lifestyle, but we will prevent some,” she says