Women who drink are more likely to have breast cancer. Drinking 1 to 7 drinks a week raises the risk of developing breast cancer in the milk-producing lobules of the breast. For women who drink 14 alcoholic beverages a week the risk of lobular cancer was twice that of nondrinkers. Only 10% to 15% of all breast cancers are lobular.
Alcohol did not increase the risk of breast cancer in the milk ducts which accounts for 70% of all breast cancer.