Women who menstruated earlier than average, who had no children or a late first pregnancy, or who entered menopause late are at higher-than average risk. So are women whose mother or sister had breast cancer. Control your weight and cut back on the amount of fat in your diet.
Many studies suggest that a high-fat diet and being overweight increase the risk of breast cancer.
Limit your alcohol intake. Some research has shown that women who have three or more drinks a week increase their risk of breast cancer.