Prevention

There are things you can do to help lower your risk of breast cancer, including some lifestyle choices. Learn more to inform your decisions around risk factors that are more within your control.

Lifestyle Choices and Breast Cancer Risk

• Alcohol use: Use of alcohol has been linked to an increased risk of getting breast cancer. Women who have one drink a day have a very small increased risk. Those who have 2 to 5 drinks daily have about 1½ times the risk of women who drink no alcohol. The American Cancer Society suggests limiting the amount you drink to one drink a day.
• Being overweight or obese: Being overweight or obese is linked to a higher risk of breast cancer, especially for women after menopause and if the weight gain took place during adulthood. Also, the risk seems to be higher if the extra fat is in the waist area. But the link between weight and breast cancer risk is complex, and studies of fat in the diet as it relates to breast cancer risk have often given conflicting results. The American Cancer Society recommends you maintain a consistently healthy weight throughout your life without periods of excess weight gain.
• Lack of exercise: Studies show that exercise reduces breast cancer risk, but exactly how much exercise is needed is undetermined. One study found that as little as 1 hour and 15 minutes to 2½ hours of brisk walking per week reduced the risk by 18%. Walking 10 hours a week reduced the risk a little more. The American Cancer Society suggests exercising 45 to 60 minutes, 5 or more days a week.
• Not having children or having them later in life: Women who have had not had children, or who had their first child after age 30, have a slightly higher risk of breast cancer. Being pregnant more than once and at an earlier age reduces breast cancer risk. The reason may be because pregnancy reduces a woman's total number of lifetime menstrual cycles.
• Recent use of birth control pills: Studies have found that women who are using birth control pills have a slightly greater risk of breast cancer than women who have never used them. Women who stopped using the pill more than 10 years ago do not seem to have any increased risk. Get more information specific to you from your doctor about the risks and benefits of birth control pills.
• Postmenopausal hormone therapy (PHT): Postmenopausal hormone therapy (also known as hormone replacement therapy), has been used for many years to help relieve symptoms of menopause and to help prevent thinning of the bones, or osteoporosis. There are two main types of PHT:
  • For women who have a uterus, doctors generally prescribe estrogen and progesterone, known as combined PHT. Estrogen alone can increase the risk of cancer of the uterus, so progesterone is added to help prevent this.
  • For women who no longer have a uterus (those who've had a hysterectomy), estrogen alone can be prescribed. This is commonly known as estrogen replacement therapy (ERT).
• Combined PHT: It has become clear that use for several years or more of combined PHT increases the risk of breast cancer and may increase the chances of dying of breast cancer. Breast cancer may also be discovered at an advanced stage, perhaps because PHT seems to reduce the effectiveness of mammograms. Five years after stopping PHT, the breast cancer risk has been shown to drop back to normal.
• ERT: The use of estrogen alone does not seem to increase the risk of developing breast cancer much, if at all. But when used for more than 10 years, some studies have found that ERT increases the risk of ovarian and breast cancer.
• Not breast-feeding: Some studies have shown that breast-feeding slightly lowers breast cancer risk, especially if the breast-feeding lasts 1½ to 2 years. This could be because breast-feeding lowers a woman's total number of menstrual periods, as does pregnancy.