Information & Support

Factors That Affect Breast Cancer Risk


Some factors affect breast cancer risk a great deal and others by only a small amount.

Some risk factors you can’t change. For example, the most common risk factors for breast cancer are being a woman and getting older.

Other factors you may be able to control. For example, leading a healthy lifestyle may help lower your risk of breast cancer.

Understanding which factors may affect your risk can help you work with your health care provider to address any concerns and develop a breast cancer screening plan that’s right for you.

Risk factors are listed below

  • Age is a risk factor for breast cancer in both women and men. The older a person is, the more likely they are to get breast cancer
  • Both the age when a woman gives birth to her first child and the number of children a woman gives birth to affect her breast cancer risk.
  • Starting menstrual periods at a young age is linked to a small increase in breast cancer risk.
  • Going through menopause at a later age increases the risk of breast cancer.
  • Drinking alcohol increases the risk of breast cancer.
  • Being female is the main risk factor for breast cancer.
  • Current or recent use of birth control pills slightly increases the risk of breast cancer.
  • Being overweight or obese affects the risk of breast cancer differently for premenopausal and postmenopausal women.
  • Women with high bone density have about a 60-80 percent higher risk of breast cancer compared to women with low bone density.
  • Breastfeeding lowers the risk of breast cancer, especially in premenopausal (before menopause) women.
  • A family history of certain types of cancer can increase the risk of breast cancer. This increased risk may be due to genetics, shared lifestyle factors or other family traits.
  • Women who routinely work night shifts for many years have a small increased risk of breast cancer.