Everyone has some risk of developing breast cancer. In the United States, 1 in 8 women will be diagnosed with invasive breast cancer over the course of her lifetime. This means the average woman’s breast cancer risk is 12-13%. A man’s lifetime risk is much lower, 1 in 833.
Being a woman and aging are the two biggest risk factors, but there are many other things that can increase or decrease a person’s breast cancer risk.
Understanding your own personal risk factors can help empower you to take action to keep your breast cancer risk as low as possible.
Breast cancer risk factors
Some of the factors associated with breast cancer risk can’t be changed, such as age and genetics. Other factors, such as lack of exercise, smoking, and eating unhealthy food can be changed by choosing healthier lifestyle options. Learn more about breast cancer risk factors and steps you can take to help protect your breast health.
- Being a Woman
- Family History
- Personal History of Breast Cancer
- Prior Radiation to Chest or Face
- Certain Breast Changes
- Being Overweight
- Pregnancy History
- Breastfeeding History
- Menstrual History
- Using HRT (Hormone Replacement History)
- Drinking Alcohol
- Dense Breasts
- Lack of Exercise
- Low Vitamin D Levels
- Light Exposure at Night
- DES (Diethylstilbestrol) Exposure
- Eating Unhealthy Food
- Exposure to Chemicals in Cosmetics
- Exposure to Chemicals in Food
- Exposure to Chemicals for Lawns and Gardens
- Exposure to Chemicals in Plastic
- Exposure to Chemicals in Sunscreen
- Exposure to Chemicals in Water
- Exposure to Chemicals When Food Is Grilled/Prepared
Common Fears With No Evidence: Antiperspirants and Bras
Occasionally, media stories or posts on social media will claim that antiperspirants and bras increase breast cancer risk. There is no scientific evidence to support either of these rumors. Learn more.
Understanding breast cancer risk
Researchers are working to understand how different factors work separately and together to affect your health and your risk of developing breast cancer. By making healthier choices — such as quitting smoking or eating nutritious foods — you can help keep your risk as low as it can be. Learn about what risk means and how that risk can change.
- Your Risk of Breast Cancer
- Absolute vs. Relative Risk: What Does Percentage Risk Really Mean?
- Examples of Risk Increasing and Decreasing
This content was developed with contribution from the following experts:
Marisa Weiss, M.D., director of breast radiation oncology and director of breast health outreach, Lankenau Hospital, Main Line Health, Philadelphia area, PA; Breastcancer.org founder and chief medical officer
Joan Ruderman, Ph.D., Nelson Professor of cell biology, Harvard Medical School, Boston, MA and member of the National Academy of Sciences
Carmi Orenstein, MPH, translational researcher
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