Approximately 1 in 8 women in the US will develop breast cancer in their lifetime. Breast cancer is the most common, invasive cancer among women worldwide, as well as in the United States. The Internet is filled with confusing and conflicting messages about various lifestyle factors that can impact breast cancer risk, which makes it difficult to know which claims are actually supported by scientific evidence. Many are often left wondering, “How can I reduce my breast cancer risk?” After analyzing decades of evidence from millions of cancer cases globally, the experts at American Institute for Cancer Research (AICR) have summarized key findings on breast cancer risk factors and recommendations on how to lower the risk.

Evidence on Breast Cancer Risk

Alcohol: Drinking alcohol increases the risk for breast cancer.

Weight: Having excess body fat increases the risk for post-menopausal breast cancer.

Physical activity: Sedentary behavior is linked to increased risk of cancer, while being active decreases the risk for breast cancer.

  • Vigorous activity decreases the risk for pre-menopausal breast cancer.
  • Moderate activity decreases risk for post-menopausal breast cancer.
  • Some evidence indicates that people who are physically active (both before and after diagnosis) have a greater chance of surviving breast cancer.

Breastfeeding: Breastfeeding lowers the risk for breast cancer.

  • Breastfeeding lowers the levels of some cancer-related hormones in mother’s body.
  • At the end of the breastfeeding phase, the body gets rid of any cells in the breast that may have DNA damage.

Science shows that living a cancer-protective lifestyle – by making lifestyle decisions such as avoiding alcohol, being a healthy weight, being physically active, eating a diet rich in whole grains, vegetables, fruits and beans can reduce the risk for cancer.

Why AICR Recommendations

Dr. Nigel Brockton, Vice President of Research at AICR, summarizes the evidence-based recommendations to reduce breast cancer risk and explains how following these recommendations are steps in the right direction. Watch:


Take AICR’s Cancer Health Check to see how your lifestyle choices rank against the 10 Cancer Prevention Recommendations, and how you can take small steps to stack odds in your favor.

Additional Resources

The Continuous Update Project (CUP) is an ongoing program that analyzes global research on how diet, nutrition and physical activity affect cancer risk and survival. Developed in collaboration with the World Cancer Research Fund International, the Report is widely regarded as a trusted and authoritative scientific resource. Here are the latest CUP Reports on breast cancer:

This article was originally published on October 1, 2020, by American Institute for Cancer Research. It is republished with permission.