For years, many women have believed that family history is the biggest predictor of breast cancer. While genetics do play a role in breast cancer, new research in epigenetics reveals something far more empowering: our lifestyle choices can actually influence how those genes are expressed. 

Epigenetics is the science of how factors like diet, stress, sleep, and environment can “switch on” or “switch off” the activity of certain genes. This means that even if you carry genetic risk factors, you still hold remarkable power to change the trajectory of your health by making good lifestyle choices. 

From a nutritionist’s perspective, this is one of the most inspiring messages to share with women. Food doesn’t just fuel your body—it actively interacts with your DNA, influencing pathways related to cell growth, repair, and inflammation. Here are some examples of foods and micronutrients that promote breast health: 

• Cruciferous vegetables like broccoli, kale, and Brussels sprouts contain antioxidant compounds (sulforaphane, indole-3-carbinol) that, when converted to DIM (diindolylmethane), are shown to promote protective detoxification pathways and regulate estrogen metabolism.

• Mushrooms are rich in antioxidant compounds such as ergothioneine and 1,3 beta glucan. In fact, a systematic review and meta-analysis examining 17 cancer studies between 1966 and 2020 found that individuals who consumed an average of 1/8 to 1 / 4 cup of mushrooms daily had a 45% lower risk of cancer (all types) and a significantly lower risk of breast cancer, compared to those who did not eat mushrooms. 

• Polyphenols are antioxidants found in berries, grapes, green tea, and curcumin that have been studied for their ability to repair DNA damage and support balanced cell growth. This may be especially important for women after menopause, since about 2 out of 3 breast cancer cases are diagnosed at age 55 or older. Research suggests that certain polyphenols, particularly phenolic acids and lignans, may offer protective benefits in post-menopausal women.

Even younger women can glean breast benefits from fruits and vegetables, specifically from berries, grapes (both rich in polyphenols), apples, oranges and kale (a cruciferous vegetable) during adolescence or early adulthood, says a study published in the British Medical Journal in 2016.  This study saw intake of these foods was significantly associated with reduced risk of breast cancer. 

Immune Nutrients for Stronger Breast Defense

Maintaining the efficiency of your immune system is a key part of breast health.  A healthy immune system works like a security team, always on the lookout for cells that don’t belong in your body. The right nutrients help keep this team strong and alert: 

• Zinc helps the immune “patrol cells” called T cells and natural killer (NK) cells do their job of spotting and removing abnormal cells. It also supports DNA repair so everyday cell ‘mistakes’ don’t build up over time.

• Selenium acts as part of the body’s natural antioxidant shield, protecting cells from damage. It also encourages old or unhealthy cells to step aside so new, healthy ones can take their place.

• Vitamin C neutralizes harmful free radicals before they can damage DNA and boosts the activity of white blood cells so your immune system stays sharp.

• Vitamin D helps your immune system recognize when something’s “off” and keeps hormones in better balance. Breast tissue is one of many tissues that has vitamin D receptors, which means it directly influences how cells grow and renew themselves.

Together, these nutrients act like every-day guardians — keeping your immune defenses strong, protecting breast cells from stress, and supporting healthy renewal.

This doesn’t mean that nutrition should replace breast screening or medical care. But it does mean that every meal, every supplement, every lifestyle choice is an opportunity to influence gene expression in your favour. 

The future of breast health isn’t just about genetics—it’s about epigenetics. Women can shift from feeling powerless about family history to feeling empowered about good daily habits in the areas of nourishment, activity, and rest. Your genes may set the stage, but the lifestyle choices you make determine the performance. Epigenetics gives us the science to back up what nutritionists have always known: nutrients are powerful allies for your health. 

References 

Abdal Dayem A, Choi HY, Yang GM, Kim K, Saha SK, Cho SG. The Anti-Cancer Effect of Polyphenols against Breast Cancer and Cancer Stem Cells: Molecular Mechanisms. Nutrients. 2016;8(9):581. Published 2016 Sep 21. 

Ba DM, Ssentongo P, Beelman RB, Muscat J, Gao X, Richie JP. Higher Mushroom Consumption Is Associated with Lower Risk of Cancer: A Systematic Review and Meta-Analysis of Observational Studies. Adv Nutr. 2021;12(5):1691-1704. 

Farvid MS, Chen WY, Michels KB, Cho E, Willett WC, Eliassen AH. Fruit and vegetable consumption in adolescence and early adulthood and risk of breast cancer: population based cohort study. BMJ. 2016;353:i2343. Published 2016 May 11. 

Gardeazabal I, Romanos-Nanclares A, Martínez-González MÁ, et al. Total polyphenol intake and breast cancer risk in the Seguimiento Universidad de Navarra (SUN) cohort. Br J Nutr. 2019;122(5):542-551. 

Garland CF, Gorham ED, Mohr SB, et al. Vitamin D and prevention of breast cancer: pooled analysis. [Abstract only]. J Steroid Biochem Mol Biol. 2007;103(3-5):708-711. 

Higdon JV, Delage B, Williams DE, Dashwood RH. Cruciferous vegetables and human cancer risk: epidemiologic evidence and mechanistic basis. Pharmacol Res. 2007;55(3):224-236. 

Kim A, Mo K, Kwon H, et al. Epigenetic Regulation in Breast Cancer: Insights on Epidrugs. Epigenomes. 2023;7(1):6. Published 2023 Feb 18. 

National Institutes of Health, Office of Dietary Supplements. Dietary Supplements for Immune Function and Infectious Diseases: Fact Sheet for Health Professionals. 

Rudolph A, Chang-Claude J, Schmidt MK. Gene-environment interaction and risk of breast cancer. Br J Cancer. 2016;114(2):125-133.