Up to 10 percent of breast cancer cases are caused by mutations in tumor suppressor genes, including breast cancer susceptibility gene-1 (BRCA1) and breast cancer susceptibility gene-2 (BRCA2). Proteins made by these genes are used to repair damaged DNA. Defects in this process cause mutation carriers to have high lifetime risks of developing breast, ovarian and some other cancers.
One study foud that BRCA1 carriers in Poland had far lower rates of breast cancer than BRCA1 carriers in North America, indicating that the increased risks associated with BRCA mutations might be modified by lifestyle factors.
Medium intensity physical activity has been found to be associated with a modest reduction in breast cancer risk for BRCA1 and BRCA2 carriers. In addition, there are some foods that have been found to protect against breast cancer in BRCA1 and/or BRCA2 carriers. BRCA1 and BRCA2 carriers diagnosed with breast cancer can also refer to our articles concerning their breast cancer subtypes (e.g. triple negative, ER+/PR+) for additional advice on what to eat.
Foods that reduce risk of breast cancer in BRCA1 and BRCA2 carriers
The following foods have been found to be associated with reduced risk of breast cancer in BRCA1 and/or BRCA2 carriers or are rich sources of compounds that have been found to influence BRCA1 and/or BRCA2 expression in a favorable way:
- Arctic char
- Black pepper
- Brazil nuts
- Brussels sprouts
- Collard greens
- Flaxseed oil
- Grapes, red
- Green tea
- Honey, min. processed
Several studies have found that heavy coffee consumption is associated with significantly reduced breast cancer risk among women with BRCA1 or BRCA2 gene mutations. However, a 2013 study reported that increased breast cancer risk was found for BRCA1 mutation carriers who were heavy coffee drinkers.
Beneficial supplements for BRCA mutation carriers
There is no supplement or combination of supplements that has been shown conclusively to reduce the risk of breast cancer recurrence. Attempting to take advantage of the apparent treatment effects of micronutrients and other dietary components by using supplements carries the risk of adverse and paradoxical effects, including promoting breast cancer growth and metastasis.
What is known is that when a beneficial micronutrient is administered at low doses by consuming food, it is likely to have subtle chemopreventive effects, whereas when the same micronutrient is administered at high doses, it is more likely to have pharmacological effects, with mostly unknown results. It is best to obtain beneficial compounds by consuming food, if possible. The role of supplements is to make up for deficiencies that are difficult to correct through diet.
The following supplements generally have been found to be safe and beneficial for carriers of harmful BRCA mutations:
Avoid taking supplements during the two days before, the day of, and the day after any chemotherapy treatment. Please consult your oncology team for advice concerning your situation and dosages.
There is some specific evidence that maintaining optimal levels of vitamin D could reduce the risk of triple negative breast cancer among BRCA1 carriers. It might make sense to be tested for deficiency in vitamin D and plan for follow up to determine if your reading has reached a desirable level.
Young women in general and BRCA1 mutation carriers in particular should avoid iron deficiency, since it has been linked to higher risk of breast cancer in these populations. However, one Korean study suggested that meat consumption preferentially increased breast cancer risk in BRCA2 carriers.
Foods to limit or avoid for BRCA mutation carriers
One study reported that consumption of flame-broiled fish was associated with increased risk of breast cancer in BRCA mutation carriers through its heterocyclic amine (HCA) content. Another 2020 study reported that consuming reheated cooking oil intensifies harmful BRCA1 mutations, apparently since repeated heating of oils produces reactive toxic intermediates that can lead to such mutations. This suggests that restaurant foods such as French fries that are cooked in oil that is used for many hours over a period of days should be avoided.
The relationship between alcohol and breast cancer risk in BRCA mutation carriers is unclear because not all studies have reported a harmful effect of alcohol consumption. However, one compelling 2015 study reported that embryos with BRCA1 deficiencies were particularly susceptible to the carcinogenic effects of alcohol in an animal model of breast cancer. Smoking during the pre-reproductive years appears to increase breast cancer risk for harmful BRCA mutation carriers.
Supplements to be avoided by BRCA mutation carriers
While supplements containing I3C, DIM, resveratrol, and genistein (all protective against BRCA-associated breast cancer) are readily available, the safer and healthier strategy is to consume foods that contain these substances. Safe and effective dosages have not been determined for these compounds.
A 2016 study reported that high circulating levels of folate was associated with increased risk of breast cancer in BRCA 1 and BRCA 2 mutation carriers, suggesting that folic acid supplements could be harmful. On the other hand, a 2019 study reported that folic acid and/or vitamin B12 supplement use was associated with reduced risk of breast cancer for BRCA 1 carriers.
Foods that reduce risk of ovarian cancer
The following foods have been found to be associated with lower risks of both ovarian cancer and breast cancer:
Foods that increase risk of ovarian cancer
The following foods have been found to increase the risks of both ovarian cancer and breast cancer:
- Bread, baguettes & croissants, white
- Cookies, candy and cake
- Cured and salted meats
- Fish contaminated with PCBs
- Milk, including low-fat
- Plantains, fried ripe
Bisphenol A (BPA) exposure
Bisphenol A (BPA), an endocrine disruptor, is suspected of increasing the risk of breast cancer. BPA has been found to stimulate mammary cell proliferation in BRCA1 mutant mice, leading to hyperplasia. This suggests that women with BRCA1 mutations might be particularly vulnerable to the cancer promoting effects of BPA. BPA exposure can be limited by avoiding canned foods, canned sodas, and polycarbonate plastic bottles and food containers, which may be marked with a 7 or 3 recycling number in a triangle-shaped icon (normally found on the base).
Antiperspirants containing aluminum compounds
Most antiperspirant sprays, sticks, and roll-ons contain aluminum chlorohydrate or other aluminum salts designed to block the secretion of sweat. The aluminum in such preparations has been shown to enter through the skin in tiny amounts and to accumulate in breast tissue. Applying an antiperspirant to skin that is scraped, cut or irritated (such as may occur after shaving) can result in significantly higher exposures. Aluminum has been demonstrated to cause DNA damage and to induce inflammatory responses within the breast. Aluminum salts found in antiperspirants were also shown in one study to reduce level of BRCA1 mRNA and BRCA1 protein in normal breast epithelial cells. Levels of BRCA2 and other tumor suppressor genes (CHK1, CHK2, Rad51, and ATR) were also reduced. Given that aluminum appears to interfere with the functioning of tumor suppressor genes, BRCA mutation carriers should probably entirely avoid using aluminum-containing antiperspirants and deodorants.
Eat a wide variety of foods
It is important for BRCA1 and BRCA2 mutation carriers to eat a wide variety of the foods from our recommended food list and limit or avoid those on our avoid list, in addition to paying particular attention to the foods on the lists above. Please see our article on how to optimize your breast cancer diet for information on what to eat during all stages of treatment and recovery.
Below are links to recent studies on this topic. For a more complete list of studies, please click on BRCA1 and BRCA2.
Selected breast cancer studies
Circulating carotenoids and breast cancer among high-risk individuals
Peng C, Gao C, Lu D, Rosner BA, Zeleznik O, Hankinson SE, et al. Circulating carotenoids and breast cancer among high-risk individuals. The American Journal of Clinical Nutrition. Oxford University Press (OUP); 2020; 10.1093/ajcn/nqaa316
Sugar-containing beverages and their association with risk of breast, endometrial, ovarian and colorectal cancers among Canadian women
Arthur RS, Kirsh VA, Mossavar-Rahmani Y, Xue X, Rohan TE. Sugar-containing beverages and their association with risk of breast, endometrial, ovarian and colorectal cancers among Canadian women. Cancer Epidemiology. Elsevier BV; 2020; 70:101855 10.1016/j.canep.2020.101855
Consumption of reused vegetable oil intensifies BRCA1 mutations
Rajendran P, Alzahrani AM, Rengarajan T, Veeraraghavan VP, Krishna Mohan S. Consumption of reused vegetable oil intensifies BRCA1 mutations. Critical Reviews in Food Science and Nutrition. Informa UK Limited; 2020;:1-8 10.1080/10408398.2020.1837725
Protective Effects of Epigallocatechin Gallate (EGCG) on Endometrial, Breast, and Ovarian Cancers
Huang Y, Wang K, Chen H, Chiang Y, Hsia S. Protective Effects of Epigallocatechin Gallate (EGCG) on Endometrial, Breast, and Ovarian Cancers. Biomolecules. MDPI AG; 2020; 10:1481 10.3390/biom10111481
Isoflavone intake on the risk of overall breast cancer and molecular subtypes in women at high risk for hereditary breast cancer
Sim EJ, Ko K, Ahn C, Park SM, Surh Y, An S, et al. Isoflavone intake on the risk of overall breast cancer and molecular subtypes in women at high risk for hereditary breast cancer. Breast Cancer Research and Treatment. Springer Science and Business Media LLC; 2020; 184:615-626 10.1007/s10549-020-05875-0
3,3-Diindolylmethane (DIM): a nutritional intervention and its impact on breast density in healthy BRCA carriers. A prospective clinical trial
Yerushalmi R, Bargil S, Ber Y, Ozlavo R, Sivan T, Rapson Y, et al. 3,3-Diindolylmethane (DIM): a nutritional intervention and its impact on breast density in healthy BRCA carriers. A prospective clinical trial. Carcinogenesis. Oxford University Press (OUP); 2020; 41:1395-1401 10.1093/carcin/bgaa050
Curcumin induces re‑expression of BRCA1 and suppression of γ synuclein by modulating DNA promoter methylation in breast cancer cell lines
Al‑Yousef N, Shinwari Z, Al‑Shahrani B, Al‑Showimi M, Al‑Moghrabi N. Curcumin induces re‑expression of BRCA1 and suppression of γ synuclein by modulating DNA promoter methylation in breast cancer cell lines. Oncology Reports. Spandidos Publications; 2020; 10.3892/or.2020.7473
Alcohol Consumption, Cigarette Smoking, and Risk of Breast Cancer for BRCA1 and BRCA2 Mutation Carriers: Results from The BRCA1 and BRCA2 Cohort Consortium
Li H, Terry MB, Antoniou AC, Phillips K, Kast K, Mooij TM, et al. Alcohol Consumption, Cigarette Smoking, and Risk of Breast Cancer for BRCA1 and BRCA2 Mutation Carriers: Results from The BRCA1 and BRCA2 Cohort Consortium. Cancer Epidemiology Biomarkers & Prevention. American Association for Cancer Research (AACR); 2019; 29:368-378 10.1158/1055-9965.epi-19-0546
Curcumin induces DNA damage by mediating homologous recombination mechanism in triple negative breast cancer
Guney Eskiler G, Sahin E, Deveci Ozkan A, Cilingir Kaya OT, Kaleli S. Curcumin induces DNA damage by mediating homologous recombination mechanism in triple negative breast cancer. Nutrition and Cancer. Informa UK Limited; 2019; 72:1057-1066 10.1080/01635581.2019.1670216
Prediagnosis aspirin use, DNA methylation, and mortality after breast cancer: A population‐based study
Wang T, McCullough LE, White AJ, Bradshaw PT, Xu X, Cho YH, et al. Prediagnosis aspirin use, DNA methylation, and mortality after breast cancer: A population‐based study. Cancer. Wiley; 2019; 125:3836-3844 10.1002/cncr.32364
MON-038 The Effects of Isoliquiritigenin (ISL) on the Expression of Estrogen Receptor and Tumor Suppressor Genes BRCA-1 and P53 in Breast Cancer Cells
Crone M, Lloyd V, Szmyd M, Morse M, Badamo B, Parker J, et al. MON-038 The Effects of Isoliquiritigenin (ISL) on the Expression of Estrogen Receptor and Tumor Suppressor Genes BRCA-1 and P53 in Breast Cancer Cells. Journal of the Endocrine Society. The Endocrine Society; 2019; 3 10.1210/js.2019-mon-038
The Effect of Green and Black Tea Polyphenols on BRCA2 Deficient Chinese Hamster Cells by Synthetic Lethality through PARP Inhibition
Alqahtani S, Welton K, Gius J, Elmegerhi S, Kato T. The Effect of Green and Black Tea Polyphenols on BRCA2 Deficient Chinese Hamster Cells by Synthetic Lethality through PARP Inhibition. International Journal of Molecular Sciences. MDPI AG; 2019; 20:1274 10.3390/ijms20061274
The antiestrogenic effects of black cohosh on BRCA1 and steroid receptors in breast cancer cells
Crone M, Hallman K, Lloyd V, Szmyd M, Badamo B, Morse M, et al. The antiestrogenic effects of black cohosh on BRCA1 and steroid receptors in breast cancer cells. Breast Cancer: Targets and Therapy. Informa UK Limited; 2019; Volume 11:99-110 10.2147/bctt.s181730
A Dietary Intervention to Lower Serum Levels of IGF-I in BRCA Mutation Carriers
Pasanisi P, Bruno E, Venturelli E, Morelli D, Oliverio A, Baldassari I, et al. A Dietary Intervention to Lower Serum Levels of IGF-I in BRCA Mutation Carriers. Cancers. MDPI AG; 2018; 10:309 10.3390/cancers10090309
Abstract 248: Association of vitamin D related polymorphisms with hereditary breast cancer in 431 patients wild type forBRCA1andBRCA2mutations
Aristarco V, Serrano D, Barile M, Bondavalli D, Calvello M, Macis D, et al. Abstract 248: Association of vitamin D related polymorphisms with hereditary breast cancer in 431 patients wild type forBRCA1andBRCA2mutations. Epidemiology. American Association for Cancer Research; 2018; 10.1158/1538-7445.am2018-248
Adherence to Mediterranean Diet and Metabolic Syndrome in BRCA Mutation Carriers
Bruno E, Manoukian S, Venturelli E, Oliverio A, Rovera F, Iula G, et al. Adherence to Mediterranean Diet and Metabolic Syndrome in BRCA Mutation Carriers. Integrative Cancer Therapies. SAGE Publications; 2017; 17:153-160 10.1177/1534735417721015
Aldehydes Pose a Threat to BRCA2 Mutation Carriers
Parmar K, D’Andrea AD. Aldehydes Pose a Threat to BRCA2 Mutation Carriers. Cell. Elsevier BV; 2017; 169:979-981 10.1016/j.cell.2017.05.021
Effects of lifestyle and diet as modifiers of risk of breast cancer (BC) in BRCA1 and BRCA2 carriers.
Pollan M, Torres A, Ramon Y Cajal T, Llort G, Castello A, Fisas D, et al. Effects of lifestyle and diet as modifiers of risk of breast cancer (BC) in BRCA1 and BRCA2 carriers.. Journal of Clinical Oncology. American Society of Clinical Oncology (ASCO); 2017; 35:1505-1505 10.1200/jco.2017.35.15_suppl.1505
Plasma folate, vitamin B-6, and vitamin B-12 and breast cancer risk in BRCA1- and BRCA2-mutation carriers: a prospective study
Kim SJ, Zuchniak A, Sohn K, Lubinski J, Demsky R, Eisen A, et al. Plasma folate, vitamin B-6, and vitamin B-12 and breast cancer risk in BRCA1- and BRCA2-mutation carriers: a prospective study. The American Journal of Clinical Nutrition. Oxford University Press (OUP); 2016; 104:671-677 10.3945/ajcn.116.133470