Epigenetic Factors to Reduce Breast Cancer Risk – Part 7

Today I am continuing with my 11-part series of articles about the epigenetic factors that reduce breast cancer risk, wherein my primary goal is to empower you with information to help you avoid breast cancer, heal from it, and/or reduce your risk of recurrence.

For more information on my personal reasons for putting this information together, see Part 1 of the series.

This article, Part 7 of the series, shares the nutrients that have the ability to naturally inhibit estrogen production, which is important for those who have estrogen receptor positive breast cancer, the most common type of breast cancer. High levels of estrogen – whether produced in the body or from outside sources (termed xenoestrogens) – are just one of the risk factors for development of breast tumors. Knowing how to reduce these levels using nutrition and/or supplementation is important.

There are a couple of ways of going about this. One is to block an enzyme known as aromatase, key for the production of estrogen in body tissues, including breast cells, thus reducing estrogen in the body. Women with estrogen driven tumors are often prescribed aromatase inhibiting drugs, and they have far more potent estrogen-squelching effects than simple nutrients do, but they often do too good a job. These drugs can induce severe menopausal symptoms and come with a long list of debilitating side effects. Not everyone experiences these side effects, but the majority of women do have at least some problems with them including joint pain, depression, vision disturbances and hot flashes. One of the most-searched pages on my website is one titled 18 Natural Aromatase Inhibitors so I know this is important to people.

There are many other ways that nutrients naturally lower estrogen levels in the body. Some reduce the abundance of estrogen receptors. Some block or alter estrogen signaling between cells. Some decrease estrogen receptor alpha, known to lead to proliferation of breast cells. Some bind to estrogen and carry it out of the body, thus neutralizing the effects of high levels of circulating estrogen. Some nutrients help the body to break down estrogen, while others inhibit the expression of estrogen-related genes. As you can see, there are many ways that nutrients can inhibit excess estrogen.


So let’s get right to it. The nutrients that are capable of inhibiting excess estrogen production in the body include:

Apigenin – found in celery, chamomile tea, chickpeas, grapefruit, onions, oranges, parsley, rice bran, sorghum bran [1]

Beta-Sitosterol – acai, almonds, amaranth, barley, black rice, Brazil nuts, flaxseed, hemp seed, macadamia nuts, oats, pecans, pistachio nuts, pumpkin seeds, quinoa, rice bran, sesame seeds, soybeans, sunflower seeds, walnuts, wheat, wheat bran [2]

Biochanin A – found in alfalfa sprouts, astragalus, cashews, chickpeas, kidney beans, pinto beans, red clover [3]

Caffeic acid – found in adzuki beans, apples, apicots, barley, bee propolis, buckwheat bran, brown rice, chia seeds, chickpeas, coffee, flaxseed, goji/wolfberry, hazelnuts, lentils, oats, quinoa, sorghum bran, soybeans, sunflower seeds, wheat [4]

Conjugated Linoleic Acid – from organic grass fed beef, butter from grass-fed cows raised organically, full fat (preferably raw, organic) dairy products like cream, milk, yogurt or cheese [5]

Ellagic acid – found in acai, amla, apples, black raspberries, blackberries, Brazil nuts, cranberries, pomegranates, pecans, raspberries, strawberries, walnuts [6]

Ellagitannins – found in amla, bilberries, blueberries, black raspberries, Eucalyptus citriodora, pomegranates, strawberries, raspberries, walnuts [7]

Enterolactone, Enterodiol – from flaxseed, oats [8]

Epigallocatechin-3-gallate (EGCG) – found in amla, green tea [9]

Fiber – found in beans, bran, nuts, seeds, whole grains, fruits and vegetables.  A high fiber diet helps remove excess estrogen from the body. [10]

Genistein – found in chickpeas, kidney beans, quinoa, soybeans [11], [12]

Grapeseed Extract – supplement (make sure it comes from organically grown grapes) [13]

Kaempferol – found in amla, Anasazi beans, barley, black beans, black rice, buckwheat bran, chickpeas, chia seeds, flaxseed, ginkgo biloba, green beans, lentils, quinoa, red beans, rice bran [14]

Lignans – found in acai, barley, Brazil nuts, buckwheat bran, cashews, chia seeds, chickpeas, flaxseed, hemp seed, macadamia nuts, oats, pumpkin seeds, red beans, sesame seeds, soybeans, sunflower seeds, walnuts, wheat, wheat bran [15]

Luteolin – found in celery, lemongrass, lentils, oregano, parsley, peppermint, pomegranate, rice bran, rosemary, sorghum bran [16], [17]

Melatonin – found in bananas, barley, black rice, cherries (tart), ginger, oats, walnuts, and melatonin supplements [18], [19], [20]

Naringenin – found in almonds, all citrus fruit, black rice, rice bran, sorghum bran [21]

Oleuropein – found in olives, olive leaf extract, olive oil [22]

Phloridzin – found in apples [23]

Quercetin – found in adzuki beans, amla, Anasazi beans, apples with peels, apricots, asparagus, barley, black beans, black rice, black tea, blackberries, blueberries, broccoli, capers, cauliflower, celery, cherries, chickpeas, chia seeds, cocoa powder (unsweetened), cranberries, dill, eggplant, elderberries, gingko biloba, grapes (red), green beans, green pepper, green tea, honey, kale, lentils, lettuce (esp Romaine), onions, parsley, pears with peels, peppers, quinoa, raspberries, red onions, sage, shallots, spinach, tea (black and green), tomatoes, yellow snap beans [24], [25]

Resveratrol combined with N-acetylcysteine (NAC) – a 2010 study found that the pair minimized the action of estrogen on MCF-10F cells (healthy human breast cells, estrogen receptor-alpha negative). [26]

Secoisolariciresinol diglucoside (SDG) – found in flaxseed, sunflower seeds [27]

Selenium – from amaranth, barley, Brazil nuts, brewer’s yeast, broccoli, brown rice, buckwheat bran, chickpeas, chicken, garlic, kelp, lentils, liver, macadamia nuts, molasses, oats, onions, pecans, pistachio nuts, pumpkin seeds, quinoa, red beans, salmon, seafood, spelt, sunflower seeds, walnuts, wheat, wheat bran, wheat germ [28]

Sesamol – found in sesame seeds and sesame oil [29]

Vitamin B6 – found in chicken and turkey, grass-fed beef, pistachios, tuna, pinto beans, avocado, molasses, sesame seeds, sunflower seeds – helps liver break down estrogen [30]

Vitamin D3 – found in raw milk, salmon, sunshine, tuna, D3 supplementation [31], [32]

Vitamin E – found in amaranth, barley, black rice, Brazil nuts, brown rice, buckwheat bran, cashews, chickpeas, green beans, hemp seed, lentils, macadamia nuts, oats, pecans, pistachios, quinoa, red beans, rice bran, sesame seeds, spelt, walnuts, wheat, wheat bran [33]

Please note that this is not an exhaustive list, there are likely other nutrients that will have an inhibitory effect on estrogen. As I find the research, I will add it here. As much of the research is only preliminary, we often do not know the exact quantities of a nutrient required to exert estrogen lowering effects so my advice is to include as many of these nutrients in your daily/weekly diet as seems practicable!

IMPORTANT NOTE: Please do not attempt to heal cancer using only a few nutrients. Cancer is a complex disease and requires a multi-disciplinary approach to effectively beat it. It is best to work with an oncologist and/or integrative oncologist and/or oncology naturopath and/or functional medicine doctor for the best results.

For more information on other epigenetic factors that reduce breast cancer risk, please see
Part 1 nutrients that can control regulatory genes
Part 2 nutrients that can reduce damage to DNA
Part 3 nutrients that stop rapid proliferation of cells
Part 4 nutrients that ease cancer promoting inflammation
Part 5 nutrients that change malignant cells back into healthy cells
Part 6 nutrients that alter or restore receptors on breast cancer cells

[1] Induction and inhibition of aromatase (CYP19) activity by natural and synthetic flavonoid compounds in H295R human adrenocortical carcinoma cells – https://www.ncbi.nlm.nih.gov/pubmed/15319488
[2] Beta-Sitosterol, Beta-Sitosterol Glucoside, and a Mixture of Beta-Sitosterol and Beta-Sitosterol Glucoside Modulate the Growth of Estrogen- Responsive Breast Cancer Cells In Vitro and in Ovariectomized Athymic Mice – https://www.ncbi.nlm.nih.gov/pubmed/15113961
[3] Dual Effects of Phytoestrogens Result in U-Shaped Dose–Response Curves – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1240943/pdf/ehp0110-000743.pdf
[4] Caffeine and Caffeic Acid Inhibit Growth and Modify Estrogen Receptor and Insulin-like Growth Factor I Receptor Levels in Human Breast Cancer – https://www.ncbi.nlm.nih.gov/pubmed/25691730
[5] Conjugated linoleic acid blocks estrogen signaling in human breast cancer cells – https://www.ncbi.nlm.nih.gov/pubmed/14988466
[6] Berries and Ellagic Acid Prevent Estrogen-Induced Mammary Tumorigenesis by Modulating Enzymes of Estrogen Metabolism – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2896023/
[7] Pomegranate ellagitannin-derived compounds exhibit antiproliferative and antiaromatase activity in breast cancer cells in vitro – https://www.ncbi.nlm.nih.gov/pubmed/20051378
[8] Estrogen-induced angiogenic factors derived from stromal and cancer cells are differently regulated by enterolactone and genistein in human breast cancer in vivo – https://www.ncbi.nlm.nih.gov/pubmed/19924815
[9] The regulation of steroid receptors by epigallocatechin-3-gallate in breast cancer cells – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5447698/
[10] Dietary fiber intake and risk of postmenopausal breast cancer defined by estrogen and progesterone receptor status—A prospective cohort study among Swedish women – https://onlinelibrary.wiley.com/doi/full/10.1002/ijc.23060?_ga=2.173184803.1695834406.1506587025-826077929.1505289352
[11] Phytoestrogens Induce Differential Estrogen Receptor Alpha- or Beta-Mediated
Responses in Transfected Breast Cancer Cells – http://bit.ly/2Hczhu6
[12] Modulation of estrogen receptor-ß isoforms by phytoestrogens in breast cancer cells – https://www.ncbi.nlm.nih.gov/pubmed/16596234
[13] Grape seed extract is an aromatase inhibitor and a suppressor of aromatase expression – https://www.ncbi.nlm.nih.gov/pubmed/16740737
[14] Inhibitory Aromatase Effects of Flavonoids from Ginkgo Biloba Extracts on Estrogen Biosynthesis – https://www.ncbi.nlm.nih.gov/pubmed/26434836
[15] Inhibition of human aromatase by mammalian lignans and isoflavonoid phytoestrogens – http://www.ncbi.nlm.nih.gov/pubmed/8382517
[16] Inhibitory effect of luteolin on estrogen biosynthesis in human ovarian granulosa cells by suppression of aromatase (CYP19) – https://www.ncbi.nlm.nih.gov/pubmed/22838964
[17] Coadministrating luteolin minimizes the side effects of the aromatase inhibitor letrozole – https://www.ncbi.nlm.nih.gov/pubmed/25138022
[18] Selective estrogen enzyme modulator actions of melatonin in human breast cancer cells – https://www.ncbi.nlm.nih.gov/pubmed/18298468/
[19] Melatonin as a selective estrogen enzyme modulator – https://www.ncbi.nlm.nih.gov/pubmed/19075592
[20] Estrogen-signaling pathway: a link between breast cancer and melatonin oncostatic actions – https://www.ncbi.nlm.nih.gov/pubmed/16647824/
[21] Naringenin: a partial agonist on estrogen receptor in T47D-KBluc breast cancer cells – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3832325/
[22] Combining computational and biochemical studies for a rationale on the anti-aromatase activity of natural polyphenols – https://www.ncbi.nlm.nih.gov/pubmed/17910019
[23] Estrogenic and antiestrogenic activities of phloridzin – https://www.ncbi.nlm.nih.gov/pubmed/20410591
[24] Inhibitory Aromatase Effects of Flavonoids from Ginkgo Biloba Extracts on Estrogen Biosynthesis – https://www.ncbi.nlm.nih.gov/pubmed/26434836
[25] Quercetin-induced apoptotic cascade in cancer cells: antioxidant versus estrogen receptor alpha-dependent mechanisms – https://www.ncbi.nlm.nih.gov/pubmed/19194971
[26] Resveratrol and N-acetylcysteine block the cancer-initiating step in MCF-10F cells – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4425208/
[27] Effects of flaxseed lignan secoisolariciresinol diglucoside on preneoplastic biomarkers of cancer progression in a model of simultaneous breast and ovarian cancer development – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5025029
[28] Methylseleninic acid is a novel suppressor of aromatase expression – https://www.ncbi.nlm.nih.gov/pubmed/22128327
[29] Estrogenic activities of sesame lignans and their metabolites on human breast cancer cells – https://www.ncbi.nlm.nih.gov/pubmed/21141889
[30] The interactions between vitamin B6 and hormones – https://www.ncbi.nlm.nih.gov/pubmed/217175
[31] 1,25-dihydroxyvitamin D3 downregulates aromatase expression and inflammatory cytokines in human macrophages – https://www.ncbi.nlm.nih.gov/pubmed/23253631
[32] The Potential Therapeutic Benefits of Vitamin D in the Treatment of Estrogen Receptor Positive Breast Cancer – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3429709/
[33] Inhibitory Effects of Gamma- and Delta-Tocopherols on Estrogen-Stimulated Breast Cancer in Vitro and in Vivo – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5337152/

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