18 Natural Aromatase Inhibitors
The number one topic in breast cancer communities, and the thing I get asked about most often, is about natural aromatase inhibitors. People are suffering from the effects of hormone inhibiting drugs – the list of side effects these drugs are capable of producing is seemingly endless. As a breast cancer coach, I hear all about them and have a great deal of sympathy for those taking these drugs.
It’s a subject near and dear to our hearts and we can spend plenty of time trying to dig up research on new natural alternatives – I know I do because I chose not to take Tamoxifen, much to my oncologist’s annoyance. I just wasn’t willing to risk the side effects, such as cardiotoxicity and blood clots, etc.
Update: I recently wrote an article sharing why I chose not to take Tamoxifen, in case you’re interested: Why I Chose Against Hormone Blocking Drugs
It worries me that the side effects of these drugs can be so debilitating and disruptive to quality of life. More than that, I know quite a few who were on hormone blockers for the requisite period of time (usually 5 years) and suffered recurrences anyway. That indicates to me these drugs aren’t working as well as they are meant to.
A Good Article
While doing some research recently, I came across a lengthy article, on the NIH website, “Natural Products as Aromatase Inhibitors” . Be warned, that article will do your head in, unless you are a doctor, researcher or medical professional!
I will attempt to boil it all down into layman’s language for you – you can read for yourself all of the reasons why AIs are prescribed, how they work in breast cancer, and how scientists are actively researching many natural products to discover which ones can be utilized to help breast cancer patients. I know what you are really after — the list of natural things that exhibit AI activity.
18 Natural Aromatase Inhibitors
- Dioon Spinulosum – or gum palm, a cycad which grows in Veracruz and Oaxaca, Mexico
- Encephalartos ferox – also a cycad which grows mainly in Africa
- Riedelia – a genus of plants in the Zingiberaceae family, comprises approximately 75 species that are distributed among New Guinea and the Maluku and Solomon Islands
- Viscum album – a species of mistletoe, also known as European Mistletoe or Common Mistletoe to distinguish it from other related species. It is native to Europe and western and southern Asia
- Cycas rumphii – also a cycad, commonly known as queen sago or the queen sago palm, it grows in the Moluccan island group (New Guinea, Java, Indonesia)
- Cycas revoluta – also a cycad, native to southern Japan
- Alpinia purpurata – also known as Red Ginger, a native to Malaysia
- Coccothrinax Sarg – Coccothrinax is a genus of palms in the Arecaceae family, there are more than 50 species described in the genus, plus many synonyms and sub-species, and they grow in a variety of places
- Five red wine varieties, the most active being Cabernet Sauvignon from Tanglewood (France), the other mentioned was Pinot noir from Hacienda (Sonoma, CA)
- Brassaiopsis glomerulata – a deciduous tree found in North Vietnam
- Garcinia mangostana L. (Clusiaceae) – also known as mangosteen, has a long history of use as a medical plant, found mostly in Southeast Asia
- Euonymus alatus – also known as winged spindle, winged euonymus or burning bush, it’s a species of flowering plant in the family Celastraceae, native to central and northern China, Japan, and Korea
- Isodon excisus Kudo var. coreanus – a small herbaceous plant that grows in Western Asia (Japan, China, Korea)
- Scutellaria barbata – a plant used in traditional Chinese medicine, other names include ban zhi lian’, scullcap or skullcap, it grows in Korea and southern China
- Camellia sinensis – also known as green tea (easily obtainable every morning for breakfast!)
- Vitis L. sp – also known as grape seed extract, the report cited a study where a water extract of grape seed extract was utilized and it had AI activity
- Agaricus bisporus – also known as white button mushrooms
- Trifolium pratense L. – also known as red clover flowers. There is a lot of misinformation out there about red clover, please read my article Red Clover Controversy – Safe For Breast Cancer Or Not?
Update: See two more discussed below – selenium and pomegranate.
The article also mentioned that coffee, cocoa, collards, stout beer, tomato leaves and even cigarette smoke (!) strongly inhibited aromatase using a microsomal assay. I don’t know about you but I’m not eating tomato leaves or breathing in cigarette smoke intentionally!
Many of the above listed things are not currently being produced as natural supplements. I would suggest you print out this list and take it to your naturopath to see which ones would be available and safe for you to use. Some of the listed items will be easily available (like #9, #15, #16, #17 #18) and you could easily incorporate them into your diet.
Something not listed is selenium, we do have research indicating that it acts as a natural aromatase inhibitor, see my article Why Iodine and Selenium Are Useful For Breast Cancer.
2017 Update – I found an older study from 2010  indicating that the ellagitannins (phytochemicals) in pomegranates also had anti-aromatase activity. So make that 20 natural aromatase inhibitors (including selenium, above).
2018 Update – We can add mangosteen to the list of natural aromatase inhibitors. 
The above list is not exhaustive – the report did also discuss 125 flavonoids, 36 terpenoids, 19 peptides, 18 lignans, 16 xanthones, 15 fatty acids, 10 alkaloids, and 43 miscellaneous compounds having been evaluated but there was not sufficient information for me to feel it was worth listing them all.
Unfortunately, there is no information on dosages for any of the above nutrients, more information is clearly needed.
Just Remember Estrogen Is Not The Only Factor Involved In Breast Cancer
The important thing I would like you to take away from all of this is that we can drive ourselves crazy looking for the tiniest things that will give us an edge over this disease. I hope you don’t get bogged down in this. Please remember, estrogen is not the only factor involved in breast cancer. An overall anti-cancer strategy is to eat a healthy diet full of fresh organic fruits and vegetables and super foods, take the supplements that have research backing them (see my page discussing that topic), limit your exposure to toxic skin care products, get plenty of exercise DAILY and keep your stress levels down through the use of meditation or prayer.
You may want to read some of my other articles about aromatase inhibitors:
 Natural Products as Aromatase Inhibitors — https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3074486/
 Pomegranate ellagitannin-derived compounds exhibit antiproliferative and antiaromatase activity in breast cancer cells in vitro – https://www.ncbi.nlm.nih.gov/pubmed/20051378
 Xanthones from the Botanical Dietary Supplement Mangosteen (Garcinia mangostana) with Aromatase Inhibitory Activity – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2572570/
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