Doctor's Note

For background on the role mushrooms may play in suppressing breast cancer growth, see Vegetables Versus Breast Cancer, and Breast Cancer vs. Mushrooms. Green tea may also help account for the Asian Paradox; which type is best? See Antimutagenic Activity of Green Versus White Tea. And, what may be the best way to prepare it? See Cold-Steeping Green Tea. Also, see Breast Cancer Survival and Soy. However, it may be possible to overdo it; see How Much Soy Is Too Much?

For further context, check out my associated blog posts: Ergothioneine: A New Vitamin?Mushrooms for Breast Cancer PreventionWhy Less Breast Cancer in Asia?The Best Way to Prevent the Common Cold?; and Go Nuts for Breast Cancer Prevention.

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  • Elpoo

    Pass the shrooms! Just a note – the top source does not link to the right article. Links to article on childhood soy consumption.

  • Tko

    My friend lives in US is a very healty and muscular 70 years old Japanese woman who swims 11 laps a day, and eats many mushroom. She got the brest cancer a few years after she started taking the hormone replacement treatment from the Gynocologist.

  • JohnC

    Is there a worry about what mushrooms might be grown in? Someone was recommending mushrooms from Monterrey mushrooms because they also contained vitamin D. According to Monterrey’s website, one of the things it uses as substrate to grow them in is “protein meal.” Researching the rendering industry, “protein meal” may not be something you might want to risk consuming. Are there “clean” or vegan sources for commercially grown mushrooms?

    • Rph1978

      Mushrooms naturally contain Vitamin D2 and the Monterey mushrooms lists their D content as 400 iu per 84 g serving. They list it as 100% Daily Value which is low and based on an old (1977) recommendation. The Vitamin D content of mushrooms can be increased by UVB and UVC irradiation.(J Agric Food Chem. 2009 Apr 22;57(8):3351-5.) You may want to try growing your own mushrooms. You can buy mushrooms kits:
      They use peat moss and compost as the growing medium but you might want to contact them about the composition of the compost.

      • JohnC

        Good idea to try growing mushrooms. But the kits works out to about 10 bucks a pound for shrooms if you include shipping.

    • JohnC

      I sent an email to Monterrey asking the source of “protein meal” (indicated on their website). Here is their response:

      “The term protein meal is misleading. We grow mushrooms in compost that we prepare according to specific formulas.
      The compost is primarily wheat straw, which has a lot of protein, in
      addition to other products that supply nitrogen. The supplements we use are soybeans and feather meal, both very high in protein. We use a lot of protein in order to get a fast and consistent growth.
      I am not aware of any food company that uses rendered animal products in items for human consumption; the risk of e. coli is too great.”

      I am sending them back a reply indicating that feather meal IS rendered
      animal products and that it is contaminated with arsenic (learned from
      Nutritionfacts). Not to pick on Monterrey, other commercial growers
      likely use similar substrates.

    • Thea

      JohnC: re: “Is there a worry about what mushrooms might be grown in?”

      I thought you would be interested in the company where I bought a couple of mushroom kits from:

      They grow their mushrooms from recycled coffee grounds. I don’t usually like the process of growing things, but this was super fun and super-easy. Even I could do it. And the mushrooms came out beautiful. Yes, growing mushrooms from a kit is not the cheapest route to go, but it is sure satisfying to me to be able to eat very fresh mushrooms that I grew myself. Great project for kids too. And I like the above company for how they appear to be responsible concerning the environment.

      Good luck if you decide to try growing your own mushrooms. Hope you found this helpful.

  • Karen

    Couldn’t it also be what Asian women are NOT eating, like maybe dairy?

    • Sandi

      Have you read the book, ‘Your life in your Hands’ regarding dairy consumption by Asian women? It makes very interesting reason.

  • Thea

    This is an awesome video. I love powerful and practical videos like this one. Most of Dr. Greger’s videos are great. I don’t usually bother logging in to rate them. But I did this time. 5 stars!

  • Michael

    In Table III, why don’t the numbers add to up 1,009 in both the cases and the control groups? They have the dietary intakes divided in quartiles, but they don’t add up.

  • After attending your talk here in San Diego where you mentioned your tea gulping habit, I began mixing white and hibiscus tea with my regular green tea all-day drink. A few weeks later I began adding a pinch of the 14-mushroom powder blend from along with a pinch of amla powder (another of your videos) and a pinch of fenugreek powder (yet again).

    Tea is a wonderfully easy way to incorporate these into our diet.

    Thank you for the great videos!

  • There is such a huge difference between the asian diet and the US diet. how can we pinpoint just one or two items and call it the source? Asian diets are heavy in seafood which is rich in omegas, asian diets contain several unique varieties of mushrooms, root vegetables, greens, and do not contain heavy doses of several of our American diet bad guys, like wheat, beef, dairy…while they do eat these things, it’s not a regular part of their diet. In the US, we might eat wheat and dairy at every meal! Portion sizes are smaller and I found the people I talked with to be very aware of what goes into their food. They ate at home more often, were wary of fast food, particularly McDonald’s (which is different there) and reserved it for very special occasions. We need to get serious about our basic health needs in this country. we allow the FDA to run virtually unchecked, and things like GMOs and additives are introduced to our diet with almost no warning. We don’t insist companies prove it safe, we wait for issues to arise before we determine things to be unsafe. sure, eat mushrooms, mushrooms are packed with trace nutrients. drink green tea, herbal tea, whatever awesome, but also, stop eating processed food. stop eating at fast food restaurants. eat whole grains, avoid GMOs and additives. Reduce the amount of meat and dairy you eat. (I did not say eliminate, so don’t yell at me about vegetarianism, I love meat but I also have a family history of colon cancer, and I KNOW it is triggered by over-consumption of meat.) eat more vegetables and WHOLE fruit. do you even know what is in your juice in America? Google that. it’s disgusting. I’ve lost 50lbs over the course of two years and all I changed was what I eat. my cholesterol dropped 35 points (it wasn’t high, but now it’s awesome) my triglycerides went down, every aspect of my health is improving.

    • beccadog

      China and Asia have GMO’s, also. But they have mandatory labeling and the right to know unlike the USA. (We need more activists in the USA, who contribute money when they live out of state of California (like I do). I contributed part of my food allowance for several months to the Yes Proposition 37 Right to Know campaign in California, even though I could not vote. BTW, supporters were outspent by 30 million dollars, but lost by a very narrow margin. The vote will come up again in 2013. Perhaps you can join us in contributing to the Right to Know. Where California goes so goes the rest of the country!

      My guide in China pointed out that limited dairy is used there. They use yogurt to speed digestion along and keep the fluids moving throughout the body. They do not use sugar or flavored yogurt, even though their yogurt is from animals.

      Portion sizes of meat are smaller. There is some chicken, duck, pork, and occasionally beef, and of course lots of seafood. But, they use more vegetables and rice than meat, not the other way around as it is in the USA. I found I could not eat all the food served to us. The portions of veggies in soups, and entrees was huge!!!!

      The Chinese also walk a lot because driving and parking is so difficult. We Americans are spoiled with our government subsidizing Big Oil to keep the cost of driving a vehicle down and our waist line growing. I think the USA economy runs on making people sick!

      BTW, in China, human manure is used to grow food. Coal is the predominant fuel and coal dust is everywhere, even in the air along the Great Wall. But, the food is cooked at high temperatures, I presume to reduce bacteria in the human manure. The entire country is very toxic –the soils, the air, the waters and there is zero regulation.

      Chinese medicine is primarily plant based like their food, it is not made from petrochemicals unlike in the USA, although they may be using recombinant DNA in China alike the USA. I’ve seen lots of patents for biotechnology and toxic herbicides in China and Asia. Although both the continent and the country has the right to know, unlike North America. More at:.


    • Val

      Theresa, I also have family history of colon cancer (dad in 1986 and brother in 2010) so I am WITH you on your statement! Both were somewhat depressed around the time of diagnosis, to me, another factor…when we are depressed, I am sure it affects our immune system. My dad’s doc told all of us: “CROWD your plates with vegetables and STOP eating all processed and red meats.” I took that advice to heart. (Plus I never smoked…entire immediate family were smokers though all had quit)…but DIET is the most important and we GET TO CHOOSE what we eat I ADORE Dr. Greger’s work and his videos…I’ve tweaked my diet to include green tea and hibiscus tea every day…am growing lots of my own greens…and I feel wonderful at age 56 and had a pretty awesome carotid scan result 3 years ago..”no plaque burden” the Cardio-Risk report said. Am hoping my colon is as clean as my carotid artery…seems from all I researching that whatever is great for our hearts is also great for our colon, kidneys, brain, lungs, skin, etc.!

    • baggman744

      Asia is very densely populated with many different cultures and diets, even within the same country. I mean, in just two countries, China & India, you have about 1/3 the world’s total population. Then you have old Asia, and modern Asia, whose diets vary greatly. So I kinda challenge what is an “Asian diet”?

  • rachel vegetarian

    I agree, what they are NOT consuming is as important. They do consume
    less meat and much less dairy. I think everything taken into consideration
    is more important than isolating certain foods or nutrients, its’ the WHOLE
    picture that counts like lifestyle, stress, exercise and so on.

  • “Women with dense breasts have been shown to have a four- to six-fold increased risk of developing breast cancer.” Asian women, in general, have less dense breasts.

    • That is the case in my family…mom, aunt & BOTH sisters had breast cancer. We were part of the original breast cancer gene studies. I’ve been eating a low-fat vegan diet for most of 32 years which includes lots of shrooms and soy, among many other cruciferous and varieties of plants. Plus running. It seems to be magical on many fronts besides avoiding cancer. 3rd in state Senior Games in the 200, 400 & 1500 meters. Plants rock!

    • Camilla Dahl Alvestad

      Never heard of this, I read the article but I did not understand how you know whether you have dense breasts? Can this only be determined through examination by a doctor?

      • Breast density is not based on how your breasts feel during your self-exam or your doctor’s physical exam. It is determined from a mammogram.

        • Camilla Dahl Alvestad

          Ah right. I am only 30 so I have never had one. Guess I will find out in time then. Up on till then Ill just eat my mushrooms and try to stay healthy :) Thank you for your reply, learned something new today!

  • As usual, great info. As a cooking instructor for The Cancer Project, and in other talks, I always get the soy and cancer question. Thanks for the concise info on that. I’ll refer to this often.

  • CaveChick

    I think lower cancer rates are attributed to what IS NOT eaten to a high degree. No dairy products and very little animal protein is key!

  • Norna

    I actually just read a report recently by a scientist. Her husband, who is also a scientist, inquired while in China why 1 in 10,000 women get breast cancer and found out it was because they don’t eat any kind of dairy. When his wife took all dairy out of her diet, in a very short period of time, her numbers they chart went straight down off the chart. Her oncologist told her that meant that her cancer was completely gone, not just in remission. We in the Western world are the only mammals on this Earth that drink another mammals milk meant for their offspring. I, myself, haven’t had cow’s milk in 6 years. I love either Almond or Brown Rice milk.

    • blueturtles

      Keep in mind that the milk we drink in the US is loaded with hormones. That is more likely to be affecting breast cancer rates than the milk alone – I mean, hormones designed to make cows produce more breastmilk is likely going to affect human breasts, too.

      • baggman744

        Hormones, steroids, antibiotics, and fed an unnatural diet of GMO soy & corn. Its a wonder they even survive to produce milk.

  • rick

    90% drop with small amount of green tea and mushrooms! Once again my head is spinning. Is this just what one study found and really not completely true? If it really is true then why does the American Cancer Society get this published everywhere?

  • Sebastian Tristan

    Is there anything Green tea cannot do?

  • Diana

    I loathe mushrooms! Would taking capsules of powdered mushrooms be an effective solution?

  • k.I

    Shitake mushroom is often sliced thinly and put in Miso soup , maybe half a mushroom per serving at breakfast and dinner time with other dishes. The traditional basic broth is from Konbu (seaweed) where the Miso paste is put in to make the soup.
    This is consumed (or used to be) daily or at least a few times per week in Japan. (Same with Seaweed, in Miso or as a salad with a citrus type dressing).
    However in the past 20 – 30 years I observed the Japanese dropping the traditional diet and consuming dairy and meat (bacon , beef) instead, because we were taught that it gives you more energy and strength. We were kind of brain washed I guess.
    The wealth of information here has inspired me to go back to my traditional Japanese diet , thank you Dr Greger !

    I am the second category, ate Nori, Tofu etc daily as a child in Japan, then dropped it after moving overseas in my 20s, it’s been a few decades. Hopefully it’s not too late.

    • Thea

      k.l : That’s so interesting to learn about your childhood diet compared to what happened over time. I think it is great that you are trying to get back to a more traditional diet. I hope it works well for you! Thanks for sharing.

      • k.I

        Thank you Thea, I am putting a Vegan twist to the traditional Japanese diet now, the first thing that convinced me was how better I felt after going Dairy free. After that I stopped the animal based proteins. Visiting this site will keep me motivated.

  • Is Reishi Mushroom Powder as effective (or effective enough) for preventing cancer as eating fresh/dried mushrooms? Such as adding the mushroom powder to smoothies, soups?

  • Robert Haile

    Why do you think the rate is so low in Central America?

  • Terri Seip

    Do the mushrooms have to be raw?

  • Dag Rene

    I found no better place than this old video to place my Q: I stumbled upon the Chaga Mushroom (Inonotus Obliquus) in my search for health benefits. It apparently boosts the immune system, lowers blod pressure & cholesterol, anti cancer, anti inflammatory etc. Possibly the highest antioxidant level of any food/ supplement. Been in use for hundreds of years in Russia, China and Korea. There are multiple studies which backs these findings. I would love it if you can make a medical evaluation and recommenadation for this topic. Or that research to date is too vague to conclude.