Soy: Healthy Or Dangerous? | Andrew Weil, M.D.


In general, I recommend decreasing the amount
of animal food that you are eating, but that doesn’t mean become a vegetarian, and trying
to increase vegetable protein in the diet. There are many wonderful forms of soy that
you can use as vegetable protein, other beans also. There is a lot of controversy about
soy out there and if you go on the Internet you can find all sorts of paranoid articles
about the dangers of soy. And now there are some medical experts talking about the dangers
of soy of being an endocrine disruptor, promoting cancer and so forth. The epidemiological evidence
from Asia is extremely reassuring that populations that eat a lot of soy regularly have better
health, better longevity, and in particular lower rates of hormonally driven cancers.
Japanese women on traditional diets have one of the lowest rates of breast cancer in the
world – if they move to other countries and adopt their ways of eating, western ways of
eating, rates of breast cancer rapidly go up. Japanese men gets prostate cancer at the
same rates as American men but the prostate cancers in Japan are much less aggressive
– there is a much lower tendency to leave the gland and spread and be deadly than in
America. I think these are both effects of soy diets. But Japanese, although they eat
soy at every meal and they do so from infancy to old age, they are eating whole soy foods
in moderation. They are not eating fractionated soy foods, they are not eating functional
foods spiked with elements of soy, and they are not taking supplements of soy isoflavones.
A lot of the products, if you look at the ingredients it will say soy isolate, or isolated
soy protein, those are fractionated elements of soy and we have no epidemiological evidence
about their safety or benefits. I would advise avoiding products made with those things and
that includes a lot of those fake meats out there, you know fake hotdogs and lunchmeats,
all things made with soy isolate. There are a few that aren’t: a brand called Tofurkey
that makes sausages and sliced things and the first ingredient is organic tofu. So by
whole soy foods I mean edamame, which are great, soy nuts, soymilk, tofu and tempeh,
those are whole soy foods. I would stay away from products made with soy isolate, isolated
soy protein, I would not take soy isoflavones as a supplement, I wouldn’t eat functional
foods like cereals or soups that have soy isoflavones added to them. I think moderate,
regular consumption of soy beginning as early in life as possible is good. With breast cancer
protection, it seems the major effect comes in childhood and adolescence. It’s an effect
of soy in the diet on developing breast tissue that confers resistance to breast cancer throughout
life, so that’s an important message to get to kids. I expect that the prostate cancer
protection works the same way. We don’t know if an America woman suddenly begins eating
soy in mid-life that she’s going to get the same benefits in terms of breast cancer protection.
If you look at these isoflavones, these so-called phytoestrogens in soy that have estrogen-like
activity, some of them if you take them in test tubes, some of them stimulate breast
cancer cells to grow and some of them inhibit them from growing. I think when scientists
look at that, this is cause for concern that some of these elements might actually promote
cancer. But this is the way nature works and it tends to produce things that both push
and pull that have opposite effects on the same thing and when you put them in the body,
the body knows how to deal with them. To me, I think whole soy foods in moderation are
very beneficial for a lot of reasons and I think that substituting them for some of the
animal foods in the diet is a useful change. You are getting a better fat; the fat in soy
is fine, it’s when you isolate this as refined soy oil that it’s a problem of excessive
omega-6s. You are getting these hormonally active things that are beneficial, you are
getting fiber, you are getting a good form of protein, some slow digesting carbohydrate,
for all those reasons it is good.

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Reader Comments

  1. 小橋愛子

    they are too afraid of consuming soy because they eat GMO soys.. but in fact, we, indonesian- has tempeh and it's reach of phytoestrogen also,but many indonesian guys have normal thyroid levels.. so. i like this video..just ban the GMO and isolated or whatever modified soys.. but not with organic ones..

  2. Rita Rita

    Jésus Christ peace be upon him is just a messenger from lord , he is not lord , he had a mission in earth , and do not say he is lord , please go back to your bible and find out the reality , because you are just following what your society does , without thinking …and Jesus is NOT lord , he is a messenger sent by god to his people

  3. smegma jim

    only formented soy is good for you.  Asians in Asia dont drink soy milk or have tofu steaks for din din either.  Eating soy beans give you more of the toxins.  Stay away its GMO poison too!

  4. Judith Dew

    Dr. Weill wants you to think he's enlightened.  He's not.  He doesn't know what
    he's talking about – in more ways than one.  Read The Whole Soy Story for the
    truth.  He's repeating all the soy propaganda – as though they're facts.  The Jap-
    anese do NOT eat soy at every meal.  He's never been to Japan.  In fact, he
    is so dead wrong – not just about soy – but about other important things.  What
    a joke! 

  5. Judith Dew

    Read The Whole Soy Story by Kaahla Daniel.  Also, learn what you can about
    eating right for your metabolic type.  Dr. Weill is probably guiding you along a
    path that just so happens to fit with your type.  Dr. Weill knows nothing about
    cancer.  He has grown a following by the people who respond to his opinions,
    ONLY because they fit.  There are always people who will fit with a doctor's
    recommendations, but he doesn't address the ones who don't.  Half the popu-
    lation will NEVER fit in any way with his recommendations, because their
    metabolic types responds.  I cured my own breast cancer and have been re-
    searching for years.  He's all wet.

  6. captainjack77

    There are actually many studies in regards to the benefit of isolated soy proteins – the results show a negligible, or nil effect. 
    The only benefit of soy comes from whole soy consumption. Still only a 3-6% reduction in LDL cholesterol levels, but the intake of new soy should also displace some animal protein previously in the diet, which will also help lower to LDL. 

  7. Andrea Mahia

    So what about Soy milk? I'm lactose intolerant. So that raises some questions for me. I know it all depends on how it was processed.

  8. May

    So due to the oestrogen in the soy beans, would (excessive) soy intake have any effect on a female taking birth control? Or was using any kind of oestrogen inhibiting contraception for that matter? I'm not on BC myself but I'm quite curious.

  9. Slobodan Dzikoski

    Soy products, both soy protein isolates and soy isoflavones, induce profoundly beneficial effects on the human cardiovascular system. Early human studies showed that long-term intake of soy protein rich in isoflavones could improve blood lipid profiles, at least in part by increasing expression of receptor molecules that take up LDL cholesterol.21 In fact, soy protein and isoflavones have universally been shown to lower LDL cholesterol and triglycerides, while some studies have also documented increases in beneficial HDL cholesterol as well.22,23 Along with phytic acid, another soy component, soy isoflavones significantly lower homocysteine levels and positively influence other biomarkers of cardiovascular disease risk.24-2

  10. Redhead Moxie

    Over 93% of soy produced in the U.S. is genetically modified and the crops are sprayed with the herbicide Roundup, which is associated with adverse effects on health.  The high levels of phytic acid in soy inhibit the body’s ability to absorb important minerals, including zinc, calcium, copper, iron and magnesium . Soy contains large amounts of biologically active compounds called isoflavones,(endocrine disruptors) which are chemicals that interfere with the normal function of hormones in the body function as phytoestrogens.  The Asian culture discovered early on the toxic nature of soy and use only fermented soy.  They also only use it as a condiment, in small amounts, and not as a meal staple.

  11. Nr M

    Ridiculous! He has no clue! Never really did like this guy! Pfffft!
    He has not done his homework or seem to know the difference between fermented and unfermented soy. Not mentioned the anti-nutrients, enzyme inhibitors. And not to mention that Most all soy In the US is genetically modified. Who's side is he on? Evil?!or ignorant?

  12. Issy Hamdulay

    Sounds like a dodgy promotion….Doc ?? The research is overwhelming against it's overall safety……period. I'll stick to Dr Mercola's honest and reliable advice. 

  13. tkarlmann

    It is absolutely staggering to me that this man is able to quietly discuss soy and all of its international regional dietary impacts without ever mentioning GMOs.  Over 90% of the soy in the US is genetically modified.  I seriously wonder where folks like this presenter here get their funding.  Are they oblivious to the GMO issue, or have they bought into one of the two faces that Monsanto puts out: FACE1) GMO soy is no different from organic soy; FACE2) Oh, our GMO soy is completely different from any other soy?  FACE1 is used to talk to the public, while FACE2 is used at the US patent office.  You be the judge — in the meantime let's get GMO-'foods' (some might call them 'Frankenfoods') labled as such!!!!!  For now, he's not my "trusted health advisor"!

  14. Skepti Cat

    For starters, Asian populations TRADITIONALLY ate soy as a CONDIMENT!! Not as a meal. AND, it was TRADITIONALLY FERMENTED soy. Miso, tempeh, natto. Tofu is not healthy. Neither is soy milk.
    Unfortunately, Asian populations have more recently acquired more of a western food philosophy. Look at their rising obesity rates and other health problems.
    Secondly, MOST soy in the US is GMO. Frankenfoods.
    And probably most important is that soy is an endocrine disruptor (think thyroid). Is it any wonder there is an epidemic of hypothyroidism (sluggish thyroid) in the US? So, whether organic (non-GMO) or GMO, soy is not good for you.

  15. Robert Henry

    Newest Research on Why You Should Avoid Soy:
    1996 study linking soy WITH breast cancer, not protecting against it.
    Also, Asians throughout the world have higher rates of thyroid cancer.
    http://www.mercola.com/article/soy/avoid_soy2.htm

  16. Kathleen Woolever

    You are a brilliant Man…I wish you were near me…I love your advice and take it!!! Thank you Dr. Weil for clearing this up…I wish all Americans would listen to you, as I do 😉 Hugs, Kat

  17. sam jose

    They're eating 'fermented' soy Doc.. see one episode of Bizarre Foods with Andrew Zimmerman. This is supported by a NIH study proving fermented soy is the only rendering suitable to human digestion.

  18. Ken Personal

    CATEGORY : Endocrine disruptor . Zenoestrogen (strange foreign estrogen).
    Examples FOUND IN : Gains,  beans, peas, some fruits, broccoli, cauliflower, soy ; also as concentrated extracts from these foods .

    Mainly belong to a large group of substituted natural phenolic compounds: the coumestans, prenylflavonoids and isoflavones are three of the most active in estrogenic effects in this class.

    The best-researched are isoflavones, which are commonly found in soy and red clover.

    Lignans have also been identified as phytoestrogens, although they are not flavonoids.

    Mycoestrogens have similar structures and effects, but are not components of plants , these are mold's .

    Metabolites of Fusarium, a fungus that is frequently found in pastures as well as in alfalfa and clover.

    Although mycoestrogens are rarely taken into account in discussions about phytoestrogens, these are the compounds that initially generated  interest on the topic .

    https://plus.google.com/u/0/111536759455073094610/posts

  19. neva lans

    soy that Japanese people eat is FERMENTED and therefore it's not that bad for you. It would be better if Dr.Weil mentioned that, in modern diet that uses soy there is almost none of that kind of food there.

  20. RealTalk

    Soy in Japan at the time of finding these health benefits was fermented NOT genetically modified.
    Today most of the soy in circulation is genetically modified. So how it reacts with your body is very different.

  21. Barbara Wasilak

    weil got it all backwards, the Asian people eat FERMENTED SOY in all amounts, maybe teaspoon a day!! look at american food labels: soy, wheat, concentrated high fructose. syrup!!!!!!

  22. Jeff Miller

    What a bunch of gas bags commenting here. Round Up is a weed killer, why would anyone apply it to a food crop? I`ve been eating tofu for years with no problem.

  23. Quantum Chang

    Even unfermented soy has been found to be an estrogenic antagonist. Unfermented soy such as tofu and soy milk that is eaten at breakfast has been saving Asians from the curse of the Western cancer epidemic. Leave it to the Asian to lecture you guys on the benefits of soy. If your mother and father didn't teach you to eat soy when you were a toddler, then don't bother to preach about soy.

  24. Lion Entity

    Soy is highly acidic. It is not a natural grain. Japanese and Chinese are absolutely not the healthiest people in the world. I can show you people who live above 100, and eat no soy whatsoever, no rice either. Chinese are very unhealthy.
    Your diet needs to be alkaline, and preferably raw.

  25. General Lee

    I just watched a Dr Mercola video on soy and he says to stay away from soy except for the fermented types. Now I am more confused then ever. I drink a ton a soy milk every day. I also eat tofu. Who is correct? Now I am even more confused 🙁

  26. chilly yilly

    Water and Canadian soybean are healthy and makes you live longer than drinking alcohol and soda all of that high blood pressure and damage liver blackout. facts.

  27. Bakki Boo

    Japanese soy is fermented too ….I just got a brainwave i drank a lot of protein powder shakes about a year before I got diagnosed with Breast Cancer Hmmmmmmmmmmmmmm…. I saw it had those Soy Isoflavones & all sorts of Soy moderated products …OMG what did I do!

  28. Akuma

    Lmao… these comments. So many keyboard warriors with PhD's. It's rather simple… as with most everything, stick to organic/non-gmo and you'll be okay.

  29. thinkin outloud

    Haha yeah, Soy is all fine and dandy if it's seeds have not been infused with "Roundup" but as we know, the food additives in the American diet are slowly killing us

  30. dev bachu

    So mustdead meat an it's ok to eat but soy an soy products what about it I just made some soy milk is it good or bad but the chemical injected into meat is better ?? Bull with shit on it can men be femaine using soy milk daily my God nothing good to eat

  31. ionic vibrations

    Soy can reduce risk of prostate cancer in men. It is very important for the soy you consume to be non-gmo and organic.

  32. yves2075

    I eat natto, almost one portion a day (I have serious cardiovascular disease). You haven't listed natto as one of the forms of "beneficial" soy. Does that mean you view natto as possibly a bad form of soy? Just wondering, your opinion would mean a lot to me. And, keep up the work!

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