With all the loads of scientific data available that soy (even edamame) is not a healthy part of anyone’s diet, it shocks me how many folks are still on the “soy is good for you” bandwagon – even people who should know better like your doctor!
I just got an email from a reader the other day who had been to multiple doctors, both holistic and conventional, and all but one of them were telling her that plenty of soy in her diet would help her menopause symptoms.
I had another shocking conversation recently with a doctor of Internal Medicine who had no idea soy was a potent goitrogenic food and actively suppressed thyroid function.
Be careful folks. It’s dangerous out there! You really need to do your research and be on your toes at all times when it comes to nutritional advice even from someone in a white coat!
For those of you who just sat down because you are so taken aback by the notion that soy is not actually the healthfood you thought it was, here are 170 scientific reasons to back up this assertion.
Fermented Soy Fine in Small Amounts for Some People
Please note that fermented soy in small, condimental amounts as practiced in traditional Asian cultures is fine for those who have healthy thyroid function. Only miso, tempeh, natto and traditionally brewed soy sauce fall under this category. In addition, if you want to sprinkle a few edamame on your salad or have a few small cubes of tofu in your miso soup from time to time, that is fine too. A little soy lecithin in a nonGMO snack food from time to time isn’t necessarily a problem either. Just don’t make it a regular part of your diet!
If you have any sort of thyroid issues going on, however, it is really the best policy to avoid all soy all the time as soy is a potent goitrogen (thyroid suppressor) even if fermented.
Dangers of Soy #1
A 1991 study found that eating only 2 TBL/day of roasted and pickled soybeans for 3 months to healthy adults who were receiving adequate iodine in their diet caused thyroid suppression with symptoms of malaise, constipation, sleepiness, and goiters (Nippon Naibunpi Gakkai Zasshi 1991, 767: 622-629)!
Still think munching on edamame instead of popcorn is a healthy habit?
Dangers of Soy #2
Six premenopausal women with normal menstrual cycles were given 45 mg of soy isoflavones per day. This is equivalent to only 1-2 cups of soy milk or 1/2 cup of soy flour! After only one month, all of the women experienced delayed menstruation with the effects similar to tamoxifen, the anti-estrogen drug given to women with breast cancer (American Journal of Clinical Nutrition 1994 Sep;60(3):333-340).
Dangers of Soy #3
Dietary estrogens in the form of soy foods were found to have the potential to disrupt the endocrine system with the effects in women similar to taking the breast cancer drug tamoxifen (Proceedings of the Society for Experimental Biology and Medicine 1995 Jan;208(1):51-9).
Dangers of Soy #4
Estrogens consumed in the diet at low concentrations were found to stimulate breast cells much like DDT to increase enzymatic activity which leads to breast cancer (Environmental Health Perspectives 1997 Apr;105 (Suppl 3):633-636).
Dangers of Soy #5
The soy isoflavones genistein and daidzein appear to stimulate existing breast cancer growth indicating risk in consuming soy products if a woman has breast cancer. (Annals of Pharmacotherapy 2001 Sep;35(9):118-21).
Dangers of Soy #6
Direct evidence that soy isoflavones genistein and daidzein suppress the pituitary-thyroid axis in middle-aged rats fed 10 mg soy isoflavones per kilo after only 3 weeks as compared with rats eating regular rat chow (Experimental Biology and Medicine 2010 May;235(5):590-8).
Dangers of Soy #7
Don’t eat soy when you are pregnant ladies! Scientific research has shown that the developing male fetus which is exposed to soy phytoestrogens may suffer from higher susceptibility to prostate cancer later in life (Prostate 1994;24(2):67-78).
Dangers of Soy #8
Keep that soy away from your daughters! Dietary genistein (soy phytoestrogen) in developing female rats had the effect of significantly accelerated puberty (Toxicol Sci 1999 Oct;51(2):236-44).
In addition, early exposure to soy is associated with less female typical play patterns in girls at 42 months of age (Environ Health Perspect v. 119(12); Dec 2011).
Dangers of Soy #9
Hey guys! Soy protein powder strips your masculinity! A study of 12 men aged 18 years and older experienced a 19% drop in serum testosterone in only 28 days when supplemented with 56 grams of soy protein powder over that same time period (Prev 2007;16:829—33).
Dangers of Soy #10
Do NOT feed soy formula to your babies! Female newborns who are orally exposed to genisin, the glycosylated form of genistein (soy phytoestrogen) experienced harm to the reproductive system in the form of “delayed vaginal opening… abnormal estrous cycles, decreased fertility, and delayed parturition.” (Environmental Health Perspective 2009 Dec;117(12):1883-9).
More information on the dangers of soy infant formula even if organic can be found in this article.
Convinced yet? I don’t know about you, but ten reasons is plenty for me! Still interested to see the remaining 160 reasons? My friend Dr. Kaayla Daniel, author of the must read The Whole Soy Story, has compiled the rest of the list for you if you click here.
Sarah, The Healthy Home Economist
Sources and More Information on Women’s Health
The Dangers of Estrogenic Food, Herbs and Supplements to Breast Health
Breast Ultrasound Safer and More Effective than Mammography
When Breast Cancer Isn’t Bad News
Thermography: A Perfect Alternative to Cancer Causing Mammograms?
Even Organic Soy Formula is Harmful for Babies
Birth Control Pill Risks to your Future Child’s Health
Thank you… I had one wise mama in the 1990’s who was on top of soy research. She had been giving us some soy milk because in her hippie days soy was a mainstay. However she had an open mind and always did her research. She read an article about some girls who started their periods around age 4 because of all the soy in the diet. She promptly took us off of soy milk. We occasionally had tofu, and fermented soy products, but she was a watchdog when it came to reading ingredient labels(not that many things in our home had ingredients:D). I remember my friends thinking I was crazy as a teenager because I wouldn’t eat any snack foods that had soy in them. That was when all the teenage girls were drinking protein shakes and eating protein bars where the first ingredient was usually soy. I had one friend I convinced who suffered from terrible acne. After cutting out soy her skin became 90% better. I’m always cautious when people start promoting ONE food for everything and over everything else. Moderation and wisdom people! 😀 Thank you Sarah!
Thank you… I had one wise mama in the 1990’s who was on top of soy research. She had been giving us some soy milk because in her hippie days soy was a mainstay. However she had an open mind and always did her research. She read an article about some girls who started their periods around age 4 because of all the soy in the diet. She promptly took us off of soy milk. We occasionally had tofu, and fermented soy products, but she was a watchdog when it came to reading ingredient labels(not that many things in our home had ingredients:D). I remember my friends thinking I was crazy as a teenager because I wouldn’t eat any snack foods that had soy in them. That was when all the teenage girls were drinking protein shakes and eating protein bars where the first ingredient was usually soy. I had one friend I convinced who suffered from terrible acne. After cutting out soy her skin became 90% better. I’m always cautious when people start promoting ONE food for everything and over everything else. Moderation and wisdom people! 😀 Thank you Sarah!
:See I can say the same thing about meat and dairy. I had a friend that had a daughter that stated to early and come to find out it was because the hormones they give cows. And I know that the probable with GMO soy does have hi amount of hormone because I was told to get off Hydrogenated soy bean creamers and thing like that when I was 34. I was still doing GMO free soy-milk and my period started up again with not having one for 5 years and now I am 40 and I am still having a period. I know a girl at work that had very bad acne and she eat and drink dairy everyday and I told her get off the dairy she is a very happen person know.
Hi Sarah, Thanks for the post – it’s a great reminder. We really appreciate your site.
Thank you for this! We ended up giving my daughter soy formula for awhile and finally when she could have cows milk, we switched. I know now that I should have tried goats milk first and hope nothing comes of it.
Now in elementary school, we have to bring peanut free foods, so the school pushes a product called Wow Butter. It is toasted soy nut butter. And some kids eat it every day!! I wonder when people are going to see effects of this especially when combined with tons of processed Pre-packaged items that also contain soy. I wouldn’t even participate to sell the stuff in fundraisers.
You know before you freak out. You should be thinking of the process meat, white or brown not whole grain bread and milk. All are very much just as bad or even more! And as parents we need to show our kids why we need to eat whole foods like fruit and veggie. My kids know what going on but there friend are not being told by there parent.
however #2 I used to have very delyed period. Then I started eating soy 2 times a day. I was as regular as regular can be from that point on. Now with have baby however body changes and chemistry changes from that. soy gives me a dosie of a headache so i avoid it now. But I ate it all the time for over 10 years. May not have kid now if it wasnt for that as i could go 10 months without a period till i started eating it all the time.
See, that’s how I feel. Yes I do think a lot of the study’s done back in the 90’s might have been because of the GMO fact.
I really appreciate this post. I am not a soy user, but I didn’t know there were so many reasons not too! Another reason not to buy processed food!
What about the fact that most soy is GMO too?
That’s why I think her study’s she talking about was done back when they were still doing GMO. What about now with GMO free
GMO free? Lol good luck finding that, over 90% of the soybeans grown in the U.S. are genetically modified.
Alex, you are correct (thank you Monsanto), but if you buy organic, it cannot be genetically modified. And yes, processed soy foods can be bad, but if you are eating organic tofu or tempeh, or snacking on some organic edamame, it’s not really that bad. Again, in moderation. No one should be eating it at every meal, just like you shouldn’t be eating red meat or candy bars at every meal. This “soy is bad for you” craze is noted back to the fact that GM soy is pumped into almost all of our packaged and processed “foods.” If you’re eating that crap, you’re not only dealing with genetically modified “soy” but also tons of chemicals, corn syrup, and other crap.
“This “soy is bad for you” craze is noted back to the fact that GM soy is pumped into almost all of our packaged and processed “foods.” Not sure about that statement, however it is def not the most important reason to stop consuming Soy. Having switched to a Vegan diet, Soy milk was the primary source of Soy in my diet, and resulted in very painful fibroid breast tumors (never had them before). Upon examination, my Physician advised to cut out all Soy from my diet immediately. She was correct, they went away after just a couple of weeks and have only returned if I add soy back into my diet (even in small amounts), GMO or Organic. Bummer it’s in almost everything, but I def read labels to be sure.
Well back a few years when I was studying the origins of soy I found out an interesting piece of information. Soy has been grown for centuries but it was originally ONLY grown as a rotation crop but not as a food crop. It was not until the fermentation process was used did it enter the food chain..that is Natto, tempeh and MISO. Tofu is an overly processed non-fermented product and should not be eaten on a regular basis..ie..it is junk food. So for hundreds of years it was only a rotation crop and only in recent times was it added into the diet. And only in the last hundred years has it been considered a beneficial crop. The only benefit being…financial for the soy processors!
More than 99% of soy grown is genetically modified yes !
Sarah thank you yet AGAIN! You have taken me so far outside ‘my box’ that I can’t even see the darn thing anymore , anywhere!
At least this is one thing you and Kimberly Snyder agree on. She irritates the heck out of me. Saying dairy is bad, red meat is bad…I even commented on one of her posts asking her to please differenciate between real, raw, organic milk and the conventional kind and I never get comments back from her. When you posted the one about the dangers of having the “green drink” so much…she had a rebuttle (spelling) post about it and I commented on that too and no response. And she needs to take pictures of her and famous people off of her site…it seems like she does that to get people to come on board…so frustrating!! Sorry I just had to vent a little lol At least you’ll agree on the soy though 🙂
I worry about everyone going crazy over the Medifast diet! Half of my in-laws are really successful “Health Coaches” for Medifast. Every single meal, shake, bar, etc is full of soy protein in medifast.
One of my friends is a USANA rep and all their protein shakes and bars are soy based too! ISOLATE soy no less! Very concerning!
Fairly good article . Happy to see people spreading the truth , thhose of us vegans who did the research on soy years ago are always happy to find such reads !