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Healthy Home Economist / Archives / Healthy Living / 170 Scientific Studies Confirm The Dangers of Soy

170 Scientific Studies Confirm The Dangers of Soy

by Sarah Pope / Affiliate Links ✔

Dangers of SoyWith 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

Best Mammogram Alternatives

When Breast Cancer Isn’t Bad News

Komen (Not) for the Cure

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

Is Your Egg Allergy Really a Soy Allergy in Disguise?

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Category: Healthy Living
Sarah Pope

Sarah Pope MGA has been a Health and Nutrition Educator since 2002. She is a summa cum laude graduate in Economics from Furman University and holds a Master’s degree from the University of Pennsylvania.

She is the author of three books: Amazon #1 bestseller Get Your Fats Straight, Traditional Remedies for Modern Families, and Living Green in an Artificial World.

Her four eBooks Good Diet…Bad Diet, Real Food Fermentation, Ketonomics, and Ancestrally Inspired Dairy-Free Recipes are available for complimentary download via Healthy Home Plus.

Her mission is dedicated to helping families effectively incorporate the principles of ancestral diets within the modern household. She is a sought after lecturer around the world for conferences, summits, and podcasts.

Sarah was awarded Activist of the Year in 2010 at the International Wise Traditions Conference, subsequently serving on the Board of Directors of the nutrition nonprofit the Weston A. Price Foundation for seven years.

Her work has been covered by numerous independent and major media including USA Today, ABC, and NBC among many others.

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Reader Interactions

Comments (370)

  1. Annie Galanda via Facebook

    Apr 29, 2014 at 9:00 am

    I have in the last year cut it out of my household also!! Its a female plant and contains high levels of estrogen!

    Reply
  2. Jen Fisher via Facebook

    Apr 29, 2014 at 8:30 am

    I didn’t read the article but for me , personally non GMO, granulated organic soy had been a lifesaver. My doctor , a Traditional Chinese Doctor, American but trained in Shanghai, suggested I started to use it got my hormone imbalance. ( I’m 43) and my very moderate hyperthyroidism and it has proved my health immensely. He agrees that our American, nonorganic , GMO soy is very bad, but after years of studying women’s health in Asia, where a very different soy is eaten, convinced me to try it. So , like everything, there is a variety of science to support whatever you want to believe.

    Reply
    • Phil

      Jun 12, 2014 at 7:33 pm

      Hi Jen, I can totally believe that. I have lived in Japan and so many of my wife’s relatives (Japanese) have been eating / drinking soy all their lives a lot of them are in their late 80’s and up to their mid 90’s. Fit as, and never had a problem with it causing any health issues. Makes you wonder huh?

    • Allison

      Oct 4, 2014 at 8:48 am

      I agree with you completely. Yes, obviously if you are consuming pesticide ridden crops produced in the masses you are going to disrupt hormone levels. I also consume non GMO organic soy to help balance hormone levels.

  3. Sarah Dochow via Facebook

    Apr 28, 2014 at 8:54 pm

    There isn’t a single RCT on that list! Studies on rats or that have 6 participants are not considered conclusive research. I agree that conventional and processed soy isn’t health food and likely causes health issues but tofu, tempeh, miso, edamame, etc can be used moderately and have health benefits. My friend/colleague, an oncology RD (with an MS in dietetics from an integrative health university), just wrote a blog on this same thing and came to a different conclusion. http://www.becomingginger.blogspot.com/2014/04/soy-let-me-convince-you-it-is-safe-for.html

    Reply
  4. Brittany Graham Howell via Facebook

    Apr 28, 2014 at 8:37 pm

    Bekah Crowell soy is on the common allergen list so maybe Alana is reacting to that?

    Reply
  5. Pamela Mauzy Moynihan via Facebook

    Apr 28, 2014 at 6:02 pm

    I am an advocate against soy too – especially people over 40! Thanks for sharing!

    Reply
  6. Christian Berthaud via Facebook

    Apr 28, 2014 at 4:43 pm

    Gives you kidney stones as well due to high level of oxolate

    Reply
  7. Sarah Abuelkhair via Facebook

    Apr 28, 2014 at 3:15 pm

    Sarah Pilling yes! Thank you for sharing this

    Reply
  8. Diane O'Neil via Facebook

    Apr 28, 2014 at 2:19 pm

    I avoid it. Can’t eat anything with it without having a reaction.

    Reply
  9. Paul Aloise via Facebook

    Apr 28, 2014 at 2:18 pm

    Brittany, all milk is bad. Except from the mother to child!!
    Soy is poisonous, it must be processed to make it consumable!!!!

    Reply
  10. Rivkah Edelman Hubbard via Facebook

    Apr 28, 2014 at 2:08 pm

    Allison Hubbard thought of you

    Reply
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