Issue #286 March 5, 2015
Welcome to KnowYourThyroid.
There is a lot of talk about soy. Is it good, is it bad, do I eat it, do I avoid it. How do I know
10 reasons to avoid soy & stay healthy
Though most people associate soy with healthy eating, research has shown that soy is not healthy and it can cause health problems. Not only that, its widespread use can be destructive to the planet.
The key reasons
Soy is a legume, and as such, has the same harmful components that other beans do, but there is more. Some other harmful properties of soybeans are:
?Soybeans contain phytoestrogens, which mimic the body’s natural estrogen hormones. For men, this can lead to a testosterone imbalance, infertility, low sperm count, and increased risk of cancers. For women, it can cause estrogen dominance, which has been linked to infertility, menstrual troubles and cancer…
?These phytoestrogens are so strong that a baby consuming only soy formula is consuming the equivalent hormones of four birth control pills a day!
?The high levels of phytic acid in soy inhibit the body’s ability to absorb important minerals, including zinc, calcium, copper, iron and magnesium (which many people are dangerously deficient in already).
?Soy also contains protease inhibitors, which can block the enzymes that are necessary for the digestion of certain proteins.
?The goitrogens in soy are potent anti-thyroid compounds that can lead to endocrine disruption and thyroid disorders. Infants on soy formula have a much higher risk of autoimmune thyroid disease (note: cruciferous vegetables like broccoli, cauliflower and cabbage have these properties as well, though they are lessened greatly by cooking. Cooking does not remove these compounds from soy-based foods!).
?Soy is often promoted as an alternative food for celiac and gluten intolerant people, but its lectins can be harmful to the intestines and prevent healing even when gluten is removed.
?Many studies have found even more harmful properties of soy: This link has a summary of many studies done about the harmful effects of soy.
?Consumption of soy foods increases the body’s need for Vitamin D, Vitamin B-12, calcium and magnesium.
In addition to being harmful to our bodies, soy production is harmful to the planet and to the livestock who eat it as well. Almost all soybeans grown today are genetically modified and “Round-up ready.” They contain a gene that allows them to be directly sprayed with pesticides without dying. There is some evidence that this gene can mutate and create a pesticide-like toxin in the body.
This mutation means that soybeans can be (and are) sprayed with large amounts of pesticides and herbicides during their cultivation. In addition, soybeans strip the soil of many nutrients, leaving soil depleted (on a personal note, I live in an area where soybeans are grown, and have witnessed first hand how much soybeans are sprayed during their growth and how harmful these chemicals are to other plants and vegetation).
Animals who are fed soy can suffer many of the same health consequences as people who consume too much soy, and these harmful properties are then passed on in their meat.
Asian countries where soy is consumed in large amounts
I have often been asked the question regarding Asian countries where soy is consumed in large amounts, when I talk about the negative properties of soy. In this regard, it is assumed that people in Asian countries consume a lot of soy, and since they are thin, soy must be healthy.
It is important to note that people in these countries do not consume as much soy as we assume they do. In fact, in most places, soy-based foods are served as a condiment, not a main course and not as a replacement for animal protein. In addition, these foods are fermented or traditionally prepared, which minimises the harmful factors.
In many countries, soy-based foods are consumed with seaweed containing foods or traditionally made broths, which both have high nutrient concentration and can help mitigate the harmful effects of soy.
An inferior protein source
Besides the lectin and phytic acid in soybeans, they are not the complete protein source they are touted to be. Like all beans, they lack the amino acids Methionine and Cystine. While they are often promoted for being able to provide Vitamin B-12 to those eating a vegetarian diet, the Vitamin B-12 in soybeans cannot be used by the body and actually cause the body to need more B-12.
170 scientific reasons to avoid soy
With all the loads of scientific data available that soy 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.
Be careful. 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.
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 soy sauce (if traditionally brewed) 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. Just do not 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.
Soy Wake Up Call #1
A 1991 study found that eating only 2 TBL/day of roasted and pickled soybeans for three months in healthy adults who were receiving adequate iodine in their diet caused thyroid suppression with symptoms of malaise, constipation, sleepiness, and goitres (Nippon Naibunpi Gakkai Zasshi 1991, 767: 622-629)!
Still think munching on edamame instead of popcorn is a healthy habit?
Soy Wake Up Call #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).
Soy Wake Up Call #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).
Soy Wake Up Call #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).
Soy Wake Up Call #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).
Soy Wake Up Call #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).
Soy Wake Up Call #7
One should not eat soy when one is pregnant. Scientific research has shown that the developing male foetus which is exposed to soy phytoestrogens may suffer from higher susceptibility to prostate cancer later in life (Prostate 1994;24(2):67-78).
Soy Wake Up Call #8
Soy needs to be kept away from daughters. Dietary genistein (soy phytoestrogen) in developing female rats had the effect of significantly accelerated puberty (Toxicol Sci 1999 Oct;51(2):236-44).
Soy Wake Up Call #9
Soy protein powder can strip guys of their 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 gram of soy protein powder over that same time period (Prev 2007;16:829–33).
Soy Wake Up Call #10
Soy formula should not be fed to 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).
Aren’t these reasons convincing enough? I think 10 reasons are plenty. Nevertheless, those who are still interested to see the remaining 160 reasons, should look for Dr Kaayla Daniel’s (author of the must read The Whole Soy Story) list!
(The author is president, Academy Of Nutrition Improvement. He can be contacted at firstname.lastname@example.org)
KnowYourThyroid.com, including all associated social media, is for informational purposes only and
should not be considered a substitute for consulting your medical professional regarding medical advice
pertaining to your health. KnowYourThyroid.com is not responsible for any loss, injury, or damage that
allegedly arises from any information published on this website and related social media sites. You are
responsible for any actions you take regarding your medical care.