Benefits of Soy & Soy Protein Dangers | Natural Health Blog

Date: 09/11/2012    Written by: Jon Barron

Benefits & Dangers of Soy Products

soy products

I've never made a secret of the fact that I'm not a big fan of the benefits of soy, at least when used as a primary protein source. Soy products are by no means as safe or nutritious as their proponents would have us believe. Then again, on the other side of the equation, the dangers of soy are nowhere near as pronounced as many of its detractors claim. On a good-bad scale, they probably come in at a 35:65 ratio, with the 65 lined up on the negative side. However, a great deal depends on which soy products you use and what your age is. 

The History of Soy

The proponents of the benefits of soy state that the value and safety of soy products have been proven over several millennia of use in East Asia. Unfortunately, that's only half true. Yes, soy has been grown in Asia for several millennia, but not as a food. In fact, it was originally used only in crop rotation to fix nitrogen. For a long, long time, soy was not considered suitable for eating, at least until fermented products such as soy sauce, tempeh, natto, and miso came along. In America, until the 1920's, soy was grown only for its industrial by-products. Then as an animal feed -- still its primary use -- and only more recently has it been used as a primary protein source. In Japan, the average consumption of soy runs about 8-9 grams of soy products a day. That's less than two teaspoons. Again, most of that's fermented (miso, soy sauce, and natto) or precipitated (tofu).1 China and Hong Kong, however, have moved away from their roots and are now consuming large amounts of soy beverages -- more than in Europe and the US in fact. Soy protein isolate is more of a Western phenomenon, at least to this point in time, although countries like India are exploring its possibilities as a supplemental protein source for its large, less economically advantaged, vegetarian populace.2

Pretty much all of the data supporting the benefits of soy as a food comes as the result of recent studies promoted by the agricultural industry to justify soy's newfound status as a "healthy alternative" to dairy and meat. It should be taken with a grain of salt -- and I'm not referring to seasoning.

The Benefits of Soy

Current marketing says that soy is rich in protein and other important nutrients and that it makes a valuable contribution to an overall healthy diet. The curious thing is that this marketing comes from both big agribusiness and the health food industry -- strange bedfellows indeed. Nevertheless, there are some studies on the benefits of soy to support their enthusiasm. Soy is high in phytoestrogens -- particularly isoflavones -- which means that it is likely to have a positive hormonal impact on both men and women. And in fact, some studies have shown that consuming soy products can help with menopausal symptoms in women3 and prostate problems in men.4,5 Studies on the benefits of soy in regard to menopausal bone health and the prevention of breast cancer, though, have been more equivocal despite claims to the contrary.

Perhaps unsurprisingly, given that they are (unless adulterated) low in saturated fats and have no cholesterol, the consumption of soy products has been associated with improved cardiovascular health. Specifically, it has been found that diets high in soy products are associated with lower blood pressure,6 reduced triglyceride and cholesterol levels,7 and a reduced incidence of diabetes.8

All of that said, a 2011 report from the North American Menopause Society was far more equivocal in its support of the benefits of soy. According to the report, "From the hundreds of studies reviewed in this report, there are mixed results of the effects on midlife women. Soy-based isoflavones are modestly effective in relieving menopausal symptoms; supplements providing higher proportions of genistein or increased in S(-)-equol may provide more benefits. Soy food consumption is associated with lower risk of breast and endometrial cancer in observational studies. The efficacy of isoflavones on bone has not been proven, and the clinical picture of whether soy has cardiovascular benefits is still evolving. Preliminary findings on cognitive benefit from isoflavone therapy support a "critical window" hypothesis wherein younger postmenopausal women derive more than older women."9 Specifically, the report found that:

  • Soy relieved certain menopausal symptoms. "If you give estrogen a 9 out of 10 score, and placebo 4 of 10, soy would be about 6.5." 
  • "On bone health, we really didn't find adequate evidence to recommend its use for preventing or reducing the risk of osteoporosis and osteoporotic fracture." 
  • Soy's heart health benefit is still evolving in research. 
  • Soy appears to help women under age 65 with cognitive function, but not those over 65. 

Soy as a Protein Source

At one time, soy protein was a waste product -- a byproduct from manufacturing soy oil. Then, in typical American industry brilliance (think fluoride), manufacturers found a way to turn a waste product that cost money to dispose of into a major money maker: they used it as cattle feed.10 And in fact, the use of soy protein as cattle feed is one of the primary driving forces in the growth of the meat and dairy industry. (It's also a major component of feed used to raise chickens, turkeys, pigs, cows, and even fish raised on fish farms.) The next step, obviously, was to make it palatable for human beings. In its raw form, after oil extraction, it looks and smells quite nasty. But by adding flavorings, preservatives, sweeteners, emulsifiers and synthetic nutrients, what was formerly cattle feed is turned into a pretty palatable meat substitute for humans.

Incidentally, soy milk used as a low-fat high-protein dairy substitute has seen the biggest gains in market share. Sales have increased exponentially from $2 million a year in 1980 to approximately $1billion a year today -- and that's just in the US.11

If you consider everywhere it's used (not just by bodybuilders, where whey is king), soy just might be the number one protein supplement on the planet. In fact, according to Margaret E. Cook-Newell, one of the lead researchers in a 1995 review of soy protein published in the New England Journal of Medicine,12 "There are 12,000 soy products on the market, and many more will be coming soon." Seven years later, that number is likely now much, much higher. The bottom line is that, worldwide, the soy protein market currently tops $5.1 billion a year and is projected to just keep on growing as the need for inexpensive protein supplementation only increases as it keeps pace with the world's expanding population and as incomes in third world countries continue to increase.13

The Dangers of Soy

As I mentioned earlier, soy was not used as a food in Asia until fermented soy products appeared. The reason is that soy contains some very powerful nutrient blockers -- bio-chemicals that stop your body from absorbing nutrients found in the soy…or in any other foods that you eat with the soy. There's nothing evil or sinister or even unusual about this. A number of foods contain similar "anti-nutrients." The reasons, at least from the plant's perspective, are simple: first, the plant doesn't want a seed or bean to "activate" until it is in a location suitable for growing; and second, anti-nutrients make plants unappealing to birds and insects. Thus, soy contains enzyme inhibitors and nutrient binders to prevent just that from happening. For most plants, exposure to water is all that is needed to nullify the anti-nutrients. That's why sprouting releases so many nutrients in seeds, and it's why we have to soak most beans overnight before cooking them -- to eliminate the "anti-nutrients." Key anti-nutrients include:

  • Phytates are prevalent in cereal grains and are capable of forming insoluble complexes with calcium, zinc, iron, and other nutrients, thus interfering with their absorption by the body. The soybean has one of the highest phytate levels of any grain or legume, and unlike the phytates in most beans, the phytates in soy are highly resistant to soaking and long, slow cooking. Soy phytate levels, however, can be significantly reduced through a long period of fermentation. Soy milk is very high in phytates, whereas tofu, because of the precipitation process used in its manufacture, falls somewhere in between. People who consume large amounts of soy milk and tofu as their primary protein sources risk severe mineral deficiencies. The results of calcium, magnesium, iron, and zinc deficiency are well known. Diets high in phytic acid can be sufficient by themselves to cause rickets.14 
  • Trypsin inhibitors are proteins found in some raw plant foods (e.g. soybeans) that can inhibit digestion. There are four natural sources of trypsin inhibitors: bovine pancreas, ovomucoid, soybean, and lima bean. Trypsin inhibitors provide unique processes depending on their source. For example, inhibitors in the seeds of legumes (soybean and lima bean) act as a feeding deterrent for insects by disrupting proteases in the small intestine. Big agribusiness is trying to expand on this natural function by using it to develop insect resistant transgenic plants. (Of course, that makes the soy even less useful as a food, but at least crop will be bumper.) Soybean inhibitors have also been found to contribute to pancreatic hypertrophy in rats, again providing a deterrent to rats thinking of feeding on the soy.15  
  • Hemagglutinin is a complex protein that causes other proteins and cells to agglutinate, or clump together. Antibodies and lectins are hemagglutinins that you're probably familiar with. Viruses also make use of hemagglutinins to bind to host cells. Plants such as soy make use of phytohemagglutinins (plant based hemagglutinins) to defend against pests as they cause key cells in the pests, such as blood cells, to clump together. Levels of phytohemagglutinins are high in soy.16 Again, as with the other anti-nutrients, hemagglutinin is deactivated during fermentation.  

Dangers of Soy Protein Isolate and Anti-Nutrients

The process of making soy protein isolates involves acid washes, alkaline baths, and high temperatures and, in fact, gets rid of many but not all of the anti-nutrients. Unfortunately, high temperature processing damages the protein -- it denatures it in a way that makes it harder to break down in the intestinal tract and, ultimately, harder to digest. Understand, certain kinds of denaturing, as provided by stomach acid, unfolds proteins in a way necessary for digestion. Heat, on the other hand, unfolds them in a way that resists digestion.

The bottom line is that even the FDA, in their opinion supporting the use of soy protein isolate, has acknowledged that it must be fortified with extra methionine, lysine, vitamins, and minerals -- either by addition to the soy isolate product, or as provided by other components of the diet.17

Soy Phytoestrogens

I've certainly been a proponent of phytoestrogens over the years as a defense against the petroleum based xenoestrogens that can lead to estrogen dominance. And that hasn't changed. Estrogen dominance can be a factor in all kinds of problems, including:

  • Excess estrogen is the only known cause of endometrial cancer.
  • Increased risk of breast cancer.
  • Loss of bone mass.
  • Increased risk of autoimmune disorders such as lupus.
  • Fibrocystic breasts.
  • Fibroid tumors.
  • Depression and irritability.
  • PMS symptoms such as cramping and bloating -- in addition to depression and irritability.
  • Menopausal symptoms such as hot flashes and night sweats -- again, in addition to depression and irritability.
  • Decreased sex drive.
  • Increased body hair and thinning of scalp hair.
  • Migraine headaches.
  • Impaired thyroid function, including Grave's disease.
  • Increased body fat.
  • Increased blood clotting.
  • Impaired blood sugar control.
  • The astounding acceleration of puberty in young girls from an average age of 14 to 15, to now as young as 9 or 10. (This represents a speed up of as much as 1/3 sooner in their lives and has frightening implications for long term health.) 
  • And, finally, xenoestrogens have been strongly implicated in declining male sperm production and the increase in the rates of testicular cancer and prostate cancer.

Phytoestrogens work primarily by filling the body's estrogen receptor sites with weaker plant based estrogens so that those sites are no longer available to far stronger natural, synthetic, or even petroleum based estrogens. But…. as I have also said many times before. "Too much of a good thing is bad. Too much of any food or supplement is bad. If you over indulge in something, no matter how beneficial it is, it will result in illness, not health." Sun exposure, for example, is important for vitamin D production; but too much sun leads to dried out skin and a higher risk of skin cancer.  Pure water is important. But if you overindulge, it can lead to "water intoxication" and even death.  And fiber is crucial for intestinal health, but consume too much and it can lead to malabsorption of vitamins and minerals and, in some cases, even intestinal blockage. And the same rule applies to phytoestrogens. So how does that relate to soy?

Soy is packed with isoflavones. In fact, many of the benefits of soy consumption are attributed to its high isoflavone content. Isoflavones are polyphenolic compounds that are capable of exerting estrogen-like effects and are thus classified as phytoestrogens (plant-based compounds with estrogenic activity). Soy contains the highest concentration of phytoestrogens of any regularly consumed dietary source known. Specifically, there are three soy isoflavone glycosides: genistin, daidzin, and glycitin. And there are three soy isoflavone aglycones: genistein, daidzein, and glycitein. Studies have shown that these phytoestrogens are likely to be health promoting when taken in reasonable amounts. When taken at very high levels, though, the data is more conflicted. And keep in mind that in the case of children or infants on formula, it doesn't take much soy to pack the body with phytoestrogens on a per pound basis of bodyweight. And that's why studies on children are even more equivocal than those on adults. Some of the concerns associated with high soy intake for adults and children are:

  • Male infertility.18 In studies, male subjects who have the highest soy intake also have the lowest sperm counts compared to men who eat no soy foods.19 In another study, after four weeks of using soy protein powder, the average testosterone levels of adult subjects decreased by 19%.20
  • Abnormal bleeding of the uterus, endometriosis and polyps in women.21
  • Thyroid problems.22 Consumption of as little as two tablespoons of soybeans per day for only one month results in a significant increase in thyroid-stimulating hormone. 
  • Goiter (or goitre).23 Goiters can come and go with the consumption and subsequent stoppage of soy milk.
  • Brain atrophy.24 Poor cognitive test performance, enlargement of ventricles, and low brain weight were each significantly and independently associated with higher midlife tofu consumption. And short term, drinking less than one ounce of soy milk daily may lead to loss of memory.
  • Kidney Stones. Soy contains oxalates, which cannot be metabolized by the body and are excreted through urine. Oxalates bind to calcium in the kidneys, which can lead to the formation of kidney stones, especially if you have a history of kidney stones.

Soy Babies

And any problems with soy, as we've already indicated, are going to be amplified in infants and toddlers for the simple reason that they have lower body weight. The daily exposure of infants to isoflavones in soy formula is six to11 times higher on a body-weight basis than the dose that has hormonal effects in adults consuming soy foods. Total isoflavone concentrations of soy-based formulas prepared for infant feeding range from 32 to 47 thousandths of a gram per liter, whereas isoflavone concentrations in human breast milk are only 5.6 ± 4.4 millionths of a gram per liter.25 This translates as Isoflavone concentrations that are 13,000--22,000-fold higher than plasma estradiol concentrations in breastfed babies in early life. Or another way to look at it is that infants raised on soy formula receive the estrogen equivalent (based on body weight) of some five birth control pills per day. That is an astounding difference!

And it means that all of the effects we've already talked about in adults occur in infants and children, but at an accelerated rate. For example:

  • Goiters.26 
  • Thyroid problems.27 
  • Sexual anarchy. Testosterone levels in infants as high as found in adult males.28 Baby girls showing signs of puberty as early as age three.29 
  • Uterine fibroids. Side effects and long-term health consequences to infants fed soy milk formula containing isoflavones were reported in Environmental Health Perspectives in March 2010. From 50,000 participants involved in a four-year study, findings were that women who were fed soy milk in infancy had a 25 percent higher incidence of uterine fibroids by age 35.30 

Dangers of Soy Allergens

Another factor to consider when looking at soy protein is that there is actually no such thing as "soy protein" or any other "type" of protein, for that matter. Each source of protein is actually a conglomeration of several protein fractions that we lump together under their source name. Dairy protein, for example, actually describes a group of proteins that includes casein (which itself is a conglomeration of alpha caseins 1&2, beta casein, and kappa casein), alpha-lactalbumin, beta-lactoglobulin, and bovine serum albumin. Soy protein, likewise, is a mix of a number of protein fractions, although the names for the soy fractions are more utilitarian than for dairy, more prosaic if you will. Soy protein fractions include: 28 kD, 30-34 kD, 37 kD, 49 kD, and 50 kD. It's not necessary to know the names of all the different protein fractions in the different types of protein, but it is vital to know that they exist. Why? Because the different fractions have different degrees of digestibility and promote different degrees of allergic response. The prime culprit in soy, for example, is most likely 30-kD allergen (Gly m Bd 30).31 Ultimately, the quality of a protein source (and its tendency to cause allergic response) is determined by how your body handles each and every fraction in that source. With at least 16 allergenic proteins (with some estimates as high as 25 to 30), soy ranks as one of the most allergenic proteins in existence.

Mildly allergic people may have itching and a few hives, while those who are severely allergic may experience severe, life-threatening symptoms such as breathing problems or swelling of the throat. But most people fall below those two levels of response -- into the "almost" unnoticeable level.  At this level, symptoms, which may include gas, bloating, and low level irritation of intestinal tissue, are often not even identified at a conscious level and are almost never connected to the soy that causes them. The problem with low level allergic responses does not stem from taking soy occasionally, but if it is used as a regular component of the diet. Then these low level "unconscious" conditions can become chronic illness -- that magically "seems" to appear out of nowhere and for no particular reason.

Soy in the U.S. is Almost All Genetically Modified

The first applications for the development of genetically engineered soy did not even appear until 1987.  By the year 2000, over 50% of all soybeans planted in the U.S. were, according to current terminology, genetically modified organisms (GMO). By 2007, that number had soared to an astounding 91%. It's important to understand that soybeans have not been modified to improve their nutritional value, but rather to improve crop yields.  In fact, one of the primary genetic modifications is to make soybeans "Roundup Ready." Roundup is an herbicide that kills weeds. "Roundup Ready" means that the soy has been genetically modified so that it is unaffected by the herbicide. This allows farmers to spray Roundup to their heart's content to kill weeds, thus increasing farming efficiency. Unfortunately, this means that your soy comes packed with Roundup…and its genetic modification.

And as Dr. Joseph Mercola points out, not only is GM soy linked to an increase in allergies, but "the only published human feeding study on GM foods ever conducted verified that the gene inserted into GM soy transfers into the DNA of our gut bacteria and continues to function. This means that years after you stop eating GM soy, you may still have a potentially allergenic protein continuously being produced in your intestines.32" In other words, if you eat GMO soy, there is a high likelihood that you will be genetically modified too.

Conclusion

The problem is that the benefits of soy are not miraculous. Yes, if you eat small amounts of organic, fermented versions, it actually provides some substantial health benefits. But if consumed as a primary protein source in unfermented forms -- such as soy milk and tofu -- its health and safety values are much more suspect.  The dangers of soy are not overwhelming, but they cannot be ignored. I know there are soy fanatics out there -- even many who read my newsletters -- but if it were me (and it is):

  • I would not consume more than one ounce of soy a day -- if at all. 
  • I would eat only the fermented forms -- tempeh, natto, miso, and "real" soya sauce. 
  • I would absolutely not use soy milk because it is too easy to consume too much soy that way. Personally, I now use almond milk. It's low carb, low fat, and low calorie. On the downside it's also low protein, and if you have a nut allergy, it's undoable. Other options are coconut milk and rice milk -- but I would use those in lesser amounts because of their respective fat content and carb contents. And if you opt for dairy, make sure it's organic, raw, and grass fed --if you can get it. 
  • I would eat only organic soy. I would not touch the GMO version -- although that's getting harder and harder to avoid as many organic soy crops are becoming contaminated as GMO pollen spreads.33 
  • I would not use soy isolate as a protein supplement. As I have said previously, my preference is for a rice/pea protein blend, although 70% hemp protein is emerging as an interesting alternative. I would even use organic, grass fed, cold processed whey before I opted for soy. (Note: although I like rice/pea protein for adults, I would not recommend it for children.) 

Again, if you choose to partake of the benefits of soy, restrict your consumption to small amounts and eat only organically grown fermented products. At least that will provide you a hedge against unignorable soy dangers.

  • 1. Julia R. Barrett. "The Science of Soy: What Do We Really Know?" Environ Health Perspect. 2006 June; 114(6): A352-A358. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1480510/
  • 2. Adam Brinker, Joe Parcell, Chris Boessen. "An Assessment of the India Soy Protein Market." Selected Paper prepared for presentation at the Southern Agricultural Economics Association Annual Meeting, Dallas, TX, February 2-6, 2008. http://ageconsearch.umn.edu/bitstream/6796/2/sp08br07.pdf
  • 3. Taku, Kyoko; Melby, Melissa K.; Kronenberg, et al. "Extracted or synthesized soybean isoflavones reduce menopausal hot flash frequency and severity: systematic review and meta-analysis of randomized controlled trials." Menopause. 19(7):776-790, July 2012. http://journals.lww.com/menopausejournal/Abstract/2012/07000/Extracted_or_synthesized_soybean_isoflavones.11.aspx
  • 4. Yan L, Spitznagel EL. "Soy consumption and prostate cancer risk in men: a revisit of the meta-analysis." Am J Clin Nut. 2009; 89: 1155-63. http://www.ncbi.nlm.nih.gov/pubmed/19211820
  • 5. Hwang YM et al. "Soy food consumption and risk of prostate cancer: a meta-analysis of observational studies." Nutr Cancer. 2009: 61: 598-606. http://www.ncbi.nlm.nih.gov/pubmed/19838933
  • 6. Liu XX, Li SH, Chen JZ, et al. "Effect of soy isoflavones on blood pressure: a meta-analysis of randomized controlled trials." Nutr Metab Cardiovasc Dis. 2012 Jun;22(6):463-70. Epub 2011 Feb 9. http://www.ncbi.nlm.nih.gov/pubmed/21310599
  • 7. Wang Y, Jones PJ, Ausman LM, Lichtenstein AH. "Soy protein reduces triglyceride levels and triglyceride fatty acid fractional synthesis rate in hypercholesterolemic subjects." Atherosclerosis. 2004 Apr;173(2):269-75. http://www.ncbi.nlm.nih.gov/pubmed/15064101
  • 8. Villegas R, Gao YT, Yang G, Li HL, Elasy TA, Zheng W, Shu XO. "Legume and soy food intake and the incidence of type 2 diabetes in the Shanghai Women's Health Study." Am J Clin Nutr. 2008 Jan;87(1):162-7. http://www.ncbi.nlm.nih.gov/pubmed/18175751
  • 9. Clarkson, Thomas B.; Utian, Wulf H.; Barnes, Stephen, et al. "NAMS 2011 Isoflavones Report. The role of soy isoflavones in menopausal health: report of The North American Menopause Society/Wulf H. Utian Translational Science Symposium in Chicago, IL (October 2010)." Menopause: July 2011 - Volume 18 - Issue 7 - pp 732-753. http://journals.lww.com/menopausejournal/Abstract/2011/07000/The_role_of_soy_isoflavones_in_menopausal_health_.5.aspx
  • 10. "How Soybeans are Used." North Carolina Soybean Producers Association, Inc. (Accessed 9 Sept 2012.) http://www.ncsoy.org/ABOUT-SOYBEANS/Uses-of-Soybeans.aspx
  • 11. Choy Leng Yeong. "Dean Says U.S. Soy-Milk Sales May Reach $1 Billion (Update2)." Bloomberg. June 15, 2009. (Accessed 9 Sept 2012.) http://www.bloomberg.com/apps/news?pid=newsarchive&sid=aX1Je8Kr7S6U
  • 12. Anderson JW, Johnstone BM, Cook-Newell ME. "Meta-analysis of the effects of soy protein intake on serum lipids." N Engl J Med. 1995 Aug 3;333(5):276-82. http://www.nejm.org/doi/pdf/10.1056/NEJM199508033330502
  • 13. A Soyatech syndicated research report prospectus. "Soy Proteins 2010." Soyatech. 2010. http://www.soyatech.com/product_documents/49soyproteinreport2011.pdf
  • 14. Wills, M.R. et al., "Phytic Acid and Nutritional Rickets in Immigrants", The Lancet, April 8,1972, pp. 771-773.
  • 15. J. C. Smith,F. D. Wilson, P. V. Allen, D. L. Berry. "Hypertrophy and hyperplasia of the rat pancreas produced by short-term dietary administration of soya-derived protein and soybean trypsin inhibitor." Journal of Applied Toxicology. Volume 9, Issue 3, pages 175--179, June 1989. http://onlinelibrary.wiley.com/doi/10.1002/jat.2550090307/abstract?systemMessage=Wiley+Online+Library+will+be+disrupted+on+15+September+from+10%3A00-12%3A00+BST+%2805%3A00-07%3A00+EDT%29+for+essential+maintenance
  • 16. Irvin E. Liener and Shohachi Wada. "CHEMICAL MODIFICATION OF THE SOY BEAN HEMAGGLUTININ." J. Biol. Chem. 1956 222: 695-704. http://www.jbc.org/content/222/2/695.full.pdf+html
  • 17. Select Committee on GRAS Substances (SCOGS). "Opinion: Soy protein isolate." FDA 1979. http://www.fda.gov/Food/FoodIngredientsPackaging/GenerallyRecognizedasSafeGRAS/GRASSubstancesSCOGSDatabase/ucm261441.htm
  • 18. Chavarro JE, Toth TL, Sadio SM, Hauser R. "Soy food and isoflavone intake in relation to semen quality parameters among men from an infertility clinic." Hum Reprod. 2008 Nov;23(11):2584-90. Epub 2008 Jul 23. http://www.ncbi.nlm.nih.gov/pubmed/18650557
  • 19. "Can phytoestrogens cause infertility?" Arbor Clinical Nutrition Updates, Issue 308:1-3, 30 June 2009.
  • 20. Arbor 2009.
  • 21. Chandrareddy A et al. (2008). Adverse effects of phytoestrogens on reproductive health: a report of three cases. Complement Ther Clin Pract. 14(2):132-5. http://www.ncbi.nlm.nih.gov/pubmed/18396257
  • 22. Ishizuki, Y. et al., "The effects on the thyroid gland of soybeans administered experimentally in healthy subjects", Nippon Naibunpi Gakkai Zasshi (1991) 767:622-629. http://www.ncbi.nlm.nih.gov/pubmed/1868922
  • 23. "Soybean Milk and the Production of Goitre." Can Med Assoc J. 1960 Sep 10;83(11):608. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1938649/pdf/canmedaj00856-0043b.pdf
  • 24. White LR, Petrovitch H, Ross GW, Masaki KH, et al. "Brain aging and midlife tofu consumption." J Am Coll Nutr 2000 Apr;19(2):242-55. http://www.ncbi.nlm.nih.gov/pubmed/10763906
  • 25. Setchell, K.D. et al., "Isoflavone content of infant formulas and the metabolic fate of these early phytoestrogens in early life." American Journal of Clinical Nutrition, December 1998 Supplement, 1453S-1461S. http://ajcn.nutrition.org/content/68/6/1453S.full.pdf
  • 26. Doerge DR, Chang HC. "Inactivation of thyroid peroxidase by soy isoflavones, in vitro and in vivo." J Chromatogr B Analyt Technol Biomed Life Sci. 2002 Sep 25;777(1-2):269-79. http://www.ncbi.nlm.nih.gov/pubmed/12270219
  • 27. Irvine, C. et al. "The Potential Adverse Effects of Soybean Phytoestrogens in Infant Feeding." New Zealand Medical Journal May 24, 1995, p. 318. http://www.ncbi.nlm.nih.gov/pubmed/7783996
  • 28. Sharpe RM, Martin B, Morris K, Greig I, et al. "Infant feeding with soy formula milk: effects on the testis and on blood testosterone levels in marmoset monkeys during the period of neonatal testicular activity." Hum Reprod. 2002 Jul;17(7):1692-703. http://www.ncbi.nlm.nih.gov/pubmed/12093826
  • 29. Herman-Giddens, Marcia E. et al. "Secondary Sexual Characteristics and Menses in Young Girls Seen in Office Practice: A Study from the Pediatric Research in Office Settings Network." Pediatrics 99(4):505-512, April 1997. http://www.ncbi.nlm.nih.gov/pubmed/9093289
  • 30. D'Aloisio AA, Baird DD, DeRoo LA, Sandler DP. "Association of intrauterine and early-life exposures with diagnosis of uterine leiomyomata by 35 years of age in the Sister Study." Environ Health Perspect. 2010 Mar;118(3):375-81. http://www.ncbi.nlm.nih.gov/pubmed/20194067
  • 31. Helm RM, Cockrell G, Connaughton C, Sampson HA, et al. "A Soybean G2 Glycinin Allergen." Int Arch Allergy Immunol 2000;123:205--212. http://www.ncbi.nlm.nih.gov/pubmed/11112856
  • 32. Joseph Mercola. "This "Miracle Health Food" Has Been Linked to Brain Damage and Breast Cancer." Mercola.com 18 Sept 2010. (Accessed 10 Sept 2012.)  http://articles.mercola.com/sites/articles/archive/2010/09/18/soy-can-damage-your-health.aspx
  • 33. "Shipment of organic soybeans tests 20% GMO." The Organic & Non-GMO Report. June 2007. (Accessed 10 Sept 2012.) http://www.non-gmoreport.com/articles/jun07/organic_soybeans.php

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Comments

  •  
    Submitted by Tom on
    September 17, 2012 - 2:29pm

    regarding "Round-Up Ready" GMO version: another reason to go organic, and (for now) non-GMO, is that the soybean plants are practically drenched with the Round-Up chemical to kill off weeds (which leads to Round-Up-tolerant superweeds -- another story), and the chemical itself is taken up by the plant without harm to the plant, and which of course gets into the soybeans themselves. The Round-Up chemical, I understand, will accumulate in human systems -- the body doesn't get rid of it as quickly as we eat it. I don't know exactly what the damages are, studies are underway and results are pending, but as I recall it can definitely wreak havoc with human DNA (cancer, birth defects, etc). Our EPA regards Round-Up as safe and non-toxic to humans, I tend to disregard their work...

  •  
    Submitted by BaselineFoundation on
    September 17, 2012 - 12:02pm

    Virtually, all of the questions you ask are answered in other newsletters and blogs onsite – or even in the newsletter above. For example: in the newsletter above Jon mentions that sprouting nullifies anti-nutrients, but has no effect on phytoestrogens. And here are links to newsletters on protein and enzymes.

    http://www.jonbarron.org/athletic-performance/natural-health-newsletter-protein-1

    http://www.jonbarron.org/enzymes/natural-newsletter-digestive-health-part1

    Search or browse the site. There are thousands of pages of information, not to mention dozens of radio shows and television video interviews with Jon that can keep you busy for days.

  •  
    Submitted by ivan pedro j. schiffer on
    September 18, 2012 - 12:24am

    Salute, Mr. John and his team,

    The analysis is complete. Great work.

    Since long time in my youth my teacher in Macrobiotics in Brazil,Mr. Tomio Kikuchi, used to say, - Soy beans are food for cows, they have four stomachs and regurgitate the ingested food before sending it back to the stomach again to be thoroughly digested.Soy beans are too acidic for humans and undigestible.
    With this very simple explanation I was since then carefull to avoid all the Soy extrudates (made as meat substitutes), or the so called Soy Milk. I had brown rice and sesame milk instead. Sunflower pits milk is also delicious, barley can also be used as well as millet.
    Good quality properly fermented Misso or Soy sauce or Tempeh I believe are very good foods; Misso should be at least 3 years old and had natural ¨KOJI¨(aspergilus rizis) as starter to produce the proper bacterial flora that is similar to the flora in people´s guts and has become alkaline by the fermentation due to time and sea salt activity.

  •  
    Submitted by Jan on
    September 18, 2012 - 3:33am

    I would like to know how this article would relate to the consumption
    of edamame (shelled soy beans) as a vegetable. Is the information (and the names soy bean and edamame)interchangeable?

  •  
    Submitted by BaselineFoundation on
    September 18, 2012 - 12:07pm

    Edamame is certainly an interesting option. In several ways it is quite different from what is known as “field” soy. First of all, it tends to be grown from different varieties than field soy. That means that GMO is not likely an issue when it comes to edamame. And second, it’s a fresh green vegetable as opposed to a mature dried bean.

    Like field soy, edamame contains both phytates and isoflavones, but both at lower levels than field soy – and in the case of isoflavones, markedly so. This means that the phytonutrients in edamame are more bio-available than those found in field soy products. On the other hand, it also means that the phytoestrogen benefits for adults are significantly less.

    Bottom line: edamame is probably both less harmful and less beneficial than soy. When it comes to soy, you’re probably better off opting for the fermented forms.

  •  
    Submitted by Elaine on
    September 18, 2012 - 3:21pm

    I began taking ASU when I learnt about it in your book (gum disease) even though I never eat any form of soy. Brand is distributed by Maximum and shows 300mg, dose 2 capsules a day. In your opinion is this formula OK? Thanks for any answer and great thanks for your book and your newsletters; they are such gifts!

  •  
    Submitted by BaselineFoundation on
    September 18, 2012 - 7:29pm

    As a matter of policy, we do not comment on different companies’ products. There are thousands and thousands and thousands of health products out there. It’s simply impossible for us to keep up – to verify what ingredients each company is using, where they’re sourcing them, and if they are in fact matching their label. With the exception of a few companies that Jon Barron has personal experience with, our actual specific recommendations focus on products from Baseline Nutritionals since Jon actually formulates their products and oversees their ingredient sourcing and manufacturing. (Incidentally, they carry an ASU based product.) For a complete list of Foundation product recommendations, check out: http://www.jonbarron.org/natural-health/program-dietary-supplements-product-recommendations.

    Also, for gum disease, have you checked out Jon’s articles on the role proteolytic enzymes and oil pulling can play in helping eliminate the disease?

    http://www.jonbarron.org/enzymes/proteolytic-dental-health-gum-disease-newsletter

    http://www.jonbarron.org/detox/nl110404/oil-pulling-strong-immunity

  •  
    Submitted by Bob on
    September 16, 2012 - 8:25pm

    You mention your preference for almond milk.

    When my wife and I found out about the possible side effects associated with carrageenan (a thickening agent) in almond milk, we started to buy organic almonds and making our own.

    Jon, what's you take on carrageenan? Should it be avoided?

    Thanks,

    Bob

  •  
    Submitted by Jon Barron on
    September 16, 2012 - 9:22pm

    Carrageenan is a seaweed extract from a particular type of seaweed that is fairly common in the Atlantic Ocean. It is also grown on seaweed farms in Japan. You boil the seaweed to extract the carrageenan. In that sense, carrageenan is "natural" and not much different from how a lot of foods such as tomato paste are made. And yes, there have been a number of rodent studies that have linked carrageenan consumption to intestinal inflammation and a possible increase in bowel disorders, including colon cancer. However, rats and humans (despite how we may feel about some people) are not necessarily the same thing. First, quantities matter. The amounts used in rodent studies tend to be far higher than any human is likely to consume. And second, rats and people respond differently. In fact, one study on how effective animal studies were in identifying drug toxicity found that in only 6 of 114 cases did clinical toxicities have animal correlates.  That’s a 5% correlation! That makes the odds 19:1 that carrageenan does not affect humans in the same way. In support of that, when it comes to carrageenan, no human studies have replicated the results seen in rodent studies. In fact, human studies have shown that the human intestinal tract naturally adapts to carrageenan without compromising the integrity of the intestinal tract. For example: http://www.ncbi.nlm.nih.gov/pubmed/22561171 You also might find the following article interesting: The bottom line on carrageenan is that if consumed in moderation and if you don’t experience any intestinal distress when consuming it, it’s probably pretty benign as food additives go. Obviously, homemade almond milk with nothing added is the better option, but commercial brands with added carrageenan are most likely a safe bet -- safer than soy milk or non-organic commercial dairy anyway.

  •  
    Submitted by Guest on
    September 16, 2012 - 8:40pm

    I'VE BEEN TOLD FOR YEARS THAT THIS WAS BETTER THEN DAIRY MILK AND HAVE JUST STARTED USING IT. I'M GLAD TO SEE THE OTHER SIDE OF THE STORY.WHAT I WANT TO KNOW IS HOW IS THIS PRODUCT"SILK"ALMOND MILK?

  •  
    Submitted by Stephen R. Santangelo on
    September 16, 2012 - 8:55pm

    Wonderful article Jon! Absolutely exquisite. In all my years in the health & fitness business, 1979-present, I have never read anything so well executed.

  •  
    Submitted by Chef Jem on
    September 17, 2012 - 4:06am

    Thanks Stephen and Jon!
    I agree. This is one of the very best articles in this genre. I've already linked several people to it.

  •  
    Submitted by Guest on
    September 16, 2012 - 11:01pm

    1 How does organic/non-gmo sprouted tofu stack up? Does the sprouting process negate any of the negativve effects of soy, like the estrogenic and goitergenic properties?

    2 And i have read differently about the amount of soy consumed in asian cultures. They consume approximately 9-11g of protein from soy a day (approx 1-2 servings max of soy, namely tofu and soy sauce, tempeh, miso). Is this amount ok?

    3 Lastly, tofu is one of the most easy to digest legumes. It is the only legume low in FODMAPs and easily tolerated by those with IBS/IBD. What is ur thought on this and what are come other vegan, easy-to-digest, low-FODMAPs options?

    4 Speaking of protein, is nutritional yeast healthy or harmful? Ive read conflicting reports: some say it is a good source of protein, b12, and other b vitamins. Others say is can cause msg reactions and aggravate dysbiosis. Whats ur take and whats a good amount to have per meal/day, if recommended?

    5 And on the topic of digestion, what are your views on using digestive enzymes: helpful or harmful (harmful because they might lead to dependancy, "lazy" pancreas, un-effective)? In the same token, how do u view probiotics and fermented foods like raw sauerkraut (helpful, useless, or harmful) for cases of dysbiosis and/or overall health?

    6 Finally, what do u think if the optimal way to eat: plant-based/vegan or paleo? Raw vs cooked?

    Thanks

  •  
    Submitted by dorothee on
    September 16, 2012 - 11:48pm

    Thank you for your informative report about soy. So many experts/drs on nutrition have conflicting views it is hard for lay people to know who/what to believe and take the best action for one's (& family)choice of protein.

  •  
    Submitted by Toni on
    September 17, 2012 - 4:50am

    Hi Jon, great article, really making sense of what has been an ongoing controversy. I'd like to know what is your take on Soya Lecithin granules? Are they "safe" as a supplement for lowering cholesterol? They have also been recommended for cognitive function, would you agree or not?

  •  
    Submitted by BaselineFoundation on
    September 17, 2012 - 12:49pm

    In general, soy lecithin is fine. It’s a great source of phosphatidylserine and choline, which are brain nutrients. As an extracted component it pretty much sidesteps 98% of the issues of phytoestrogens and genetic engineering. (A small amount of soy protein usually makes its way into the lecithin granules.) However, moderation is key. People who chronically take more than 3.5 grams of choline per day occasionally have experienced side effects, including low blood pressure, marked by fainting or dizziness. And if you suffer from soy allergies, you may have a problem with soy lecithin.

  •  
    Submitted by Paula Glidden on
    September 17, 2012 - 6:53am

    I have known of the dangers of soy for years. It is, obviously, not all it's cracked up to be. Jon's article is very helpful in describing soy's disadvantages and (rare) advantages, not worth the negatives. My question is this, WHAT is wrong with MEAT, FISH, AND POULTRY?

  •  
    Submitted by BaselineFoundation on
    September 17, 2012 - 10:10am

    Hi Paula,

    You can do a search on our site for each one and read the articles both positive and negative.  Enjoy!

  •  
    Submitted by Guest on
    September 28, 2012 - 11:22am

    Meat, fish and poultry wouldn't work in my tea. I love soy milk in my tea. It's delicious, especially the vanilla flavoured kind. I suppose it's the cane sugar...oops.I always buy organic. Almond and rice milk are too thin for my tea. They make it look like dirty dish water and it's not nearly as tasty. Sometimes I buy organic cow's milk, which tastes pretty good but it's expensive.

    Otherwise, I don't use soy milk and rarely cook with tofu, mainly because I can't make the wonderful dishes that Asians can even though I've tried for years. My concoctions just aren't as flavourful.

    I see that GMO soy is dangerous and have known that for years, but organic soy in small doses is okay.

    Thanks :)

  •  
    Submitted by Jay Patt on
    September 17, 2012 - 9:35am

    Hey Jon: Good article about soy.
    Jay

  •  
    Submitted by Patty on
    September 17, 2012 - 10:14am

    Best article I have read on soy. Thank you!

  •  
    Submitted by Guest on
    September 17, 2012 - 10:22am

    good article but there is more, in extensive studies done by protein technologies years ago they found consumption of 24 grams of soy isolate protein caused an estrogenic effect in males. I won't touch the stuff.

  •  
    Submitted by BaselineFoundation on
    September 17, 2012 - 1:31pm

    Jon did not cover that particular study, but he talked about the estrogenic effects in the newsletter:

    "Male infertility.18 In studies, male subjects who have the highest soy intake also have the lowest sperm counts compared to men who eat no soy foods.19 In another study, after four weeks of using soy protein powder, the average testosterone levels of adult subjects decreased by 19%.20"

  •  
    Submitted by marianne on
    July 1, 2013 - 7:40pm

    Can you pass on some insight regarding how much soy is in phosphatidyl serine? I tried 200mg of the soy free/non-gmo version and find it is no where near as effective as200mg the soy based form which also contains 500mg of PSE Complex (Sharp*PS) I do not believe in any forms of soy for myself except for nattokinase, which i believe is safe because it is from a fermented form.
    I find at age 57, working in the supplement industry, my recall is markedly tested daily. Furthermore, at age 17, I was in a severe MVA which resulted in a coma for 9 days. All is well but things are much better with phosphatidylserine. Family history is also colorful. Mother: Bilateral mastectomies at age 42. Maternal Aunt: breast cancer died at age 31. Aunt's trigger: OC's on and off for several yrs. Mother's trigger (15 yrs post DES)...which left me a DES daughter. No hormones for me! as per a boss who was a pathologist whom I am grateful for that advice. There lies my challenge for fighting my genetic odds. I am 8 yrs post menopause, feel great, but am curious of how dangerous the PSE could be. Any information would be enlightening. Thanking you in advance. m.

  •  
    Submitted by BaselineFoundation on
    July 2, 2013 - 3:11pm

    PS and soy are not the same thing. PS is a phospholipid component that is found in soy and other plant and animal tissue. Chemically, it is identical regardless of its source:C13H24NO10P. The most abundant source of PS is soy lecithin, not the whole soy bean, but the lecithin component. It is also abundant in brain and in organ tissue such as liver and kidney. Only small amounts of PS can be found in dairy products or in plants, with the exception of soy lecithin.

    You have to be careful when using the word “soy” in connection with soy extracts. For example, bioidentical progesterone is now made from soy. But it is pharmaceutically pure. There is no identifiable soy left in it. People who worry about it coming from soy are missing the point. Likewise, nattokinase. Nattokinase is an enzyme produced through the fermentation of soy. The enzyme is not soy and does not even exist in raw soy. By the time the nattokinase is isolated and put into a capsule, there is virtually no identifiable soy left in it.

    PS is slightly different, though. You never really get pure PS. Depending on purity, the non-PS components can range from 15-80%. And therein lies the answer to your question. The effectiveness of the supplement you get has less to do with its source and more to do with its purity. Similar purities should perform similarly, regardless of source.

  •  
    Submitted by Kenzie A. on
    September 10, 2013 - 11:32am

    The Herbalife meal replacement shakes are becoming very popular around my area. I've been trying to do more research on them, I know they're soy based. What is your take on them?

  •  
    Submitted by BaselineFoundation on
    September 11, 2013 - 12:25pm

    Jon typically does not do product reviews, but anything soy based is not recommended, as Jon discusses in this article.

  •  
    Submitted by Sora on
    May 30, 2014 - 4:45pm

    There is a long history of eating soy beans in Japan. Tofu is supposedly have come from China, and there is a documentation of Tofu in 1183 in Japan--this is a verifiable fact. Asia does have a long history of consuming soy beans in a healthy way. We are always surrounded by soy products and eat soy beans in many ways but have not had any problem. To us, consuming Western type of food such as too much meat have created health problems.

  •  
    Submitted by P Bowen on
    September 15, 2014 - 7:13am

    I am a 53 year old female who had soy milk as an infant until age 3. I was told recently all the negative effects of soy and started to worry. I have been reading numbers articles the last few weeks and have come to the conclusion it is another "fad scare" as so many others in the past. To back my statement, every harmful effect stated is the opposite for me. I was one of the last girls to start my period at school ( age 13.5) I do not have any male characteristics, masculinity, etc. ( I am petite. I have been a cheerleader from 5th grade to college, and repeat, very feminine!) I have not had bad, hurtful periods, in fact, less painful than friends/roommates. I have had no cancer, or signs. No fibroid tumors. I have no cognitive impairment. I am a successful college graduate that has always ranked high in my classes. I have very thick hair, even at 53, no migraines, no goiters, and having 2 sisters that are overweight and fight depression… I on the other hand am the one that is active, I am of average weight , and have no depression issues. ( They were NOT fed soy… only me) So if you would like to use me as an example, I having been fed MoySoy till age 3 do not fit your description of a "Soy fed Baby"

  •  
    Submitted by BaselineFoundation on
    September 15, 2014 - 6:23pm

    As Jon points out in his book Lessons from the Miracle Doctors, it’s always problematic generalizing conclusions based on a single example. If you look long enough, you will find the example of the 90 year old man who smokes and drinks heavily every day of his adult life and doesn’t die of a heart attack or cancer—but by being shot by a jealous husband who finds the old man in bed with his 20 year old wife. (By the way, Hugh Hefner doesn’t miss that mark by very much.) That doesn’t mean that smoking and drinking are safe—merely that you found someone outside the trend line.

    The bottom line is that for the vast majority of babies being formula fed compromises health versus being breast fed. Numerous studies have shown that to be true.

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