Myths & Truths About Soy
Myth: Use of soy as a food dates back many thousands of years.
Truth: Soy was first used as a food during the late Chou dynasty (1134-246 BC), only after the Chinese learned to ferment soy beans to make foods like tempeh, natto and tamari.
Myth: Asians consume large amounts of soy foods.
Truth: Average consumption of soy foods in Japan and China is 10 grams (about 2 teaspoons) per day. Asians consume soy foods in small amounts as a condiment, and not as a replacement for animal foods.
Myth: Modern soy foods confer the same health benefits as traditionally fermented soy foods.
Truth: Most modern soy foods are not fermented to neutralize toxins in soybeans, and are processed in a way that denatures proteins and increases levels of carcinogens.
Myth: Soy foods provide complete protein.
Truth: Like all legumes, soy beans are deficient in sulfur-containing amino acids methionine and cystine. In addition, modern processing denatures fragile lysine.
Myth: Fermented soy foods can provide vitamin B12 in vegetarian diets.
Truth: The compound that resembles vitamin B12 in soy cannot be used by the human body; in fact, soy foods cause the body to require more B12
Myth: Soy formula is safe for infants.
Truth: Soy foods contain trypsin inhibitors that inhibit protein digestion and affect pancreatic function. In test animals, diets high in trypsin inhibitors led to stunted growth and pancreatic disorders. Soy foods increase the body’s requirement for vitamin D, needed for strong bones and normal growth. Phytic acid in soy foods results in reduced bioavailabilty of iron and zinc which are required for the health and development of the brain and nervous system. Soy also lacks cholesterol, likewise essential for the development of the brain and nervous system. Megadoses of phytoestrogens in soy formula have been implicated in the current trend toward increasingly premature sexual development in girls and delayed or retarded sexual development in boys.
Myth: Soy foods can prevent osteoporosis.
Truth: Soy foods can cause deficiencies in calcium and vitamin D, both needed for healthy bones. Calcium from bone broths and vitamin D from seafood, lard and organ meats prevent osteoporosis in Asian countries—not soy foods.
Myth: Modern soy foods protect against many types of cancer.
Truth: A British government report concluded that there is little evidence that soy foods protect against breast cancer or any other forms of cancer. In fact, soy foods may result in an increased risk of cancer.
Myth: Soy foods protect against heart disease.
Truth: In some people, consumption of soy foods will lower cholesterol, but there is no evidence that lowering cholesterol improves one’s risk of having heart disease.
Myth: Soy estrogens (isoflavones) are good for you.
Truth: Soy isoflavones are phyto-endocrine disrupters. At dietary levels, they can prevent ovulation and stimulate the growth of cancer cells. Eating as little as 30 grams (about 4 tablespoons) of soy per day can result in hypothyroidism with symptoms of lethargy, constipation, weight gain and fatigue.
Myth: Soy foods are safe and beneficial for women to use in their postmenopausal years.
Truth: Soy foods can stimulate the growth of estrogen-dependent tumors and cause thyroid problems. Low thyroid function is associated with difficulties in menopause.
Myth: Phytoestrogens in soy foods can enhance mental ability.
Truth: A recent study found that women with the highest levels of estrogen in their blood had the lowest levels of cognitive function; In Japanese Americans tofu consumption in mid-life is associated with the occurrence of Alzheimer’s disease in later life.
Myth: Soy isoflavones and soy protein isolate have GRAS (Generally Recognized as Safe) status.
Truth: Archer Daniels Midland (ADM) recently withdrew its application to the FDA for GRAS status for soy isoflavones following an outpouring of protest from the scientific community. The FDA never approved GRAS status for soy protein isolate because of concern regarding the presence of toxins and carcinogens in processed soy.
Myth: Soy foods are good for your sex life.
Truth: Numerous animal studies show that soy foods cause infertility in animals. Soy consumption enhances hair growth in middle-aged men, indicating lowered testosterone levels. Japanese housewives feed tofu to their husbands frequently when they want to reduce his virility.
Myth: Soy beans are good for the environment.
Truth: Most soy beans grown in the US are genetically engineered to allow farmers to use large amounts of herbicides.
Myth: Soy beans are good for developing nations.
Truth: In third world countries, soybeans replace traditional crops and transfer the value-added of processing from the local population to multinational corporations.
Soy Infant Formula: Birth Control Pills for Babies
Babies fed soy-based formula have 13,000 to 22,000 times more estrogen compounds in their blood than babies fed milk-based formula. Infants exclusively fed soy formula receive the estrogenic equivalent (based on body weight) of at least five birth control pills per day.
Male infants undergo a “testosterone surge” during the first few months of life, when testosterone levels may be as high as those of an adult male. During this period, baby boys are programmed to express male characteristics after puberty, not only in the development of their sexual organs and other masculine physical traits, but also in setting patterns in the brain characteristic of male behavior.
In animals, soy feeding indicates that phytoestrogens in soy are powerful endocrine disrupters. Soy infant feeding reduces testosterone levels in male marmoset monkeys as much as 70% and cannot be ignored as a possible cause of disrupted development patterns in boys, including learning disabilities and attention deficit disorder. Male children exposed to DES, a synthetic estrogen, had testes smaller than normal on maturation.
Almost 15 percent of white girls and 50 percent of African-American girls show signs of puberty, such as breast development and pubic hair, before the age of eight. Some girls are showing sexual development before the age of three. Premature development of girls has been linked to the use of soy formula and exposure to environmental estrogen-mimickers such as PCBs and DDE.
Animal studies indicate that consumption of more than minimal amounts of phytoestrogens during pregnancy may have adverse affects on the developing fetus, the timing of puberty later in life, and thinking and behavior patterns, especially in male offspring.
For a full list of references and further information on the dangers of modern soy products visit our Soy Alert! section or go to www.soyonlineservice.co.nz.
Confused About Soy?–Soy Dangers Summarized
- High levels of phytic acid in soy reduce assimilation of calcium, magnesium, copper, iron and zinc. Phytic acid in soy is not neutralized by ordinary preparation methods such as soaking, sprouting and long, slow cooking. High phytate diets have caused growth problems in children.
- Trypsin inhibitors in soy interfere with protein digestion and may cause pancreatic disorders. In test animals soy containing trypsin inhibitors caused stunted growth.
- Soy phytoestrogens disrupt endocrine function and have the potential to cause infertility and to promote breast cancer in adult women.
- Soy phytoestrogens are potent antithyroid agents that cause hypothyroidism and may cause thyroid cancer. In infants, consumption of soy formula has been linked to autoimmune thyroid disease.
- Vitamin B12 analogs in soy are not absorbed and actually increase the body’s requirement for B12.
- Soy foods increase the body’s requirement for vitamin D.
- Fragile proteins are denatured during high temperature processing to make soy protein isolate and textured vegetable protein.
- Processing of soy protein results in the formation of toxic lysinoalanine and highly carcinogenic nitrosamines.
- Free glutamic acid or MSG, a potent neurotoxin, is formed during soy food processing and additional amounts are added to many soy foods.
- Soy foods contain high levels of aluminum which is toxic to the nervous system and the kidneys.
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Hi there, I have a question about fermented soy foods in relation to amenorrhea. I’ve read that phytoestrogens in soy can make the body believe it has enough/surplus estrogen so that it stops producing estrogen, which disrupts menstrual cycles. I’ve struggled with amenorrhea for a long time, and I eat tofu occasionally, but most often the only soy I consume is tempeh anywhere from one to four times a week. Can you explain the effect of fermentation, if any, on phytoestrogenic properties of soy? Should I be wary of consuming organic fermented tempeh if I hope to gain a menstrual cycle? Thank you!
There was a time 3 years ago when I was eating tempeh once a week for a couple months, because I was eating out with a vegetarian boyfriend. During and just following those months, my hormonal symptoms were outrageously uncomfortable and annoying. Periods that dragged on forever, intensely, unbearably sore breasts, moody/weepy, PMS up the yin yang…not doing that again! And that was fermented soy…and even that seemed to have an intense hormonal effect upon me, unlike my usual experiences. At first I thought it was just perimenopause symptoms, but they stopped when I stopped the regular tempeh, although perimenopause has continued on, albeit profoundly better without the soy.
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I joined herbalife some years ago and quickly left when I discovered that soy was not a healthy option for protein intake. You have obviously researched the same sites I have and more by the looks of it. I am really happy you have spread the word about the dangers of soy. There are some counties in England (I am from Scotland) where they only have access exclusively to baby soy formulas. This makes me really F***ing angry. Sorry but I feel so stronly about this. I have family down there. I don’t know if its the same case today but at the time I was hearing there health issues such as obesity and delayed learning for pre school children. Constipation and all manner of problems associated with the SMA baby milk formula.I’m sure its SMA? Thank you for spreading the word.
Does anyone think young girls growing up eating soy/tofu/soy fake meats are more likely to have earlier ages for start of their menstrual cycle and boobs on the larger side? Could anyone connect that to soy in their diet rather than just genetics alone?
Could it be related to heavy periods/bad cramps?
Also, could a substantial amount of soy in the diet have contributed to uterine fibroids that had to be removed by surgery?
Have any researchers explored any of these female specific issues? Has anyone else seen these things in their family members or themselves and wondered if related to diet rich in soy? Because I remember when suddenly soy and vegetarians because big in like the 90s I guess and my family jumped on that wholeheartedly and I have sill come across old cookbooks, magazines and articles singing the praises of soy… Ugh. What’s worse is I love tofu teriaki, sigh, I like salmon too, yeah, but I miss it with tofu. But I have family members still eating it regularly. 🙁
An 86-year-old woman had a lumpectomy on one breast 18 years ago, thereafter sought to abstain totally from all foods containing soy, but subsequently, after eating one portion containing soy, developed a new lump in the same breast and had it removed. She believes that this second occasion of breast cancer was caused by that one dietary slip. What are the scientific considerations that either support or rule out that concern?
I’m not confused about soy, however there is so much on the internet praising the benefits of genistein. There is even a supplement. I’ve been aware of the dangers of soy since the 80s.
I am confused though as to why there is all this “fabulous” benefits of soy information. Is it the industry pushing it or have there been new discoveries? I feel I’m being naive about this. Hopefully someone can help me understand what the heck is going on.
If you know the truth about everything we’ve been told about nutrition that I’ve learned (they lie about red meat, lie about eggs, lie about saturated fat, lie about cholesterol, lie about salt, lie about raw milk, lie about animal foods in general, lie about canola oil (all seed oils), lie about flouride (neurotoxin) added to our water, lie about GMO’s, lie about lab-grown meat….and it goes on and on and on and on. The only conclusion is that it is intentional. So that’s the way I lean re soy. They never deviate and come full circle w/the truth which is why it’s so confusing and why we know it’s not about our health. There are so many testimonials of people, curing their chronic health illnesses and going of their pharmaceuticals when doing the opposite than the USDA nutritional guidelines.
I feel the same way you do, that it must be intentional. Studies being skewed or ignored. It’s very alarming.
What about Organic soy, tofu? Is it still dangerous or are all these ‘dangers’ regarding GMO soy that is also covered in Glyphosate? Sure processed foods mostly contain GMO soy.
I watch A Lot of Japanese television, real life shows, they seem to consume considerable amounts of soy, not just as condiments.
Hi!
I have a question about feeding soy as animal feed.
I have been avoiding feeding soy in any form to cows, ducks, & pigs. Soy has an unsurpassed amount of protein however, as compared to Field Peas, and I have heard that if soy is roasted, or fermented, the downsides of soy can be neutralized.
Has any research been done on this? If we were to roast the soybeans, or ferment them in buttermilk before feeding, would this make feeding Non GMO / Organic soy to animals acceptable?
Does soy lecithin contain phytoestrogens?