Soy products are by no means as safe or nutritious as their proponents would have us believe. Then again, the dangers of soy are nowhere near as pronounced as many of its detractors claim. A great deal depends on which soy products you use, and how much.
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. Soy 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).
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
- Protein Source.
- High in phytoestrogens such as isoflavones. These tend to have a positive hormonal impact on both men and women.
- Soy can help women with menopausal symptoms.
- Soy can help with symptoms of osteoporosis.
- Soy can help prevent breast cancer.
- Soy can help men with prostate problems.
The Dangers of Soy
- Unhealthful Protein Source. 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 predators such as birds and insects. 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."
The agricultural industry solved the problem of anti-nutrients by creating soy protein isolates. Soy protein isolates are a highly refined or purified form of soy. The process of making soy protein isolates involves acid washes, alkaline baths, and high temperatures. This 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 digest. Certain kinds of denaturing, such as 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.
- Too much Phytoestrogens. 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. 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.Symptoms of too many phytoestrogens include:
- Male infertility.
- Abnormal bleeding of the uterus, endometriosis and polyps in women.
- Thyroid problems.
- Brain atrophy.
- Kidney Stones.
- Increased risk of breast cancer.
- Loss of bone mass.
- Acceleration of puberty for young girls.
- Increased risk of autoimmune disorders such as lupus.
- 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. Soy protein, likewise, is a mix of a number of protein fractions. 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. Symptoms of a soy allergy include:
– itching and hives
– breathing problems or swelling of the throat
– gas, bloating, IBS or IBD
– depression, anxiety
– chronic illness such as Crohn's disease, Ulcerative Colititis
- Genetically Modified Soy. 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.
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 was 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.
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 soy dangers.
Article excerpted from Jon Barron, Baseline of Health Foundation, September 17, 2012.