The soy bean… Part of the legume family, it is a perfect plant that provides humans with the protein they need without the use of animal products. Soy crops outnumbered wheat crops in this country by 1.3 billion (yes BILLION) bushels, and if you are influenced by what the media is feeding us, you might think that soy is a wonder-food, curing cancer, lowering your cholesterol, and eliminating menopausal symptoms.
But while there is a lot of information out there, there is a lot of mis-information, and dare I say… manipulated information, as well. Let’s break it down, shall we?
What is soy?
The soy plant produces beans. These soybeans contain the perfect protein. There are few plants on earth that are sources of “complete proteins”, that is, the kind of protein that provides the essential amino acids that your body needs to build cells. It can replace animal protein in the diet and for this reason, and is usually the protein of choice for vegans and vegetarians.
According to the US Food and Drug Administration:
Soy protein products can be good substitutes for animal products because, unlike some other beans, soy offers a ‘complete’ protein profile. … Soy protein products can replace animal-based foods—which also have complete proteins but tend to contain more fat, especially saturated fat—without requiring major adjustments elsewhere in the diet.
The soy bean can be modified to get a particular product for a particular use….like soy flour, soy milk, tempeh or tofu.
Recent benefits noted
Soy has gotten some press recently when the US Food and Drug Administration allowed package labeling to include the phrase “contains soy that has been shown to lower cholesterol and reduce heart disease”. There were enough studies done that concluded that eating 25 g of soy products daily can lower cholesterol. That, in turn, reduces the incidence of heart disease. This pertains to eating the whole soy protein, and not taking pills or powder that contain soy sub-parts as in protein drinks and energy bars.
In pre-menopausal women, soy (specifically the isoflavone genistein, which is a phytoestrogen) can prevent breast cancer, and in men, can prevent prostate cancer. Studies are underway to look at prevention of osteoporosis, and colon cancer as well. Reduction in risk of breast cancer can be as much as 50%! But these studies looked at whole soy protein intake. Not soy protein particles called isolates.
Here are some ways you might see soy listed:
- soya, soja, soybeans, soyabeans
- textured soy flour
Good soy , bad soy
There is some controversy as to whether the whole soy (found in soy beans and soy flour) is the same as the fractionated soy (found in processed products and labeled as “soy protein isolates” or “hydrolyzed soy protein”).
There is strong evidence that “hydrolyzing” the soy renders it useless, and some say harmful, in giving you all the benefits of the soy plant and is functionally close to evil MSG. When I did research for my article on MSG, the evidence was pretty compelling, and I am now limiting my intake of hydrolyzed and isolate proteins.
Companies that manufacture “high protein” processed foods also use soy to increase the amount of protein in their product. Because soybeans and soy products are very stable, they can be incorporated in many products to have a great shelf-life. But the soy that goes into manufactured foods are hydrolyzed or isolated by breaking down the whole soy and re-assembling it into a product that the body does not recognize as “soy”.
Processed soy derivatives are in most foods you are already eating. Processed soy products can be found in everything from hot chocolate to peanut butter. Any food that has the words “high in protein” on the package probably has processed soy products in them.
Here are some ways you might find processed soy in your foods.
- Hydrolyzed plant protein (HPP)
- hydrolyzed soy protein (HSP)
- hydrolyzed vegetable protein (HVP)
- Lecithin and soy lecithin
- soy protein or textured soy protein (TSP)
- soy protein isolate or soy isolate
- vegetable protein or textured vegetable protein (TVP)
- natural flavor
There are also some studies that look at the effect of other soy subparts–specifically the isoflavones phytoestrogen and genistein (the hormone-like sub parts of soy). In one study, rats were given high doses of the soy isoflavones. The breast tissue in the male rats that ingested high doses of these components of soy developed hyperplasia–a thickening of mammary glands that can sometimes lead to cancer–but didn’t in these rats. With hyperplasia, the tissue is thickened, but not over produced. (so, no…the rats didn’t develop he-teets) This lead some to conclude that if the fractionated soy caused male rats to develop breast tissue, the same would be true for boys (and girls) drinking soy milk.
This study would be similar to if you took carrots, which are obviously healthy when eaten whole, and pulled out all the vitamin A, and hit rats with super-mega doses of it. Vitamin A is healthy when consumed in foods, but an excess of pure Vitamin A is lethal. One could conclude that because the mega-dose of Vitamin A killed the rats, carrots are lethal as well. This just does not make good sense.
When this study hit the mainstream media last year, the data was reported to the effect that soy can lead to breast enlargement in men and boys…..it sure got the male readers attention, and the attention of the moms of baby boys.
But again, the study was done using soy sub-parts, not the whole natural soy as found in soy beans and fermented products like tempeh. So is this study valid for all soy products? It’s unlikely.
Some have taken this news and run with it–a preacher for one–who claims that the increased soy in our diets is “making our kids gay”. (Get this man some education!–and a forehead reduction STAT!)
Soy formula has been gaining popularity in past decades, and with it, some concern over the phytoestrogens in them. However, a 2009 report by the Canadian Pediatric Society states that there have been no adverse reactions or negative effects from the use of soy formula in babies–male or female–and there is no need for avoidance. They cite, again, that the whole form of soy, (that is the whole protein) when consumed, is safe and beneficial, and can provide the necessary form of protein need by infants to develop normally. But they also cite that soy formula should be only be a last resort when feed you baby because a lot of the soy in formula comes in the form of fractionated soy proteins…the ones that are similar to MSG.
Of note is the potential harm of GMO soy, or genetically modified soy. Genetically modified means that the soy plants have been altered in their DNA to grow faster, better, and bigger for increased production. Modern science doesn’t know if these chemically enhanced plants can get into our systems and affect our bodies. Soy and corn made up 82% of all GMO harvested foods in the world. When buying soy products, you should always look for organic. This ensures that the soy is non-GMO. GMO foods are also bred to withstand more pesticide bombardment. Since most soy is GMO (unless otherwise stead) you can bet that it contains extra pesticides.
There is also evidence that soy can interfere with thyroid hormone replacement medications and they should not be taken together to ensure proper absorption. But you can take them several hours apart to avoid any issue. Soy does not cause thyroid problems but can worsen symptoms in those with low iodine.
The “Down with Soy” groups
There are specific groups that have made it their cause to ban soy products from the market and try to feed us with false information to scare us into avoiding soy.
One of these groups is the Weston A Price Foundation. This is a group which follows the teachings of a dentist, Dr Price. (um..a dentist….) The group advocates eating foods that are locally grown, and organic. They advocate eating minimally processed foods and support local farming. (sounds good so far, right?)
But they also are proponents of eating diets high in animal fats, specifically high in saturated fats and cholesterol, and drinking raw milk. They believe that one can only achieve true health through eating meat, organ meats, and whole dairy products …and plenty of them. They have a very active lobbying effort to ban soy formula worldwide and have a very active internet campaign to “educate the public on the dangers and the dark side of soy”. It’s unclear whether they mean all soy? or just the hydrolyzed kind.
It’s no big surprise that the foundation’s biggest “sponsors” when they have conferences are big names in the dairy and grass-fed beef industry. And it doesn’t matter that Dr Price’s “research” has been labeled “misguided” by many critics.
You can check out their interesting website here. You may want to jot down the recipe for Poached Veal Brain with Brown Butter Capers. …mmmmm…got brains? (just for info, this recipe contains 751 cal per serving with 70 g fat 33 g saturated fat….that’s over the amount slated for a whole day’s intake…., 3748 mg cholesterol….over 10 times the amount one should have in a day….. and 616 mg sodium)
Needless to say, if you find a site that states soy is poison, check to see who owns the site before you take the information to heart.
Too much of a good thing?
There is a phenomenon in our culture that when we hear that something is good for us, we overdose on it! This is true for soy as well.
While it is true that soy can be beneficial and a useful part of a healthy diet, it is not a cure-all. Soy should be used to enhance an already healthy diet of vegetables, fruits, and simple whole grains without processed foods (that includes limiting processed soy products like soy “lunch meats”). Soy products provide complete protein sources and can be used in many ways. But read your labels to see if the soy you’re eating is whole or processed.
What about soy milk?
Soy milk is a processed food, and while it is a soy food, it also contains other additives that may not be healthy like carageenan and flavorings. One serving of soy protein is contained in only 3 ounces of soy milk. You can see how if you are drinking 8-12 ounce glasses of soy milk that you would be getting much more soy that you should be getting in one day. Soy milk is not a “whole food”, that is, unprocessed. Tofu is the same as it is processed, but can be used in moderation. 1/5 of a brick of tofu is a serving size. Tempeh, miso and natto asre excellent forms of soy as they are fermented and provide additional healthy bacteria for your gut which can increase immunity. Natto also contains Vitamin K2, a powerful vitamin that helps calcium build bone and Vitamin D get to the right place.
Soy for breast cancer survivors
A new study with over 9000 participants showed that breast cancer survivors who ate 1-2 servings of whole soy had a 25% reduction in breast cancer recurrence! That’ huge!!Am J ClinNutr. 2012 Jul;96(1):123-32
The bottom line
- Processed foods that contain “soy protein”, “soy isolate”, or “hydrolyzed soy protein” are not the healthy form of soy and should be avoided.
- whole soy contains phytoestrogen genistein, which can affect hormone receptors, but are not activated hormones, so while they may protect from hormone based cancer (breast, prostate) they cannot make boys develop breasts.
- the nutritional benefits of whole soy has been studied and has been found to be a good source of complete protein as part of a healthy diet when used in moderation.
- whole soy can help lower cholesterol when used as part of a low-fat diet rich in vegetables, fruits and whole grains
- one serving of whole soy per day is enough (1/2 cup edamame…3 ounces of tempeh)
- soy in its whole form is safe for everyone of both sexes when consumed in the proper amounts
- use organic soy products whenever possible to avoid GMO soy
- premenopausal women/men can reduce their risk of breast cancer/prostate cancer by eating one serving of soy/day
- women with a history of breast cancer can reduce their risk of recurrence by 25% from eating a diet that includes 1-2 servings of soy daily. Am J Clin Nutr. 2012 Jul;96(1):123-32
I welcome your thoughts!