Dr. Mercola March 27 2008 57,381 views
Two new studies have shown that fermenting soy dramatically reduces its potential allergenicity, and also increases the number of essential amino acids in soy products.
When soy products were fermented, immunoreactivity was reduced by as much as 99 percent, according to tests that compared the blood plasma reactions for both fermented and unfermented soy products.
Fermentation had also improved the essential amino acid composition in the soy products and produced new peptides that may be beneficial. This was attributed to partial digestion of large soybean peptides by enzymes secreted by the microorganisms used in fermentation.
Whether or not soy is healthy for you is a hotly debated issue. The debate stems largely from the fact that health benefits of fermented soy have been misconstrued as being applicable to nonfermented soy as well, which is simply not the case.
How a Fact Became a Lie
Fermented soybeans have been a tradition in Japanese cuisine for more than 1,000 years. The nutritive value of natto, for example, was so high that Samurai consumed it daily, and even fed it to their horses to increase their speed and strength.
Nonfermented soy products, on the other hand, are NOT health foods, even though manufacturers of soy products have been allowed to label them “heart healthy” since 1999. The “health benefits” of nonfermented soy were simply created through slick marketing by the edible oil industry in the US; invented to create a profitable market for the otherwise unusable byproducts of the soybean oil industry.
The deceptive heart health claim originated from the low rates of heart disease and certain cancers seen in East Asian populations. However, in reality, Asians do not consume nearly as much soy as has been generally assumed, and what they do eat has been fermented for long periods.
What’s Wrong With Nonfermented Soy?
Nonfermented soy products contain phytic acid, which has anti-nutritive properties. Phytic acid binds with certain nutrients, such as iron, to inhibit their absorption. This is a direct, physical effect that takes place in your digestive system. They’ve also been found to contain toxins and disruptive plant estrogens that can damage your thyroid.
Most processed, nonfermented soy products also contain added flavorings, preservatives, sweeteners, emulsifiers and synthetic nutrients – a far cry from what you get after the traditional fermentation process that ancient cultures put their soy through before they would eat it.
As a result of modern processing, most of today’s soy foods are chockfull of anti-nutrients that have been linked to:
It’s actually the fermenting process itself that turns an otherwise inedible food into something quite nutritious.
Soy’s Health Benefits ONLY Apply to Fermented Soy!
As often as I’ve warned against nonfermented soy, such as fresh or dry whole soybeans, soy nuts, soy milk and tofu, I’ve also extolled the wonderful health benefits of traditionally fermented foods, and fermented soy is part of that pack.
After a long fermentation process, the phytic acid and antinutrient levels of the soybeans are reduced, and their beneficial properties – such as the creation of natural probiotics -- become available to your digestive system.
It also greatly reduces the levels of dangerous isoflavones, which are similar to estrogen in their chemical structure, and can interfere with the action of your own estrogen production.
So if you want to take advantage of the health benefits of soy, go ahead! Just make sure you’re eating the fermented varieties and avoid all nonfermented soy products.
Healthy options include:
To SOY or not to SOY- that is the question...
Thanks FER MENTioning the SAUCE of SOY many cons!
Therefore may we co-MISOrate and not lose our TEMPEHr with the inerNATTOnal cartels of fads...
Surely truth is worth PHYTIC about!
Yes, Jo Bee, TOFU-lishly believe all the media hype is a great mistake! Besides, this is NATTO mother's soybean!
Shall we award Jo Bee The Punster Medal of Honor?
You know, there is one more type of fermented soy. Stinky Tofu is what it is called and it STINKS. Most think it is horrid but in some countries they eat a lot of it. It sits in vats with "special sauce" for weeks before they serve it. I think it might possibly be good for you but is so horrible no one wants to go near it.
I think one of the huge misconceptions is that people equate "Asian" to "Japanese" and nothing could be farther from the truth. The Japanese constitute a small percentage of Asians. And we are talking about natto here, which is mostly eaten by the Japanese. I live in Japan and the Japanese eat a lot of soy products including "a lot" of tofu, which is not fermented. I agree about Silk; the Japanese have never heard of it and if they drink soy milk, it is raw. The Japanese eat a lot more than 2 teaspoons of soy a day, and it is definitely not all fermented.
Please people, Asia is a huge place with many varied cultures. Do not talk about a Japanese subject as if it is related to all of Asia. Maybe it's time to study up on all of the very different Asian cultures and learn the differences between them.
ghill is correct about the Japanese eating a lot of soy. Tofu has long been a part of their diet, though the amount varies. (I think it accounts for certain characteristics of their culture.) Otherwise they are mostly eating fermented soy, in the form of soy sauce, miso and natto. Soy milk is not a traditional food, but has been hyped in Japan in recent years. However, it accounts for at most 10% of the dairy section at supermarkets. It is not consumed raw and most of it is sweetened. Soy milk is produced by pureeing the beans, then boiling them and filtering off the fiber, which is also consumed in small amounts. I've seen the health-food hype in Japan a few times (and fallen for it once) saying the women should eat large amounts of non-fermented soy to prevent osteoporosis. I wound up with a severe hormonal imbalance and false menopause. Recently women were told by a popular TV health program that soy would help them lose weight, but this was swiftly and embarrassingly debunked almost immediately. I've also seen in the past couple of years guidelines to doctors urging them to recommend limitation of non-fermented soy consumption. The media have been mum on this.
I cannot comment on soy consumption in other Asian countries, as I haven't lived elsewhere in Asia, but ghill is right about differences. The cuisine differs so strongly as to be mutually unrecognizable. My impression is that only small amounts are used elsewhere, with possible exceptions among the religious.
Very good, Patty. Thanks for the analysis contrasting the phyoestrogen and xenoestrogen.
I would also like to add from my knowledge of Korean culture that traditionally a fair amount of tofu is consumed. I don't think it is near the amount Americans assume "Asians" eat, though.
I guess my asian friends are all unusual since they consume large amounts of tofu (bean curd) on regualr basis.
Feed it to pigs & cows. Then eat venison.
Nealthynut