Thursday 21 April 2011

Why Soy is Fermented in Korea and Asia

At lunch, I skipped the tofu. A friend asked me why I didn't eat my tofu the other day. I told him I didn't eat it because I had a bad experience with it.  He said something along the lines like that's rubbish.

I understand his sentiment. And to be fair, I wasn't being clear at the moment. I eat tofu, just I didn't feel like any.  Soy is being marketed as a miracle food and it seems so innocuous and cruelty free. But from my previous experience of eating tofu in large quantities, the way it is traditionally consumed in Asian, and the studies down on soy, I think and feel differently.

First of all, Soy is not bad. It's just that soy is eaten and prepared in a way people in the west don't normally follow. I oversimplify a lot of what follows this and even don't list all the negatives because there are some more. But generally what I stress is a model of eating that needs to be considered as a whole and not considered in its part. So let me say again that soy is not bad character in this. It's too easy to vilify something and miss the the point. It's about preparation of soy in Asian in the west and balance which is missing from many vegetarians in their diet.

Asians fermented it because  its not very digestable in its natural form. Generally when plant food is fermented it makes it more digestable by rendering out the toxins in the substances. Cabbage into kimchi, or saurkraut is similar if anyone has ever eaten too much raw cabbage or too many beans not prepared properly knows the anti-social effects. Soy is generally the worst of the lot that people eat because the digestive problems include gas, hormonal changes which involve lower testosterone and raising estrogen, and suppress thyroid function, which is an organ that regulates thyroid function.

Asians don't eat a lot of it. There is a fallacy in American that Asians eat much of the stuff. Those in Korean know how much pork is consumed. Statistically, I don't have data on Koreans. But I know some facts.  The China Study conducted by Colin T. Campbell, found that legume consumption in China was an average of 12 grams, mean of about twelve. Japanese eat about 8 grams a day for men and 7 grams for women.

That's 2-3 teaspoons of soy. 

The reason it is fermented and not consumed in great amounts is attributed to these facts.

1. High Amounts of Phytates:

Phytates are in most plants, are a plants way to keep animals from eating them. Phytates block the absorbtion of iron, zinc, calcium, and magnesium. In a high vegetable protein diet, the absorbtion of iron can be as low as 2-3 percent.

2. Goistrogens:

They suppress your thyroid function your metabolisms and its uptake of iodine. The Japanese eat soy consumed with lots of iodine rich fish and seaweed.

3. High Amount of Estrogen:

Plants can have phytoestrogens or phytoandrogens that keep you in balance. Soy has a lot of phytoestrogen. I think it was 1 month into have soy as a staple in my diet before I realized that I wasn't thinking about sex anymore.

But that's not the whole picture.  None of this really matter if soy is not a signficant part of your diet but it really matters if you are eating a lot of it.  If your not eating it in balance with other like the Asians, you will run into problems.  That means eating a lot of unfermented soy, or even more than 3-4 tablespoons of the stuff.

3-4 tablespoons? That's not a lot.  Something that as I vegetarian, I ate a lot more of.

So with what we know about Asian cooking- that it is fermented most of the time and it's place in the cuisine is in small quantities,  people should not be consuming the massive quality of unfermented soy products that they are eating in the West today. 

The reason soy is being marketed so aggressively is for many reasons. One reason is soybeans were introduced to America to add nitrogen to soil. Corn exausts nitrogen in soil. Nitrogen makes plants big would be too simple to reduce it to that- but that's a start. So USA farmers introduced soy to add nitrogen back into the soil. We had to use all the soy grown for something.  One way to get rid of it was to introduce it into the food supply. There is so much of it that prices are low and you can sell soy milk for a premium with very low cost

However, American the American diet is really not a diet that balances out soy's less desirable effects. The Japanese eat a lot fish and meat with soy because it gives you things soy lacks as a protein which includes fats that help make testosterone and iodine. Asian herbalism has androgenic medicines in their diet that can counteract soy, such as pine pollen extract, and tiengi ginseng, and chinese dogwood.

I've read studies for soy and against soy because food science results are easily swayed by those who will get a monetary benefit by getting results that favor them. But the evidence is compelling for me to consider a balanced diet of soy for two reasons. (1) I got sick from it and my friends and (2) Asians don't eat a lot of it and they ferment it. All of this done traditionally before the publishing of research that stresses soy should be eaten in small amounts.

I still eat soy fermented. I even eat tofu sometimes.  But I eat it in harmony with other ingredients that balance out soy's less desirable effects.

Sources:

Influence of Vegetable Protein Sources on Trace Element and Mineral Bioavailability 

Campbell, Colin T. et al., The Cornell Project in China.

Nagata, C. et al., Journal of Nutrition (1998) 128:209-213.

Murphy, P.A., "Phytoestrogen Content of Processed Soybean Foods", Food Technology, January 1982, pp. 60-64.

 

 

 

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