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Is soy the modern wonder food its proponents claim or is there something they forgot to tell us?

Our supermarket shelves are filled with products containing some form of soy, yet many of these products do not advertise this fact. This revelation is generally not very alarming however, because when we do hear about soy, it is usually in praise of all its benefits but perhaps we should look a little deeper before becoming too comfortable with this new 'wonder food'.

In 1924 soybean production in the U.S. was only at 1.8 million acres harvested, but by 1954, the harvested acres grew to 18.9 million. Today, the soybean is America's third largest crop (harvesting 72 million acres in 1998), supplying more than 50 percent of the world's soybean demand.

Most of these beans are made into animal feed and are manufactured into soy oil for use as vegetable oil, margarine and shortening. Of the traditional uses for soy as a food, only soy sauce enjoys widespread consumption in the American diet. Tofu, measuring 90 percent of Asia's use of the soybean, has gained more popularity in the U.S., but soy is still nowhere near a measurable component of the average American diet - or is it?

For more than 20 years now, the soy industry has concentrated on finding alternative uses and new markets for soybeans and soy by-products. At your local supermarket, soy can now be found disguised as everything from soy cheese, milk, burgers and hot dogs, to ice cream, yoghurt, vegetable oil, baby formula and flour (to name just a few). These are often marketed as low fat, dairy-free, or as a high-protein, meat substitute for vegetarians. But soy isn't always mentioned on the box cover.

Today, an alarming 60% of the food on America's supermarket shelves contains soy derivatives (i.e. soy flour, textured vegetable protein, partially hydrogenated soy bean oil, soy protein isolate). When you look at the ingredients list, and really look at the contents of the "Average American Diet," from snack foods and fast foods to pre-packaged frozen meals, soy plays a major role.

The chief concern about the consumption of large amounts of soy is that there is a risk of mega-dosing on isoflavones. If soy consumers follow the advice of Protein Technologies International (manufacturers of isolated soy protein) and consume 100 grams of soy protein per day, their daily genistein intake could easily exceed 200 milligrams per day. This level of genistein intake should definitely be avoided. For comparison, it should be noted that Japanese males consume, on average, less than 10 milligrams of genistein per day (Fukutake M, Takahashi M, Ishida K, Kawamura H, Sugimura T, Wakabayashi K; Food Chem Toxicol 1996, 34:457-61).

In short, not that much, and contrary to what the industry may claim, soy has never been a staple in Asia. A study of the history of soy use in Asia shows that it was used by the poor during times of extreme food shortage, and only then the soybeans were carefully prepared (e.g. by lengthy fermentation) to destroy the soy toxins. Yes, the Asians understood soy alright! Many vegetarians in the USA, and Europe and Australasia would think nothing of consuming 8 ounces (about 220 grams) of tofu and a couple of glasses of soy milk per day, two or three times a week. But this is well in excess of what Asians typically consume; they generally use small portions of soy to complement their meal. It should also be noted that soy is not the main source of dietary protein and that a regime of calcium-set tofu and soy milk bears little resemblance to the soy consumed traditionally in Asia.

Perhaps the best survey of what types/quantities of soy are eaten in Asia comes from data from a validated, semi quantitative food frequency questionnaire that surveyed 1,242 men and 3,596 women who participated in an annual health check-up program in Takayama City, Japan. This survey identified that the soy products consumed were tofu (plain, fried, deep-fried, or dried), miso, fermented soybeans, soymilk, and boiled soybeans. The estimated amount of soy protein consumed from these sources was 8.00 ± 4.95 g/day for men and 6.88 ± 4.06 g/day for women (Nagata C, Takatsuka N, Kurisu Y, Shimizu H; J Nutr 1998, 128:209-13).

According to KC Chang, editor of Food in Chinese Culture, the total caloric intake due to soy in the Chinese diet in the 1930's was only 1.5%, compared with 65% for pork. For more information on the traditional use of soy products contact the Weston A Price Foundation.

Ever heard the industry line that 'soy formulas must be safe because Asian infants have been eating soy for centuries'. Just another piece of false advertising, a little like the claims that 'soy formulas are better than breast milk' that many parents that have fed soy formulas testify to. And to set the record straight, soy was seldom used in infant feeding in Asia.

It seems those same Western notions that made Asians out to be greater soy consumers than they were are still prevalent. Why is that? Asia is a huge market for the soy industry and the soy industry efforts to convince Asians that their ancestors ate much more soy than they actually did are purely profit driven.

Multiple millions of dollars are spent on soy research each year. Most State Soybean Boards fund their own research programmes (e.g., Arkansas Soybean Board which spent US$1.1 Million in research in 1998-1999) but the grants offered are insignificant when compared with that of the United States Department of Agriculture (USDA).

The USDA Soybean Promotion and Research Program was established by the Soybean Promotion and Research Order and is authorised by the Soybean Promotion, Research, and Consumer Information Act [7 U.S.C. 6301-6311]. The Act was passed as part of the 1990 Farm Bill. It authorized the establishment of a national soybean promotion, research, and consumer information program. The program became effective on July 9, 1991, when the Order was published. Assessments began September 1, 1991

The program's goal is to strengthen the position of soybeans in the marketplace and to maintain and expand domestic and foreign markets and uses for soybeans and soybean products. It is funded by a mandatory assessment of 0.5 of 1 percent of the net market price of soybeans. All producers marketing soybeans must pay the assessment. Assessments under this program total approximately $80 million annually and are used to fund promotional and informational campaigns and to conduct research with the objective of expanding and improving the use of soybeans and soybean products.

You can read more about the USDA Soybean Promotion and Research Program at the United Soybean Board Site or read the American Soybean Association (ASA) policy on research, education and natural resources, which also clearly spells out the ASA's motivation for research; to make more money.

For Adults
A glass a day melts the thyroid away. From USA Woman's World, Mar 16 2001. AVOIDING SOY .... As little as 30mg of soy isoflavones--the amount in 5-8 ounces of soymilk - have been proven to suppress thyroid function. "The isoflavones in soy act like a hormone in the body. And in many women, especially those who eat large amounts of concentrated soy powder or take isoflavone supplements, this disturbs the body's hormonal balance, triggering or worsening thyroid problems," explains Dr. Larian Gillespie, author of "The Goddess Diet". Some experts are even calling for the makers of soy products to remove these antithyroid isoflavones from their products.

Soy protein has been assessed by the Australia/New Zealand Food Authority as posing potential hazards to consumers as to sexual maturation, sexual differences, foetal and neonatal brain development, and to thyroid function of children and adults (ANZFA)

It failed its evaluation by the US FDA as a human food because carcinogens were thought to pose a health hazard (GRAS STATUS) it does not comply with FAO/Codex guidelines for safe vegetable protein as it is reproductively, chronically, mutagenically and teratagenically toxic. (GUIDELINE GL/89)

Apart from the US Department of Agriculture's approvals as a meat substitute, as far as Soy Information Service has been able to find out, soy protein is not a legally approved food anywhere in the world

For Infants
In simple terms. The dose in soy baby formulas means an infant gets the dose-equivalent of an adult woman taking up to ten pills a day. Or, a baby in its first year gets a total antifertility dose of 100 Pill-equivalents.

How much soy is safe to eat?

For infants, we believe any soy is too much soy. Adults consuming soy should also exercise caution and only use in small amounts, if at all. Recipes containing soy or soy products may always be changed to include other foods.

The observations from the Ishizuki Thyroid Clinic study indicate significant, goitrogenic effects in subjects fed 30 g soybeans per day. Based on the concentrations of isoflavones found in Japanese soybeans, 30 g of soybeans could contribute up to 23 mg total genistein and 10 mg of total daidzein. For a 70 kg adult this would equate to an intake of 0.33 mg/kg-body weight of genistein and 0.14 mg/kg-body weight of daidzein per day.

This amount of isoflavone consumption is approximately three times higher than the amount typically consumed in Japan, which is 0.08 to 0.13 mg/kg-body weight of total genistein per day for a 70 kg adult.

As an approximate guide 30 mg of soy isoflavones can be found in:
Soybeans and soy flours: 9 - 20g (0.3 - 0.7oz).
Soy mince: 12g (0.4oz).
Tofu: 50 - 110g (1.8 - 3.9oz).
Soymilks: 150 - 240g (5.3 - 8.5oz).
Miso: 35 - 45g (1.2 - 1.6oz).
Soybean sprouts: 80g (2.8oz).

In summary, Read those labels and avoid consuming too much soy protein or other soy by-products. Note; fermented soy products such as soy sauce and Tempeh are rendered relatively safe by the fermentation process and these are usually only consumed in very small quantities anyway. Regarding soy sauce, there have been cases of toxins found in certain soy sauces, which are completely unrelated to the problems with soy protein. These were isolated cases and were limited to certain obscure brands usually only found in specialty shops. To be on the safe side, stay with recognised major Japanese brands such as Kikkoman.
Soy Online Service
The Weston A. Price Foundation