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by Sally Fallon & Mary G. Enig, Ph.D.
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Cinderella's Dark Side |
The propaganda that has created the soy sales
miracle is all the more remarkable because, only a few decades ago, the
soybean was considered unfit to eat - even in Asia. During the Chou
Dynasty (1134-246 BC) the soybean was designated one of the five sacred
grains, along with barley, wheat, millet and rice. However, the pictograph
for the soybean, which dates from earlier times, indicates that it was not
first used as a food; for whereas the pictographs for the other four
grains show the seed and stem structure of the plant, the pictograph for
the soybean emphasizes the root structure. Agricultural literature of the
period speaks frequently of the soybean and its use in crop rotation.
Apparently the soy plant was initially used as a method of fixing
nitrogen.13
The soybean did not serve as a food until the discovery of fermentation
techniques, some time during the Chou Dynasty. The first soy foods were
fermented products like tempeh, natto, miso and soy sauce. At a later
date, possibly in the 2nd century BC, Chinese scientists discovered that a
purée of cooked soybeans could be precipitated with calcium sulfate or
magnesium sulfate (plaster of Paris or Epsom salts) to make a smooth, pale
curd - tofu or bean curd. The use of fermented and precipitated soy
products soon spread to other parts of the Orient, notably Japan and
Indonesia.
The Chinese did not eat unfermented soybeans as they did other legumes
such as lentils because the soybean contains large quantities of natural
toxins or "antinutrients". First among them are potent enzyme inhibitors
that block the action of trypsin and other enzymes needed for protein
digestion. These inhibitors are large, tightly folded proteins that are
not completely deactivated during ordinary cooking. They can produce
serious gastric distress, reduced protein digestion and chronic
deficiencies in amino acid uptake. In test animals, diets high in trypsin
inhibitors cause enlargement and pathological conditions of the pancreas,
including cancer.14
Soybeans also contain haemagglutinin, a clot-promoting substance that
causes red blood cells to clump together.
Trypsin inhibitors and haemagglutinin are growth inhibitors. Weanling rats
fed soy containing these antinutrients fail to grow normally.
Growth-depressant compounds are deactivated during the process of
fermentation, so once the Chinese discovered how to ferment the soybean,
they began to incorporate soy foods into their diets. In precipitated
products, enzyme inhibitors concentrate in the soaking liquid rather than
in the curd. Thus, in tofu and bean curd, growth depressants are reduced
in quantity but not completely eliminated.
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Soy
also contains goitrogens - substances that depress thyroid function |
Additionally 99% a very large percentage of soy is
genetically modified and it also has one of the highest percentages
contamination by pesticides of any of our foods.
Soybeans are high in phytic acid, present in the bran or hulls of all
seeds. It's a substance that can block the uptake of essential minerals -
calcium, magnesium, copper, iron and especially zinc - in the intestinal
tract. Although not a household word, phytic acid has been extensively
studied; there are literally hundreds of articles on the effects of phytic
acid in the current scientific literature. Scientists are in general
agreement that grain- and legume-based diets high in phytates contribute
to widespread mineral deficiencies in third world countries.15 Analysis
shows that calcium, magnesium, iron and zinc are present in the plant
foods eaten in these areas, but the high phytate content of soy- and
grain-based diets prevents their absorption.
The soybean has one of the highest phytate levels of any grain or legume
that has been studied,16 and the phytates in soy are highly resistant to
normal phytate-reducing techniques such as long, slow cooking.17 Only a
long period of fermentation will significantly reduce the phytate content
of soybeans. When precipitated soy products like tofu are consumed with
meat, the mineral-blocking effects of the phytates are reduced.18 The
Japanese traditionally eat a small amount of tofu or miso as part of a
mineral-rich fish broth, followed by a serving of meat or fish.
Vegetarians who consume tofu and bean curd as a substitute for meat and
dairy products risk severe mineral deficiencies. The results of calcium,
magnesium and iron deficiency are well known; those of zinc are less so.
Zinc is called the intelligence mineral because it is needed for optimal
development and functioning of the brain and nervous system. It plays a
role in protein synthesis and collagen formation; it is involved in the
blood-sugar control mechanism and thus protects against diabetes; it is
needed for a healthy reproductive system. Zinc is a key component in
numerous vital enzymes and plays a role in the immune system. Phytates
found in soy products interfere with zinc absorption more completely than
with other minerals.19 Zinc deficiency can cause a "spacey" feeling that
some vegetarians may mistake for the "high" of spiritual enlightenment.
Milk drinking is given as the reason why second-generation Japanese in
America grow taller than their native ancestors. Some investigators
postulate that the reduced phytate content of the American diet - whatever
may be its other deficiencies - is the true explanation, pointing out that
both Asian and Western children who do not get enough meat and fish
products to counteract the effects of a high phytate diet, frequently
suffer rickets, stunting and other growth problems.20
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Soy Protein Isolate: Not So Friendly |
Soy processors have worked hard to get these
antinutrients out of the finished product, particularly soy protein
isolate (SPI) which is the key ingredient in most soy foods that imitate
meat and dairy products, including baby formulas and some brands of soy
milk.
SPI is not something you can make in your own kitchen. Production takes
place in industrial factories where a slurry of soy beans is first mixed
with an alkaline solution to remove fiber, then precipitated and separated
using an acid wash and, finally, neutralized in an alkaline solution. Acid
washing in aluminum tanks leaches high levels of aluminum into the final
product. The resultant curds are spray- dried at high temperatures to
produce a high-protein powder. A final indignity to the original soybean
is high-temperature, high-pressure extrusion processing of soy protein
isolate to produce textured vegetable protein (TVP).
Much of the trypsin inhibitor content can be removed through
high-temperature processing, but not all. Trypsin inhibitor content of soy
protein isolate can vary as much as fivefold.21 (In rats, even low-level
trypsin inhibitor SPI feeding results in reduced weight gain compared to
controls.22) But high-temperature processing has the unfortunate
side-effect of so denaturing the other proteins in soy that they are
rendered largely ineffective.23 That's why animals on soy feed need lysine
supplements for normal growth.
Nitrites, which are potent carcinogens, are formed during spray-drying,
and a toxin called lysinoalanine is formed during alkaline processing.24
Numerous artificial flavorings, particularly MSG, are added to soy protein
isolate and textured vegetable protein products to mask their strong "beany"
taste and to impart the flavor of meat.25
In feeding experiments, the use of SPI increased requirements for vitamins
E, K, D and B12 and created deficiency symptoms of calcium, magnesium,
manganese, molybdenum, copper, iron and zinc.26 Phytic acid remaining in
these soy products greatly inhibits zinc and iron absorption; test animals
fed SPI develop enlarged organs, particularly the pancreas and thyroid
gland, and increased deposition of fatty acids in the liver.27
Yet soy protein isolate and textured vegetable protein are used
extensively in school lunch programs, commercial baked goods, diet
beverages and fast food products. They are heavily promoted in third world
countries and form the basis of many food giveaway programs.
In spite of poor results in animal feeding trials, the soy industry has
sponsored a number of studies designed to show that soy protein products
can be used in human diets as a replacement for traditional foods. An
example is "Nutritional Quality of Soy Bean Protein Isolates: Studies in
Children of Preschool Age", sponsored by the Ralston Purina Company.28 A
group of Central American children suffering from malnutrition was first
stabilized and brought into better health by feeding them native foods,
including meat and dairy products. Then, for a two-week period, these
traditional foods were replaced by a drink made of soy protein isolate and
sugar. All nitrogen taken in and all nitrogen excreted was measured in
truly Orwellian fashion: the children were weighed naked every morning,
and all excrement and vomit gathered up for analysis. The researchers
found that the children retained nitrogen and that their growth was
"adequate", so the experiment was declared a success.
Whether the children were actually healthy on such a diet, or could remain
so over a long period, is another matter. The researchers noted that the
children vomited "occasionally", usually after finishing a meal; that over
half suffered from periods of moderate diarrhoea; that some had upper
respiratory infections; and that others suffered from rash and fever.
It should be noted that the researchers did not dare to use soy products
to help the children recover from malnutrition, and were obliged to
supplement the soy-sugar mixture with nutrients largely absent in soy
products - notably, vitamins A, D and B12, iron, iodine and zinc.
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Marketing the Perfect Food |
"Just imagine you could grow the perfect food.
This food not only would provide affordable nutrition, but also would be
delicious and easy to prepare in a variety of ways. It would be a
healthful food, with no saturated fat. In fact, you would be growing a
virtual fountain of youth on your back forty." The author is Dean
Houghton, writing for The Furrow,2 a magazine published in 12 languages by
John Deere. "This ideal food would help prevent, and perhaps reverse, some
of the world's most dreaded diseases. You could grow this miracle crop in
a variety of soils and climates. Its cultivation would build up, not
deplete, the land...this miracle food already exists... It's called soy."
Just imagine. Farmers have been imagining - and planting more soy. What
was once a minor crop, listed in the 1913 US Department of Agriculture
(USDA) handbook not as a food but as an industrial product, now covers 72
million acres of American farmland. Much of this harvest will be used to
feed chickens, turkeys, pigs, cows and salmon. Another large fraction will
be squeezed to produce oil for margarine, shortenings and salad dressings.
Advances in technology make it possible to produce isolated soy protein
from what was once considered a waste product - the defatted, high-protein
soy chips - and then transform something that looks and smells terrible
into products that can be consumed by human beings. Flavorings,
preservatives, sweeteners, emulsifiers and synthetic nutrients have turned
soy protein isolate, the food processors' ugly duckling, into a New Age
Cinderella.
The new fairy-tale food has been marketed not so much for her beauty but
for her virtues. Early on, products based on soy protein isolate were sold
as extenders and meat substitutes - a strategy that failed to produce the
requisite consumer demand. The industry changed its approach. "The
quickest way to gain product acceptability in the less affluent society,"
said an industry spokesman, "is to have the product consumed on its own
merit in a more affluent society."3 So soy is now sold to the upscale
consumer, not as a cheap, poverty food but as a miracle substance that
will prevent heart disease and cancer, whisk away hot flushes, build
strong bones and keep us forever young. The competition - meat, milk,
cheese, butter and eggs - has been duly demonised by the appropriate
government bodies. Soy serves as meat and milk for a new generation of
virtuous vegetarians.
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Marketing
Costs Money |
This is
especially when it
needs to be bolstered with "research", but there's plenty of funds
available. All soybean producers pay a mandatory assessment of one-half to
one per cent of the net market price of soybeans. The total - something
like US$80 million annually4 - supports United Soybean's program to
"strengthen the position of soybeans in the marketplace and maintain and
expand domestic and foreign markets for uses for soybeans and soybean
products". State soybean councils from Maryland, Nebraska, Delaware,
Arkansas, Virginia, North Dakota and Michigan provide another $2.5 million
for "research".5 Private companies like Archer Daniels Midland also
contribute their share. ADM spent $4.7 million for advertising on Meet the
Press and $4.3 million on Face the Nation during the course of a year.6
Public relations firms help convert research projects into newspaper
articles and advertising copy, and law firms lobby for favorable
government regulations. IMF money funds soy processing plants in foreign
countries, and free trade policies keep soybean abundance flowing to
overseas destinations.
The push for more soy has been relentless and global in its reach. Soy
protein is now found in most supermarket breads. It is being used to
transform "the humble tortilla, Mexico's corn-based staple food, into a
protein-fortified 'super-tortilla' that would give a nutritional boost to
the nearly 20 million Mexicans who live in extreme poverty".7 Advertising
for a new soy-enriched loaf from Allied Bakeries in Britain targets
menopausal women seeking relief from hot flushes. Sales are running at a
quarter of a million loaves per week.8
The soy industry hired Norman Robert Associates, a public relations firm,
to "get more soy products onto school menus".9 The USDA responded with a
proposal to scrap the 30 per cent limit for soy in school lunches. The
NuMenu program would allow unlimited use of soy in student meals. With soy
added to hamburgers, tacos and lasagna, dieticians can get the total fat
content below 30 per cent of calories, thereby conforming to government
dictates. "With the soy-enhanced food items, students are receiving better
servings of nutrients and less cholesterol and fat."
Soy milk has posted the biggest gains, soaring from $2 million in 1980 to
$300 million in the US last year.10 Recent advances in processing have
transformed the gray, thin, bitter, beany-tasting Asian beverage into a
product that Western consumers will accept - one that tastes like a
milkshake, but without the guilt.
Processing miracles, good packaging, massive advertising and a marketing
strategy that stresses the products' possible health benefits account for
increasing sales to all age groups. For example, reports that soy helps
prevent prostate cancer have made soy milk acceptable to middle-aged men.
"You don't have to twist the arm of a 55- to 60-year-old guy to get him to
try soy milk," says Mark Messina. Michael Milken, former junk bond
financier, has helped the industry shed its hippie image with
well-publicized efforts to consume 40 grams of soy protein daily.
America today, tomorrow the world. Soy milk sales are rising in Canada,
even though soy milk there costs twice as much as cow's milk. Soybean milk
processing plants are sprouting up in places like Kenya.11 Even China,
where soy really is a poverty food and whose people want more meat, not
tofu, has opted to build Western-style soy factories rather than develop
western grasslands for grazing animals.12
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FDA Health Claim Challenged |
On October 25, 1999 the
US Food and Drug Administration (FDA) decided to allow a health claim for
products "low in saturated fat and cholesterol" that contain 6.25 grams of
soy protein per serving. Breakfast cereals, baked goods, convenience food,
smoothie mixes and meat substitutes could now be sold with labels touting
benefits to cardiovascular health, as long as these products contained one
heaping teaspoon of soy protein per 100-gram serving.
The best marketing strategy for a product that is inherently unhealthy is,
of course, a health claim.
"The road to FDA approval," writes a soy apologist, "was long and
demanding, consisting of a detailed review of human clinical data
collected from more than 40 scientific studies conducted over the last 20
years. Soy protein was found to be one of the rare foods that had
sufficient scientific evidence not only to qualify for an FDA health claim
proposal but to ultimately pass the rigorous approval process."29
The "long and demanding" road to FDA approval actually took a few
unexpected turns. The original petition, submitted by Protein Technology
International, requested a health claim for isoflavones, the estrogen-like
compounds found plentifully in soybeans, based on assertions that "only
soy protein that has been processed in a manner in which isoflavones are
retained will result in cholesterol lowering". In 1998, the FDA made the
unprecedented move of rewriting PTI's petition, removing any reference to
the phyto-estrogens and substituting a claim for soy protein - a move that
was in direct contradiction to the agency's regulations. The FDA is
authorized to make rulings only on substances presented by petition.
The abrupt change in direction was no doubt due to the fact that a number
of researchers, including
scientists employed by
the US Government, submitted documents indicating that isoflavones are
toxic.
The FDA had also received, early in 1998, the final British Government
report on phytoestrogens, which failed to find much evidence of benefit
and warned against potential adverse effects.30
Even with the change to soy protein isolate, FDA bureaucrats engaged in
the "rigorous approval process" were forced to deal nimbly with concerns
about mineral blocking effects, enzyme inhibitors, goitrogenicity,
endocrine disruption, reproductive problems and increased allergic
reactions from consumption of soy products.31
One of the strongest letters of protest came from Dr Dan Sheehan and Dr
Daniel Doerge, government researchers at the National Center for
Toxicological Research.32 Their pleas for warning labels were dismissed as
unwarranted.
"Sufficient scientific evidence" of soy's cholesterol-lowering properties
is drawn largely from a 1995 meta-analysis by Dr James Anderson, sponsored
by Protein Technologies International and published in the New England
Journal of Medicine.33
A meta-analysis is a review and summary of the results of many clinical
studies on the same subject. Use of meta-analyses to draw general
conclusions has come under sharp criticism by members of the scientific
community. "Researchers substituting meta-analysis for more rigorous
trials risk making faulty assumptions and indulging in creative
accounting," says Sir John Scott, President of the Royal Society of New
Zealand. "Like is not being lumped with like. Little lumps and big lumps
of data are being gathered together by various groups."34
There is the added temptation for researchers, particularly researchers
funded by a company like Protein Technologies International, to leave out
studies that would prevent the desired conclusions. Dr Anderson discarded
eight studies for various reasons, leaving a remainder of twenty-nine. The
published report suggested that individuals with cholesterol levels over
250 mg/dl would experience a "significant" reduction of 7 to 20 per cent
in levels of serum cholesterol if they substituted soy protein for animal
protein. Cholesterol reduction was insignificant for individuals whose
cholesterol was lower than 250 mg/dl.
In other words, for most of us, giving up steak and eating vegieburgers
instead will not bring down blood cholesterol levels. The health claim
that the FDA approved "after detailed review of human clinical data" fails
to inform the consumer about these important details.
Research that ties soy to positive effects on cholesterol levels is
"incredibly immature", said Ronald M. Krauss, MD, head of the Molecular
Medical Research Program and Lawrence Berkeley National Laboratory.35 He
might have added that studies in which cholesterol levels were lowered
through either diet or drugs have consistently resulted in a greater
number of deaths in the treatment groups than in controls - deaths from
stroke, cancer, intestinal disorders, accident and suicide.36
Cholesterol-lowering measures in the US have fuelled a $60 billion per
year cholesterol-lowering industry, but have not saved us from the ravages
of heart disease.
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Soy and Cancer |
The new FDA ruling does not allow any claims about
cancer prevention on food packages, but that has not restrained the
industry and its marketers from making them in their promotional
literature.
"In addition to protecting the heart," says a vitamin company brochure,
"soy has demonstrated powerful anticancer benefits...the Japanese, who eat
30 times as much soy as North Americans, have a lower incidence of cancers
of the breast, uterus and prostate."37
Indeed they do. But the Japanese, and Asians in general, have much higher
rates of other types of cancer, particularly cancer of the esophagus,
stomach, pancreas and liver.38 Asians throughout the world also have high
rates of thyroid cancer.39 The logic that links low rates of reproductive
cancers to soy consumption requires attribution of high rates of thyroid
and digestive cancers to the same foods, particularly as soy causes these
types of cancers in laboratory rats.
Just how much soy do Asians eat? A 1998 survey found that the average
daily amount of soy protein consumed in Japan was about eight grams for
men and seven for women - less than two teaspoons.40 The famous Cornell
China Study, conducted by Colin T. Campbell, found that legume consumption
in China varied from 0 to 58 grams per day, with a mean of about twelve.41
Assuming that two-thirds of legume consumption is soy, then the maximum
consumption is about 40 grams, or less than three tablespoons per day,
with an average consumption of about nine grams, or less than two
teaspoons. A survey conducted in the 1930s found that soy foods accounted
for only 1.5 per cent of calories in the Chinese diet, compared with 65
per cent of calories from pork.42 (Asians traditionally cooked with lard,
not vegetable oil!)
Traditionally fermented soy products make a delicious, natural seasoning
that may supply important nutritional factors in the Asian diet. But
except in times of famine, Asians consume soy products only in small
amounts, as condiments, and not as a replacement for animal foods - with
one exception. Celibate monks living in monasteries and leading a
vegetarian lifestyle find soy foods quite helpful because they dampen
libido.
It was a 1994 meta-analysis by Mark Messina, published in Nutrition and
Cancer, that fuelled speculation on soy's anticarcinogenic properties.43
Messina noted that in 26 animal studies, 65 per cent reported protective
effects from soy. He conveniently neglected to include at least one study
in which soy feeding caused pancreatic cancer - the 1985 study by
Rackis.44 In the human studies he listed, the results were mixed. A few
showed some protective effect, but most showed no correlation at all
between soy consumption and cancer rates. He concluded that "the data in
this review cannot be used as a basis for claiming that soy intake
decreases cancer risk". Yet in his subsequent book, The Simple Soybean and
Your Health, Messina makes just such a claim, recommending one cup or 230
grams of soy products per day in his "optimal" diet as a way to prevent
cancer.
Thousands of women are now consuming soy in the belief that it protects
them against breast cancer. Yet, in 1996, researchers found that women
consuming soy protein isolate had an increased incidence of epithelial
hyperplasia, a condition that presages malignancies.45 A year later,
dietary genistein was found to stimulate breast cells to enter the cell
cycle - a discovery that led the study authors to conclude that women
should not consume soy products to prevent breast cancer.46
Take
this preliminary
to see if your condition could respond to treatment.
 Part
2
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