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Newest Research On Why You Should Avoid Soy
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2, Page 3)
by Sally Fallon & Mary G. Enig,
Ph.D.
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.
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
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 diarrhea; 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.
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.
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
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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