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Collected
works on Soy Product Toxicity
contents
Newest Research On Why You Should Avoid
Soy
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.
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
Phytoestrogens: Panacea Or Poison?
The male species of tropical birds carries
the drab plumage of the female at birth and 'colors up' at maturity, somewhere
between nine and 24 months.
In 1991, Richard and Valerie James, bird
breeders in Whangerai, New Zealand, purchased a new kind of feed for their
birds - one based largely on soy protein.47 When soy-based feed was used,
their birds 'colored up' after just a few months. In fact, one bird-food
manufacturer claimed that this early development was an advantage imparted
by the feed.
A 1992 ad for Roudybush feed formula showed
a picture of the male crimson rosella, an Australian parrot that acquires
beautiful red plumage at 18 to 24 months, already brightly colored at 11
weeks old.
Unfortunately, in the ensuing years, there
was decreased fertility in the birds, with precocious maturation, deformed,
stunted and stillborn babies, and premature deaths, especially among females,
with the result that the total population in the aviaries went into steady
decline.
The birds suffered beak and bone deformities,
goiter, immune system disorders and pathological, aggressive behavior.
Autopsy revealed digestive organs in a state of disintegration. The list
of problems corresponded with many of the problems the Jameses had encountered
in their two children, who had been fed soy-based infant formula.
Startled, aghast, angry, the Jameses hired
toxicologist Mike Fitzpatrick. PhD, to investigate further. Dr Fitzpatrick's
literature review uncovered evidence that soy consumption has been linked
to numerous disorders, including infertility, increased cancer and infantile
leukemia; and, in studies dating back to the 1950s,48 that genistein in
soy causes endocrine disruption in animals.
Dr Fitzpatrick also analyzed the bird feed
and found that it contained high levels of phytoestrogens, especially genistein.
When the Jameses discontinued using soy-based feed, the flock gradually
returned to normal breeding habits and behavior.
The Jameses embarked on a private crusade
to warn the public and government officials about toxins in soy foods,
particularly the endocrine-disrupting isoflavones, genistein and diadzen.
Protein Technology International received their material in 1994.
In 1991, Japanese researchers reported
that consumption of as little as 30 grams or two tablespoons of soybeans
per day for only one month resulted in a significant increase in thyroid-stimulating
hormone.49 Diffuse goiter and hypothyroidism appeared in some of the subjects
and many complained of constipation, fatigue and lethargy, even though
their intake of iodine was adequate.
In 1997, researchers from the FDA's National
Center for Toxicological Research made the embarrassing discovery that
the goitrogenic components of soy were the very same isoflavones.50
Twenty-five grams of soy protein isolate,
the minimum amount PTI claimed to have cholesterol-lowering effects, contains
from 50 to 70 mg of isoflavones. It took only 45 mg of isoflavones in premenopausal
women to exert significant biological effects, including a reduction in
hormones needed for adequate thyroid function. These effects lingered for
three months after soy consumption was discontinued.51
One hundred grams of soy protein - the
maximum suggested cholesterol-lowering dose, and the amount recommended
by Protein Technologies International - can contain almost 600 mg of isoflavones,52
an amount that is undeniably toxic. In 1992, the Swiss health service estimated
that 100 grams of soy protein provided the estrogenic equivalent of the
Pill.53
In vitro studies suggest that isoflavones
inhibit synthesis of estradiol and other steroid hormones.54 Reproductive
problems, infertility, thyroid disease and liver disease due to dietary
intake of isoflavones have been observed for several species of animals
including mice, cheetah, quail, pigs, rats, sturgeon and sheep.55
It is the isoflavones in soy that are said
to have a favorable effect on postmenopausal symptoms, including hot flushes,
and protection from osteoporosis. Quantification of discomfort from hot
flushes is extremely subjective, and most studies show that control subjects
report reduction in discomfort in amounts equal to subjects given soy.56
The claim that soy prevents osteoporosis is extraordinary, given that soy
foods block calcium and cause vitamin D deficiencies.
If Asians indeed have lower rates of osteoporosis
than Westerners, it is because their diet provides plenty of vitamin D
from shrimp, lard and seafood, and plenty of calcium from bone broths.
The reason that Westerners have such high rates of osteoporosis is because
they have substituted soy oil for butter, which is a traditional source
of vitamin D and other fat-soluble activators needed for calcium absorption.
Birth Control Pills For Babies
But it was the isoflavones in infant formula
that gave the Jameses the most cause for concern. In 1998, investigators
reported that the daily exposure of infants to isoflavones in soy infant
formula is 6 to11 times higher on a body-weight basis than the dose that
has hormonal effects in adults consuming soy foods. Circulating concentrations
of isoflavones in infants fed soy-based formula were 13,000 to 22,000 times
higher than plasma estradiol concentrations in infants on cow's milk formula.57
Approximately 25 per cent of bottle-fed
children in the US receive soy-based formula - a much higher percentage
than in other parts of the Western world. Fitzpatrick estimated that an
infant exclusively fed soy formula receives the estrogenic equivalent (based
on body weight) of at least five birth control pills per day.58 By contrast,
almost no phytoestrogens have been detected in dairy-based infant formula
or in human milk, even when the mother consumes soy products.
Scientists have known for years that soy-based
formula can cause thyroid problems in babies. But what are the effects
of soy products on the hormonal development of the infant, both male and
female?
Male infants undergo a "testosterone surge"
during the first few months of life, when testosterone levels may be as
high as those of an adult male. During this period, the infant is programmed
to express male characteristics after puberty, not only in the development
of his sexual organs and other masculine physical traits, but also in setting
patterns in the brain characteristic of male behavior.
In monkeys, deficiency of male hormones
impairs the development of spatial perception (which, in humans, is normally
more acute in men than in women), of learning ability and of visual discrimination
tasks (such as would be required for reading).59 It goes without saying
that future patterns of sexual orientation may also be influenced by the
early hormonal environment.
Male children exposed during gestation
to diethylstilbestrol (DES), a synthetic estrogen that has effects on animals
similar to those of phytoestrogens from soy, had testes smaller than normal
on manturation.60
Learning disabilities, especially in male
children, have reached epidemic proportions. Soy infant feeding - which
began in earnest in the early 1970s - cannot be ignored as a probable cause
for these tragic developments.
As for girls, an alarming number are entering
puberty much earlier than normal, according to a recent study reported
in the journal Pediatrics.61 Investigators found that one per cent of all
girls now show signs of puberty, such as breast development or pubic hair,
before the age of three; by age eight, 14.7 per cent of white girls and
almost 50 per cent of African-American girls have one or both of these
characteristics.
New data indicate that environmental estrogens
such as PCBs and DDE (a breakdown product of DDT) may cause early sexual
development in girls.62 In the 1986 Puerto Rico Premature Thelarche study,
the most significant dietary association with premature sexual development
was not chicken - as reported in the press - but soy infant formula.63
The consequences of this truncated childhood
are tragic. Young girls with mature bodies must cope with feelings and
urges that most children are not well-equipped to handle. And early maturation
in girls is frequently a harbinger for problems with the reproductive system
later in life, including failure to menstruate, infertility and breast
cancer.
Parents who have contacted the Jameses
recount other problems associated with children of both sexes who were
fed soy-based formula, including extreme emotional behavior, asthma, immune
system problems, pituitary insufficiency, thyroid disorders and irritable
bowel syndrome - the same endocrine and digestive havoc that afflicted
the Jameses' parrots.
Dissension In The Ranks
Organizers of the Third International Soy
Symposium would be hard-pressed to call the conference an unqualified success.
On the second day of the symposium, the London-based Food Commission and
the Weston A. Price Foundation of Washington, DC, held a joint press conference,
in the same hotel as the symposium, to present concerns about soy infant
formula.
Industry representatives sat stony-faced
through the recitation of potential dangers and a plea from concerned scientists
and parents to pull soy-based infant formula from the market. Under pressure
from the Jameses, the New Zealand Government had issued a health warning
about soy infant formula in 1998; it was time for the American government
to do the same.
On the last day of the symposium, presentations
on new findings related to toxicity sent a well-oxygenated chill through
the giddy helium hype. Dr Lon White reported on a study of Japanese Americans
living in Hawaii, that showed a significant statistical relationship between
two or more servings of tofu a week and "accelerated brain aging".64
Those participants who consumed tofu in
mid-life had lower cognitive function in late life and a greater incidence
of Alzheimer's disease and dementia. "What's more," said Dr White, "those
who ate a lot of tofu, by the time they were 75 or 80 looked five years
older".65 White and his colleagues blamed the negative effects on isoflavones
- a finding that supports an earlier study in which postmenopausal women
with higher levels of circulating estrogen experienced greater cognitive
decline.66
Scientists Daniel Sheehan and Daniel Doerge,
from the National Center for Toxicological Research, ruined PTI's day by
presenting findings from rat feeding studies, indicating that genistein
in soy foods causes irreversible damage to enzymes that synthesise thyroid
hormones.67
"The association between soybean consumption
and goiter in animals and humans has a long history," wrote Dr Doerge.
"Current evidence for the beneficial effects of soy requires a full understanding
of potential adverse effects as well."
Dr Claude Hughes reported that rats born
to mothers that were fed genistein had decreased birth weights compared
to controls, and onset of puberty occurred earlier in male offspring.68
His research suggested that the effects observed in rats "...will be at
least somewhat predictive of what occurs in humans.
There is no reason to assume that there
will be gross malformations of fetuses but there may be subtle changes,
such as neurobehavioral attributes, immune function and sex hormone levels."
The results, he said, "could be nothing or could be something of great
concern...if mom is eating something that can act like sex hormones, it
is logical to wonder if that could change the baby's development".69
A study of babies born to vegetarian mothers,
published in January 2000, indicated just what those changes in baby's
development might be. Mothers who ate a vegetarian diet during pregnancy
had a fivefold greater risk of delivering a boy with hypospadias, a birth
defect of the penis.70 The authors of the study suggested that the cause
was greater exposure to phytoestrogens in soy foods popular with vegetarians.
Problems with female offspring of vegetarian
mothers are more likely to show up later in life. While soy's estrogenic
effect is less than that of diethylstilbestrol (DES), the dose is likely
to be higher because it's consumed as a food, not taken as a drug. Daughters
of women who took DES during pregnancy suffered from infertility and cancer
when they reached their twenties.
Question Marks Over GRAS Status
Lurking in the background of industry hype
for soy is the nagging question of whether it's even legal to add soy protein
isolate to food. All food additives not in common use prior to 1958, including
casein protein from milk, must have GRAS (Generally Recognized As Safe)
status. In 1972, the Nixon administration directed a re-examination of
substances believed to be GRAS, in the light of any scientific information
then available.
This re-examination included casein protein
that became codified as GRAS in 1978. In 1974, the FDA obtained a literature
review of soy protein because, as soy protein had not been used in food
until 1959 and was not even in common use in the early 1970s, it was not
eligible to have its GRAS status grandfathered under the provisions of
the Food, Drug and Cosmetic Act.71
The scientific literature up to 1974 recognized
many antinutrients in factory-made soy protein, including trypsin inhibitors,
phytic acid and genistein. But the FDA literature review dismissed discussion
of adverse impacts, with the statement that it was important for "adequate
processing" to remove them.
Genistein could be removed with an alcohol
wash, but it was an expensive procedure that processors avoided. Later
studies determined that trypsin inhibitor content could be removed only
with long periods of heat and pressure, but the FDA has imposed no requirements
for manufacturers to do so.
The FDA was more concerned with toxins
formed during processing, specifically nitrites and lysinoalanine.72 Even
at low levels of consumption - averaging one-third of a gram per day at
the time - the presence of these carcinogens was considered too great a
threat to public health to allow GRAS status.
Soy protein did have approval for use as
a binder in cardboard boxes, and this approval was allowed to continue,
as researchers considered that migration of nitrites from the box into
the food contents would be too small to constitute a cancer risk. FDA officials
called for safety specifications and monitoring procedures before granting
of GRAS status for food.
These were never performed. To this day,
use of soy protein is codified as GRAS only for this limited industrial
use as a cardboard binder. This means that soy protein must be subject
to premarket approval procedures each time manufacturers intend to use
it as a food or add it to a food.
Soy protein was introduced into infant
formula in the early 1960s. It was a new product with no history of any
use at all. As soy protein did not have GRAS status, premarket approval
was required. This was not and still has not been granted. The key ingredient
of soy infant formula is not recognized as safe.
The Next Asbestos?
"Against the backdrop of widespread praise...there
is growing suspicion that soy - despite its undisputed benefits - may pose
some health hazards," writes Marian Burros, a leading food writer for the
New York Times. More than any other writer, Ms Burros's endorsement of
a low-fat, largely vegetarian diet has herded Americans into supermarket
aisles featuring soy foods.
Yet her January 26, 2000 article, "Doubts
Cloud Rosy News on Soy", contains the following alarming statement: "Not
one of the 18 scientists interviewed for this column was willing to say
that taking isoflavones was risk free." Ms Burros did not enumerate the
risks, nor did she mention that the recommended 25 daily grams of soy protein
contain enough isoflavones to cause problems in sensitive individuals,
but it was evident that the industry had recognized the need to cover itself.
Because the industry is extremely exposed...contingency
lawyers will soon discover that the number of potential plaintiffs can
be counted in the millions and the pockets are very, very deep. Juries
will hear something like the following: "The industry has known for years
that soy contains many toxins.
At first they told the public that the
toxins were removed by processing. When it became apparent that processing
could not get rid of them, they claimed that these substances were beneficial.
Your government granted a health claim to a substance that is poisonous,
and the industry lied to the public to sell more soy."
The "industry" includes merchants, manufacturers,
scientists, publicists, bureaucrats, former bond financiers, food writers,
vitamin companies and retail stores. Farmers will probably escape because
they were duped like the rest of us. But they need to find something else
to grow before the soy bubble bursts and the market collapses: grass-fed
livestock, designer vegetables...or hemp to make paper for thousands and
thousands of legal briefs.
Extracted from Nexus Magazine, Volume 7,
Number 3 (April-May 2000)
About the Authors:
Sally Fallon is the author of Nourishing
Traditions: The Cookbook that Challenges Politically Correct Nutrition
and the Diet Dictocrats (1999, 2nd edition, New Trends Publishing, tel
+1 877 707 1776 or +1 219 268 2601) and President of the Weston A. Price
Foundation, Washington, DC (www.WestonAPrice.org)
Mary G. Enig, Ph.D., a nutritionist widely
known for her research on the nutritional aspects of fats and oils, is
a consultant, clinician, and the Director of the Nutritional Sciences Division
of Enig Associates, Inc., Silver Spring, Maryland.
She received her PhD in Nutritional Sciences
from the University of Maryland, College Park in 1984, taught a graduate
course in nutrient-drug interactions for the University's Graduate Program
in Nutritional Sciences, and held a Faculty Research Associateship from
1984 through 1991 with the Lipids Research Group in the Department of Chemistry
and Biochemistry.
Dr. Enig is a Fellow of the American College
of Nutrition, and a member of the American Institute of Nutrition. Her
many years of experience as a "bench chemist" in the analysis of food fats
and oils, provides a foundation for her active roles in food labeling and
composition issues at the federal and state levels.
Dr. Enig is a Consulting Editor to the
"Journal of the American College of Nutrition" and formerly served as a
Contributing Editor to "Clinical Nutrition." She has published 14 scientific
papers on the subject of food fats and oils, several chapters on nutrition
for books, and presented over 35 scientific papers on food and nutrition
topics.
She is the President of the Maryland Nutritionists
Association, past President of the Coalition of Nutritionists of Maryland
and was appointed by the Governor in 1986 to the Maryland State Advisory
Council on Nutrition and served as the Chairman of the Health Subcommittee
until the Council was disbanded in 1988.
COMMENT:
Sally Fallon and Dr. Enig are to be highly
commended for this much needed soy update. Together they have compiled
the most definitive document to date on why one should avoid soy. This
is a MAJOR work and I am hoping to promote it for the national media attention
that it deserves.
ENDNOTES:
1. Program for the Third International
Symposium on the Role of Soy in Preventing and Treating Chronic Disease,
Sunday, October 31, through Wednesday, November 3, 1999, Omni Shoreham
Hotel, Washington, DC.
2. Houghton, Dean, "Healthful Harvest",
The Furrow, January 2000, pp. 10-13.
3. Coleman, Richard J., "Vegetable Protein
- A Delayed Birth?" Journal of the American Oil Chemists' Society 52:238A,
April 1975.
4. See www/unitedsoybean.org.
5. These are listed in www.soyonlineservice.co.nz.
6. Wall Street Journal, October 27, 1995.
7. Smith, James F., "Healthier tortillas
could lead to healthier Mexico", Denver Post, August 22, 1999, p. 26A.
8. "Bakery says new loaf can help reduce
hot flushes", Reuters, September 15, 1997.
9. "Beefing Up Burgers with Soy Products
at School", Nutrition Week, Community Nutrition Institute, Washington,
DC, June 5, 1998, p. 2.
10. Urquhart, John, "A Health Food Hits
Big Time", Wall Street Journal, August 3, 1999, p. B1
11. "Soyabean Milk Plant in Kenya", Africa
News Service, September 1998.
12. Simoons, Frederick J., Food in China:
A Cultural and Historical Inquiry, CRC Press, Boca Raton, 1991, p. 64.
13. Katz, Solomon H., "Food and Biocultural
Evolution: A Model for the Investigation of Modern Nutritional Problems",
Nutritional Anthropology, Alan R. Liss Inc., 1987, p. 50.
14. Rackis, Joseph J. et al., "The USDA
trypsin inhibitor study. I. Background, objectives and procedural details",
Qualification of Plant Foods in Human Nutrition, vol. 35, 1985.
15. Van Rensburg et al., "Nutritional
status of African populations predisposed to esophageal cancer", Nutrition
and Cancer, vol. 4, 1983, pp. 206-216; Moser, P.B. et al., "Copper, iron,
zinc and selenium dietary intake and status of Nepalese lactating women
and their breastfed infants", American Journal of Clinical Nutrition 47:729-734,
April 1988; Harland, B.F. et al., "Nutritional status and phytate: zinc
and phytate X calcium: zinc dietary molar ratios of lacto-ovovegetarian
Trappist monks: 10 years later", Journal of the American Dietetic Association
88:1562-1566, December 1988.
16. El Tiney, A.H., "Proximate Composition
and Mineral and Phytate Contents of Legumes Grown in Sudan", Journal of
Food Composition and Analysis (1989) 2:6778.
17. Ologhobo, A.D. et al., "Distribution
of phosphorus and phytate in some Nigerian varieties of legumes and some
effects of processing", Journal of Food Science 49(1):199-201, January/February
1984.
18. Sandstrom, B. et al., "Effect of protein
level and protein source on zinc absorption in humans", Journal of Nutrition
119(1):48-53, January 1989; Tait, Susan et al., "The availability of minerals
in food, with particular reference to iron", Journal of Research in Society
and Health 103(2):74-77, April 1983.
19. Phytate reduction of zinc absorption
has been demonstrated in numerous studies. These results are summarised
in Leviton, Richard, Tofu, Tempeh, Miso and Other Soyfoods: The 'Food of
the Future' - How to Enjoy Its Spectacular Health Benefits, Keats Publishing,
Inc., New Canaan, CT, USA, 1982, p. 1415.
20. Mellanby, Edward, "Experimental rickets:
The effect of cereals and their interaction with other factors of diet
and environment in producing rickets", Journal of the Medical Research
Council 93:265, March 1925; Wills, M.R. et al., "Phytic Acid and Nutritional
Rickets in Immigrants", The Lancet, April 8,1972, pp. 771-773.
21. Rackis et al., ibid.
22. Rackis et al., ibid., p. 232.
23. Wallace, G.M., "Studies on the Processing
and Properties of Soymilk", Journal of Science and Food Agriculture 22:526-535,
October 1971.
24. Rackis, et al., ibid., p. 22; "Evaluation
of the Health Aspects of Soy Protein Isolates as Food Ingredients", prepared
for FDA by Life Sciences Research Office, Federation of American Societies
for Experimental Biology (9650 Rockville Pike, Bethesda, MD 20014), USA,
Contract No. FDA 223-75-2004, 1979.
25. See www/truthinlabeling.org.
26. Rackis, Joseph, J., "Biological and
Physiological Factors in Soybeans", Journal of the American Oil Chemists'
Society 51:161A-170A, January 1974.
27. Rackis, Joseph J. et al., "The USDA
trypsin inhibitor study", ibid.
28. Torum, Benjamin, "Nutritional Quality
of Soybean Protein Isolates: Studies in Children of Preschool Age", in
Soy Protein and Human Nutrition, Harold L Wilcke et al. (eds), Academic
Press, New York, 1979.
29. Zreik, Marwin, CCN, "The Great Soy
Protein Awakening", Total Health 32(1), February 2000.
30. IEH Assessment on Phytoestrogens in
the Human Diet, Final Report to the Ministry of Agriculture, Fisheries
and Food, UK, November 1997, p. 11.
31. Food Labeling: Health Claims: Soy
Protein and Coronary Heart Disease, Food and Drug Administration 21 CFR,
Part 101 (Docket No. 98P-0683).
32. Sheegan, Daniel M. and Daniel R Doerge,
Letter to Dockets Management Branch (HFA-305), February 18, 1999.
33. Anderson, James W. et al., "Meta-analysis
of the Effects of Soy Protein Intake on Serum Lipids", New England Journal
of Medicine (1995) 333:(5):276-282.
34. Guy, Camille, "Doctors warned against
magic, quackery", New Zealand Herald, September 9, 1995, section 8, p.
5.
35. Sander, Kate and Hilary Wilson, "FDA
approves new health claim for soy, but litte fallout expected for dairy",
Cheese Market News, October 22, 1999, p. 24.
36. Enig, Mary G. and Sally Fallon, "The
Oiling of America", NEXUS Magazine, December 1998-January 1999 and February-March
1999; also available at www.WestonAPrice.org.
37. Natural Medicine News (L & H Vitamins,
32-33 47th Avenue, Long Island City, NY 11101), USA, January/February 2000,
p. 8.
38. Harras, Angela (ed.), Cancer Rates
and Risks, National Institutes of Health, National Cancer Institute, 1996,
4th edition.
39. Searle, Charles E. (ed.), Chemical
Carcinogens, ACS Monograph 173, American Chemical Society, Washington,
DC, 1976.
40. Nagata, C. et al., Journal of Nutrition
(1998) 128:209-213.
41. Campbell, Colin T. et al., The Cornell
Project in China.
42. Chang, K.C. (ed.), Food in Chinese
Culture: Anthropological and Historical Perspectives, New Haven, 1977.
43. Messina, Mark J. et al., "Soy Intake
and Cancer Risk: A Review of the In Vitro and In Vivo Data", Nutrition
and Cancer (1994) 21(2):113-131.
44. Rackis et al, "The USDA trypsin inhibitor
study", ibid.
45. Petrakis, N.L. et al., "Stimulatory
influence of soy protein isolate on breast secretion in pre- and post-menopausal
women", Cancer Epid. Bio. Prev. (1996) 5:785-794.
46. Dees, C. et al., "Dietary estrogens
stimulate human breast cells to enter the cell cycle", Environmental Health
Perspectives (1997) 105(Suppl. 3):633-636.
47. Woodhams, D.J., "Phytoestrogens and
parrots: The anatomy of an investigation", Proceedings of the Nutrition
Society of New Zealand (1995) 20:22-30.
48. Matrone, G. et al., "Effect of Genistin
on Growth and Development of the Male Mouse", Journal of Nutrition (1956)
235-240.
49. Ishizuki, Y. et al., "The effects
on the thyroid gland of soybeans administered experimentally in healthy
subjects", Nippon Naibunpi Gakkai Zasshi (1991) 767:622-629.
50. Divi, R.L. et al., "Anti-thyroid isoflavones
from the soybean", Biochemical Pharmacology (1997) 54:1087-1096.
51. Cassidy, A. et al., "Biological Effects
of a Diet of Soy Protein Rich in Isoflavones on the Menstrual Cycle of
Premenopausal Women", American Journal of Clinical Nutrition (1994) 60:333-340.
52. Murphy, P.A., "Phytoestrogen Content
of Processed Soybean Foods", Food Technology, January 1982, pp. 60-64.
53. Bulletin de L'Office Fédéral
de la Santé Publique, no. 28, July 20, 1992.
54. Keung, W.M., "Dietary oestrogenic
isoflavones are potent inhibitors of B-hydroxysteroid dehydrogenase of
P. testosteronii", Biochemical and Biophysical Research Committee (1995)
215:1137-1144; Makela, S.I. et al., "Estrogen-specific 12 B-hydroxysteroid
oxidoreductase type 1 (E.C. 1.1.1.62) as a possible target for the action
of phytoestrogens", PSEBM (1995) 208:51-59.
55. Setchell, K.D.R. et al., "Dietary
oestrogens - a probable cause of infertility and liver disease in captive
cheetahs", Gastroenterology (1987) 93:225-233; Leopald, A.S., "Phytoestrogens:
Adverse effects on reproduction in California Quail," Science (1976) 191:98-100;
Drane, H.M. et al., "Oestrogenic activity of soya-bean products", Food,
Cosmetics and Technology (1980) 18:425-427; Kimura, S. et al., "Development
of malignant goiter by defatted soybean with iodine-free diet in rats",
Gann. (1976) 67:763-765; Pelissero, C. et al., "Oestrogenic effect of dietary
soybean meal on vitellogenesis in cultured Siberian Sturgeon Acipenser
baeri", Gen. Comp. End. (1991) 83:447-457; Braden et al., "The oestrogenic
activity and metabolism of certain isoflavones in sheep", Australian J.
Agricultural Research (1967) 18:335-348.
56. Ginsburg, Jean and Giordana M. Prelevic,
"Is there a proven place for phytoestrogens in the menopause?", Climacteric
(1999) 2:75-78.
57. Setchell, K.D. et al., "Isoflavone
content of infant formulas and the metabolic fate of these early phytoestrogens
in early life", American Journal of Clinical Nutrition, December 1998 Supplement,
1453S-1461S.
58. Irvine, C. et al., "The Potential
Adverse Effects of Soybean Phytoestrogens in Infant Feeding", New Zealand
Medical Journal May 24, 1995, p. 318.
59. Hagger, C. and J. Bachevalier, "Visual
habit formation in 3-month-old monkeys (Macaca mulatta): reversal of sex
difference following neonatal manipulations of androgen", Behavior and
Brain Research (1991) 45:57-63.
60. Ross, R.K. et al., "Effect of in-utero
exposure to diethylstilbestrol on age at onset of puberty and on post-pubertal
hormone levels in boys", Canadian Medical Association Journal 128(10):1197-8,
May 15, 1983.
61. Herman-Giddens, Marcia E. et al.,
"Secondary Sexual Characteristics and Menses in Young Girls Seen in Office
Practice: A Study from the Pediatric Research in Office Settings Network",
Pediatrics 99(4):505-512, April 1997.
62. Rachel's Environment & Health
Weekly 263, "The Wingspread Statement", Part 1, December 11, 1991; Colborn,
Theo, Dianne Dumanoski and John Peterson Myers, Our Stolen Future, Little,
Brown & Company, London, 1996.
63. Freni-Titulaer, L.W., "Premature Thelarch
in Puerto Rico: A search for environmental factors", American Journal of
Diseases of Children 140(12):1263-1267, December 1986.
64. White, Lon, "Association of High Midlife
Tofu Consumption with Accelerated Brain Aging", Plenary Session #8: Cognitive
Function, The Third International Soy Symposium, November 1999, Program,
p. 26.
65. Altonn, Helen, "Too much tofu induces
'brain aging', study shows", Honolulu Star-Bulletin, November 19, 1999.
66. Journal of the American Geriatric
Society (1998) 46:816-21.
67. Doerge, Daniel R., "Inactivation of
Thyroid Peroxidase by Genistein and Daidzein in Vitro and in Vivo; Mechanism
for Anti-Thyroid Activity of Soy", presented at the November 1999 Soy Symposium
in Washington, DC, National Center for Toxicological Research, Jefferson,
AR 72029, USA.
68. Hughes, Claude, Center for Women's
Health and Department of Obstetrics & Gynecology, Cedars-Sinai Medical
Center, Los Angeles, CA.
69. Soy Intake May Affect Fetus", Reuters
News Service, November 5, 1999.
70. "Vegetarian diet in pregnancy linked
to birth defect", BJU International 85:107-113, January 2000.
71. FDA ref 72/104, Report FDABF GRAS
- 258.
72. "Evaluation of the Health Aspects
of Soy Protein Isolates as Food Ingredients", prepared for FDA by Life
Sciences Research Office, Federation of American Societies for Experimental
Biology (FASEB) (9650 Rockville Pike, Bethesda, MD 20014, USA), Contract
No, FDA 223-75-2004, 1979.
Soy May Cause Cancer and Brain Damage
Two senior US government scientists, Drs.
Daniel Doerge and Daniel Sheehan, have revealed that chemicals in soy could
increase the risk of breast cancer in women, brain damage in both men and
women, and abnormalities in infants.
The scientists decided to break ranks
with colleagues in the FDA and oppose its decision last year to approve
a health claim that soy reduced the risk of heart disease.
They wrote an internal protest letter
warning of 28 studies revealing toxic effects of soy, mostly focusing on
chemicals in soy known as isoflavones, which have effects similar to the
female hormone estrogen.
They claim that research has shown a
clear link between soy and the potential for adverse effects in humans.
Soy may lead to health problems in animals
including altering sexual development of fetuses and causing thyroid disorders.
Some studies show that chemicals in
soy may increase the chances of estrogen-dependent breast cancer.
According to their letter:
'There is abundant evidence that some
of the isoflavones found in soy demonstrate toxicity in estrogen sensitive
tissues and in the thyroid.'
'During pregnancy in humans, isoflavones
per se could be a risk factor for abnormal brain and reproductive tract
development.'
According to one of the scientists, parents
who give their children soy milk or formulas "are exposing their children
to chemicals which we know have adverse effects in animals. It's like doing
a large uncontrolled and unmonitored experiment on infants.'
The soy industry insists that the adverse
effects seen in animals do not apply to humans.
The Guardian August 13, 2000
DR. MERCOLA'S COMMENT:
As time goes on I suspect the real truth
regarding soy will begin to emerge in even the traditional media. If my
schedule ever opens up, I plan on promoting this message more widely and
I have even reserved the domain www.nosoy.com.
If you do not yet understand the reason
why soy should not be considered a health food please review the following
links:
The ABC television news program 20/20
aired a feature story on June 8, 2000, on the dangers of soy. It was great
to see some in the mainstream media finally picking up on this story.
Besides the articles linked below, another
good resource for information on the dangers of soy is The Weston A. Price
Foundation, which has a goal to achieve a ban on the use of soy formula
for infants.
The Trouble With
Tofu: Soy and the Brain
By John D. MacArthur
"Tofu Shrinks Brain!" Not a science fiction
scenario, this sobering soybean revelation is for real. But how did the
"poster bean" of the '90s go wrong? Apparently, in many ways none of
which bode well for the brain.
In a major ongoing study involving 3,734
elderly Japanese-American men, those who ate the most tofu during midlife
had up to 2.4 times the risk of later developing Alzheimer's disease. As
part of the three-decade long Honolulu-Asia Aging Study, 27 foods and drinks
were correlated with participants' health. Men who consumed tofu at least
twice weekly had more cognitive impairment, compared with those who rarely
or never ate the soybean curd. [1,2]
"The test results were about equivalent
to what they would have been if they were five years older," said lead
researcher Dr. Lon R. White from the Hawaii Center for Health Research.
For the guys who ate no tofu, however, they tested as though they were
five years younger.
What's more, higher midlife tofu consumption
was also associated with low brain weight. Brain atrophy was assessed in
574 men using MRI results and in 290 men using autopsy information. Shrinkage
occurs naturally with age, but for the men who had consumed more tofu,
White said "their brains seemed to be showing an exaggeration of the usual
patterns we see in aging."
Phytoestrogens Soy Self Defense
Tofu and other soybean foods contain isoflavones,
three-ringed molecules bearing a structural resemblance to mammalian steroidal
hormones. White and his fellow researchers speculate that soy's estrogen-like
compounds (phytoestrogens) might compete with the body's natural estrogens
for estrogen receptors in brain cells.
Plants have evolved many different strategies
to protect themselves from predators. Some have thorns or spines, while
others smell bad, taste bad, or poison animals that eat them. Some plants
took a different route, using birth control as a way to counter the critters
who were wont to munch.
Plants such as soy are making oral contraceptives
to defend themselves, says Claude Hughes, Ph.D., a neuroendocrinologist
at Cedars-Sinai Medical Center. They evolved compounds that mimic natural
estrogen. These phytoestrogens can interfere with the mammalian hormones
involved in reproduction and growth a strategy to reduce the number and
size of predators.
Toxicologists Concerned About Soy's Health
Risks
The soy industry says that White's study
only shows an association between tofu consumption and brain aging, but
does not prove cause and effect. On the other hand, soy experts at the
National Center for Toxicological Research, Daniel Sheehan, Ph.D., and
Daniel Doerge, Ph.D., consider this tofu study very important. "It is one
of the more robust, well-designed prospective epidemiological studies generally
available. . . We rarely have such power in human studies, as well as a
potential mechanism."
In a 1999 letter to the FDA (and on the
ABC News program 20/20), the two toxicologists expressed their opposition
to the agency's health claims for soy, saying the Honolulu study "provides
evidence that soy (tofu) phytoestrogens cause vascular dementia. Given
that estrogens are important for maintenance of brain function in women;
that the male brain contains aromatase, the enzyme that converts testosterone
to estradiol; and that isoflavones inhibit this enzymatic activity, there
is a mechanistic basis for the human findings." [3]
Although estrogen's role in the central
nervous system is not well understood, White notes that "a growing body
of information suggests that estrogens may be needed for optimal repair
and replacement of neural structures eroded with aging."
One link to the puzzle may involve calcium-binding
proteins, which are associated with protection against neurodegenerative
diseases. In recent animal studies at Brigham Young University's Neuroscience
Center, researchers found that consumption of phytoestrogens via a soy
diet for a relatively short interval can significantly elevate phytoestrogens
levels in the brain and decrease brain calcium-binding proteins. [4]
Concerns About Giving Soy to Infants
The most serious problem with soy may
be its use in infant formulas. "The amount of phytoestrogens that are in
a day's worth of soy infant formula equals 5 birth control pills," says
Mary G. Enig, Ph.D., president of the Maryland Nutritionists Association.
She and other nutrition experts believe that infant exposure to high amounts
of phytoestrogens is associated with early puberty in girls and retarded
physical maturation in boys. [5]
A study reported in the British medical
journal Lancet found that the "daily exposure of infants to isoflavones
in soy infant-formulas is 6-11 fold higher on a bodyweight basis than the
dose that has hormonal effects in adults consuming soy foods." (A dose,
equivalent to two glasses of soy milk per day, that was enough to change
menstrual patterns in women. [6]) In the blood of infants tested, concentrations
of isoflavones were 13000-22000 times higher than natural estrogen concentrations
in early life. [7]
Soy Interferes with Enzymes
While soybeans are relatively high in
protein compared to other legumes, Enig says they are a poor source of
protein because other proteins found in soybeans act as potent enzyme inhibitors.
These "anti-nutrients" block the action of trypsin and other enzymes needed
for protein digestion. Trypsin inhibitors are large, tightly folded proteins
that are not completely deactivated during ordinary cooking and can reduce
protein digestion. Therefore, soy consumption may lead to chronic deficiencies
in amino acid uptake. [8]
Soy's ability to interfere with enzymes
and amino acids may have direct consequence for the brain. As White and
his colleagues suggest, "isoflavones in tofu and other soyfoods might exert
their influence through interference with tyrosine kinase-dependent mechanisms
required for optimal hippocampal function, structure and plasticity." [2]
High amounts of protein tyrosine kinases
are found in the hippocampus, a brain region involved with learning and
memory. One of soy's primary isoflavones, genistein, has been shown to
inhibit tyrosine kinase in the hippocampus, where it blocked "long-term
potentiation," a mechanism of memory formation. [9]
Tyrosine, Dopamine, and Parkinson's Disease
The brain uses the amino acids tyrosine
or phenylalanine to synthesize the key neurotransmitters dopamine and norepinephrine,
brain chemicals that promote alertness and activity. Dopamine is crucial
to fine muscle coordination. People whose hands tremble from Parkinson's
disease have a diminished ability to synthesize dopamine. An increased
incidence of depression and other mood disorders are associated with low
levels of dopamine and norepinephrine. Also, the current scientific consensus
on attention-deficit disorder points to a dopamine imbalance.
Soy has been shown to affect tyrosine
hydroxylase activity in animals, causing the utilization rate of dopamine
to be "profoundly disturbed." When soy lecithin supplements were given
throughout perinatal development, they reduced activity in the cerebral
cortex and "altered synaptic characteristics in a manner consistent with
disturbances in neural function." [10]
Researchers at Sweden's Karolinska Institute
at the National Institutes of Health and are finding a connection between
tyrosine hydroxylase activity, thyroid hormone receptors, and depleted
dopamine levels in the brain particularly in the substantia nigra, a
region associated with the movement difficulties characteristic of Parkinson's
disease. [11-13]
Soy Affects the Brain via the Thyroid Gland
Tyrosine is crucial to the brain in another
way. It's needed for the body to make active thyroid hormones, which are
a major physiological regulator of mammalian brain development. By affecting
the rate of cell differentiation and gene expression, thyroid hormones
regulate the growth and migration of neurons, including synaptic development
and myelin formation in specific brain regions. Low blood levels of tyrosine
are associated with an underactive thyroid gland.
Scientists have known for years that isoflavones
in soy products can depress thyroid function, causing goiter (enlarged
thyroid gland) and autoimmune thyroid disease. In the early 1960s, goiter
and hypothyroidism were reported in infants fed soybean diets. [14] Scientists
at the National Center for Toxicological Research showed that the soy isoflavones
genistein and daidzein "inhibit thyroid peroxidase-catalyzed reactions
essential to thyroid hormone synthesis." [15]
Japanese researchers studied effects on
the thyroid from soybeans administered to healthy subjects. They reported
that consumption of as little as 30 grams (two tablespoons) of soybeans
per day for only one month resulted in a significant increase in thyroid
stimulating hormone (TSH), which is produced by the brain's pituitary gland
when thyroid hormones are too low. Their findings suggested that "excessive
soybean ingestion for a certain duration might suppress thyroid function
and cause goiters in healthy people, especially elderly subjects." [16]
Thyroid Hormones and Fetal Brain Development
Thyroid alterations are among the most
frequently encountered autoimmune conditions in children. Researchers at
Cornell University Medical College showed that the "frequency of feedings
with soy-based milk formulas in early life was significantly higher in
children with autoimmune thyroid disease." [17] In a previous study, they
found that twice as many diabetic children had received soy formula in
infancy as compared to non-diabetic children. [18]
Recognizing the risk, Swiss health authorities
recommend "very restrictive use" of soy for babies. In England and Australia,
public health agencies tell parents to first seek advice from a doctor
before giving their infants soy formula. The New Zealand Ministry of Health
recommends that "Soy formula should only be used under the direction of
a health professional for specific medical indications. . . Clinicians
who are treating children with a soy-based infant formula for medical conditions
should be aware of the potential interaction between soy infant formula
and thyroid function." [19]
Thyroid hormones exert their influence
during discrete windows of time. Inappropriate hormone levels can have
a devastating effect on the developing human brain, especially during the
first 12 weeks of pregnancy when the fetus depends on the mother's thyroid
hormones for brain development. After that, both maternal and fetal thyroid
hormone levels affect the central nervous system.
A 1999 study published in the New England
Journal of Medicine showed that pregnant women with underactive thyroids
were four times more likely to have children with low IQs if the disorder
is left untreated. The study found that 19% of the children born to mothers
with thyroid deficiency had IQ scores of 85 or lower, compared with only
5% of those born to mothers without such problems. [20]
Thyroid, Brain, and Environmental Toxins
Children exposed prenatally and during
infancy to common environmental toxins like dioxin and polychlorinated
biphenyls (PCBs) can suffer behavioral, learning, and memory problems because
these chemicals may be disrupting the normal action of thyroid hormone.
[21]
Soybeans grown in the United States contain
residues of the pesticide dieldrin, an organochlorine similar to DDT. Although
both chemicals were banned in the 1970s, dieldrin still persists in soils
and is absorbed through the roots. Today it is the most toxic residue found
on domestic soybeans. [22] In Silent Spring, Rachel Carson warned that
dieldrin is nearly 50 times as poisonous as DDT. In addition to disrupting
hormones, it can have long delayed neurological effects, ranging from loss
of memory to mania. [23]
Combinations of insecticides, weed killers,
and artificial fertilizers even at low levels have measurable detrimental
effects on thyroid and other hormones as well as on the brain. [24] EPA
scientists now want to upgrade the commonly used herbicide, atrazine, to
a "likely carcinogen." In animal tests, atrazine attaches to sites on the
hypothalamus, a crucial brain region involved with regulating levels of
stress and sex hormones. [25]
Individuals newly diagnosed with Parkinson's
disease were more than twice as likely to have been exposed to insecticides
in their home, compared to those without the disease. [26]
Soy formulas for infants can contain other
neurotoxins: aluminum, cadmium, and fluoride. Studies found that aluminum
concentrations in soy-based formulas were a 100-fold greater compared to
human breast milk, while cadmium content was 8-15 times higher than in
milk-based formulas. In an Australian study, the fluoride content of soy-based
formulas ranged from 1.08 to 2.86 parts per million. The authors concluded
that "prolonged consumption (beyond 12 months of age) of infant formula
reconstituted with optimally-fluoridated water could result in excessive
amounts of fluoride being ingested." A study of Connecticut children revealed
that mild-to-moderate fluorosis was strongly associated with soy-based
infant formula use. [27-30]
In May 2000, Boston Physicians for Social
Responsibility released their report, "The Toxic Threats to Child Development."
In the section on neurotoxins, they concluded: "Studies in animals and
human populations suggest that fluoride exposure, at levels that are experienced
by a significant proportion of the population whose drinking water is fluoridated,
may have adverse impacts on the developing brain." [31]
Iodine vs. Fluorine
The thyroid gland uses tyrosine and the
natural element iodine to make thyroxine (T4), a thyroid hormone containing
four iodine atoms. The other, much more biologically active thyroid hormone
is tri-iodothyronine (T3), which has three iodine atoms. Lack of dietary
iodine has long been identified as the problem in diminished thyroid hormone
synthesis.
According to the International Council
for the Control of Iodine Deficiency Disorders: "Iodine deficiency has
been called the world's major cause of preventable mental retardation.
Its severity can vary from mild intellectual blunting to frank cretinism,
a condition that includes gross mental retardation, deaf mutism, short
stature, and various other defects. . . The damage to the developing brain
results in individuals poorly equipped to fight disease, learn, work effectively,
or reproduce satisfactorily."
This crucial role of iodine is another
reason why the thyroid gland is especially vulnerable today. Canadian researcher
Andreas Schuld has documented more than 100 studies during the last 70
years that demonstrate adverse effects of fluoride on the thyroid gland.
[32] Schuld says, "Fluorine, being the strongest in the group of halogens,
will seriously interfere with iodine and iodine synthesis, forcing more
urinary elimination of ingested iodine as fluoride ingestion or absorption
increases."
Fluorides were actually used in the past,
specifically to reduce thyroid function. In the 1930s through to the 1960s
fluorides at 0.9mg to 4.5mg/day were given as effective anti-thyroid medication
to hyperthyroid patients." [33] Russian researchers in the 1980s concluded
that prolonged consumption of drinking water with a raised fluorine content
was a risk factor of more rapid development of thyroid pathology. [34]
A major source of fluoride exposure in
the United States is fluoridated drinking water including foods and drinks
manufactured and processed with this treated water. (Only about 5% of the
world's population is fluoridated, and more than half live in North America.
99% of western continental Europe has rejected, banned, or stopped the
addition of fluoride compounds to their drinking water. [35]) Also, approximately
45 million pounds of hydrogen fluoride are released from U.S. coal-fired
plants every year into the environment.
Soy Phytates Inhibit Zinc Absorption
Another way that soybeans may affect brain
function is because of their phytic acid content. Phytic acid is an organic
acid present in the outer portion of all seeds. Also known as phytates,
they block the uptake of essential minerals in the intestinal tract: calcium,
magnesium, iron, and especially zinc. According to research cited by the
Weston A. Price Foundation, soybeans have very high levels of a form of
phytic acid that is particularly difficult to neutralize and which interferes
with zinc absorption more completely than with other minerals.
The soy industry acknowledges the problem,
noting that "one-half cup of cooked soybeans contains one mg of zinc. However,
zinc is poorly absorbed from soyfoods." As for iron, "both phytate and
soy protein reduce iron absorption so that the iron in soyfoods is generally
poorly absorbed." [36]
Nutritionist Sally Fallon, author of Nourishing
Traditions: The Cookbook that Challenges Politically Correct Nutrition
and the Diet Dictocrats, says that as early as 1967, researchers testing
soy formula found that it caused negative zinc balance in every infant
to whom it was given. Even when the diets were additionally supplemented
with zinc, there was a strong correlation between phytate content in formula
and poor growth. She warns that "a reduced rate of growth is especially
serious in the infant as it causes a delay in the accumulation of lipids
in the myelin, and hence jeopardizes the development of the brain and nervous
system."
Zinc and the Brain
Relatively high levels of zinc are found
in the brain, especially the hippocampus. Zinc plays an important role
in the transmission of the nerve impulse between brain cells. Deficiency
of zinc during pregnancy and lactation has been shown to be related to
many congenital abnormalities of the nervous system in offspring. In children,
"insufficient levels of zinc have been associated with lowered learning
ability, apathy, lethargy, and mental retardation." [37]
The USDA references a study of 372 Chinese
school children with very low levels of zinc in their bodies. The children
who received zinc supplements had the most improved performance especially
in perception, memory, reasoning, and psychomotor skills such as eye-hand
coordination. Three earlier studies with adults also showed that changes
in zinc intake affected cognitive function. [38]
New research has identified a specific
contingent of neurons, called "zinc-containing" neurons, which are found
almost exclusively in the forebrain, where in mammals they have evolved
into a "complex and elaborate associational network that interconnects
most of the cerebral cortices and limbic structures." This suggests the
importance of zinc in the normal and pathological processes of the cerebral
cortex. [39] Furthermore, age-related tissue zinc deficiency may contribute
to brain cell death in Alzheimer's dementia. [40]
Safe Soy
To produce soy milk, the beans are first
soaked in an alkaline solution, then heated to about 115 degrees C in order
to remove as much of the trypsin inhibitors as possible. Fallon says this
method destroys most, but not all of the anti-nutrients, however it has
the "unhappy side effect of so denaturing the proteins that they become
very difficult to digest and much reduced in effectiveness." Furthermore,
phytates remain in soy milk to block the uptake of essential minerals.
Only a long period of fermentation will
significantly reduce the phytate content of soybeans, as well as the trypsin
inhibitors that interfere with enzymes and amino acids. Therefore, fermented
soy products such as tempeh and miso (not tofu) provide nourishment that
is easily assimilated.
Links to Further Information:
Soy Online Service (http://www.soyonlineservice.co.nz/)
Weston A. Price Foundation (http://www.westonaprice.org/)
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Originally Appearing on Brain.com
DR. MERCOLA'S COMMENTS: Further information
documenting the unwise choice many people are making by consuming such
large amounts of soy. They are being deceived by the effective marketing
efforts of the multi-billion dollar edible oil industry which, in many
ways, is not to dissimilar to what we see with the drug industry's influence
in the traditional medical paradigm.
Soy: Too Good
to be True
by Brandon Finucan & Charlotte Gerson
While even in 1966 there was considerable
research on the harmful substances within soybeans, you'll be hard pressed
to find articles today that claim soy is anything short of a miracle-food.
As soy gains more and more popularity through industry advertising, we
are moved once again to raise our voice of concern.
The Soybean Industry in America
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 byproducts. At your local supermarket, soy can now be found disguised
as everything from soy cheese, milk, burgers and hot dogs, to ice cream,
yogurt, 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 isnít always mentioned on the box cover.
Today, an alarming 60% of the food on America's supermarket shelves contain
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 prepackaged frozen meals, soy plays a major
role.
Where the soybean goes wrong?
Here at the Gerson Institute, we feel the
positive aspects of the soybean are overshadowed by their potential for
harm. Soybeans in fact contain a large number of dangerous substances.
One among them is phytic acid, also called phytates. This organic acid
is present in the bran or hulls of all seeds and legumes, but none have
the high level of phytates that soybeans do. These acids block the bodyís
uptake of essential minerals like calcium, magnesium, iron and especially
zinc. Adding to the high-phytate problem, soybeans are very resistant to
phytate reducing techniques, such as long, slow cooking.
Soybeans also contain potent enzyme inhibitors.
These inhibitors block uptake of trypsin and other enzymes that the body
needs for protein digestion. Normal cooking does not deactivate these harmful
"antinutrients," that can cause serious gastric distress, reduced protein
digestion and can lead to chronic deficiencies in amino acid uptake.
Beyond these, soybeans also contain hemagglutinin,
a clot promoting substance that causes red blood cells to clump together.
These clustered blood cells are unable to properly absorb oxygen for distribution
to the body's tissues, and cannot help in maintaining good cardiac health.
Hemagglutinin and trypsin inhibitors are both "growth depressant" substances.
Although the act of fermenting soybeans does deactivate both trypsin inhibitors
and hemagglutinin, precipitation and cooking do not. Even though these
enzyme inhibitors are reduced in levels within precipitated soy products
like tofu, they are not altogether eliminated.
Only after a long period of fermentation
(as in the creation of miso or tempeh) are the phytate and "antinutrient"
levels of soybeans reduced, making their nourishment available to the human
digestive system. The high levels of harmful substances remaining in precipitated
soy products leave their nutritional value questionable at best, and in
the least, potentially harmful.
What About the Studies?
In recent years, several studies have been
made regarding the soybeanís effect on human health. The results
of those studies, largely underwritten by various factions of the soy industry,
were of course overwhelmingly in favor of soy. The primary claims about
soy's health benefits are based purely on bad science. Although primary
arguments for cancer patients to use soy focus on statistics showing low
rates of breast, colon and prostate cancer among Asian people, there are
obvious facts being utterly ignored. While the studies boast that Asian
women suffer far fewer cases of breast cancer than American women do, the
hype neglects to point out that these Asian women eat a diet that is dramatically
different than their American counterparts.
The standard Asian diet consists of more
natural products, far less fatty meat, greater amounts of vegetables and
more fish. Their diets are also lower in chemicals and toxins, as they
eat far fewer processed (canned, jarred, pickled, frozen) foods. It is
likely these studies are influenced by the fact that cancer rates rise
among Asian people who move to the U.S. and adopt American-ized diets.
Of course, this change of diet goes hand-in-hand with a dramatic shift
in lifestyle. Ignoring the remarkable diet and lifestyle changes, to assume
only that reduced levels of soy in these Americanized Asian diets is a
primary factor in greater cancer rates is poor judgment, and as stated
above, bad science. The changes of diet and lifestyle must be considered
to reach the correct conclusion.
A widely circulated article, written by
Jane E. Allen, AP Science Writer, titled, "Scientists Suggest More Soy
in Diet", cites in the course of a symposium, numerous speakers discussing
the probable advantages of soy under the title, "Health Impact of Soy Protein."
However, the article states that the $50,000 symposium "was underwritten
by Protein Technologies International of St. Louis, a DuPont subsidiary
that makes soy protein!" In the course of the same symposium, Thomas Clarkson,
professor of comparative medicine at Wake Forest University, states "Current
hormone replacement therapy has been a dismal failure from a public health
point of view," not because PremarinÆ is known to cause uterine or
other female organ cancers, but "because only 20 percent of the women who
could benefit from it are taking it."
Other popular arguments in support of soy
state that fermented products, like tempeh or natto, contain high levels
of vitamin B-12. However, these supportive arguments fail to mention that
soy's B-12 is an inactive B-12 analog, not utilized as a vitamin in the
human body. Some researchers speculate this analog may actually serve to
block the body's B-12 absorption. It has also been found that allergic
reactions to soybeans are far more common than to all other legumes. Even
the American Academy of Pediatrics admits that early exposure to soy through
commercial infant formulas, may be a leading cause of soy allergies among
older children and adults.
In his classic book, A Cancer Therapy
- Results of 50 Cases (p. 237), Dr. Gerson put "Soy and Soy Products" on
the "FORBIDDEN" list of foods for Gerson Therapy patients. At the time,
his greatest concerns were two items: the high oil content of soy and soy
products, and the rather high rate of allergic reactions to soy. Soybeans
can add as much as 9 grams of fat per serving, typically adding an average
of 5 grams of fat per serving when part of an average American diet.
The Extraction Process
The processes which render the soybean
"edible" are also the processes which render it "inedible." In fermenting
soybeans, the process entails that the beans be purÈed and soaked
in an alkaline solution. The purÈed mixture is then heated to about
115C (239F) inside a pressure cooker. This heating and soaking process
destroys most, but not all, of the anti-nutrients. At the same time, it
has the unwelcome effect of denaturing the proteins of the beans so they
become very difficult to digest and greatly reduced in effectiveness. Unfortunately,
the alkaline solution also produces a carcinogen, lysinealine, while it
reduces the already low cystine content within the soybean. Cystine plays
an essential role in liver detoxification, allowing our bodies to filter
and eliminate toxins. Without proper amounts of cystine, the protein complex
of the soybean becomes useless, unless the diet is fortified with cystine-rich
meat, egg, or dairy products - not an option for Gerson patients.
To the soybean's credit, they do contain
large amounts of beneficial omega-3 fatty acids, but these are particularly
susceptible to rancidity when subjected to high pressures and temperatures.
Unfortunately, high pressure and temperature are required to remove soybean
oil from the soybean.
Before soybeans are sent to your table,
they undergo a rigorous process to strip them of their oil. Hexane or other
solvents are first applied to help separate the oil from the beans, leaving
trace amounts of these toxins in the commercial product. Hexane by definition
is; "any of five colorless, volatile, liquid hydrocarbons C6H14 of the
paraffin series," and cannot be the least bit beneficial in anyoneís
diet. After the oil is extracted, the defatted flakes are used to form
the three basic soy protein products. With the exception of full-fat soy
flour, all soybean products contain trace amounts of carcinogenic solvents.
Personal Experiences
The following letter was received in November
1998: "I have used soy milk for 12 years with no problems. About 9 months
ago, I started to have heart palpitations. I thought maybe that I was in
menopause, but I wasnít. I added more potassium to my diet and magnesium
and vitamin E. No change. I am already decaffeinated but I also took all
sugar out of my diet. I lost 25 pounds and felt great except for the palpitations.
I tried hawthorn and garlic but nothing was helping. Recently I came down
with acute bronchitis and could only drink water because even the soy milk
made me have horrendous bouts of coughing. I realized that after a few
days my heart palpitations had stopped. I didn't think anything of it because
it never occurred to me that soy was the culprit. As soon as I started
drinking it again, my heart went crazy. I went off it for a week and then
changed brands. Within 30 minutes of drinking only 4 ounces [of soy milk],
my heart was all over the place. I've noticed that it takes about 24 to
36 hours for my heart to settle down. I wondered if your research turned
up anything like this in regard to soy. I know it is not within the definition
of an allergy, but something is definitely going on. I called the manufacturer
of the soy milk, but they were of no help. I am very upset because I only
drink soy milk and water. I also use the soy milk to make protein shakes
(with what elseÖbut soy protein)."
In our November/December 1996 issue of
the Gerson Healing Newsletter we described another case: a pregnant lady
who looked very ill and was terribly deficient! She also described her
son, age five, who had many allergies and infections - both were using
a good deal of soy in their diet. I recommended that they discontinue the
use of all soy products. At the time, I had only just run across this situation.
However, a year later, I was in the same area for a lecture, and the lady
invited me to dinner. She had cut out all soy products: her skin was now
rosy, her face filled out, her sunken eyes normal, her black circles gone
and her little boy, now six, was in greatly improved health.
Just last week, another interesting story
came to our attention. A patient at the Gerson Certified Hospital in Mexico
told us of her son, now 25, who has total lack of hair (Alopecia) with
the exception of eyebrows and eyelashes. She added that this started when
he was just three years old. Since the mother asked me about this situation,
I considered the problem for a moment. Then, looking at the parents who
both have normal hair, I figured that the boy's problem was most probably
not genetic. So, I asked the mother if he used a lot of soy. She said,
no. But then, after thinking about the question for a moment, she said
that at about one year of age, the boy had many allergies, so she regularly
fed him soy milk! I explained to her that the enzyme and nutrient blocking
ability of soy and the likelihood of the soy milk being the cause of his
condition starting at age three. Since we had just witnessed the case of
a patient whose hair grew back on his bald pate, (See "Practitioner Training"
article in this issue) after being bald for some 20 years, I cautiously
suggested that a complete change of diet accompanied by intensive detoxification,
may be able to overcome the problem.
Gerson Institute Newsletter Volume 14 #3
This article is the first of two parts.
Part Two will be next week
http://www.soyonlineservice.co.nz/
ìSoybean Products: A Recipe for
Disaster?î Extracted from Nexus Magazine, Vol. 4, No. 3 (Apr-May
1997), http://www.icom.net/ ~nexus/soya.html
Soy Protein Council, http://www.spcouncil.org
ìJeopardizing the Future? Genetic
Engineering, Food and the Environmentî, by Dr. Michael Hanson and
Jean Halloran (Consumer Policy Institute /Consumers Union), http://www.pmac.net/
ìMonsanto Genetically Engineered
Soya has Elevated Hormone Levels: Public Health Threatî (Oct. 1997),
http://www.holisticmed.com/
ìMonsantoís Toxic Roundupî
(Nov. 1996),http://www.holisticmed.com/
ìToxicity from Genetically-Engineered
Foodsî, http://www.holisticmed.com/
Eat the State!, ìNature & Politicsî
by Jeffrey St. Clair and Alexander Cockburn (Feb. 1999),
'Concerns Regarding Soybeansî, http://www.rheumatic.org/soy.htm
COMMENT: This is an excellent summary of
some of the major reasons why soy is not the health food that you think
it is. There are literally billions of dollars of influence in the edible
oil industry that is promoting soy's use in natural medical circles so
it's use can be then promoted in the general medical public. They are even
able to fool otherwise knowledgeable natural medical physicians. I am a
monthly columnist in the Townsend Letters and another columnist, Dr. Hudson,
who was voted Naturopathic doctor of the year, has an article this month
extolling soy's values. Needless to say I quickly wrote a letter to Townsend
asking them to print the other side of the soy story. In the meantime,
you can save you and your family some potential problems by limiting any
soy use to fermented products only, like tempeh or miso.
Link Between
High Soy Diet During Pregnancy and
Nursing and Eventual Developmental Changes in Children
Two separate studies one in animals and
the other in humans that considered together suggest that a diet high
in soybeans and other legumes during pregnancy and breastfeeding may have
a subtle but long-term impact on the development of children.
Soybeans and other food-source plants
contain compounds, called phytoestrogens or isoflavones, which have been
found to produce a variety of mild hormonal actions within the human body.
Studies in recent years are confirming
that the estrogenic effects of these compounds may be beneficial in preventing
or treating a variety of conditions such as the unpleasant symptoms of
menopause.
We are a very different creature when
we are an embryo or a fetus or a child or a teenager. Were very different
when we are a reproductive-age adult or an aging adult.
At each stage, we have a different profile
of risk or benefit. At the beginning of the life span, when tissues in
our bodies are being organized in utero and in the first months of life,
there is good reason to believe -- based on animal studies and in some
human observations -- that sex hormones are very important in getting things
organized properly.
These hormones influence the way the brain
is organized, the way the reproductive organs and cells develop, even the
way immune function develops. Therefore, if mom is eating something or
has in her body fat something that can act like sex hormones, it is logical
to wonder if that could change the babys development. If there is an impact,
is it positive, negative or irrelevant?
To determine if unborn babies are indeed
exposed to phytoestrogens, the researchers analyzed amniotic fluid samples
of 54 pregnant women from the Los Angeles area. No phytoestrogens were
detected in 11 samples, extremely high levels were found in seven samples,
and the remaining 36 contained modest levels.
The study concluded that about 80 percent
of the fetuses were exposed to estrogenic isoflavones at concentrations
ranging from 20 to 180 times the levels of naturally occurring female sex
hormones in the amniotic fluid of female fetuses.
The amniotic fluid samples were taken
during routine amniocentesis between 16 and 20 weeks of gestation after
a babys organs have formed but during a critical stage of development.
The researchers used an animal model to
begin to determine whether this in utero phytoestrogen exposure might affect
the organizational stage of the fetus and the future development of the
child. In a controlled study, they fed pregnant female rats genistein,
an isoflavone that is known to have significant estrogenic properties.
The rat study was carefully designed to
take into account the obvious differences that exist in the developmental
and life cycles of rats and humans, and to correlate as closely as possible
to the timing of the amniotic fluid sampling. The mother rats were given
genistein from day 14 of gestation through post-natal day 21 when the rat
pups were weaned.
Developmentally, this time period is almost
exactly the same time that the human amniotic fluid samples were obtained.
The major steps of formation of organs in the body occur early on, in both
rats and humans. Therefore, the treatment of the rats was intentionally
delayed until major organ formation had occurred.
The goal was to assess the effects of
exposure on the developing organism, and this is about as close as one
can get to being able to take measurable samples from humans and match
them up with meaningful findings in an animal model.
According to the results, the genist |