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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)
This article is reproduced with the kind permission of
Mercola.com, one of the top two
most visited health websites in the world where you can sign up for Dr.
Mercola's free health email newsletter.
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.
Another article on How Much Soy Asians Actually Eat
ENDNOTES:
1. Program for the
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Soy During Pregnancy
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