Newest Research On Why You Should Avoid Soy
by Sally Fallon
email: SAFallon@aol.com & Mary G. Enig, PhD email: MGEnig@aol.com
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).
Each year,
research on the health effects of soy and soybean components seems to
increase exponentially. Furthermore, research is not just expanding in
the primary areas under investigation, such as cancer, heart disease and
osteoporosis; new findings suggest that soy has potential benefits that
may be more extensive than previously thought.
So writes Mark Messina, PhD, General Chairperson of the Third
International Soy Symposium, held in Washington, DC, in November 1999.1
For four days, well-funded scientists gathered in Washington made
presentations to an admiring press and to their sponsors - United
Soybean Board, American Soybean Association, Monsanto, Protein
Technologies International, Central Soya, Cargill Foods, Personal
Products Company, SoyLife, Whitehall-Robins Healthcare and the soybean
councils of Illinois, Indiana, Kentucky, Michigan, Minnesota, Nebraska,
Ohio and South Dakota.
The symposium marked the apogee of a decade-long marketing campaign to
gain consumer acceptance of tofu, soy milk, soy ice cream, soy cheese,
soy sausage and soy derivatives, particularly soy isoflavones like
genistein and diadzen, the oestrogen-like compounds found in soybeans.
It coincided with a US Food and Drug Administration (FDA) decision,
announced on October 25, 1999, 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.
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, 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
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.
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
diarrhoea; that some had upper respiratory infections; and that others
suffered from rash and fever.
It should be noted that the researchers did not dare to use soy products
to help the children recover from malnutrition, and were obliged to
supplement the soy-sugar mixture with nutrients largely absent in soy
products - notably, vitamins A, D and B12, iron, iodine and zinc.
FDA Health Claim Challenged
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 veggieburgers
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)
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.
See also http://www.mercola.com/article/soy/index.htm
Soy: Is it Healthy or is it Harmful?
By Dr. Joseph Mercola
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