Hazzards of Unfermented Soy foods Part 1

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Research On Why You Should Avoid Soy

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1-3 of 3 by Sally Fallon & Mary G. Enig, Ph.D.Cinderella's Dark

Side

The

propaganda that has created the soy sales miracle is all the more

remarkable because, only a few decades ago, the soybean was considered

unfit to eat - even in Asia. During the Chou Dynasty (1134-246 BC) the

soybean was designated one of the five sacred grains, along with

barley, wheat, millet and rice.However, the pictograph for the soybean,

which dates from earlier times, indicates that it was not first used as

a food; for whereas the pictographs for the other four grains show the

seed and stem structure of the plant, the pictograph for the soybean

emphasizes the root structure. Agricultural literature of the period

speaks frequently of the soybean and its use in crop rotation.

Apparently the soy plant was initially used as a method of fixing

nitrogen.13 The soybean did not serve as a food until the discovery of

fermentation techniques, some time during the Chou Dynasty. The first

soy foods were fermented products like tempeh, natto, miso and soy

sauce.At a later date, possibly in the 2nd century BC, Chinese

scientists discovered that a purée of cooked soybeans could be

precipitated with calcium sulfate or magnesium sulfate (plaster of

Paris or Epsom salts) to make a smooth, pale curd - tofu or bean curd.

The use of fermented and precipitated soy products soon spread to other

parts of the Orient, notably Japan and Indonesia.The Chinese did not

eat unfermented soybeans as they did other legumes such as lentils

because the soybean contains large quantities of natural toxins or

"antinutrients". First among them are potent enzyme inhibitors that

block the action of trypsin and other enzymes needed for protein

digestion.These inhibitors are large, tightly folded proteins that are

not completely deactivated during ordinary cooking. They can produce

serious gastric distress, reduced protein digestion and chronic

deficiencies in amino acid uptake. In test animals, diets high in

trypsin inhibitors cause enlargement and pathological conditions of the

pancreas, including cancer.14Soybeans 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.15Analysis 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.25In 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.27Yet 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.6Public

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.8The 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."29The "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.31One 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.33A

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."34There 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.41Assuming 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.46Phytoestrogens:

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.50Twenty-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.53In 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.57Approximately 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