Some people have publicly said that soy is a beneficial food
and we should eat more of it, especially as a replacement for red
meat. Many vegetarians rely heavily on it for their protein. It has been claimed to be good for women who are menopausal or peri-menopausal.
But how true is this? Let's take a look at some of the myths
about soy, and the real truth. Thanks to the Weston
A Price Foundation for the following information:
Myth: Use of soy
as a food dates back many thousands of years.
Truth: Soy was first used as a food during the
late Chou dynasty (1134-246 BC), only after the Chinese learned
to ferment soy beans to make foods like tempeh, natto and tamari.
Myth: Asians consume
large amounts of soy foods.
Truth: Average consumption of soy foods in Japan
and China is 10 grams (about 2 teaspoons) per day. Asians consume
soy foods in small amounts as a condiment, and not as a replacement
for animal foods.
Myth: Modern soy
foods confer the same health benefits as traditionally fermented
Truth: Most modern soy foods are not fermented
to neutralize toxins in soybeans, and are processed in a way that
denatures proteins and increases levels of carcinogens.
Myth: Soy foods
provide complete protein.
Truth: Like all legumes, soy beans are deficient
in sulfur-containing amino acids methionine and cystine. In addition,
modern processing denatures fragile lysine.
soy foods can provide vitamin B12 in vegetarian diets.
Truth: The compound that resembles vitamin B12
in soy cannot be used by the human body; in fact, soy foods cause
the body to require more B12
Myth: Soy formula
is safe for infants.
Truth: Soy foods contain trypsin inhibitors that
inhibit protein digestion and affect pancreatic function. In test
animals, diets high in trypsin inhibitors led to stunted growth
and pancreatic disorders. Soy foods increase the body’s requirement
for vitamin D, needed for strong bones and normal growth. Phytic
acid in soy foods results in reduced bioavailabilty of iron and
zinc which are required for the health and development of the brain
and nervous system. Soy also lacks cholesterol, likewise essential
for the development of the brain and nervous system. Megadoses of
phytoestrogens in soy formula have been implicated in the current
trend toward increasingly premature sexual development in girls
and delayed or retarded sexual development in boys.
Myth: Soy foods
can prevent osteoporosis.
Truth: Soy foods can cause deficiencies in calcium
and vitamin D, both needed for healthy bones. Calcium from bone
broths and vitamin D from seafood, lard and organ meats prevent
osteoporosis in Asian countries—not soy foods.
Myth: Modern soy
foods protect against many types of cancer.
Truth: A British government report concluded that
there is little evidence that soy foods protect against breast cancer
or any other forms of cancer. In fact, soy foods may result in an
increased risk of cancer.
Myth: Soy foods
protect against heart disease.
Truth: In some people, consumption of soy foods
will lower cholesterol, but there is no evidence that lowering cholesterol
improves one’s risk of having heart disease.
Myth: Soy estrogens
(isoflavones) are good for you.
Truth: Soy isoflavones are phyto-endocrine disrupters.
At dietary levels, they can prevent ovulation and stimulate the
growth of cancer cells. Eating as little as 30 grams (about 4 tablespoons)
of soy per day can result in hypothyroidism with symptoms of lethargy,
constipation, weight gain and fatigue.
Myth: Soy foods
are safe and beneficial for women to use in their postmenopausal
Truth: Soy foods can stimulate the growth of estrogen-dependent
tumors and cause thyroid problems. Low thyroid function is associated
with difficulties in menopause.
in soy foods can enhance mental ability.
Truth: A recent study found that women with the
highest levels of estrogen in their blood had the lowest levels
of cognitive function; In Japanese Americans tofu consumption in
mid-life is associated with the occurrence of Alzheimer’s
disease in later life.
Myth: Soy isoflavones
and soy protein isolate have GRAS (Generally Recognized as Safe)
Truth: Archer Daniels Midland (ADM) recently withdrew
its application to the FDA for GRAS status for soy isoflavones following
an outpouring of protest from the scientific community. The FDA
never approved GRAS status for soy protein isolate because of concern
regarding the presence of toxins and carcinogens in processed soy.
Myth: Soy foods
are good for your sex life.
Truth: Numerous animal studies show that soy foods
cause infertility in animals. Soy consumption enhances hair growth
in middle-aged men, indicating lowered testosterone levels. Japanese
housewives feed tofu to their husbands frequently when they want
to reduce his virility.
Myth: Soy beans
are good for the environment.
Truth: Most soy beans grown in the US are genetically
engineered to allow farmers to use large amounts of herbicides.
Myth: Soy beans
are good for developing nations.
Truth: In third world countries, soybeans replace
traditional crops and transfer the value-added of processing from
the local population to multinational corporations.
does this mean we shouldn't eat soy?
Yes. Unfermented soy products should be avoided. Soy that has been fermented has much of the
anti-nutrients neutralised, and can be safely eaten in small amounts.
This includes tempeh, miso and tamari.
But like the Asians, think of soy as a condiment - a small part
of a balanced diet. Don't rely on it for your protein.
summarise the dangers of soy:
- High levels of phytic acid in soy reduce assimilation
of calcium, magnesium, copper, iron and zinc. Phytic acid in soy
is not neutralized by ordinary preparation methods such as soaking,
sprouting and long, slow cooking. High phytate diets have caused
growth problems in children.
- Trypsin inhibitors in soy interfere with protein
digestion and may cause pancreatic disorders. In test animals
soy containing trypsin inhibitors caused stunted growth.
- Soy phytoestrogens disrupt endocrine function
and have the potential to cause infertility and to promote breast
cancer in adult women.
- Soy phytoestrogens are potent antithyroid agents
that cause hypothyroidism and may cause thyroid cancer. In infants,
consumption of soy formula has been linked to autoimmune thyroid
disease. They also block thyroid medication, so people on those
meds shouldn't have soy at all.
- Vitamin B12 analogs in soy are not absorbed and
actually increase the body’s requirement for B12.
- Soy foods increase the body’s requirement
for vitamin D.
- Fragile proteins are denatured during high temperature
processing to make soy protein isolate and textured vegetable
- Processing of soy protein results in the formation
of toxic lysinoalanine and highly carcinogenic nitrosamines.
- Free glutamic acid or MSG, a potent neurotoxin,
is formed during soy food processing and additional amounts are
added to many soy foods.
- Soy foods contain high levels of aluminum which
is toxic to the nervous system and the kidneys.
For more information check out the Soy
Alert section of the Weston A Price Foundation, and soyonlineservice.co.nz
For a personal persepctive on the effects
of soy, here is a letter that was printed in the Winter, 2002
edition of Wise Traditions, the quarterly
magazine of the Weston A Price Foundation.
To this I can add that I know of more than one man who has
had a major reduction in sex drive after eating soy regularly.
fter stopping eating soy, things went back to normal.
AND THE BRAIN
Thanks for your website! I found it by doing a Netscape search
on isoflavones which took me to soyonlineservice.co.nz
which took me to you.
Until 2 years ago I was a regular consumer of homemade soymilk.
I have a PhD in plant physiology and over the years I systematically
worked to optimize the process I used at home so that I could
make a soymilk much more palatable than any on the market.
I had an interest in eventually starting a business to make
it. But then I learned that I probably had an adverse reaction
to isoflavones in the soymilk and 1 stopped consuming soyfoods.
I tried taking isolated soy isoflavones. basically just
to see what effect they had and also because they were reported
to be good for prostate health (I am 57). (I am aware that
there are studies pro and con benefit to prostate.) I took
2 SoyCare tablets (a total of 50 mg Novasoy isoflavones)-
A few hours later I found that it was difficult to speak and
I nearly got into a serious accident due to impairment in
judging the speed of a car. I definitely had serious mental
impairment which I attributed to the isoflavone supplement.
(This was gone by the next day.) I don't think it was due
to an allergic reaction or mini-stroke.
Once before I had similar difficulty in speech when a doctor
gave me an atropine-like medicine, Atropine antagonizes acetylcholine
action, which triggers some of the nerves involved in memory.
Memory is an essential component of speech!
Previously I had thought (based on ignorance) that isoflavones
in soy probably had insignificant health effects. After the
reaction to the isoflavones, I starting searching Bioabstracts
for studies on soy isoflavones. I quickly learned that genistein
is a potent inhibitor of tyrosine kinase, a key enzyme in
mediating cell responses to our natural cell growth factors.
(It had been used for this purpose in over 1000 research studies!)
That did not sound like something I wanted in my food! Furthermore,
I found several studies that showed that tyrosine kinase is
also involved in triggering of nerves involved in memory,
and this is blocked by genistein! My memory was flaky enough
already and I quit eating soy products, except for a few subsequent
trials of soy milk.
Besides inhibition of lyrosine kinase, adverse cognitive
effects of soymilk could also be due to anti-estrogenic actions
(estrogens are important for speech and memory in both males
and females) or to anti-thyroid action. Or maybe to all three!
All my adult life I have been bothered by rather severe
seasonal affective disorder (SAD, winter mental sluggishness)
when I lived at northern latitudes. In the last two years
I have rarely drunk soymilk, but when I did, it seemed to
worsen the SAD and each time I felt an undesirable aggressiveness.
(A recent study showed soy isoflavones increased the potent
androgen dihydrotestosterone in men.) I think my particular
physiology made me more susceptible to soy's adverse effects.
Subsequently I learned of the Hawaiian study on elderly Japanese.
It was the first time I heard that soy may cause cognitive
Gene Samuels Reston, VA
Another soy testamonial that has been doing the
rounds by email lately. As there is no name on it, it can't be verified.
But it's a sobering story, very detailed and with a ring of truth.
Read it and decide for yourself whether there could be any truth
This is my true story, nothing altered.
These are facts, as they relate to my experience, my opinions
based on what I have read and felt am relating them to warn
other young health-conscious women who are unwittingly harming
In 1989, I graduated from high school in Texas and couldn't
wait to hit the big college city. One of the changes I wanted
to make was to eat healthier.
Once I moved to health-conscious Austin, Texas, I began to
fortify my body with the best and healthiest foods I could
find. Tofu was the main ingredient in every healthy dish and
I bought soya milk almost every day. I used it for everything
from cereal to smoothies or just to drink for a quick snack.
I bought soya muffins, miso soup with tofu, soyabeans, soyabean
All the literature in all the health and fitness magazines
said that soya protected you against everything from heart
disease to breast cancer. It was the magical isoflavones,
the estrogen-like hormones that all worked to help you stay
young and healthy . I looked great, I was working out all
the time, but my menstrual cycle was off.
At 20, I started taking birth control pills to regulate my
menstrual cycle. In addition to this I began to suffer from
painful periods, began to get puffy, it was as though I was
losing my muscle tone, began to suffer from depression and
getting hot flashes. I mistook all this for PMS since my periods
were irregular. By the time I was 25, my periods were so bad
I couldn't walk. The birth control pills never made them regular
or less painful so I decided to stop taking them. I went on
like this for another two years until I realized my pain wasn't
At 27, my gynecologist found two cysts in my uterus. Both
were the size of tennis balls. I went through surgery to have
them removed and thank God they were benign. The gynecologist
told me to go back on birth control pills. I didn't.
In 1998, he discovered a lump in my breast. Again, I went
through surgery and again it was benign.
In November 2000 my glands swelled up and my gums became
inflamed. Thinking I had a tooth infection I went to the dentist
who told me that teeth were not the problem. After a dose
of antibiotics the swelling still did not go down.
At this point I could feel a tiny nodule on the right side
of my neck. I told my mother I had thyroid trouble. She thought
I was being silly. No one in the family suffered from thyroid
trouble. Going on a hunch I saw a specialist who diagnosed
me with Papillary Thyroid Carcinoma. After a series of tests
he told me it was cancer. My fiancé and I sat stunned.
We were not prepared and I was so scared. We scheduled surgery
The specialist told us that it would only be after the operation
that a pathologist would be able to tell us for sure if it
was cancer. They found a tumor at my right lobe composed of
irregular cells and another smaller tumor growing on the left,
so the entire thyroid was removed.
They told me that after undergoing radioactive iodine I would
be safe and assured me that I could live a long life.
After treatment I began to search for the cause of all these
problems. I never once thought it could be all the soya I
had consumed for nearly ten years. After all, soya is healthy.
I came upon a web page that linked thyroid problems to soya
intake and the conspiracy of soya marketed as a health food
when in fact it is only a toxic by-product of the vegetable
This was insane, after all, the health and fitness magazines
had said nothing about soya being harmful.
I visited a herbalist who was diagnosed with thyroid cancer
in 1985. She informed me that soya was the culprit. She had
a hysterectomy due to cysts and other uterine problems. A
few months later another acquaintance who had consumed soya
came down with thyroid cancer. A girl in England I met through
the internet in a thyroid cancer forum had just undergone
surgery and she was only 19.
What was going on?
Breast cancer is linked to estrogen. What mimics estrogen
in the female body, SOYA!
But I never suspected soya because until now I never once
found a single article that stated soya could be dangerous.
Women who took soya prior to thyroid problems will continue
to take it after if they are not aware of what soya actually
does, what it contains and how it reacts in the female body.
I think this is the reason that women with thyroid cancer
often develop breast cancer later.
My co-worker is big into soya and I see her losing hair and
gaining weight despite a walking workout during her break
and after work, and apples and oranges for lunch. She just
had cysts removed from her uterus too. I warn her to stay
off soya. I refer her to websites but evening news on all
four networks, women will suffer. Since the thyroidectomy
I do not touch soya, haven't for two years.
Dear readers, please use my story in any way you can. There
are so many young girls who are consuming soya because they
think they are taking care of themselves, and women taking
soya because they want to be healthy. It is so unfair that
the information about the dangers of soya isn't more widely
circulated. It is sad. There are many out there who feel this
way and it is a terrible blow when you realize you are not
as healthy as you thought and that the information that you
depended on was wrong.
Here are a couple of official rulings about soy that are rather
WITHDRAWS SOY/CANCER HEALTH CLAIM PETITION!
confirmed on October 4, 2005that the Solae Company has withdrawn
its petition for a soy protein and cancer health claim. Had
this health claim been approved, it would have doubled the
sales of soy protein in the USA, bringing huge profits to
the soy industry while putting American men, women and children
represents a major blow to the soy industry," says Kaayla
T. Daniel, PhD, author of The Whole Soy Story: The Dark Side
of America's Favorite Health Food. "The FDA advised Solae
on at least one occasion that it had not convincingly established
that soy can prevent cancer and that it had failed to counter
massive evidence that soy can cause, contribute to or accelerate
joined the Weston Price Foundation to present much of the
scientific evidence against soy that led to the FDA's questions
and to Solae's withdrawal. The Weston A. Price Foundation
has been a leader in alerting the public to the fact that
soy protein and soy oil in the food supply have been linked
to digestive distress, thyroid damage, reproductive problems,
infertility, ADD/ADHD, dementia, heart disease and cancer.
first petitioned the FDA for a health claim in February 2004.
Food manufacturers put health claims approved by the FDA on
labels and packages to increase sales because they encourage
consumers to make "healthier" purchases. The FDA
had hoped to announce its final decision on October 23, 2005.
June 2004 and April 2005, the Weston A. Price Foundation submitted
three detailed and heavily referenced documents to the FDA
that refuted the claims for soy and cancer made by the Solae
Company, a joint venture of Dupont and Bunge. This summer
the Foundation drew the FDA's attention to a July 2005 health
advisory issued by the Israeli Health Ministry that warned
that soy infant formula should not be given to infants, that
children should be fed soy foods no more than once per day
to a maximum of three times per week and that adults should
exercise caution because of increased risk of breast cancer
and adverse effects on fertility.
the Foundation spearheaded a write-in campaign to the FDA
earlier this year that brought in over 1,000 comments by our
members requesting the FDA to not approve Solae's petition.
You are all to congratulated for this fine effort.
petition to the FDA, Solae contended that a qualified health
claim was warranted because of "substantial scientific
agreement" among experts that soy protein reduces the
risk of breast, prostate and colon cancers. "No such
consensus exists," says Dr. Daniel. "Scientists
at the FDA's own Center for Toxicological Research have warned
of soy protein's carcinogenic potential and of the health
dangers of excess soy-food consumption. We showed the FDA
that Solae was highly selective in its choice of evidence
and biased in its interpretations. We reported on the fact
that they had omitted many studies proving soy to be ineffective
in preventing cancer, emphasized favorable outcomes in studies
with mixed results and excused the results of the few unfavorable
studies that they included to give the illusion of balance.
Most importantly, we drew the FDA's attention to the fact
that Solae excluded many studies showing that soy protein
can cause and accelerate the growth of cancer, particularly
to the recent soy warning issued by the Israeli Health Ministry,
expert scientists with the British Committee on Toxicity,
Swiss Federal Health Service and other government agencies
have all expressed concern about soy's potential to disrupt
the digestive, immune and neuroendocrine systems of the human
body and its role in rising rates of infertility, hypothyroidism
and some types of cancer including thyroid and pancreatic
also highly allergenic. Most experts now place soy protein
among the top eight allergens, and some rate it in the top
six or even top four. The Swedish Health Ministry has warned
that allergic reactions to soy are increasingly common, ranging
from mild to life threatening, and that fatalities have been
are finally starting to hear that soy is not a 'miracle food,'"
says Dr. Daniel. "More and more expert scientists are
issuing warnings about soy. The FDA made a big mistake in
1999 when it kowtowed to the soy industry and allowed a soy-and-heart-disease
health claim. Today's FDA is under intense scrutiny because
of the Vioxx debacle and could not afford to approve an unfounded
soy-prevents-cancer health claim. Solae withdrew its petition
because it knew that its science was unconvincing and that
the FDA had no choice but to turn them down. The bottom line
is that soy does not prevent cancer."
And in Israel:
manufacturers of soya products were rattled by the recommendation
issued by the country's health ministry that consumption of
soya products be limited in young children and avoided, if
possible, in infants. After a year's work, a committee of
experts also advised that adults who eat soya products do
so in moderation, pending authoritative future studies. Although
research showing possible harm;a higher risk of cancer, male
infertility, or other problems from soya is based on animal
or retrospective human studies, the committee of 13 issued
recommendations based on the precautionary principle.
phytoestrogens that may have some of the effects of the human
hormone if consumed in large quantities. Soya consumption
is high in Israel, and use of soya based baby formula is among
the world's highest per capita. Nevertheless, the ministry
decided not to prohibit the sale of soya based formula without
a doctor's prescription, which is already required in New
Zealand and Australia.
soya use in Israel is due to a number of reasons, most prominently
kosher food practices. Jewish law and tradition forbid the
mixing of milk and meat products, dishes, and cutlery, and
after eating meat individuals must wait some six hours before
ingesting dairy foods. Although this interval is not required
of babies, many ultraorthodox mothers observe it anyway, and
those who do not breastfeed prefer soya based rather than
cow's milk formulas so bottles are not on the table during
need for soya based formula due to allergy to cow's milk based
formula is negligible. Since soya provides cheaper protein
than meat, it is widely served in various forms, especially
in day care centres that are spared from using separate dishes
and cutlery. Soya burgers made from reconstituted flakes and
other forms, many of them developed by Israeli companies,
as well as tofu and misu, are popular among health conscious
don't know the long term effects on health of large amounts,
so we are urging moderation," said Dorit Nitzan Kaluski,
director of the health ministry's food and nutrition service
who was a committee member. "We want to be careful. And
while it is easy to identify soya products, there is much
more soya added to foods such as breads, cakes, cookies, and
will monitor the thyroxine concentrations in infants and toddlers
who have hypothyroidism who drink soya based formula or soya
foods. And women with breast cancer or a high risk of it will
be advised to consult their doctors about soya in their diets.
Kaluski said that to avoid pressure from soya food firms,
the committee did not inform them in advance, but within a
day of the report's release, she received at least one lawyer's
letter and numerous requests for information. She expects
lawsuits are on the way.