In his Guest Editorial of October
2000 in the Townsend Letter, Mr. Bill Sardi expresses surprise
that the "greatest criticism of soy has come from natural
health advocates." Yet most of the soy-based products on
the market today can hardly be called "natural" foods.
They are produced in factories at high temperatures and pressures
and with the help of a variety of chemicals. The soybeans themselves
are grown on huge corporate farms, most of which use toxic pesticides
and herbicides.
The fact that these products can be labeled "natural"
only demonstrates the power and duplicity of soy interests in
America. Dr. Zava is one of many honest scientists who have
read the literature and discovered that soy contains:
iodine blockers that interfere with normal thyroid function
Mr. Sardi says these characterizations are unfair and inaccurate.
Like Dr. Zava, we do not repeat "claims" that soy
contains antinutrients and toxins; we quote the scientific literature.
Propaganda is "the systemic propagation of a given doctrine
or of allegations reflecting its views and interests; material
disseminated by the advocates of a doctrine."
The promotion of soy as a miracle food has been both systematic
and reflective of the doctrine of the food industry-that imitation
foods are good for us and traditional foods are unhealthy.
The soy campaign is, in fact,
a case study in the use of propaganda to promote commercial
interests.
Mr. Sardi misquotes us frequently. We stated that soy was not
considered fit to eat in Asia a few centuries ago (not a few
decades ago); we did not "acknowledge that Asians consume
30 times more soy than North Americans." We pointed out
studies showing that soy consumption in Asia is actually much
lower than claimed-averaging 10 grams per person, less than
two teaspoons.
He does not seem to understand our argument that if soy is
given as the reason Asians have lower rates of breast, prostate
and colon cancer (simply because Asians supposedly eat large
amounts of soy), then the same logic requires us to blame high
rates of cancers of the esophagus, stomach, thyroid, pancreas
and liver in Asian countries on consumption of soy.
The truth is that we don't know exactly why Asian countries
have certain types of cancers and western countries have other
types. Eastern types of cancers have been attributed to many
factors, of which soy consumption is one, but to claim that
soy consumption is associated with lower rates of certain types
of cancers while neglecting to mention that soy is also associated
with higher rates of certain types of cancer is typical of industry
dishonesty.
Sardi acknowledges that Asians have higher rates of pancreatic
cancers in one paragraph, but states that populations that consume
high levels of soy exhibit decreased rates of pancreatic cancer
in another. We are confused.
Messina did indeed omit the Rackis study in his "exhaustive"
survey. In fact, Messina did not include any animal studies
on pancreatic effects. The Rackis study showed not only enlargement
of the pancreas but also precancerous changes. And why the double
standard? Why is it appropriate to use rats prone to develop
breast cancer in experiments with soy, but not rats prone to
demonstrate disturbances in the pancreas?
It is standard scientific practice to use rats bred to react
in specific ways in order to study effects over short periods
of time. Normal rat chow did not cause pancreatic changes in
sensitive rats-only rat chow based on soy.
Birds don't eat soy, says Sardi. They know better. The Jameses
should have known that soy is not appropriate for birds (something
that would come as a surprise to the chicken industry.) The
Jameses trusted the literature that came with the product, which
stated that soy was an excellent food for birds. They also trusted
the claims made for soy infant formula, that soy was "better
than breast milk."
They should have known that
soy was not an appropriate food for humans,
particularly for babies and so should Mr. Sardi and all the
others out there who continue to provide glib assurances that
soy formula is a good substitute for milk-based formula.
The James learned a terrible lesson the hard way-that we should
not trust claims for commercial food products, especially when
these claims are too good to be true. In the absence of animal
instinct, it's important to be skeptical. "Scientists cannot
infer that animal data applies to humans," says Sardi.
But they do it all the time, especially when the data show
protective effects. Only when the studies are negative do scientists
get reprimanded for using them. Onward with the double standard.
It is axiomatic that when a chemical carcinogen is definitely
active in one or more animal models, it can be stated with certitude
that certain individuals of Homo sapiens would be at risk.
Soy proponents don't want the
public to know that phytoestrogens can induce tumors in several
different species of animals.
The younger the animal, the more susceptible it is to the action
of plant-based estrogens, as it frequently is to other carcinogens.
Sardi objects to some of our references.
One of them-Natural Health News published by L & H Vitamin
Company- was given as an example of promotional advertising,
which in this case claimed that soy could prevent cancer. He
complains of a missing citation, number 58, but there is no
missing citation. It is published on the website and was published
in the Townsend Letter.
Another criticism is that the average published date of our
references is 13 years old. We were not aware that averaging
publication dates was a valid method for assessing studies and
reports. Nevertheless, one of the aims of our article was to
show that studies indicating soy toxicity date back as far as
fifty to sixty years, especially studies showing adverse affects
on the thyroid gland. (Goitrogenic components have been confirmed
very recently by Divi and Doerges.)
Much good scientific work was done in past decades and it is
work that can be depended upon because it took place before
the soy industry began funding university research.
We hope that citation of the
following recent studies will make our "average published
date" more acceptable:
A study from Cornell University, published in the Journal of
the American College of Nutrition, 1986, which found that children
who develop diabetes mellitus were twice as likely to have been
fed soy.
A November 1994 warning published in Pediatrics in which the
Nutrition Committee of the American Academy of Pediatrics advised
against the use of soy formulas due to the diabetes risk. These
warnings have been neglected ever since it was reported that
the AAP accepted a multi-dollar donation from the Infant Formula
Council for their new headquarters building outside Chicago.
A 1994 article by Lonnerdal published in Acta Paediatr summarizing
the reduced bioavailability of trace minerals due to high phytic
acid content in soy infant formula; and high levels of manganese
in soy formula compared to cows milk formula and breast milk.
Excessive intake of manganese is linked to problems with the
central nervous system.
A 1996 report published in the German magazine Klin Padiatr
describing the development of hypocalcemic tetany in an infant
fed soy formula.
Two 1997 studies published in Nutrition and Cancer. One found
that phytoestrogens at levels close to probable levels in humans
stimulate cellular changes leading to breast cancer; the other
found that dietary soy suppressed enzymes protective of breast
cancer in mice.
A 1998 study published in the American Journal of Clinical
Nutrition further confirming that soy-protein supplementation
stimulates cell proliferation in human breast tissue.
A 1998 study published in Cancer Research which found that
dietary genistein enhances the growth of mammary gland tumors
in mice.
A 1998 study by Nagata and others published in the Journal
of Nutrition which gives daily consumption of tofu in Japan's
Gifu prefecture as less than 1 gram per day.
A 1998 study published in Toxicology and Industrial Health
indicating the phytoestrogens are potential endocrine disrupters
in males.
A March 12, 1999 Daily Express article with the headline "Soy
Allergy/Adverse Effect Rates Skyrocket - Monsanto's Roundup-Ready
Soy Blamed"
A 1999 study at the Clinical Research Center at MIT, published
in the Proceedings of the Annual Meeting of the Pacific Coast
Reproductive Society which found that estrogens in soy had no
effect on menopausal symptoms such as hot flashes and night
sweats.
May 1999 and June 2000 studies published in Brain Research
indicating that phytoestrogens have adverse affects on brain
chemistry.
An April 2000 study published in Proceedings of the National
Academy of Science which found that flavonoids, especially genistein,
can cross the placenta and induce cell changes that lead to
infant leukemia.
An article published in Nutrition and Cancer 2000 which found
lower testosterone levels and higher estrogen levels in Japanese
men who consumed higher levels of soy foods.
Publication in the British Journal of Urology, January 2000,
of the study showing a five-time greater risk of delivering
a boy with hypospadias, a birth defect of the penis, in mothers
who ate a vegetarian diet during pregnancy. The researchers
attributed high rates of the birth defect to phytoestrogens
in soy products.
An April 2000 study published in Carcinogenesis found that
soy feeding stimulated the growth of rat thyroid with iodine
deficiency, partly through a pituitary-dependent pathway.
A June 2000 article in American Journal of Cardiology which
found that soy had no impact on lipid levels in healthy postmenopausal
women
Evidence that disturbing results were omitted from a 1994 study
presented to the FDA during the approval process for Roundup
Ready Soybeans. Researchers found that raw Roundup Ready meal
contained 27 percent more trypsin inhibitor and toasted Roundup
Ready meal contained 18 percent more trypsin inhibitor compared
to non-genetically manipulated controls.
The most serious concerns regarding
soy foods involve the use of soy infant formula.
Sardi cites a 1998 Nutrition Reviews article by K. O. Klein
of duPont Hospital for Children as proof that soy infant formulas
do no harm.
Yet in the article Klein notes that effects of isoflavones
on various animal species include hormonal changes, increased
uterine weight and infertility. " It is clear from the
literature," says Klein, "that different species and
different tissues are affected by isoflavones in markedly different
ways.
It is difficult to know which tissue, if any, are affected
in infants, and the variation among species makes extrapolation
to infants inappropriate." This is scientific double talk.
Scientists may be reluctant to extrapolate but parents would
certainly err on the side of caution if they knew that "isoflavones
affect different tissues in markedly different ways." Klein
says that medical literature provides "no evidence of endocrine
effects. . and no changes in timing of puberty."
But she makes no mention of the Puerto Rican study which found
that consumption of soy formula correlated strongly with early
maturation in girls.
Why would Dr. Klein leave out any reference to the Puerto Rican
study in her review? Is it because DuPont, owner of Protein
Technologies International, is the leading manufacturer of soy
protein isolate?
Or is it because her review was sponsored by the Infant Formula
Council? Or because Nutrition Reviews, which published her whitewash,
is funded by industry giants, including Pillsbury, Hershey Foods,
Kellogg, Roche, General Mills, Kraft, Campbell Soup, Monsanto,
Coca-Cola, Cargill, Heinz, Nabisco, Proctor and Gamble and Pepsi-Cola?
Soy can be implicated as a
probable cause in the current epidemic of learning disabilities
because it has similar effects in monkeys. Sardi is correct
in stating the 1997 Journal of Pediatrics article makes no
mention of soy. Neither does Time Magazine in their recent
article on early puberty in girls.
The Time article speculates that exogenous estrogens might
be the cause. Is it not appropriate to speculate that estrogens
in soy formula, which are not "reduced significantly by
their first pass through the liver" as Sardi claims but
end up in the blood of infants in huge amounts, might also be
a cause?
Perhaps it is the hormones in meat and milk, say the writers
of the article. But hormonal levels in these products are minuscule
compared to levels in soy formula. And in the Puerto Rican study,
consumption of milk was negatively correlated with early maturation,
which means that it might be protective.
We do not claim that Asians have lower rates of osteoporosis-it
is the soy supporters who make that claim. But if in fact they
do have lower rates of bone loss, it is much more likely due
to factors in the diet that are consumed in large amounts and
that provide vitamin D and calcium, such as bone broth, shrimp
and lard.
We are aware of new research indicating that consumption of
vitamin D is optimal at 4000 IU per day, not the RDA of 400
IU. This research is an excellent confirmation of the work of
Weston Price who found that the diets of healthy primitives
peoples had at least ten times more vitamin D than that of the
average American of his day. (Sunlight will not provide adequate
vitamin D unless a large portion of the skin is exposed during
the summer months or in tropical latitudes.)
The textbooks do indeed need to be rewritten to stress consumption
of vitamin-D-rich animal foods and to minimize consumption of
foods that increase our requirements for vitamin D-like soy.
Shrimp sauces and shrimp pastes used in Asia and Africa are
made from dried shrimp, hence very concentrated.
They are eaten daily, often at every meal and could be expected
to provide vitamin D in amounts greatly exceeding vitamin D
intake levels in the US. The vitamin D content of butter varies
with the feed of the animals. Butter from cows on green growing
grass is likely to provide far more vitamin D than butter from
cows in confinement. We advocate consumption of butter from
pasture-fed animals (and eggs, lard and other animal foods for
the same).
Townsend Letter April 2001 213:100-103