Soy's Thyroid Dangers

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Soy's Thyroid Dangers A Look at the Dangers of Soy to the Health of Your

Thyroid Related Information . " The Other Side of Soy " -- ABC News

Television, 20/20 Program

.. Soy Online Service

.. Soy Isoflavones: Panacea or Poison, from the Weston A. Price Foundation

.. " Tragedy and Hype, " The Third International Soy Symposium

 

 

 

by Mary J. Shomon

 

Health and nutrition magazines tout the benefits of soy as a cure-all for

women's health, hormonal problems, cancer prevention, weight loss, and many

other problems. The reality, however, is that promotion of soy may be more a

matter of business and marketing, rathan than recommendations based on sound

scientific evidence.

 

Isoflavones, the key components of soy that make them so potent as a posible

substitute for hormone replacement, mean that soy products, while touted as

foods and nutritional products -- often are used and act as like a hormonal

drug.

 

If you have a diagnosed or undiagnosed thyroid problem, or a history of

autoimmune disease, overconsumption of soy isoflavones can potentially

trigger a thyroid condition. Soy foods can worsen an existing diagnosed

thyroid problem in many people. In both cases the symptoms such as fatigue,

weight gain, and depression or moodiness are often overlooked and hard to

diagnose.

 

A recent study found that as millions of Americans -- perhaps as many as

more than 10 million -- have an undiagnosed thyroid condition. The vast

majority of thyroid patients are women over 40. This is the same group that,

responding to marketing claims that promote soy as helping to prevent breast

cancer, reducing the risk of high cholesterol or heart disease, or as a

treatment for symptoms of menopause, are turning to soy foods and isoflavone

supplements in vast numbers.

 

Here is more information regarding soy and its relationship to the thyroid.

 

FDA's Soy Experts Speak Out Against Soy

 

" there is abundant evidence that some of the isoflavones found in soy,

including genistein and equol, a metabolize of daidzen, demonstrate toxicity

in estrogen sensitive tissues and in the thyroid. This is true for a number

of species, including humans.

 

Additionally, isoflavones are inhibitors of the thyroid peroxidase which

makes T3 and T4. Inhibition can be expected to generate thyroid

abnormalities, including goiter and autoimmune thyroiditis. There exists a

significant body of animal data that demonstrates goitrogenic and even

carcinogenic effects of soy products. Moreover, there are significant

reports of goitrogenic effects from soy consumption in human infants and

adults. " Official Letter of Protest to the FDA Letter of protest from

researchers Daniel Doerge and Daniel Sheehan, two of the Food and Drug

Administration's (FDA) key experts on soy, to the FDA, protesting the health

claims approved by the FDA on soy products

 

America's Foremost Alternative Doctor Warns Re: Soy

 

America's leading alternative doctor, Dr. Andrew Weil, has said about soy,

at his Ask Dr. Weil website " .you're unlikely to get too many isoflavones as

a result of adding soy foods to your diet -- but you probably will take in

too much if you take soy supplements in pill form. At this point, I can only

recommend that you avoid soy supplements entirely. " Study Shows That Too Much

Tofu Induces Brain Aging

 

>From the Honolulu Star-Bulletin " A Hawaii study shows a significant

statistical relationship between two or more servings of tofu a week and

'accelerated brain aging' and even an association with Alzheimer's disease,

says Dr. Lon White. " " ...these are not nutrients. They are drugs. They will

have some benefits and some negative things. " Don't Go Overboard With the Soy

Foods!

 

David Zava, Ph.D., a biochemist and an experienced breast cancer researcher

stated in an interview: " In studying the literature on soy I found there are

about five types of plant chemicals [antinutrients] in the soybean that can

be toxic to humans if they are not removed by special processing. the fifth

antinutrient in soybeans is called a goitrogen. This is a chemical that

latches on to iodine, preventing it from absorbing into the body from the

gastrointestinal tract. Iodine is needed to make thyroid hormone. Low

thyroid function has been associated with poor brain development. Anyone who

has been deficient in thyroid hormone understands quite well what impact

this can have on normal brain function, especially at a time in life as we

grow older and " fuzzy thinking " creeps into our vocabulary. " North American

Menopause Society Won't Endorse Soy Products

 

In a press statement, the North American Menopause Society has said: " Our

review found that scientific data are inconclusive regarding whether the

observed health effects in humans are attributable to isoflavones alone or

to isoflavones plus other components in whole foods. women may wish to

consume whole foods that contain isoflavones, especially for potential

cardiovascular benefits. However, scientific data supporting the use of

isoflavones for hot flashes are conflicting, and inadequate data exist to

evaluate their effect on breast and other female cancers, bone mass and

vaginal dryness. Our evaluation also pointed out that a level of caution

needs to be observed, especially in the use of isoflavone supplements,

powders and pills.More studies documenting benefits and safety need to be

conducted.''Research Shows Soy's Effects

 

 

American Journal of Clinical Nutrition, Vol 68, 1431S-1435S, " Effects of

soy-protein supplementation on epithelial proliferation in the

histologically normal human breast " -- Study showed that short-term use of

dietary soy stimulated breast cell proliferation, which can increase the

risk of breast cancer.

Anti-thyroid isoflavones from soybean -- November 1997 article from

Biochem Pharmacol in which " it was observed that an . extract of soybeans

contains compounds that inhibit thyroid peroxidase- (TPO) catalyzed

reactions essential to thyroid hormone synthesis. "

Breast and soy-formula feedings in early infancy and the prevalence of

autoimmune thyroid disease in children. -- April 1998 article from the J Am

Coll Nutr. that documents the association of soy formula feedings in infancy

and autoimmune thyroid disease.

Leading Expert Warns of Soy-Thyroid Connection in Bestselling Book

 

In the bestselling book Living Well With Hypothyroidism: What Your Doctor

Doesn't Tell You . . . That You Need to Know, leading soy expert Dr. Mike

Fitzpatrick was profiled. " Dr. Mike Fitzpatrick is an environmental

scientist and phytoestrogen researcher who has extensively researched the

issue of soy formulas, and the impact of soy consumption on thyroid

function. Dr. Fitzpatrick introduced me to a little-known fact that can have

substantial impact on people with hypothyroidism and the population in

general -- overconsumption of soy products has the potential to impair

thyroid function. Dr. Fitzpatrick is so concerned that he is calling for soy

formula manufacturers to remove the isoflavones -- the agents that are most

active against the thyroid -- from their products. .. There are also

concerns for adult consumption of soy products. One UK study involving

premenopausal women gave 60 grams of soy protein per day for one month. This

was found to disrupt the menstrual cycle, with the effects of the

isoflavones continuing for a full three months after stopping the soy in the

diet. Another study found that intake of soy over a long period causes

enlargement of the thyroid and suppresses thyroid function. Isoflavones are

also known to modify fertility and change sex hormone status, and to have

serious health effects -- including infertility, thyroid disease or liver

disease -- on a number of mammals. Dr. Fitzpatrick believes that people with

hypothyroidism should seriously consider avoiding soy products, and predicts

the current promotion of soy as a health food will result in an increase in

thyroid disorders. " Soy Researcher is Even 'Very Concerned'

 

" 'There's a tendency in our culture to think if a little is good, then a

lot's better,' says Mary Anthony, a soy researcher at Wake Forest University

School of Medicine in Winston-Salem, N.C. 'But I personally am very

concerned about isoflavone pills and soy protein supplemented with extra

isoflavones.' Isoflavones, after all, seem to act like hormones or drugs in

our body--even if for regulatory purposes they are classified as nutritional

supplements. " (From " In Light of Troubling Study on Soy, Moderation Seen as

Key, " LA Times , Monday, March 27, 2000)

 

 

 

 

 

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