Soy

[Guest guest]

Why are we bringing religion on to this list? Would Dr. Mercola be more valid

if he was a fundamentalist muslim or a buddha or a jewish person?

I personally have had some very unfortunate experiences with soy

and a medication that I have to take...

donna

 

In a message dated 01/20/11 4:05:15 AM, mcpheej writes:

 

<<

> develop a feel about who can be trusted and who not. Generally

> osteopaths, like him, do not fall into the trustworthy category. I

> become even more suspicious when they have religious leanings - this guy

> seems to be a fundamentalist Christian. Nothing wrong with that but >>

[Guest guest]

Morton Bodanis wrote:

 

> When I have a problem accepting information, I ask Dr. Joe Schwarcz for his

> opinion. He is a professor of Chemistry at McGill University, Montreal,

> Canada, teacher at Vanier College, author of two current best-selling books

> on science, frequent guest on the Discovery channel, weekly guest on CJAD

> radio call-in show, writes a weekly in the Gazette, a Montreal daily, will

> answer email, etc...

 

> So when I read the following, which I could not evaluate, I asked him to.

> Following the posting quote is his response, put into perspective. Sorry if

> this is becoming long.

 

 

(Txt) Soybean implicated in goiter & also inhibits

thyroid -NATIONAL LIBRARY OF MEDICINE

Fri, 16 Nov 2001 21:45:02 -0800

Gettingwell

 

Entrez-PubMedSoybean implicated in goiter & also inhibits

thyroid - NATIONAL LIBRARY OF MEDICINE

 

http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=9464451 & form=6 & db=m & Dopt\

=b

 

Anti-thyroid isoflavones from soybean: isolation, characterization, and

mechanisms of action.

Divi RL, Chang HC, Doerge DR.

National Center for Toxicological Research, Jefferson, AR 72079, USA.

 

The soybean has been implicated in diet-induced goiter by many studies. The

extensive consumption of soy products in infant formulas and in vegetarian

diets makes it essential to define the goitrogenic potential.

In this report, it was observed that an acidic methanolic extract of soybeans

contains compounds that inhibit thyroid peroxidase- (TPO) catalyzed reactions

essential to thyroid hormone synthesis. Analysis of the soybean extract using

HPLC, UV-VIS spectrophotometry, and LC-MS led to identification of the

isoflavones genistein and daidzein as major components by direct comparison

with authentic standard reference isoflavones. HPLC fractionation and

enzymatic assay of the soybean extract showed that the components responsible

for inhibition of TPO-catalyzed reactions coeluted with daidzein and

genistein. In the presence of iodide ion, genistein and

daidzein blocked TPO-catalyzed tyrosine iodination by acting as alternate

substrates, yielding mono-, di-, and triiodoisoflavones. Genistein also

inhibited thyroxine synthesis using iodinated casein or human goiter

thyroglobulin as substrates for the coupling reaction. Incubation of either

isoflavone with TPO in the presence of H2O2 caused irreversible inactivation

of the enzyme; however, the presence of iodide ion in the incubations

completely abolished the inactivation. The IC50 values for inhibition of

TPO-catalyzed reactions by genistein and daidzein were ca. 1-10 microM,

concentrations that approach the total isoflavone levels (ca. 1 microM)

previously measured in plasma from humans consuming soy products. Because

inhibition of thyroid hormone synthesis can induce goiter and thyroid

neoplasia in rodents, delineation of anti-thyroid mechanisms for soy

isoflavones may be important for extrapolating goitrogenic hazards identified

in chronic rodent bioassays to humans consuming soy products.

 

PMID: 9464451 [PubMed - indexed for MEDLINE]

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sparc-sun-solaris2.8 Nov 15 2001 10:41:10