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Soy Neurotoxicity?

Survivor Survivor at Ground.Zero
Tue Oct 7 21:16:40 EST 2003


On Wed, 06 Aug 2003 21:02:14 -0400, Ian Goddard <igoddard at erols.mom>
wrote:

>FINDINGS MAY SUPPORT SOY-DEMENTIA CORRELATION IN MALES
>
>(c) 08/06/03 - Ian Williams Goddard
>
>In April 2000, Lon White and others reported a dose-dependent positive
>correlation between tofu consumption and brain atrophy in a large
>sample of men over several decades. [1] While correlation does not
>prove causation, study size and duration along with the robust
>dose-dependent relationship caused me, even as a vegetarian, to avoid
>tofu and other soy products.
>
(Snip!)
> 
>In closing, the findings of soy-induced BDNF reduction in male rat
>brain regions that are central to the onset of dementia, in addition
>to previous findings, [2] appear to provide compelling evidence of a
>possible causal mechanism that might explain the soy-dementia
>correlation reported by White et al. [1] Obviously further research is
>necessary before a clear picture emerges regarding the effects of
>long-term soy consumption on the brain. But in the meantime, my
>inclination is to play it safe and avoid soy.
>

I find this whole thread rather confused and confusing. 


1) Has anyone analyzed tofu, as opposed to other soybean products?

Assuming the research findings can be replicated by others, is the
problem due to tofu's soy content, to some other ingredient, or to
contaminants?

The New York Times reported about a year ago that a very high
proportion of "fresh" tofu sold in the NYC area had dangerously high
microbial counts, due to improper storage and distribution. For
example, many neighborhood ethnic food stores in NYC sold tofu in
brine in unrefrigerated containers.

Presumably most of the microbes were killed, if the tofu was
thoroughly cooked. I have no idea whether any of the microbes might
produce toxins or byproducts that could survive cooking. 


2) Soybean oil, lecithin, and other soy products are so widely used in
the food industry (in salad dressings, shortenings, breads and other
baked goods) that it seems hard to believe that the non-tofu control
groups in the research had not been consuming other soy products,
whether or not they knew it.  (Just check the ingredient labels of the
packaged foods in your kitchen pantry.) 


3) It is very likely, I think, that the tofu-consuming participants in
the study were also far more frequent consumers of other "odd" foods,
such as bean sprouts, seaweed, fermented soy sauce and miso, avocados,
etc. I suspect they might also have had a lower exposure to pesticides
and preservatives and consumed less coffee and caffeine. Without a
menu census we can only make guesses about consumption patterns,
habits, and quantities. Perhaps tofu is only a marker for other
consumption or lifestyle patterns.  


4) Phosphatidylserine is often recommended for early-stage memory
problems, such as those "I know the word; it's at the tip of my
tongue, but I can't recall it" phenomena.  

I'm told Phosphatidylserine has a history of use in Europe as a
treatment for Alzheimer's Disease as well, though I don't know the
research, if any, that supports this use. 

The point is this -- Phosphatidylserine is now derived, almost
exclusively, from soybeans and is often packaged with
Phosphatidylcholine, Phosphatidylethanolamine, and
Phosphatidylinositol, other soybean derivatives. 

(At one time Phosphatidylserine was derived from cow brains, but that
source is now considered risky, due to the occurrence of "mad cow"
disease.) 


So tofu from soybeans is bad, but Phosphatidylserine from soybeans
might be good? Seems premature to start avoiding all soy products. 


Anyone want to comment?

Thanks.

Survivor @ Ground.Zero




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