From: wcsbeau@alfred.carleton.ca (OPIRG)
Subject: Re: Is MSG sensitivity superstition?
Keywords: MSG, Glu
Organization: Carleton University, Ottawa, Canada
Lines: 143

In article <1993Apr17.202011.21443@spdcc.com> dyer@spdcc.com (Steve Dyer) writes:
>In article <1993Apr17.184435.19725@cunews.carleton.ca> wcsbeau@alfred.carleton.ca (OPIRG) writes:
>
>There has been NO hard info provided about MSG making people ill.
>That's the point, after all.

Why don't you just look it up in the Merk? Or check out the medical dictionary
cite which a doctor mentioned earlier in this thread?


>
>That's because these "peer-reviewed" studies are not addressing
>the effects of MSG in people, they're looking at animal models.
>You can't walk away from this and start ranting about gloom and
>doom as if there were any documented deleterious health effects
>demonstrated in humans.  Note that I wouldn't have any argument
>with a statement like "noting that animal administration has pro-
>duced the following [blah, blah], we must be careful about its
>use in humans."  This is precisely NOT what you said.

Among others, see Olney's  "Excitotoxic Food Aditives - Relevance of
Animal Studies to Human Safety" (1982) Neurobehav. Toxicol. Teratol.
vol 6: 455-462.

I'm sure PETA would love to hear your arguments.

>>Tests have been done on Rhesus monkeys, as well. I have never seen a
>>study where the mode of administration was intra-ventricular.  The Glu
>>and Asp were administered orally. Some studies used IV and SC.
>>Intra-ventricular is not a normal admin. method for food tox. studies,
>>for obvious reasons. You must not have read the peer-reviewed works
>>that I referred to or you would never have come up with this brain
>>injection bunk.
>
>It most certainly is for neurotoxicology.  You know, studies of
>glutamate involve more than "food science".

Whose talking about "food science"? What is this comment supposed to
mean? *Neurotoxicology and Tratology*, *Brain Research*, *Nature*,
*Progress in Brain Research*: all fine food science journals. ;-)

>>Pardon me, but where are you getting this from? Have you read the
>>journals? Have you done a thorough literature search?
>
>So, point us to the studies in humans, please.  I'm familiar with
>the literature, and I've never seen any which relate at all to
>Olney's work in animals and the effects of glutamate on neurons.

Then you would know that Olney himself has casually  referred to
"Chinese Restaurant Syndrome" in a few articles. Why don't *you* point
us to some studies? Maybe then this exchange could be productive.

>>The point is exceeding the window. Of course, they're amino acids.
>>Note that people with PKU cannot tolerate any phenylalanine.
>
>Well, actually, they HAVE to tolerate some phenylalanine; it's a
>essential amino acid.  They just try to get as little as is healthy
>without producing dangerous levels of phenylalanine and its metabolites
>in the blood.

They're unable to metabolise it.

>>Olney's research compared infant human diets. Specifically, the amount
>>of freely available Glu in mother's milk versus commercial baby foods,
>>vs. typical lunch items from the Standard American Diet such as packaged
>>soup mixes. He found that one could exceed the projected safety margin
>>for infant humans by at least four-fold in a single meal of processed
>>foods. Mother's milk was well below the effective dose.
>
>Goodness, I'm not saying that it's good to feed infants a lot of
>glutamate-supplemented foods.  It's just that this "projected safety
>margin" is a construct derived from animal models and given that,
>you can "prove" anything you like.  We're talking prudent policy in
>infant nutrition here, yet you're misrepresenting it as received wisdom.

Who said anything about 'received wisdom'? There is no question that
orally administered doses of MSG are capable of destroying nearly all
neurons in the arcuate nucleus of the hypothalamus and the median
eminence. These areas are responsible for the production of
hormones critical to normal neuroendocrine function and the normal
development of the vertabrate organism. Humans are vertebrates. Now
what, pray tell, do you think will happen when the area of the brain
necessary for the normal rhythm of gonadotropin release is missing?
Are you trying to say that humans have no need of their pituitary,
ANH, and ME, of that part of the brain that is responsible for
controlling the realease (albeit indirectly) of estradiol and testosterone? 

How do you expect anyone to do the studies on this? It's unethical to
"sacrifice" humans to check out what effects chronic, acute, etc doses
of these compounds are having on the brain tissue in humans.  The food
industry knows this. That's why the animal model is used in medicine
and psych.  If you're talking about straight sensitivity, it would be
useful to define the term.  There are plenty of studies on
psychoneuroimmunology showing the link between attitude and
physiology.

I suspect we may be arguing about separate things; *only* adult sensitivities
(You), and late-occuring sequelae of childhood ingestion and its
implication for adults (me).  Certainly
the doses for excitotoxicity in adults are considerably larger than
for the young, but the additivity of Glu and Asp, and their copious
and increased presence in modern processed foods (jointly), and their
hidden presence in HVP, necessitates extreme caution. Why would anyone
want to eat compounds which have been shown to markedly perturb the
endocrine system in adults?  The main point is *blood levels*
attained, and oral doses would likely have to be greater than SC. 

>>Between who? Over what? I would be most interested in seeing you
>>provide peer-reviewed non-food-industry-funded citations to articles
>>disputing that MSG has no effects whatsoever. 
>
>You mean "asserting".  You're being intellectually dishonest (or just
>plain confused), because you're conflating reports which do not necessarily
>have anything to do with each other.  Olney's reports would argue a potential
>for problems in human infants, but that's not to say that this says anything
>whatsoever about the use of MSG in most foods, nor does he provide any
>studies in humans which indicate any deleterious effects (for obvious
>reasons.)  It says nothing about MSG's contribtion to the phenomenon
>of the "Chinese Restaurant Syndrome".  It says nothing about the frequent
>inability to replicate anecdotal reports of MSG sensitivity in the lab.

Olney's work provides a putative causal mechanism for some
sensitivities. Terry, Epelbaum and Martin have shown that orally
administered MSG causes changes in normal gonadotropic hormone
fluctutations in adults. Glu also was found to induce immediate and persistant
supression of rhythmic GH secretion, and to induce rapid and transient
release of prolactin in adults chronically exposed to MSG. GH is
responsible not only for control of growth during development, but
also converts glycogen into glucose. Could this be the cause of
headaches? I don't know.

>>>dyer@ursa-major.spdcc.com 
>>Hmm. ".com". Why am I not surprised?
>>- Dianne Murray   wcsbeau@ccs.carleton.ca
>
>Probably one of the dumber remarks you've made.

If you had read Olney's review article, especially the remarks I
already quoted in an earlier post, you would know to what I was
alluding. May I ask exactly for whom you do computer consulting? :-)

