It has been discussed lately in allergist office magazines that MSG is not an
allergen. It was never considered one. What most people don't realize is the
difference between food allergy and food intolerance
or sensitivity.
MSG Sensitivity
Unlike food allergies which affect only certain individuals (only 2% - 5% of the
population), and involve an antibody response of the immune system, food sensitivities
affect many more people. You can be allergic to carrots and have an immune response to
them, and someone else may have absolutely no immune response at all. Sensitivities are a
different matter. There are no antibodies involved
and in the case of MSG, the free glutamic acid in
it acts in us all in the same way. It is a
neurotransmitter - it causes nerve cells to fire. The reason MSG is used by food companies
is because in the average human it stimulates the nerve cells in your mouth, as well as
the brain. It targets the centers of hunger and taste and
smell. If it only worked in 2% of the population, there wouldn't be any money in it.
It is basically a drug like alcohol or caffeine. However, the sensitivity response of any
individual is simply a matter of degree.
MSG and the Immune System
Unfortunately, MSG also may affect the allergy response as well although it may not
initiate it. According to new research from Johns Hopkins, the immune system is disturbed
by nervous system over-stimulation. This is a problem because MSG is a nervous system
excitatory neurotransmitter. Glutamate triggers nerve cells to fire. See the
following link for info regarding this latest research:
http://www.hopkinsmedicine.org/press/2000/MAY/000518.HTM
The following is a link to information about glutamate
increasing histamine by 150%:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1381677&dopt=Abstract
This makes the argument by MSG sellers and their spokespersons about MSG
being blamed for deadly reactions in restaurants actually caused by true allergens i.e.
seafood, peanuts, etc. disingenuous. There are attempts by the industry to
place the blame squarely on histamine alone as the culprit in these deaths.
Consider: If the presence of glutamate triggers a more
severe histamine response than otherwise would be suffered by the unwitting allergic
victim, perhaps MSG did not kill the victim directly, but was actually an
accomplice. Perhaps the individual would have survived had MSG not also been in the
offending food.
One has to conclude that if MSG exacerbates an already-occurring
allergic reaction, then it would appear to be an extremely dangerous unnecessary food
additive to place in restaurant meal.