Dear WDDTY:

Re a letter in your July issue concerning a possible link between monosodium glutamate (MSG) and excitotoxins:

Monosodium glutamate is the sodium salt of glutamic acid and has a long history of safe use as a means of enhancing food flavour, along with other various forms of glutamate such as soy sauce.

Glutamate is one of the most abundant amino acids in the human body and is present in virtally all protein-containing foods. Glutamate in the brain does not, however, originate from glutamate in the food we eat.

Dietary ingestion of glutamate is separate from brain processes involving glutamate. It is metabolized in the same way, whether intake is from meat, vegetables, dairy products or through monosodium glutamate added to food preparation.

The European Union's scientific Commmittee for Food and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) both gave monosodium glutamate an Acceptable Daily Intake of "not specified," their most favourable classification. In the United States, it is listed as a typical example of a Generally Recognized as Safe (GRAS) substance, along with pepper, sugar, vinegar and baking powder. Hannah Chadwick, The Glutamate Information Service........

WDDTY replies:

Recently, during an otherwise pleasant Chinese meal, my temples began aching, my husband's jaw began locking and my daughter began complaining of a headache. We nearly had to leave. We have a similar reaction everytime we eat foods containing MSG.

The funny thing is, we don't seem to have that problem when we eat protein, dairy products or anything else that you say naturally contains glutamate. I often wonder what exactly in my body is being "enhanced" when my head feels like it is being crushed by a vice.

Thanks to Dee Adams who sent us an article from the current Foresight magazine about the book we referred to. Its view is that excitotoxin food additives, which include asparatame and hydrolized vegetable protein, besides MSG, are particularly dangerous to developing fetuses, who lack a complete blood-brain barrier.

It should be noted manufacturers are allowed to disguise the presence of additives like these in foods. They are added to baby food in the form of "caseinate", stock or simply "flavourings" and as "chelating amino acids" in supplements.