Dr. George J. Georgiou, Ph.D.
BASIC FACTS ABOUT MSG
MSG-sensitivity is a sensitivity to free glutamic acid that occurs in food as a consequence of manufacture. All protein contains glutamic acid bound in it, but only when glutamic acid has been freed from protein before it is eaten do people have MSG-sensitivity reactions, provided that they ingest amounts that exceed their individual tolerance levels. Some unadulterated protein may have minute amounts of free glutamic acid associated with it, but MSG-sensitive people do not generally report adverse reactions following ingestion of unadulterated protein. Any free glutamic acid freed from protein during processing can cause MSG reactions. The source of the hydrolyzed protein (soy, corn, etc.) appears to be irrelevant.
MSG is manufactured through a process of protein hydrolysis, wherein glutamic acid is freed from protein through fermentation or use of chemicals or enzymes. MSG is also manufactured by what is referred to as a fermentation process wherein bacteria are grown aerobically in a liquid nutrient medium. The bacteria have the ability to excrete glutamic acid they synthesize outside of their cell membrane into the liquid nutrient medium in which they are grown. The glutamic acid is then separated from the fermentation broth by filtration, concentration, acidification, and crystallization, and converted to its monosodium salt.(1) With some exceptions, the FDA requires that ingredients -- MSG-containing ingredients included -- must be called by their common or usual names. The name "monosodium glutamate" is reserved for the ingredient that is a 99% pure combination of glutamic acid and sodium. The names of most other MSG-containing ingredients won't give consumers even a clue to the fact that the ingredients contain MSG.
"Monosodium glutamate," "monopotassium glutamate," "autolyzed yeast," "hydrolyzed soy protein," and "sodium caseinate," are examples of ingredients that always contain MSG.
Under certain circumstances, hydrolyzed protein products may be used as ingredients in other products without even mention of the original hydrolyzed protein products. For example, "hydrolyzed soy protein," when used in "flavoring(s)," "natural flavoring(s)," and "natural flavor(s)," does not have to be mentioned on product labels when the food processor claims that the hydrolyzed protein is being used for purposes other than flavoring. In addition, MSG-containing products such as broth, bouillon, and stock, when used as ingredients in other products, do not have to disclose their MSG-containing components--not even by their common or usual names.
Use of MSG in food continues to grow. MSG is found in most soups, salad dressings, processed meats, frozen entrees, ice cream, and frozen yogurt; in some crackers, bread, canned tuna; and very often in "low fat" foods to make up for flavor lost when fat is reduced or eliminated.
THE FIRST EVIDENCE OF TOXICITY
The first published report of a reaction to monosodium glutamate appeared in 1968 when Robert Ho Man Kwok, M.D., who had emigrated from China, reported that although he never had the problem in China, about 20 minutes into a meal at certain Chinese restaurants, he suffered numbness, tingling, and tightness of the chest that lasted for approximately 2 hours (Kwok, 1968).
The New England Journal of Medicine gave Kwok's letter the title, "Chinese-Restaurant Syndrome." Subsequently, readers responded, suggesting that the culprit was monosodium glutamate.
The following year, John W. Olney, M.D. reported that laboratory animals suffered brain lesions and neuroendocrine disorders after being exposed to monosodium glutamate (Olney, 1969). Scientists studying retinal degeneration in mice treated with free glutamic acid had noted that these mice became grotesquely obese. Olney, who speculated that the obesity might be a sign of damage to the hypothalamus (the area of the brain that regulates a number of endocrine functions, including weight control), found that infant laboratory animals given free glutamic acid suffered brain damage immediately, and assorted neuroendocrine disorders later in life. Pharmaceutical grade L-glutamic acid was often used to produce these disorders until neuroscientists observed that monosodium glutamate, an inexpensive food additive, could be substituted for laboratory-grade free glutamic acid in these studies and produce the same effects.
CONFIRMATION OF TOXICITY!
In the years that followed, neuroscientists replicated the work of Olney, and Olney spoke out repeatedly about the toxic potential of glutamic acid freed from protein prior to ingestion. In 1972, for example, Olney testified before the Senate Select Committee on Nutrition and Human Needs that ingestion of MSG places humans at risk, with the greatest risk being for the very young; and that a National Academy of Science panel organized to determine whether MSG ought to be banned from baby food had produced an "industry arranged whitewash" by a group of scientists with almost no experience in neuropathology (Gillette, 1972). In the early 1970s, manufacturers of baby food voluntarily removed the monosodium glutamate from their products, but replaced the monosodium glutamate with MSG-containing ingredients such as autolyzed yeast and hydrolyzed vegetable protein. In the late 1970s, manufacturers voluntarily removed all obvious MSG-containing ingredients from baby food.
Today scientists know that MSG kills brain cells and causes neuroendocrine disorders in laboratory animals; and that it causes adverse reactions in humans. Scientists know that the blood brain barrier, once thought to prevent glutamate that comes from exogenous sources (eating included) from entering the brain, is not fully developed until puberty; is easily damaged by such conditions as high fever, a blow to the head, and the normal course of aging; and, in the area of the circumventricular organs, is leaky at best at any stage of life. Scientists know that a diverse number of disease conditions such as ALS, Alzheimer's disease, seizures, and stroke are associated with the glutamate cascade (Blaylock, 1994).
Scientists also understand that MSG is simply processed free glutamic acid, or processed free glutamic acid combined with sodium (depending on how it is defined), and that glutamic acid is a neurotransmitter that causes nerves to fire; and when present in excess quantities, causes nerves to fire until they die. Scientists understand that in addition to the L-glutamic acid found in unprocessed, unfermented, unadulterated free glutamic acid, processed free glutamic acid invariably contains D-glutamic acid and brings with it pyroglutamic acid and other contaminants--some of which, depending on procedures used for processing and the protein source, are carcinogenic.
WHAT ARE THE ADVERSE REACTIONS OF MSG?
Ingestion of processed free glutamic acid (MSG) is known to produce a variety of adverse reactions in some people. These reactions, although seemingly dissimilar, are no more diverse than reactions found as side effects of certain neurological drugs. We do not know why some people experience reactions and others do not. We do not know whether MSG "causes" the condition underlying the reaction, or whether the underlying condition is simply aggravated by the ingestion of MSG. We only know that the reactions listed below are sometimes caused or exacerbated by MSG.
All forms of MSG (free glutamic acid that occurs in food as a consequence of manufacture) cause these reactions in MSG-sensitive people. That includes MSG found in a plant "growth enhancer" called AuxiGro, and MSG found in a variety of other fertilizers and fungicides that have been approved for spraying on growing crops, including crops identified as "organic."
The first evidence linking retinal degeneration to treatment with MSG was found by researchers testing the notion that glutamic acid might cure retinal degeneration. By 1969, evidence that treatment with MSG caused retinal degeneration had been confirmed many times.
WHO IS SENSITIVE TO MSG?
MSG-sensitive people report reactions ranging from simple skin rash to severe depression and life-threatening physical conditions. Two or more reactions occurring together, or one following another, are not uncommon. The amount of MSG ingested may play a role in the severity and specific nature of a reaction. The intensity or severity of a reaction also appears to be affected by alcohol ingestion and/or exercise just prior to, or immediately following, MSG ingestion, and some women report variations in their reactions at different times in their menstrual cycles.
DIAGNOSIS OF MSG SENSITIVITY!
Diagnosis of MSG sensitivity is extremely difficult.
Diagnostic tools generally available to physicians are limited to a procedure called "challenge." In a physician's office, an appropriate dose (or doses) of MSG would be given to the patient, and provision would have to be made for both restricting the patient's contact with other potential reaction triggers and observing reactions delayed by as much as 48 hours.
As an alternative, physician and patient working together may be able to identify, or rule out, MSG as a reaction trigger through analysis of a patient food diary. Restricting intake to totally unprocessed food and drink for three weeks, then reintroducing items, one at a time, may help identify offending sources of MSG.
OTHER FACTS ABOUT MSG
The MSG-reaction is a reaction to free glutamic acid that occurs in food as a consequence of manufacture. MSG-sensitive people do not react to protein (which contains bound glutamic acid) or any of the minute amounts of free glutamic acid that might be found in unadulterated, unfermented, food.
THESE ALWAYS CONTAIN MSG
Glutamate, Glutamic acid, Gelatin, Monosodium glutamate, Calcium caseinate, Textured protein, Monopotassium glutamate, Sodium caseinate, Yeast nutrient, Yeast extract, Yeast food, Autolyzed yeast, Hydrolyzed protein.
THESE OFTEN CONTAIN MSG OR CREATE MSG DURING PROCESSING
Carrageenan, Maltodextrin, Malt extract, Natural pork flavouring, Broth, Malt flavouring, Bouillon, Natural chicken flavouring, Soy protein isolate, Natural beef flavouring, Ultra-pasteurized, Soy sauce, Stock, Barley malt, Soy sauce extract, Whey protein concentrate, Pectin, Soy protein, Whey protein, Protease, Soy protein concentrate, Whey protein isolate, Protease enzymes, Anything protein fortified, Flavours and flavourings, Anything enzyme modified, Anything fermented, Natural flavour and flavourings, Enzymes anything, Seasonings
The new game is to label hydrolyzed proteins as pea protein, whey protein, corn protein, etc. If a pea, for example, were whole, it would be identified as a pea. Calling an ingredient pea protein indicates that the pea has been hydrolyzed, at least in part, and that processed free glutamic acid (MSG) is present.
Disodium guanylate and disodium inosinate are expensive food additives that work synergistically with inexpensive MSG. Their use suggests that the product has MSG in it. They would probably not be used as food additives if there were no MSG present.
MSG reactions have been reported to soaps, shampoos, hair conditioners, and cosmetics, where MSG is hidden in ingredients that include the words "hydrolyzed" and "amino acids."
Low fat milk products often include milk solids that contain MSG.Drinks, candy, and chewing gum are potential sources of hidden MSG and of aspartame. Aspartic acid, found in aspartame (NutraSweet), ordinarily causes MSG type reactions in MSG sensitive people. Aspartame is found in some medications, including children's medications. Check with your pharmacist.
Binders and fillers for medications, nutrients, and supplements, both prescription and non-prescription, enteral feeding materials, and some fluids administered intravenously in hospitals, may contain MSG.
According to the manufacturer, Varivax-Merck chicken pox vaccine (Varicella Virus Live), contains L-monosodium glutamate and hydrolyzed gelatin both of which contain processed free glutamic acid (MSG) which causes brain lesions in young laboratory animals, and causes endocrine disturbances like OBESITY and REPRODUCTIVE disorders later in life.