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Volume 38, No. 2

Free Glutamic Acid (MSG): Sources And Dangers

Why is free glutamic acid added in vast amounts to processed foods? Our large profit-driven food companies have found that manufactured free glutamic acid, in the form of monosodium glutamate (MSG), hydrolyzed vegetable proteins, etc., etc., when added to our processed foods, masks off flavors and makes the blandest and cheapest foods taste wonderful.

The story is fascinating. For thousands of years kombu and other seaweeds have been added to foods in Japan to enhance flavor. In 1908 a Japanese scientist discovered that the active ingredient in kombu is glutamic acid and then the use of its sodium salt, monosodium glutamate, began in Japan. During the Second World War American quartermasters realized that Japanese army rations tasted great. Following the war, they introduced monosodium glutamate, the flavor enhancing ingredient in the Japanese rations, to the food industry; and the world-wide use of processed free glutamic acid began to explode.

An excellent NOHA lecture on the dangers and hidden sources of processed free glutamic acid was given at Evanston’s Whole Foods Market on February 14, 2000, by NOHA Board Member Jack Samuels. He is president of the Truth in Labeling Campaign.

Glutamic acid is a neurotransmitter that excites our neurons (not just in our tongues). This electrical charging of neurons is what makes foods with added free glutamic acid taste so good. Unfortunately, the free glutamic acid can cause problems in many people. Actually, our brains have many receptors for glutamic acid and some areas, such as the hypothalamus,1 do not have an impermeable blood-brain barrier, so free glutamic acid from food sources can get into the brain, injuring and sometimes killing neurons. At least 25 per cent of the U.S. population react to free glutamic acid from food sources. Today, we recognize that those reactions range from mild and transitory to debilitating and life threatening. Please see Table 1.

Glutamic acid is widely distributed in proteins. When we eat it bound as part of whole, unprocessed proteins, it helps nourish us as it has for millennia. Glutamic acid bound as part of whole, unprocessed protein does not cause problems in people who react to the free glutamic acid in manufactured food, where it is hidden in ingredients with about 40 different names. Please see Table 2.

Monosodium glutamate and other forms of free glutamic acid can be manufactured cheaply and sometimes it is even just a byproduct of other food processes. For example, the brewer’s yeast from the brewing industry contains free glutamic acid. Since free glutamic acid is cheap and since its neurotoxic nerve stimulation enhances so wonderfully the flavor of basically bland and tasteless foods, such as many low-fat and vegetarian foods, manufacturers are eager to go on using it and do not want the public to realize any of the problems. In 1999 in an article in a peer-reviewed journal, NOHA Board Member Adrienne Samuels, PhD, wrote a history of the many deceptions used by those manufacturers, "The Toxicity/Safety of Processed Free Glutamic Acid (MSG): A Study in Suppression of Information."2 She points out "how easily truth can be hidden and how seemingly isolated incidents actually can be badly flawed research, direct suppression of information, and dissemination of biased information orchestrated by one group or industry."

According to Dr. Samuels, the evidence of toxicity is overwhelming. Exposed laboratory animals suffer brain lesions and neuroendocrine disorders. Scientists studying retinal degeneration in mice treated with free glutamic acid have noted that these mice also became grotesquely obese following administration of free glutamic acid. The vulnerable hypothalamus in our brains regulates weight control, as well as other endocrine functions. When the brain is deluged with more free glutamic acid than it can handle, scientists know that problems and diseases can develop. For example, they know that a diverse number of disease conditions such as ALS (amyotrophic lateral sclerosis, a progressive degeneration of neurons and motor cells of the brain), Alzheimer’s disease, seizures, and stroke are associated with the glutamate cascade.

Faced with growing evidence of toxicity from processed free glutamic acid, its manufacturers and users formed The Glutamate Association. Dr. Samuels states:


The parent organization of The Glutamate Association funded scientists to do research and to make public statements about the "safety" of MSG. Dr. Samuels describes their research and many of their actions in fascinating detail. A few of their ploys are as follows:

  • Although it had been established that brain lesions could not be identified if examination was not done within 24 hours after insult, glutamate-industry researchers routinely examined the brains of test animals after 24 hours had elapsed.
  • Monkeys are much less sensitive to glutamate than humans. Mice and rats have reactions closer to ours. According to Dr. John Olney, "The same oral dose of glutamate that causes a dramatic increase in blood glutamate concentrations in humans, causes no increase at all in monkeys. Therefore, it is difficult to understand why so much money and effort was expended on oral glutamate monkey studies, unless the goal was to amass an unchangeable mountain of negative evidence that could serve as basis for fostering the misleading impression, and fueling the spurious argument that if monkeys are resistant to glutamate-induced brain damage, other primates, including humans, must be similarly resistant."
  • In studies with people, glutamate industry researchers have sometimes used aspartame (Nutrasweet®) as the "placebo" for their "control" groups. Aspartame contains aspartic acid, which is a structural analog of glutamic acid and causes the same toxic effects. Thus, they could be confident that they would get the same effects in the experimental and in the "control" groups.
  • In statistics we need to be acutely alert to the manner in which the population for study is chosen. For instance, scientists can say they are doing a random study, but, we must ask, "From what group are the people drawn?" One approach used by glutamate industry researchers was to pretest the group with placebos containing, for example, aspartame, carageenan, or enzymes to which MSG-sensitive people would react. In this way, by choosing for their population people, who do not react to the so-called "placebos," the scientists could be pretty sure that their subjects would not react to MSG.
  • Another way to reduce reactions is to put the MSG in capsules. Then, it will be slowly released and reactions of MSG-sensitive people will be blunted—compared to their reactions to the same amount of MSG sprinkled on food.
  • Give MSG with sucrose. This will also blunt reactions. Dr. Blaylock has explained that a tremendous amount of energy is required for the brain to manage glutamic acid and, of course, glucose is what our brains use for energy.
  • To defend themselves against epidemiological studies indicating that 25-30 per cent of the population reacted to monosodium glutamate and against individual reports of human adverse reactions that included migraine headache, seizures, asthma, and depression, the glutamate industry built the fiction that a few people might react to monosodium glutamate with the "Chinese restaurant syndrome": "burning," "tightness," and "numbness," all occurring at the same time, within two hours following ingestion. They sent out a questionnaire and got 3,222 respondents, of whom 1.8 per cent reported having the exactly defined "Chinese restaurant syndrome." The fact that an additional 41.2 per cent of the subjects reported experiencing conditions that are associated with MSG-induced adverse reactions such as headache, diarrhea, chest pain, dizziness, palpitation, weakness, nausea/vomiting, abdominal cramps, chills, heartburn, unusual thirst, unusual perspiration, flushing sensation in face or chest, and tingling was ignored. Migraine headache, seizures, tachycardia, hives, skin rash, and depression, which were not offered as options, were not considered. Soon the FDA (U.S. Food and Drug Administration) began to disseminate the misinformation that approximately 2 per cent of the population might be sensitive to MSG, reacting with the mild and transitory reactions of "Chinese restaurant syndrome."

Dr. Samuels spells out much evidence of cooperation between governmental departments, especially the FDA, and the glutamate industry. Scientists at many prestigious universities have done glutamate-industry funded research and peer-reviewed journals have published flawed research on the "safety" of MSG. Glutamate industry representatives and friends sit on boards of "independent" organizations. Glutamate industry researcher and spokesman Ronald Simon, MD, has been a member of the Scientific Advisory Board of the Center for Science in the Public Interest (CSPI). Monsanto’s Robert Shapiro sits on the board of the Tufts University School of Nutrition.

On January 14, 1998 AuxiGro®, which contains processed free glutamic acid, was registered as a growth enhancer with the EPA (U.S. Environmental Protection Agency) and permission was granted to spray it on all agricultural products. AuxiGro® gives plants sprayed with it the false signal that they are under "stress." The plants respond by pulling additional nutrients from the soil and thus grow much larger, increasing yields. The recent huge potatoes and yams in the supermarket would appear to be a direct result of AuxiGro®.

Dr. Samuels has presented us with many facts. She concludes: "The key to having the system work for those who use it to deceive others is the fact that few, if any, will take the time to review the facts with detachment and without prejudice and that whistle blowers are punished."

Some people are sensitive to minute amounts of free glutamic acid. For others, a larger dose or more than one dose is required to elicit reactions, which can be either immediate or delayed. In all cases, babies and small children are most vulnerable. Reacting to pressure stemming from the research on neurotoxicity and on injury to the developing infant’s endocrine system, baby food manufacturers voluntarily removed monosodium glutamate from their products in the early 1970s but they often left actual free glutamic acid in their products, as "autolyzed yeast and hydrolyzed vegetable protein."

Today, free glutamic acid is ubiquitous in processed food. What should we do?

  • For ourselves individually, we need to consume truly natural, unfermented, unadulterated, unprocessed protein.
  • For everyone everywhere, we need to communicate to our friends and relatives, our local newspapers, over the Internet, and to our congresspersons and senators—the facts about the deceptive research and the misleading food labeling.

When the word spreads and the public demands food without neurotoxic free glutamic acid, then our lives can be dramatically improved and we can be free from this often hidden source of suffering.

For more information, contact Jack and Adrienne Samuels at the Truth in Labeling Campaign, P. O. Box 2532, Darien, IL 60561;; or


Table 1




Extreme rise or drop in blood pressure

Rapid heartbeat (tachycardia)



Swelling Muscular

Flu-like achiness

Joint pain




Dizziness, Light-headedness, Loss of balance

Disorientation, Mental confusion

Anxiety, Panic attacks

Hyperactivity, Behavioral problems in children

Lethargy, Sleepiness, Insomnia

Migraine headache

Numbness or paralysis



Slurred speech




Stomach cramps

Irritable bowel



Asthma, Shortness of breath

Chest pain, Tightness

Runny nose, Sneezing


Hives or rash

Mouth lesions

Temporary tightness or partial paralysis (numbness or tingling) of the skin Flushing Extreme dryness of the mouth


Swelling of prostate Nocturia

Visual Blurred vision Difficulty focusing

Table 2

Using the term "MSG" to stand for processed free glutamic acid, which causes the reactions in sensitive people, Mr. Jack Samuels gave us at his NOHA lecture the following listing for hidden sources:

These ALWAYS contain MSG:

Glutamate, Monosodium glutamate, Monopotassium glutamate, Glutamic acid, Calcium caseinate, Gelatin, Textured protein, Hydrolyzed protein (any protein that is hydrolyzed), Yeast extract, Yeast food, Autolyzed yeast, Yeast nutrient

These OFTEN contain MSG or create MSG during processing:

Flavor(s) & Flavoring(s), Natural flavor(s) & flavoring(s), Natural pork flavoring, Bouillon, Natural beef flavoring, Stock, Natural chicken flavoring, Broth, Malt flavoring, Barley malt, Malt extract, Seasonings (the word "seasonings"), Carrageenan, Soy sauce, Soy sauce extract, Soy protein, Soy protein concentrate, Soy protein isolate, Pectin, Maltodextrin, Whey protein, Whey protein isolate, Whey protein concentrate, anything Protein fortified, Protease, Protease enzymes, anything Enzyme modified, Enzymes, anything Ultra-pasteurized, anything Fermented

Jack Samuels also warned us about low fat milk products with milk solids that contain MSG and about soaps, shampoos, and cosmetics. We also need to watch the binders and fillers in medications, nutrients, and supplements. "Reactions to MSG are dose related, i.e., some people react to even very small amounts." MSG-induced reactions can be delayed as much as 48 hours or can occur immediately after ingestion or exposure.

1Blaylock, Russel L., MD, Excitoxins: The Taste that Kills, Health Press, Santa Fe, NM, 1994, page 19. Dr. Blaylock spoke for NOHA in November 1995 on "Food Additives and Brain Damage." 2Accountability in Research, 6:259-310, 1999.

Article from NOHA* NEWS, Spring 2000

*The American Nutrition Association was formerly known as the Nutrition for Optimal Health Association [NOHA].

For informational purposes only - not intended as medical advice, diagnosis or treatment, nor an endorsement by the American Nutrition Association®. Use permitted for non-profit and non-commercial uses or by healthcare professionals in their practice, with attribution to Other use only with written ANA℠ permission. Views expressed are those of the author and not necessarily those of the ANA℠. Works by a listed author subject to copyrights as marked. © 2010 ANA℠