Truth About MSG (Monosodium Glutamate)

Glutamate is an amino acid that exists naturally in all living things. It is found in protein as one of its building blocks and it can also be found in a "free form" not bound to other molecules. This "free form" of glutamate is the source of Umami taste and it exists naturally and in the highest quantity in delicious foods. This is the reason that foods such as meats, tomatoes, mushrooms, and cheeses taste so delicious. They all have a high content of "free" glutamate. sour bitter and salty.

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Monosodium glutamate (MSG) is the sodium salt of glutamic acid (glutamate). MSG is a flavor enhancer which has been used effectively for nearly a century to bring out the best flavor of foods. When MSG is added to foods, it provides a similar flavoring function as the glutamate that occurs naturally in food. MSG is comprised of water, sodium and glutamate. When eaten, MSG is separated by the body into a small amount of sodium and glutamate.

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Over 1,200 years ago, Oriental cooks discovered that some foods tasted better when prepared with a soup stock made from the seaweed, Laminaria Japonica. It was not until 1908 that Professor Kikunae Ikeda of the University of Tokyo isolated glutamate from the seaweed and unlocked the secret of its flavor-enhancing properties. Since then, MSG has been widely used as an effective means of making good food taste better.

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MSG is usually produced through fermentation - a process similar to that used in making beer, soy sauce, vinegar and yogurt. The process begins with the fermentation of corn, sugar beet or sugar cane or cassava. The finished product is a pure, white crystal which dissolves easily and blends well in many foods.

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Monosodium glutamate enhances the basic flavor of many foods. Studies have shown that MSG elicits a unique taste that is known as 'umami' in Japan, and often described as a savoury or meaty taste. Umami is the fifth basic taste . It can be defined as a unique taste both because it is distinct from the other basic tastes (sweet, sour, salty and bitter) and also from evidence of the existence of glutamate receptors within the tongue's taste cells, and cells within the brain which respond preferentially to the umami taste. This savoury taste is an integral part of cuisines around the world. It is found in the bouillons of Europe, the oyster sauce of China, and the soy and fish sauces of South-East Asia, the pizza and lasagne of Italy and the chowders and stews of America.

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MSG can be used in many savoury dishes including meat, fish, poultry and many vegetables, and in sauces, soups and marinades. While MSG harmonises well with salty and sour tastes, it contributes little or nothing to sweet or bitter foods.

MSG is a self-limiting substance - once the effective amount is used, adding more contributes little, if anything, to food flavor. Overuse of MSG, as with many other seasonings and spices, may cause some foods to have an undesirable taste.

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The glutamate added to foods for flavor represents only a small fraction of the total amount of glutamate consumed in the average daily diet. Results of taste panel studies indicate that a level of 0.1-0.8 % MSG by weight in food provides optimum enhancement of the food's natural flavor. This is within the range of glutamate that naturally occurs in foods.

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The average person consumes around 10 grams of bound glutamate and up to one gram of free glutamate daily. The human body creates about 50 grams of free glutamate daily. In contrast, the added intake of free glutamate through MSG amounts to approximately one-half gram per person, or 1/10 teaspoon daily.

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No. The glutamate naturally present in food and the glutamate derived from MSG are identical. It does not matter whether you select glutamate rich foods and ingredients like tomatoes, parmesan cheese, walnuts, soy sauce on the one hand or MSG on the other hand, the glutamate in each is the same.

Medical specialists have known for decades that your body does not distinguish between the glutamate found naturally in foods and that in MSG. In fact, even today's state-of-the-art technology can't separate them. For example, if you analysed a plate of spaghetti you could find out the total amount of glutamate in the dish. However, since glutamate is glutamate, there is no way to determine whether the glutamate came from tomatoes, Parmesan cheese or MSG.

They are digested and absorbed in the same way in the intestine. Once they are ingested, our bodies make no distinction between glutamate from foods such as tomatoes and glutamate from MSG. In fact, research has shown that glutamate from food or from MSG is important for the normal functioning of the digestive system.

Scientific authorities from around the world including the US Food and Drug Administration (FDA), the American Medical Association (AMA) and the The Federation of American Societies for Experimental Biology (FASEB) agree that the body handles glutamate in the same way regardless of its source.

As a result of consuming MSG or protein-based foods, a natural elevation of the blood glutamate level will occur. The level will return to 'baseline' (or the level before eating) in about three hours, no matter what the source of glutamate.

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MSG's low sodium content represents a minor contribution to the overall sodium level of a typical diet. By way of comparison, MSG contains about 12% sodium while table salt contains 39%. However, MSG is used at levels lower than salt. Considering all sources of dietary sodium (natural sodium content of foods, table salt, sodiumcontaining ingredients in processed foods, drinking water and pharmaceuticals), typical use of MSG contributes about one to two percent of the total sodium contained in the average diet.

Tastes have shown that when the salt level in food is reduced, food acceptability decreases. However, by using a small amount of MSG in conjunction with a decreased level of salt an acceptable flavor profile can be maintained, while sodium content can be reduced by as much as 30-40%.

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Yes. Research in Europe, the United States and Asia clearly shows that MSG used in prepared foods or as a condiment is safe for humans of all ages.

MSG has been safely used as a food ingredient since the early 1900's. It is one of the most thoroughly tested of all food ingredients, with hundreds of scientific studies confirming its safe and effective use. MSG's safety has been repeatedly affirmed by regulators and scientific agencies around the world.

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In the United States, MSG has been included in the FDA's list of substances known as Generally Recognised as Safe (GRAS) since 1959. Foods designated as GRAS include ingredients like sugar, baking powder and vinegar whose safety has been established through common use in food and/or through extensive testing.

Since FDA's classification of MSG as GRAS in 1959, new and existing research on MSG has undergone continuous evaluation. In the most recent review, completed in 1995, the Federation of American Societies for Experimental Biology (FASEB) reaffirmed the safety of MSG for the general population. In its review, commissioned by the FDA, FASEB found no evidence linking MSG to any serious or long-term health effects, which led the FDA to again reaffirm that MSG is a safe food ingredient at normally consumed levels.

In 1987, the United Nations World Health Organization/Food and Agriculture Organization's Joint Expert Committee on Food Additives (JECFA) reviewed the scientific literature on glutamate citing 230 scientific studies. It concluded that, on the basis of available data (chemical, biochemical, toxicological and other) the total dietary intake of glutamates arising from their use at the levels necessary to achieve the desired technological effect and from their acceptable background in food, do not, in the opinion of the Committee represent a hazard to health. It found the evidence of safety of glutamate so convincing that it allocated an Acceptable Daily Intake (ADI) for glutamate of 'not specified'. 'ADI not specified' indicates that because the total daily intake of glutamate does not represent a health hazard, it is not deemed necessary to put a numerical limit on its use. This means that glutamate is placed in the safest category of food ingredients.

In 1991, the European Commission's Scientific Committee for Food (SCF) also affirmed MSG's safety. Having reviewed the most advanced and up-to-date research on glutamate, the SCF published a report in 1991 which designated an 'ADI not specified' for glutamate.

In 1992, the Council on Scientific Affairs of the American Medical Association (AMA) issued a resolution supporting MSG's safety. In particular, the Council stated that "The scientific record does not support the conclusion that MSG or Lglutamic acid as either exogenously-added flavor enhancing substances or naturally occurring components of food proteins pose a significant public health risk."

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Yes. Extensive research shows that MSG is safe for all humans, including infants and pregnant women. Scientific studies show that infants metabolise MSG in just the same way as adults.

Breast milk is naturally high in glutamate; the average human infant ingests 150-200 milligrams of free glutamate daily from its mother's milk. Nursing mothers should also know that the level of glutamate in their breast milk does not increase following ingestion of glutamate.

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No. There are many known 'triggers' for headaches, including diet and stress. A wide range of foods have been implicated as headache triggers. However, a 1990 critical review of the literature on food-triggered headaches (Food triggered migraine: a critical review. Annuls of Behavioural Medicine, 12:51-651, 1990) concluded that the relationship is controversial. The review states that there is no evidence to support an association between MSG and migraine headaches.

Reports that MSG is a vasoactive substance - meaning it constricts or dilates blood vessels, thereby producing migraine headache - have never been confirmed in a scientifically controlled study. There are many theories about what causes migraine headaches including heredity, neurological brain disorders and blood vessel disorders.

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Anecdotal reports of adverse reactions to various foods or food ingredients are not uncommon. In fact, there are reported reactions in the scientific literature to almost every known food ingredient. For decades, anecdotal reports have suggested that a small percentage of the population may be sensitive to MSG. However, these reactions have been observed to be mild and transitory.

In 1968, Robert Ho Man Kwok, M.D..described a collection of symptoms he allegedly experienced after eating Chinese food. He coined the phrase "Chinese Restaurant Syndrome" (CRS) to describe these symptoms, which included numbness at the back of the neck and a feeling of pressure in the face and upper chest muscles.

As a consequence of Kwok's account, Kerr and colleagues developed a subjective questionnaire to assess the prevalence of CRS in the population. The survey employed listed 18 adverse symptoms related to food. Only 1.8% were reported as possible CRS symptoms.

Added to this, data from the Centers for Disease Control in the US showed that reported reactions to MSG accounted for less than 1% of food related complaints between 1975 and 1987.

In 1993, Tarasoff and Kelly published a study examining the sensory side effects possibly caused by ingesting MSG. Using a randomized double blind crossover study, 71 healthy participants were administered five (5) different treatments, which included two (2) placebos and three (3) different doses of MSG in random order. Neither the researchers nor the subjects knew which or how much of the test materials was being consumed. Two hours after ingestion, each subject was interviewed and half reported they experienced more than one symptom regardless of MSG content. While the common reaction was none at all, the next significant symptom reported was tingling and thirst, which was experienced by the subgroup of strong reactors. Thus similar to Dr. Kerr, Tarasoff and Kelly found that the small number of effects seen were statistically insignificant and that MSG in food had no discernible effect for healthy individuals.

The latest (2000) multicenter double-blind placebocontrolled study in 130 subjects (the largest to date ) on CRS conducted by Geha and colleagues from Harvard University, Boston University of Public Health, Northwestern University and University of California concluded that "Neither persistent not serious effects from MSG were observed, and the responses were not consistent on retesting."

If a person believes he/she may react to a particular food or ingredient, he/she should seek a medical diagnosis from a board-certified allergist and not rely on self-diagnosis. A placebo-controlled, doubleblind food challenge is the most accurate and reliable method to properly evaluate complaints of food sensitivity.

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'Chinese restaurant syndrome' describes transient discomfort some people may feel after ingesting certain foods and beverages. In 1987, JECFA concluded that "Properly conducted double-blind studies among individuals who claimed to suffer the syndrome did not confirm monosodium glutamate as the causal agent". (Joint FAO/WHO Expert Committee on Food Additives. L-glutamic acid and its ammonium, calcium monosodium and potassium salts. In Toxicological Evaluation of Certain Food Additives and Contaminants. WHO Food Additives Series No. 22, New York: Cambridge University Press, pp. 97-161, 1988.) This conclusion was affirmed by a comprehensive review and strictly controlled study at the University of Western Sydney in 1993. (Tarasoff L, Kelly M. F. Monosodium L-glutamate: a double blind study and review. Food Chemical Toxicology, 31: 1019 - 1035, 1993.

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