Food Additives - MSG: Monosodium Glutamate

Another free booklet is the FDA's Monosodium Glutamate (MSG) page.
 

"...people were no more likely to respond to MSG than to a placebo..."

The American Dietetic Association denies a conclusive link between MSG and headaches. According to an American Dietetic Association Nutrition Fact Sheet supported by a grant from Ajinomoto, "Some people have reported mild, short-term symptoms after consuming MSG, but under clinical testing, people were no more likely to respond to MSG than to a placebo."

According to the Glutamate Association, although anecdotal reports of adverse reactions to MSG exist, there are reported reactions in the scientific literature to almost every known food ingredient.  Many people who claim to have a sensitivity to MSG actually do not.  The only way to accurately determine a true food sensitivity is to perform an individualized placebo-controlled, double-blind food challenge.
 

"...the body does not distinguish between glutamate from foods like tomatoes or MSG..."

Glutamate occurs naturally in tomatoes, mushrooms, and walnuts - to name a few.  The International Food Information Council Foundation states that "the body does not distinguish between glutamate from foods like tomatoes or MSG added to tomato sauce."  The IFIC also states that the average American consumes roughly 0.55 grams of MSG spread out through an entire day.  In oriental populations like Taiwan, figures are much higher, averaging 3 grams per day.

Evaluation of risks posed by MSG: In 1959, the FDA classified MSG as "Generally Recognized as Safe" (GRAS) due to its history of safe use. In 1968, a physician asked the readers of The New England Journal of Medicine to give him some feedback on the symptoms of discomfort after eating food in Chinese restaurants. The response was overwhelming. Thus, the phrase "Chinese Restaurant Syndrome" (CRS) was coined, and the controversy was here to stay.

The FDA has been evaluating the safety of MSG as part of an ongoing project initiated in 1970. This was to review safety data on the ingredients of processed foods such as hydrolyzed proteins, which contain 5 to 20 percent of glutamates and other glutamate compounds. Until its evaluation is completed, MSG and related compounds remain on the GRAS list.

In 1980, a review by the Federation of American Societies for Experimental Biology (FASEB) concluded that MSG was safe at the current level of use, but recommended additional study to determine MSG safety at significantly increased levels of consumption. In 1986, the FDA's Hypersensitivity Committee concluded that MSG posed no threat to the general public. However, brief reactions of discomfort might occur in some people. The 1987 Joint Expert Committee on Food Additives of the United Nations Food and Agriculture Organization (FAO) and the World Health Organization (WHO) placed MSG in the safest catagory of food ingredients. In 1989, the FDA's Clinical Nutrition Assessment Section reported that they could find no evidence that MSG is a health hazard to large segments of the general population. The report added that although there is some evidence that dose-dependent mild reactions occur in a small portion of the population, the public at large was safe. It recommended continued label declaration, ongoing evaluation, and surveillance of adverse MSG reactions, to protect public health. The FDA Health Hazards Evaluation Board in 1990 concluded that dietary intake of glutamate did not present a hazard to human health and did not require any additional regulatory action.

In 1991, the report by the European Community (EC) Scientific Committee for Foods reaffirmed MSG safety," and classified its "acceptable daily intake" as "not specified, the most favorable designation for a food ingredient. Furthermore, the EC committee went on to say that "infants, including prematures, have been shown to metabolize glutamate as efficiently as adults and do not display any special susceptibiltiy to elevated oral intakes of glutamate." A similar finding was published in a study in 1991 by the Joint FAO/WHO Expert Committee on Food Additives and Coloring. Also in 1991, the International Glutamate Technical Committee (IGTC), an industrial association, released a report summarizing the available published literature concerning the safety of dietary glutamate. The report concluded that even when 100 to 150 mg of glutamate per kg of body weight (7 to 10 g total) was ingested with food at one time, it resulted in a very minimal elevation in plasma glutamate concentration. The evidence indicated that as much as 35% of orally ingested glutamate is metabolized before reaching the systemic circulation. Brain cells and human placenta are shielded from any glutamate present in the blood. Breast milk is also not affected by plasma glutamate concentration. The IGTC concluded that MSG is probably not "the culprit" in CRS. Consistent with this conclusion, the Institute of Food Technologists Expert Panel on Food Safety and Nutrition declared "MSG is a safe, efficacious flavor enhancer for the vast majority of the population."

In contrast, the National Organization Mobilized to Stop Glutamate (NOMSG) published a report in 1990, based upon weak and heavily flawed findings, heavily criticizing the widespread use of MSG. The Council on Scientific Affairs (CSA) rejected NOMSG's report for insufficient evidence.

The Applied Nutrition's Adverse Reaction Monitoring Systems (ARMS) reported in 1990 that a small percentage of individuals have moderate reactions such as skin flushing, tightening of the jaws and upper chest muscles, and headaches shortly after ingesting MSG. Aggravation of asthma after several hours of consuming MSG have been reported. Other studies have reported brief burning sensations in the back, neck, forearms and chest, nausea, rapid heart beat, drowsiness, and weakness.

The problem with the reports on adverse MSG reactions that the FDA received is that they were not controlled studies, but anecdotes. However, many of these safety assessments were prompted by unconfirmed reports of MSG-related illnesses. Between 1980 and 1994, the symptom most frequently reported to the FDA Monitoring System was headache, and no other severe reactions were documented.

In 1992, the FDA contracted FASEB to review the available scientific data. In July 1995, the FASEB report to the FDA offered a new safety assessment evaluation based on existing studies. The report reaffirmed the adverse reactions that were discussed earlier and confirmed that no evidence exists to suggest that MSG contributes to Alzheimer's Disease, Huntington's Disease, amyotrophic lateral sclerosis, AIDS dementia complex, or any other long-term or chronic disease, all claimed by NOMSG. The American Medical Association's Council on Scientific Affairs, the National Academy of Sciences, as well as the FDA, have all determined that MSG, at current consumption levels, is safe.

Has the testing been adequate? After 26 years of research, the answer is probably yes. But now that FASEB has reported its findings to the FDA, perhaps the the FDA should consult the experts and assess the need for further controlled research, focusing only on adverse effects.

FAQs

MSG is a safe ingredient when its sole purpose is that of improving the flavor of food. However, many questions have recently arisen about the general safety of its use and its possible link to health problems. The following are answers to some of these general questions:

1. Does MSG cause Chinese Restaurant Syndrome (CRS)? Some people report symptoms such as dizziness, flushing, nausea and a feeling of tightness or pressure in the upper part of the body after eating Chinese food, which often contains MSG. The results of many research studies find no positive correlation between CRS and MSG. These feelings have been known to occur after the consumption of beverages such as spicy tomato juice, orange juice, coffee, and tea.

    

2. Does MSG cause brain damage in humans? Numerous experiments done on animals (dogs, monkeys, rodents) found no evidence that MSG in the diet causes brain damage.

    

3. Does MSG affect the fetus of pregnant women? MSG does not pass through the placental barrier, reaching the unborn baby.

    

4. At what levels should MSG be used? In processed food, MSG is added at 0.1 percent to 0.8 percent of food. For home use, about one-half teaspoon per pound of meat or per four to six portions of vegetables can be used.

    

5. What does MSG taste like? There is no word to describe exactly how MSG tastes, but it can be said that the taste of glutamate is to tomato, cheese, and meat, what sweetness is to sugar, sourness is to lemon, and bitterness is to coffee.

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This page was updated on May 19, 2006