You may have heard someone claim they are “allergic” to monosodium glutamate, or perhaps you think you have an MSG allergy, or you’ve been wondering if claims about MSG side effects are true.
Here’s a review of just some of the research that has been undertaken to investigate whether an MSG allergy is something to be worried about or is even real.
The first report of a reaction to MSG, back in 1968, was an anecdotal account by one person after he ate at a Chinese restaurant – it was published as a letter to the editor in the New England Journal of Medicine.1 The writer described his reaction as generalized weakness, palpitations and numbness in the arms, but acknowledged that these symptoms may have been due to any number of ingredients in the meal including sodium, or alcohol from Chinese cooking wine, and not necessarily the MSG. However the letter spawned the idea that vague reactions such as these might be attributed to monosodium glutamate (MSG) and introduced the phrase Chinese Restaurant Syndrome.
In 1995, an independent scientific panel, the Federation of American Societies for Experimental Biology (FASEB) published a comprehensive analysis of the safety of MSG and included a list of MSG symptoms and alleged side effects that reports claimed were associated with consuming foods with MSG.2
According to FDA:
FASEB’s report concluded that MSG is safe. The FASEB report identified some short-term, transient, and generally mild symptoms, such as headache, numbness, flushing, tingling, palpitations, and drowsiness that may occur in some sensitive individuals who consume 3 grams or more of MSG without food. However, a typical serving of a food with added MSG contains less than 0.5 grams of MSG. Consuming more than 3 grams of MSG without food at one time is unlikely.3
The FDA, in its Q&A about monosodium glutamate, notes: “Over the years, FDA has received reports of symptoms such as headache and nausea after eating foods containing MSG. However, we were never able to confirm that the MSG caused the reported effects.”
Research on MSG, conducted for over decades, has found that most people who believe they respond adversely to MSG do not have these reactions when evaluated in carefully controlled tests. As Food Standards Australia New Zealand concludes in its thorough review affirming MSG’s safety, “Although the prevalence of CRS (Chinese Restaurant Syndrome) has been estimated to be about 1–2% of the general population it is not clear what proportion of the reactions, if any, can be attributed to MSG. The vast majority of reports of CRS are anecdotal, and are not linked to the actual glutamate content of the food consumed. Furthermore, when individuals with a suspected sensitivity to MSG are tested in double-blind challenges the majority do not react to MSG under the conditions of the study (or react equally to placebo). Many individuals may therefore incorrectly be ascribing various symptoms to MSG, when in fact some other food component may be the cause. This highlights the need for individuals with suspected MSG sensitivity to undergo appropriate clinical testing.”4
The Bottom Line: Seek a proper medical diagnosis if you believe you are reacting to something you’ve eaten.
Allergens are well defined and packaged foods list common allergens on their labels. Sensitivities are not uncommon and can be attributed to a wide variety of foods and ingredients. In Chinese food, for example, ingredients such as peanuts, sesame seeds, shell-fish or even egg can cause reactions for some people. This is why it’s important not to self-diagnose. As with any product to which you suspect you are having an allergic-type reaction consult a healthcare professional to get a proper medical diagnosis.
- Kwok RHM. Chinese-restaurant syndrome [letter]. N Engl J Med 1968; 278:796.
- Raiten DJ, Talbot JM, Fisher KD, eds. Analysis of adverse reactions to monosodium glutamate (MSG). J Nutr 1995; 125: 2892S–2906S
- FDA: “Questions and Answers on Monosodium Glutamate (MSG)“
- “Monosodium Glutamate, A Safety Assessment” (Technical Report Series No. 20), Food Standards Australia New Zealand (FSANZ)
Further references can be found on Wikipedia here.