Monosodium Glutamate (MSG): Is It Bad For You?

MSG is a sodium salt of glutamic acid, a common amino acid. MSG occurs naturally in glutamate-rich foods, like tomatoes, mushrooms, aged cheeses, seaweed, anchovies and walnuts, says Harbstreet. It’s also found in meat, seafood, and soy and fish sauces. Glutamate is also one of the most “abundant” amino acids in human breast milk, according to a 2020 report in Frontiers in Immunology^[1]van Sadelhoff JHJ, Wiertsema SP, Garssen J, Hogenkamp A. Free Amino Acids in Human Milk: A Potential Role for Glutamine and Glutamate in the Protection Against Neonatal Allergies and Infections. Frontiers in Immunology. 2020;11:1007. .

MSG is known for its savory umami flavor, one of five basic tastes along with sweet, sour, bitter and salty, and it’s frequently added to chips, frozen vegetables, processed meat, bullion, seasoning, condiments and other packaged foods.

The amino acid also contains about one-third of the sodium in table salt, making it a helpful tool to reduce sodium without sacrificing flavor, according to Harbstreet. It’s also known to enhance any accompanying flavors in the food in which it’s prepared.

As an additive, MSG is made by fermenting starch, sugar beets, sugar cane or molasses, similar to the way wine or yogurt is fermented.

The Food and Drug Administration (FDA) classifies MSG as “generally recognized as safe” (GRAS) and doesn’t require MSG to be labeled or included in the ingredients if it’s naturally occurring. However, if it’s added to a food, it must be listed as an ingredient.

Typically, ingredients including hydrolyzed vegetable protein, protein isolate, textured vegetable protein, yeast extract or “natural flavors” indicate a food may contain MSG, says Harbstreet.

When it comes to the safety of consuming MSG, research shows you and your wife both have ground to stand on.

Most people don’t have any negative response to MSG at average consumption levels, though some people may be sensitive to it.

In the 1990s, the Food and Drug Administration commissioned a group of independent scientists to investigate whether MSG was making people sick. They concluded it’s safe but reported that individuals who consume 3 grams or more of MSG without food and are sensitive to the amino acid could have temporary symptoms of discomfort, such as headache, numbness, flushing, tingling, palpitations and drowsiness^[2]Food and Drug Administration, HHS. Food Labeling; Declaration of Free Glutamate in Food. Federal Register Online. 1996; 61(178):48102-48110. .

However, ingesting that much MSG without food would be difficult. In fact, you’d have to put it in a liquid and drink it, as some research participants were asked to do. A 2023 review of available literature estimates the average intake of food with added MSG in the U.S., Europe and the UK is 0.6 grams per day. The averages are higher in East Asia, topping out at 1.6 to 2.3 grams per day in Japan and South Korea, respectively^[3]Ahdoot E, Cohen F. Unraveling the MSG-Headache Controversy: an Updated Literature Review. Curr Pain Headache Rep. 2023. .

The European Food Safety Authority recommends a daily intake of less than 30 milligrams per day per kilogram of body weight^[4]Mortensen A, Aguilar F, Crebelli R, et al. Scientific Opinion on the re-evaluation of glutamic acid (E 620), sodium glutamate (E 621), potassium glutamate (E 622), calcium glutamate (E 623), ammonium glutamate (E 624) and magnesium glutamate (E 625) as food additives. EFSA Journal. 2017;15(7):4910. .

According to Food Allergy Research and Education (FARE), the body metabolizes the simple compound in added MSG the same way it metabolizes naturally occurring MSG, noting it’s important to understand the difference between a food allergy and an intolerance. Allergies involve the immune system while an intolerance is a disruption of the digestive tract. FARE has no reported cases of immune-related allergies to MSG, but that doesn’t mean it’s not making some people queasy. If it makes you feel ill, avoiding it makes sense.

Studies haven’t been able to reliably replicate the negative symptoms in human studies with people consuming typical amounts of MSG, but individuals who are experiencing an intolerance can work with a registered dietitian or health care provider to determine if MSG is the cause and, if so, reduce the amount in their diets.

The relevant question here is: Does eating chips with MSG make you feel sick?

If so, you may either have an intolerance to MSG or be responding to any number of other chemicals, additives or natural ingredients in chips, such as gluten or lactose.

Food should taste good. It should also make you feel good and provide nutrients, energy and satisfaction.

If your favorite chips are deep-fried and full of ingredients you don’t recognize, you might want to reconsider how much or how often to eat them, but, if MSG doesn’t make you feel bad, it may not be the most pressing reason to cut back.

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