Monosodium Glutamate (MSG): What It Is, How It Tastes and What Regulators Say

The glutamate in a shaker of MSG is chemically the same as the free glutamate in tomatoes and cheese. MSG, monosodium glutamate, just delivers it as a sodium salt, and it adds the savory taste called umami. It isn’t a spice or herb but a manufactured seasoning, made today by fermenting starch, sugar beets, sugar cane or molasses. A Japanese chemist pinned that savory taste on glutamate in 1908, and FDA classes MSG as generally recognized as safe,¹ while Europe’s food safety authority sets a daily ceiling for it and the other glutamate additives.²

At a glance

What it is

Glutamate is everywhere in food. It occurs naturally in our bodies and in many foods, FDA notes, and the free glutamate in foods like tomatoes and cheeses is chemically the same as the glutamate in MSG.¹ MSG just delivers that same glutamate as a sodium salt.

How it tastes

Umami is one of the five basic tastes, a savory or meaty taste produced by three natural substances: glutamate, guanylate and inosinate. Foods with natural umami include mushrooms, tomatoes, seaweed and cheese.

On its own, a few crystals of MSG taste faintly salty and brothy, not strong. In a dish it comes across as fullness and depth, like a long-simmered stock, more than as a flavor you can name.

History

• Discovery. In 1908 Ikeda Kikunae, a Japanese chemist, identified glutamate as the source of the savory taste of a traditional seaweed broth. Ajinomoto, which sells the seasoning he developed, says he named the taste umami.³
• First product. Ajinomoto says sales of its seasoning AJI-NO-MOTO began in 1909, and calls it the world’s first umami seasoning. Ikeda’s discovery led to commercial production of MSG from seaweed; today it’s made by bacterial fermentation.
• “Chinese restaurant syndrome.” Reports of reactions to MSG first appeared in 1968. The informal name came from the belief that some restaurant cooks used it extravagantly. Later research found no conclusive link between the reported symptoms and normal levels of MSG.⁴

A few other stories about how MSG spread get repeated a lot: that it was first marketed to Japanese housewives, that Campbell’s was its first American customer, and that it reached the United States through packaged foods before restaurants. We couldn’t trace them to a source we could open, so we’ve left them out.

How it is used

MSG is an important ingredient in the cuisines of China and Japan. You use it much like salt: a pinch in soups and broths, stir-fry sauces, marinades, dressings, fried rice, vegetables and egg dishes. It’s also a common ingredient in seasoning blends and snack seasonings. A typical serving of a food with added MSG contains less than 0.5 grams, FDA notes.¹

Since MSG adds savoriness without much saltiness, some cooks use it to cut back on salt. We found no regulator figure for how much sodium that saves; see MSG vs. salt for the comparison. For technique, see cooking with MSG.

Labels

FDA requires foods with added MSG to list it by name in the ingredients; it can’t hide under “spices and flavoring.” Ingredients like hydrolyzed vegetable protein naturally contain free glutamate, and FDA says products containing them can’t claim “No MSG” or “No added MSG” on the package.¹ Some popular seasoning blends have MSG as a main ingredient; see sazón seasoning for one example.

Safety

United States. FDA considers adding MSG to food generally recognized as safe. It cites a 1990s report by the Federation of American Societies for Experimental Biology (FASEB) that concluded MSG is safe. The report also noted that some sensitive people who eat 3 grams or more of MSG without food may have short-term, generally mild symptoms such as headache, numbness, flushing, palpitations and drowsiness. FDA adds that eating more than 3 grams without food at one time is unlikely, and that it was never able to confirm that MSG caused the effects people reported to it.¹

European Union. In 2017 EFSA set a group acceptable daily intake of 30 mg per kg of body weight per day for glutamic acid and its salts, E 620 to E 625. For a 70 kg (154 lb) adult, that’s 2.1 grams a day by our math. EFSA found that exposure may exceed the ADI for people in every age group whose diet is high in foods with these additives. For some highly exposed young people, it may exceed doses linked to effects such as headache. EFSA recommended reviewing the maximum levels allowed in foods.²

The two agencies are answering different questions. FDA’s GRAS status says MSG is safe as normally used; EFSA’s ADI sets a daily ceiling for all added glutamates together.

Health benefits. We found no regulator or systematic review describing a health benefit of MSG, and we’re not claiming one.

Substitutes and comparisons

For glutamate-rich alternatives, see MSG substitutes. Naturally umami foods include mushrooms, tomatoes, seaweed and cheese. Related: MSG vs. salt, cooking with MSG, soy sauce powder and mushroom spices.