The food additive known as MSG has long been associated with “Chinese Restaurant Syndrome,” a blanket term that describes negative reactions people claim to experience after eating American-Asian take-out, symptoms ranging from headaches, burning sensations, and nausea to chest pain, numbness, and drowsiness.
As a result, signs such as the one pictured at the top of this post can be seen in the windows of most Asian restaurants, and similar labels can be found on many Asia food products in the grocery store.
What is MSG, and does it deserve to be so maligned?
A Little Background
For millenia, the Japanese have been using kombu, a type of seaweed, to flavor soups. In 1908, Japanese chemist Kikunae Ikeda found that the crystals that form on the surface of dried kombu leaves are a rich source of monosodium glutamate, or MSG. He also identified the unique, savory taste sensation that MSG provides and called it umami, which loosely translates to “delicious” in Japanese (and we have taste receptors on our tongues specifically adapted to perceiving this taste).
The amino acid glutamate, found in many high-protein foods, is responsible for the umami taste sensation. Foods rich in glutamates include parmesan, mushrooms, ripe tomatoes, dry-aged beef, and ocean fish.
The Japanese company Ajinomoto began selling MSG as a seasoning in 1909, extracting it from wheat gluten proteins; these days, commercial MSG is produced using bacteria. In the United States, MSG must be listed as a separate ingredient on food products, but other sources of free glutamates can be included under the “natural flavorings” umbrella and in foods that claim “No MSG.”
When added to food, MSG boosts the umami charateristics of a dish without otherwise changing the flavor, making the taste richer and more savory. I tried some MSG on its own (just a few grains, and even that was a bit much); its taste is definitely not the same as salt, and it’s difficult to describe beyond “savory.” A little goes a long way.
Is MSG safe?
The term “Chinese Restaurant Syndrome” was coined in 1968 by Robert Ho Man Kwak who described unpleasant symptoms he felt after eating Chinese food and posited the cause to be either the wine used in cooking, the large amount of sodium contained in the dishes, or the use of MSG seasoning. However, only the latter hypothesis was ever investigated, and the association stuck despite repeated failure by researchers to demonstrate a legitimate association under rigorously controlled conditions.
For example, in a study from 1993, only one participant out of 71 had a reaction, and that individual–who self-identified as sensitive to MSG–was in the placebo group. In other studies, large doses of MSG given without food ellicited more responses than did a placebo, but these responses were infrequent and not reproducible. A report commissioned by the FDA in 1995 stated that an unknown percentage of the population may react to MSG when consuming more than 3 grams without food–but these reactions were varied and non-specific, based on anecdotal reports, and that quantity of MSG consumption is not realistically reproducible in a restaurant environment. Numerous government agencies have repeatedly determined that MSG is safe for human consumption. Tests exploring potential links between MSG and obesity or neurological disorders has so far been inconclusive.
In summary, while it is possible that consuming MSG is bad for a small percentage of the population, the quantity found in food is not enough to cause harm, and even people who claim to react negatively to MSG do not necessarily do so under the conditions of a controlled study. Note: Because it is sometimes derived from wheat, MSG is on the list of foods celiac patients should avoid.
Cooking with MSG and Umami-Rich Foods
Okay, so it doesn’t seem like there are any good reasons NOT to eat MSG. But does that mean it’s worth eating? Without question, umami is a delicious quality for a food to have, but it doesn’t have to come from MSG. How does commercially-produced MSG stand up to naturally-derived glutamates, like those found in tomatoes, cheese, and meat?
To test this out, I decided to make some hamburgers. I found a recipe for umami burgers that uses fish sauce to add depth of flavor. Fish sauce contains fermented anchovy extract, salt, and sugar, and is ubiquitous in Thai and Vietnamese cooking. Despite its contents, when used as a seasoning it does not impart an overly fishy taste.
I made three hamburger patties according to the umami burger recipe, using the exact same quantity of ground beef, black pepper, sugar, and garlic but changing the source of sodium. The first burger contained 2 teaspoons of fish sauce, the second a 1/4 teaspoon of MSG (the recomended amount to use per half-pound of meat), and the third a 1/4 teaspoon kosher salt (this was the control):
I cooked each burger for three minutes per side on high heat and served them on buns without condiments. My husband Andrew participated in the taste test with me: I labeled the burgers A, B, and C but did not tell him which was which. Then I went in the other room while he changed the order and labeled them 1, 2, and 3 so that we could connect them to the A, B, C labels, then brought the burgers in to me–so, neither of us knew which burger contained which ingredient.
I identified the salt burger correctly; it was the least interesting of the three. However, I mixed up the MSG and fish sauce burgers, and Andrew mixed up all three. We both liked the fish sauce burger best, which surprised Andrew because he doesn’t like fishy things. I enjoyed the MSG burger more than the salt burger, but it wasn’t as enjoyable as the fish sauce burger.
Harold McGee writes, “the most unfortunate aspect of the MSG saga is how it has been exploited to provide a cheap, one-dimensional substitute for real and remarkable foods.” After trying the different burgers, I’m inclined to agree. There is nothing wrong with adding a pinch of MSG to punch up the flavor in a dish, but it won’t make up for bland food. As it says right on the bottle, MSG is merely the “Essence of Umami.” Try fish sauce, soy sauce, mushrooms, tomatoes, or Parmesan for a richer experience.
On Food and Cooking, by Harold McGee