Q: What is ‘MSG’ and is it harmful?
A: Monosodium glutamate (MSG) is a compound added to foods to enhance natural flavors. It’s made of glutamate, water and sodium. As a building block of proteins, the amino acid glutamate is found naturally in a wide variety of foods. Glutamate is also produced by the human body.
Glutamate from MSG is metabolized in our system in the same way as naturally-occurring glutamate. American consumption of MSG is estimated to be about 0.55 grams per day, though Taiwanese intake averages roughly 3 grams daily. A U.S. government committee on food additives evaluated MSG in the late ‘80s and concluded that the substance does not represent a health hazard for the general population. In one study, adult men consumed diets containing up to 147 grams MSG daily (200-300 times higher than normal consumption) for up to 42 days and researchers observed no adverse reactions to this dosage (Bazzano et al, 1970).
Surprisingly, MSG contains less sodium than table salt. MSG is 14% sodium, while the salt shaker holds 40% sodium. Therefore, MSG can actually be used instead of salt to obtain the same palatability.
So why the bad reputation? The late 1960’s saw a flurry of reports that consumption of large amounts of MSG causes flushing, lightheadedness, facial pressure and chest tightness. This cluster of reactions has been dubbed Chinese Restaurant Syndrome (CRS). However, well-designed experiments of the past decade have not been able to attribute CRS symptoms to MSG. It is possible, however, that some individuals may, in fact, be sensitive to MSG after ingesting greater than 3 grams in the absence of food.
Asian cuisine is not the only place you will find MSG! Even Italian dishes contain it and some highly-seasoned restaurant meals may contain up to 5 grams. MSG is available for purchase in the spice section of many supermarkets, and on packaged foods labels, you can find the ingredient listed as “monosodium glutamate.”