MSG, or monosodium glutamate, is a flavor enhancer which is commonly added to Chinese food, canned vegetables, soups and processed meats. The Food and Drug Administration (FDA) has classified MSG as a food ingredient that is “generally recognized as safe”, but the use of MSG remains controversial. For this reason, whenever MSG is added to food, the FDA requires that it be listed on the label.
MSG has been used for decades as a food additive. Over the years, the FDA has received many anecdotal reports of adverse reactions to foods containing MSG, including headache, facial pressure or tightness, and chest pain.
However, researchers have found no definitive evidence linking MSG and these symptoms. Researchers acknowledge, however, that a small percentage of people may have short-term reactions to MSG that are usually mild and do not require treatment. The only way to prevent a reaction is to avoid foods containing MSG.