Monosodium Glutamate
Monosodium glutamate (MSG), also known as sodium glutamate, is the sodium salt of glutamic acid, one of the most abundant naturally occurring non-essential amino acids. Glutamic acid is found naturally in tomatoes, grapes, cheese, mushrooms and other foods. MSG is used in the food industry as a flavor enhancer with an umami taste that intensifies the meaty, savory flavor of food, as naturally occurring glutamate does in foods such as stews and meat soups.
The U.S. Food and Drug Administration has given MSG its generally recognized as safe (GRAS) designation. Some sources indicate that MSG is known to cause headaches and other feelings of discomfort, known as "Chinese restaurant syndrome," but the majority of studies fail to find evidence of such a reaction. However, some neurologists maintain that MSG may be a migraine trigger. Therefore, the European Union classifies it as a food additive permitted in certain foods and subject to quantitative limits.