Monosodium glutamate (MSG) is the salt of the amino acid glutamate. Essentially, it is comprised of one sodium atom and one glutamate amino acid. MSG is a flavor enhancer added to many commercially packaged foods.
MSG may be found in foods such as flavored chips and crackers, bouillons and salad dressings. MSG has come under controversy due to its possible side effects that may include headaches, nausea and intense thirst. There have also been FDA advisories for those with asthma. Proponents of MSG argue it is similar to the glutamate produced in the body and it enables manufacturers to keep costs low while enhancing the flavor of foods.