The traditional Chinese flavor enhancer can be added to vegetables, sauces, stews and soups to provide a more intense taste.
MSG is derived from the amino acid glutamate, or glutamic acid, which is one of the most abundant amino acids in nature.
Glutamic acid is a non-essential amino acid, meaning that your body can produce it. It serves various functions in your body and is found in nearly all foods. Chemically, MSG is a white crystalline powder that resembles table salt or sugar. It combines sodium and glutamic acid, known as a sodium salt. The glutamic acid in MSG is made by fermenting starches, but there is no chemical difference between the glutamic acid in MSG and that in natural foods.
MSG enhances the savory, meaty umami flavor of foods. Umami is the fifth basic taste, along with salty, sour, bitter and sweet. This additive is popular in Asian cooking and used in various processed foods in the West.
The average daily intake of MSG is 0.55–0.58 grams in the US and UK and 1.2–1.7 grams in Japan and Korea.
[Info from Healthline.com]