(Science: amino acid) Is synthesised by the body from the amino acids glycine or threonine. Its production requires adequate amounts of B-7 (niacin), B-6 and folic acid. It is needed for the metabolism of fats and fatty acids, muscle growth and a healthy immune system. It aides in the production of immunoglobulins and antibodies. It is a constituent of brain proteins and nerve coverings. It is important in the formation of cell membranes, involved in the metabolism of purines and pyrimidines and muscle synthesis. It is also used in cosmetics as a skin moisturizer. Serine is abundant in meats and dairy products, wheat gluten, peanuts and soy products, all of which are common allergens. There is some concern that elevated serine levels can cause immune suppression and psychological symptoms as in cerebral allergies.