An essential amino acid that is found in the heart, skeletal muscles and central nervous system. It is necessary to provide proper protein balance and aids in the formation of tooth enamel, collagen and elastin in the skin. It produces antibodies to help boost the immune system, and helps promote thymus growth and activity. It helps to absorb other nutrients. It helps keep skin healthy and promotes wound healing, aids in proper fat metabolism in the liver and helps the digestive and intestinal tracts function properly. It can also help to alleviate anxiety and in some cases depression.