Out of 20 amino acids required for protein synthesis, human body can synthesize only 10. These ten amino acids which the body can synthesize are called non-essential or dispensable amino acids. The remaining ten amino acids (valine, leucine, isoleucine, phenylalanine, methionine, tryptophan, threonine, lysine, arginine and histidine) which the body cannot synthesize are called essential or indispensable amino acids. These must be supplied in the human diet.
Natural Amino Acids
