Myostatin belongs to small molecule polypeptide, small molecule polypeptide is protein residue, also protein fragment. Small molecule peptide has many efficacy and function to human body: 1. It has the function of regulating immunity, and can regulate the disease of patients with hyperimmunity or hypoimmunity. Myostatin can play a good role in regulating the construction of human immunity barrier, whether it is cellular immunity or humoral immunity.2. Myostatin can also maintain the endocrine balance of human body, in the case of endocrine and metabolic diseases, proper supplementation of myostatin has the role of regulating the endocrine level in the body.3. Myostatin also has a certain role of nourishing the body, which can nourish the brain tissue of human body and improve the growth of brain neurotransmitters. It can also nourish the nerve endings, which can play the role of nourishing neurons and nourishing nerves.