Cystine is an indispensable amino acid in the body and has many effects on the body: 1. Promotes cellular oxidation and reduction functions, makes the liver function vigorous, promotes the liver’s detoxification ability, and has a protective effect on the liver; 2. Promotes the hematopoietic function of the blood system and promotes the proliferation of white blood cells; 3. Improves immunity, prevents the development of pathogenic bacteria, and plays a role in the body barrier; 4. Aids insulin and plays a role in lowering sugar in cooperation with insulin; 5. Cystine can release sulfuric acid when metabolized, which generates physiological and biochemical reactions with other substances and strengthens the detoxification ability of the metabolic system; 6. Cystine can reduce the body’s ability to absorb copper, protects cells, and avoids copper poisoning.