D-chiro-inositol (DCI) is one of the nine isomers of inositol and is optically active. In recent years, studies have found that d-inositol (DCI) not only has the function of inositol to promote lipid metabolism in the liver, but also has special physiological functions. It has the functions of lowering blood sugar, improving ovulation in patients with polycystic ovary syndrome (PCOS), regulating hormone balance, improving menstrual disorders, anti-oxidation, anti-aging, and anti-inflammatory.