The etiology of diabetes is generally divided into four categories: 1 type diabetes, type 2 diabetes, pregnancy-related diabetes and other types of related diabetes. 1 Diabetes is mostly related to infection and immune abnormality; Type 2 diabetes refers to insulin resistance caused by lifestyle, obesity and other factors. About 90%-95% of China people have type 2 diabetes. The third type of diabetes is pregnancy-related diabetes, which is due to the influence of placental hormones during pregnancy and the increase of blood sugar caused by maternal lifestyle and metabolism. Other types of diabetes, including steroid diabetes caused by high doses of glucocorticoid, are now classified as other types of diabetes. There is also a type related to gene mutation, such as the common MODY, which was originally called type 2 diabetes among teenagers and later proved to be diabetes related to gene mutation.