Prediabetes can return to normal in 2 to 3 months if active intervention is available, but the exact recovery time varies with the patient’s condition. Diabetes mellitus is a group of metabolic disorders characterized by chronic hyperglycemia caused by absolute or relative insulin insufficiency or (and) impaired insulin utilization. Pre-diabetes usually refers to a condition in which blood glucose levels appear elevated, but have not yet met the diagnostic criteria for diabetes. When a patient is in pre-diabetic state, if it is caused by poor lifestyle or obesity, lifestyle intervention can be carried out first, such as dietary control, exercise, etc., avoiding the intake of food with high content of fat and sugar, actively participating in jogging, swimming and other sports, and controlling the body weight, usually the patient’s blood glucose level can be returned to normal within 2 to 3 months. If the glycosylated hemoglobin value as well as the values of fasting blood glucose and 2-hour postprandial blood glucose are persistently high, it is recommended that further examination be conducted to find out whether the patient has reached the stage of diabetes mellitus.