Morning fasting blood glucose, reflecting the function of pancreatic islet B-cells, is the most commonly used testing indicators of diabetes, the normal value of fasting blood glucose in normal adults in the range of 3.9 ~ 6.1mmol / L. Normal people have stable pancreatic islet cell function, which can metabolize the glucose output from liver glycogen, and have stable blood glucose control, with normal values ranging from 3.9~6.1mmol/L. Fasting blood glucose 6.1mmol/L~6.9mmol/L is considered to be impaired fasting glucose regulation. Clinically, impaired fasting blood glucose is considered to be an abnormality of glucose metabolism, and most of the patients will eventually progress to diabetes. If fasting blood glucose ≥7.0mmol/L, together with the typical symptoms of diabetes mellitus, the diagnostic standard of diabetes mellitus has been reached. Once abnormal blood glucose values occur, it is recommended to consult the endocrinology department of a regular hospital in a timely manner and follow the doctor’s instructions for treatment.