A blood sugar of more than 10 points before meal is suspected to be diabetes, and the diagnosis should be confirmed after completing the relevant tests, including fasting blood sugar, 2-hour blood sugar after meal, etc. Treatment after diagnosis of diabetes mellitus includes diet control, exercise therapy and medication. Pre-meal blood glucose may refer to fasting blood glucose or blood glucose before lunch or dinner. Normally, blood glucose three to four hours after a meal should be close to fasting blood glucose. Diabetes is diagnosed when fasting blood sugar exceeds 7.0 mmol/L, along with diabetic symptoms such as excessive drinking, excessive eating, excessive urination, and weight loss. Therefore, preprandial blood glucose 10 points or more should be suspected of diabetes, and it is recommended to improve the fasting blood glucose, postprandial 2 hours blood glucose, glucose tolerance, glycated hemoglobin and other related tests to clarify the diagnosis. After diagnosis of diabetes mellitus, dietary control is needed, such as controlling total calorie intake and avoiding high-fat and high-sugar foods; appropriate exercise, including running and swimming; and treatment with glucose-lowering drugs such as metformin or insulin injections. Abnormal blood glucose values are recommended to go to the hospital and ask the doctor to make a judgment.