The normal range of fasting blood glucose at the age of 67 is 3.9-6.1 mmol/L, two-hour postprandial blood glucose is less than 7.8 mmol/L, and random blood glucose is less than 11.1 mmol/L. The monitoring of blood glucose includes fasting blood glucose, random blood glucose, two-hour postprandial blood glucose, etc. The diagnostic criteria for diabetes mellitus: diabetes mellitus can be diagnosed if fasting blood glucose ≥ 7.0 mmol/L, or two-hour postsugar load blood glucose ≥ 11.1 mmol/L, or random blood glucose ≥ 11.1 mmol/L, accompanied by three more and one less symptom (more drinking, eating, urinating, and weight loss). If there are no symptoms of diabetes, a diagnosis of diabetes is also considered if fasting blood glucose ≥7.0 mmol/L or two-hour postprandial blood glucose ≥11.1 mmol/L is monitored twice on non-same day. If blood glucose is elevated, it needs to be examined and treated under the supervision of a physician.