Blood glucose returns to normal 5 hours after a meal, and the cause needs to be clarified, such as postprandial blood glucose elevation. Generally people’s blood sugar peaks half an hour to one hour after a meal, with a maximum of no more than 11.1 mmol/L, and returns to normal about 3 hours after the meal. If blood glucose returns to normal 5 hours after a meal, it may suggest that blood glucose is elevated after the meal, or that the food consumed is absorbed slowly and the sugar rises more slowly. Patients should monitor their blood glucose several times, record the values of blood glucose at different times after food and meals, clarify the causes under the guidance of the doctor, adjust the diet, and use medication if necessary.