The reason why fasting blood sugar is higher than postprandial blood sugar may be related to the effect of drugs, such as taking hypoglycemic drugs before meals, eating too few meals or excessive postprandial blood sugar consumption due to excessive postprandial exercise, or eating more at dinner or eating more before bedtime and other factors that lead to elevated fasting blood sugar. 1. The role of drugs: diabetic patients such as taking hypoglycemic drugs before meals, affected by the effect of drugs, there may be postprandial blood glucose lower than fasting blood glucose. 2. Insufficient diet or excessive intensity of exercise after meals: leading to high blood glucose consumption, or even out of the low blood glucose, so that the postprandial blood glucose is lower than the fasting blood glucose. 3. Additional meals before going to bed or eating too much at dinner: leading to high fasting blood sugar the next morning. High blood sugar should be under the guidance of a doctor, reasonable control of diet, appropriate exercise, fasting blood glucose and postprandial blood glucose stabilized within a reasonable range, to reduce the occurrence of complications.