Before you measure your fasting blood glucose, you should not eat anything, usually after you have used your dinner the night before. Fasting in medical terms means fasting for 8 to 10 hours. If a patient’s fasting blood glucose is measured at 8:00 a.m. the next day, he or she should not eat after 12:00 p.m. the night before at the latest. Patients who eat energy-containing foods, such as rice, steamed buns, stir-fried vegetables, fruits, coffee, etc., during this period of fasting will often result in inaccurate fasting blood glucose values. The normal range of fasting blood glucose is 3.9~6.1mmol/L. It is recommended that patients who need to measure fasting blood glucose try not to consume food during the fasting period, so as not to cause inaccurate measurements and delay the judgment of the disease.