The 2-hour postprandial glucose measurement is mostly used for suspected diabetic patients. Clinically, for patients with insidious diabetes who have normal or slightly high fasting glucose, occasional urine sugar, and no obvious diabetic symptoms, the 2-hour postprandial glucose tolerance test is often used to make a clear diagnosis, which is often called the “2-hour postprandial glucose” measurement. However, the 2-hour postprandial glucose measurement does not require you to come to the blood test 2 hours after eating breakfast, because the amount of food (or sugar content, to be exact) is different for each person. Of course, if you come to the test 2 hours after eating breakfast, you can also judge the blood sugar. The correct method is to draw 2 ml of blood on an empty stomach, then take 75 grams of glucose and 250 ml of water orally within 5 minutes, and draw 2 ml of blood 2 hours after taking the glucose and send it for testing immediately. It is best to keep urine to measure urine sugar at the same time as the blood is drawn. Alternatively, 50 ml of 50% glucose can be administered intravenously and blood can be drawn and tested according to the oral method. It is very important to know the requirements for the 2-hour postprandial glucose measurement to ensure that you get the correct results. Normal postprandial blood glucose returns to fasting level 2 hours after taking sugar. If it does not fall to normal level 2 hours after taking sugar and the urine sugar is positive, it means that the glucose tolerance is reduced. Decreased glucose tolerance does not mean that you have diabetes, but there is a certain range. However, people with abnormal glucose tolerance are more likely to develop diabetes than normal people and should be highly alert.