Glucose tolerance may be unfamiliar to the average person, but for sugar lovers, this glucose tolerance is something that is all too familiar. The human glucose tolerance, commonly known as the body’s ability to tolerate glucose, is a laboratory test used to diagnose diabetes. The glucose tolerance test is very important and must be done for patients who are first diagnosed with diabetes, especially if it is not clear whether or not they have diabetes; for patients who have been diagnosed with diabetes, the glucose tolerance test and islet release test are also done when assessing insulin function. If the glucose tolerance test is between 7.8 and 11.1 mmol/L 2 hours after taking sugar, it indicates that the body’s ability to tolerate sugar is reduced, which means that the body’s absorption and utilization of sugar is worse than normal. The steps of the glucose tolerance test include: i. prepare 75g of glucose powder; ii. collect the specimen after the patient has fasted for 8-12 hours; iii. dissolve 75g of glucose in 300mL of warm boiled water and then drink it within five minutes, and collect the blood specimen at half an hour, one hour, two hours and three hours, respectively; iv. avoid strenuous exercise during the test. Through a total of five specimens to know the body’s blood glucose metabolism, in addition, pregnant women’s glucose tolerance test collection of blood specimens for fasting, 1 hour, 2 hours, except for all the same. If the glucose tolerance test is significantly abnormal and exceeds the normal range, there is a high probability that you have diabetes. Diabetes is the “cancer that never dies” and once it appears, it requires long-term medication to maintain treatment. Sugar control must be done well, otherwise there may be complications of diabetes, which is life-threatening. Diabetes is one of the “three highs”, as well as hypertension and hyperlipidemia, is a chronic disease that is extremely harmful to health and should not be ignored for treatment.