OGTT test, i.e. Glucose Tolerance Test, the specific method: firstly, fasting blood glucose is measured once, then 75g anhydrous glucose is dissolved in water, and blood glucose is measured 1 hour and 2 hours after drinking sugar water. Glucose tolerance test is a laboratory diagnostic method to diagnose diabetes. For the glucose tolerance test, it is necessary to fast for 10~12 hours, draw fasting venous blood, and then drink 75g of anhydrous glucose in water (or 82.5g of glucose containing crystalline water dissolved in 250~300ml). Start timing when you drink the first sip, finish it within 5 minutes, measure blood glucose 1 hour after drinking the sugar water, and measure blood glucose again in 2 hours. If the blood glucose is greater than or equal to 11.1mmol/L in 2 hours, and at the same time there are typical “three more and one less” symptoms, then it means that there is diabetes; if it is greater than or equal to 7.8mmol/L, less than 11.1mmol/L, it means that the glucose tolerance is abnormal. If you have abnormal glucose tolerance, you should consult an endocrinologist.