The normal insulin value for each time of glucose tolerance test, the normal fasting blood glucose value is 3.9~6.1 mmol/L, the blood glucose value 1 hour after taking sugar is 6.7~9.5 mmol/L, the blood glucose value 2 hours after taking sugar is ≤7.8 mmol/L. However, if the instrument is different, the result of the experiment will be slightly deviated, so it is recommended to consult a doctor. Glucose tolerance test generally refers to oral glucose tolerance test, after taking 75g of anhydrous glucose orally, the blood glucose values of fasting, 1 hour after taking glucose, 2 hours after taking glucose, 3 hours after taking glucose are measured, and the main tests are generally fasting glucose, 2 hours after taking glucose blood glucose value. In addition, oral glucose tolerance test will be affected by some factors, such as excessive diet control before the test will appear false negative, in addition, cigarettes, alcohol, strong tea will also have an impact on the test value. Patients are advised to consult a specialist before undergoing an oral glucose tolerance test to avoid any impact on the results. Consult a doctor if you feel unwell during the oral glucose tolerance test.