A normal glucose tolerance test rules out diabetes in most cases. Glucose tolerance test is a way to diagnose diabetes, before and after taking 75 grams of oral glucose to measure the value of blood sugar, if normal, most can rule out diabetes. Diabetes can be diagnosed if there is a significant increase in blood glucose, with fasting blood glucose greater than or equal to 7.0mmol/l or 2 hours after meals blood glucose greater than or equal to 11.1mmol/l combined with symptoms of diabetes such as excessive drinking, excessive urination and dry mouth. If the blood sugar is mildly elevated, it may be pre-diabetes, which requires active dietary control, more exercise, and improved lifestyle to avoid progression to diabetes. Usually still need to maintain a good lifestyle, low-salt and low-fat diet, especially for people with a family history of diabetes, the need for long-term monitoring of blood glucose, found that elevated blood glucose should be timely to the hospital, under the guidance of the doctor early diagnosis, early treatment.