Before people develop type 2 diabetes, they almost always have "prediabetes"—blood glucose levels that are higher than normal but not yet high enough to be diagnosed as diabetes. Normal fasting blood glucose is below 100 mg/dl. A person with prediabetes has a fasting blood glucose level between 100 and 125 mg/dl. If the blood glucose level rises to 126 mg/dl or above, a person has diabetes.
at 2:07 AM on Sep. 24, 2010