Criteria for Diagnosing Diabetes

To be diagnosed with Reference diabetes Opens New Window, you must meet one of the following criteria:^{Reference 1}

• Have symptoms of diabetes (increased thirst, increased urination, and unexplained weight loss) and a blood sugar level equal to or greater than 200 Reference milligrams per deciliter Opens New Window (mg/dL). The blood sugar test is done at any time, without regard for when you last ate (random plasma glucose test or Reference random blood sugar test).
• Have a Reference fasting blood sugar level that is equal to or greater than 126 mg/dL. A fasting blood sugar test (fasting plasma glucose) is done after not eating or drinking anything but water for 8 hours.
• Have a 2-hour Reference oral glucose tolerance test (OGTT) result that is equal to or greater than 200 mg/dL. An OGTT is most commonly done to check for diabetes that occurs with pregnancy (gestational diabetes).
• Have a Reference hemoglobin A1c that is 6.5% or higher.

The diagnosis of diabetes needs to be confirmed by repeating the same blood sugar test or doing a different test on another day.

If the results of your fasting blood sugar test are between 100 mg/dL and 125 mg/dL, your OGTT result is between 140 to 199 mg/dL (2 hours after the beginning of the test), or your hemoglobin A1c is 5.7% to 6.4%, you have Reference prediabetes Opens New Window. This means that your blood sugar is above normal but not high enough to be diabetes. Discuss with your doctor how often you need to be tested.^{Reference 1}

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This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.