How to Diagnose Prediabetes

Prediabetes, a medical condition that often precedes type 2 diabetes, is the state of having elevated blood glucose levels. People with prediabetes have a fasting blood glucose level between 100 and 125 mg/dL, according to the Mayo Clinic. Levels of 126 mg/dL or higher indicate diabetes. Diagnosis of prediabetes is confirmed through a series of lab tests.

Things You'll Need

• Blood tests

Show More

Instructions

• 1

  Understand that the majority of people who have prediabetes do not show symptoms of the condition, according to the CDC. Some people find themselves very hungry and thirsty or tired when their glucose levels are elevated. These are classic signs of diabetes, along with unexplained weight loss, blurry vision, and an increase in urination, reports the Mayo Clinic.

• 2

  Take a hemoglobin A1C blood test. This simple test measures the level of glucose that attaches itself to your hemoglobin cells. The reading indicates your average blood glucose levels over the previous 2 to 3 months. If you have prediabetes, your A1C results will fall into the range between 6 and 6.5 percent.

• 3

  Undergo an impaired fasting glucose test. This blood test measures your glucose level after you have fasted for at least eight hours, according to the Centers for Disease Control and Prevention. Normal results for this test are below 100 mg/dL. Levels of 100 to 125 mg/dL indicate prediabetes. Try to have the test done first thing in the morning if going without food for long periods of time is a concern.

• 4

  Diagnose prediabetes with an impaired glucose tolerance test. Your blood will be drawn and assessed for glucose levels after an 8-hour fast. After the blood draw, you will drink a very sweet beverage (given to you by the lab), and wait for 2 hours. At the 2-hour mark, your blood glucose will be measured again. Normal readings are under 140 mg/dL. Prediabetes is the diagnosis for readings between 140 and 199 mg/dL.