The lab tests listed below are used to test for prediabetes. If your ranges are higher than listed below, you likely have diabetes. If your ranges are lower than listed below, you do not have prediabetes, but that doesn't mean you shouldn't continue to eat healthy and exercise. 

The lab tests below in red indicate a diabetes diagnosis. If you lab tests are within this range, contact your provider to discuss.


1. Centers for Disease Control and Prevention. Prediabetes. ​ 2018.

2. Centers for Disease Control and Prevention. Testing Basics ​ 2018.

Oral Glucose Tolerance Test

​Prediabetes can be diagnosed by the following tests:
- Glycosylated hemoglobin/Hemoglobin A1C Test (A1C)
- Fasting Plasma Glucose Test (FPG)
- Oral Glucose Tolerance Test (OGTT)

Hemoglobin A1C shows the average blood glucose level over a period of approximately three months. Patients are not required to fast or drink solutions prior to this test.

Fasting Plasma Glucose measures blood glucose levels while having nothing to eat or drink (hence "fasting") over a period of at least eight hours.

Oral Glucose Tolerance Test measures blood glucose levels at baseline and again two hours after drinking a sweetened solution,

If you have questions regarding your lab tests or your diagnosis, don't be afraid to ask your medical provider about your results. Your provider can further explain your results and the numbers associated with the lab results. 

The following risk factors increase your chances of prediabetes and developing Type 2 Diabetes:

  • Being overweight
  • Being age 45 or older
  • Having a parent or sibling who has Type 2 Diabetes
  • A previous Gestational Diabetes Diagnosis
  • Having had a baby with a birth weight of 9 or more pounds
Hemoglobin A1C 


Know Your Numbers

Fasting Plasma Glucose
Diabetes Risk Factors
Prediabetes Lab Tests

Prediabetes Lab Tests - Explained