What is an oral glucose tolerance test?

An oral glucose tolerance test (OGTT) is a test done to see how well the body handles a standard amount of glucose. The OGTT measures the amount of glucose in your plasma before and two hours after drinking a large premeasured beverage containing glucose (typically 75 grams). A doctor can compare the before and after glucose levels to see how well the body processed the sugar.

An oral glucose tolerance test (also called the OGTT) is the main test for diagnosing gestational diabetes. It's a three-hour test that checks your blood glucose levels at test times to see how your body handles a special sweet drink. If your glucose levels are above normal at least twice during the test, you have gestational diabetes.

An oral glucose tolerance test measures the body's ability to use glucose, a type of sugar found in fruits and many other foods. (Glucose is the main source of energy used by the body.)

After not eating all night, the person being tested drinks a special sugar solution on the morning of the test. A blood sugar sample is taken from a vein in the person's arm once each hour for several hours to see how much the blood sugar increases and then decreases over time. The test is done in a doctor's office or lab.

The oral glucose tolerance test can be used to diagnose prediabetes and diabetes. It is used to diagnose gestational diabetes, which develops during pregnancy.

An oral glucose tolerance test (OGTT) measures how your body responds to a sugar "challenge." After fasting overnight, your fasting blood glucose is tested. You'll then be given a sugar solution to drink and your blood sugar will be tested over the next few hours. This test is used to diagnose all types of diabetes.

What test results mean:

Normal: Less than 140 mg/dL
Prediabetes: 141 to 199 mg/dL
Diabetes: Higher than 200 mg/L

Take the RealAge Test!