Diagnosing diabetes

Diabetes is diagnosed using blood tests that measure the glucose (sugar level) in the blood. Two tests are used.

These tests show whether the blood glucose level is too high. If it is, a person is diagnosed with diabetes.

Diagnosis Fasting test Casual test
Diabetes 126 mg/dL or higher 200 mg/dL or higher and symptoms
Normal Less than 100 mg/dL Less than 140 mg/dL

Some people have blood glucose levels higher than normal, but not high enough to be diabetes. This is known as prediabetes. People with prediabetes are at risk for diabetes.

Gestational diabetes

Gestational diabetes is diagnosed using an oral glucose tolerance test. All pregnant women without diabetes need to take this test. If two of the tests are higher than the values shown in the table below, a woman has gestational diabetes.

Test time Plasma blood glucose
Fasting (before drinking a glucose solution) 95 mg/dL or higher
One hour after drinking a glucose solution 180 mg/dL or higher
Two hours after drinking a glucose solution 155 mg/dL or higher
Three hours after drinking a glucose solution 140 mg/dL or higher

To make an appointment with International Diabetes Center, call 952-993-3393 or toll-free at 888-825-6315.