A1C test - Mayo Clinic

A1C test - Mayo Clinic

The A1C test result reflects your average blood sugar level for the past two to three months.

The A1C test is a common blood test used to diagnose type 1 and type 2 diabetes and to monitor how well you're managing your diabetes.

Specifically, the A1C test measures what percentage of your hemoglobin — a protein in red blood cells that carries oxygen — is coated with sugar (glycated).

Identify prediabetes.

Diagnose type 1 and type 2 diabetes.

The A1C test is a simple blood test. You don't need to fast for the A1C test, so you can eat and drink normally before the test.

A1C test results are reported as a percentage. A higher A1C percentage corresponds to higher average blood sugar levels.

For someone who doesn't have diabetes, a normal A1C level is below 5.7 percent. If your A1C level is between 5.7 and 6.4 percent, you have prediabetes (also called impaired fasting glucose), which means you have a high risk of developing diabetes in the future.

An A1C level of 6.5 percent or higher on two separate occasions shows that you have diabetes.