A1C is a blood test that measures your average blood sugar levels over the past 3 months. It's one of the commonly used tests to diagnose prediabetes and diabetes, and is also the main test to help you and your health care team manage your diabetes.
A1C is a protein in your blood cells that carries oxygen. When you have diabetes, your blood sugar levels are too high. This can cause sugar to attach to your A1C molecules. The more sugar that attaches to your A1C molecules, the higher your A1C level will be.
A1C levels are reported as a percentage. A normal A1C level is 4% or less. A prediabetes A1C level is 5.7% to 6.4%. A diabetes A1C level is 6.5% or higher.
If you have diabetes, your doctor will use your A1C levels to help you manage your blood sugar levels. They may also use your A1C levels to help you track your progress over time.
A1C is a simple blood test that can help you and your doctor manage your diabetes.