The HbA1c (Hemoglobin A1c) test is a blood test that provides an average of your blood glucose (sugar) levels over the past two to three months. It measures the percentage of your red blood cells that have sugar-coated hemoglobin, a protein that carries oxygen.
This test is a crucial tool for diagnosing prediabetes and type 2 diabetes. It is also used to monitor how well a person with diabetes is managing their condition. Unlike a regular blood glucose test which shows a single snapshot, the HbA1c provides a longer-term picture. No fasting is required for the test, as it's not affected by recent food intake.
Normal HbA1c is below 5.7%. Prediabetes is a result of 5.7% to 6.4%, while a diagnosis of diabetes is typically made with a result of 6.5% or higher.