what is a1c lab test

The A1C test, also known as the hemoglobin A1C or HbA1c test, is a blood test that measures your average blood sugar levels over the past 2 to 3 months. It is commonly used to diagnose prediabetes and diabetes, as well as to monitor how well you are managing your condition if you already have diabetes.

How Does the A1C Test Work?

• The test measures the percentage of your red blood cells that have sugar-coated hemoglobin.
• Hemoglobin is a protein in red blood cells that carries oxygen. When glucose enters your bloodstream, it attaches to hemoglobin.
• The higher your blood sugar levels, the more glucose attaches to hemoglobin.
• Red blood cells regenerate every 3 months, which is why the A1C test reflects your average blood sugar levels over that period.

A1C Results and What They Mean

• Normal: Below 5.7%
• Prediabetes: 5.7% to 6.4%
• Diabetes: 6.5% or above

Why Is the A1C Test Important?

• It provides a long-term view of your blood sugar levels, unlike daily glucose checks, which only show a snapshot.
• It helps healthcare providers assess your risk for diabetes-related complications.

For more detailed information, you can visit the CDC's A1C Test page.