what is a 1c

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
• Monitor blood sugar control in people with diabetes

How It Works

• 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 sugar enters your bloodstream, it attaches to hemoglobin.
• The higher your blood sugar levels, the more sugar-coated hemoglobin you will have.

A1C Results

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

Why It’s Important

• The A1C test provides a long-term view of blood sugar levels, unlike daily blood sugar checks, which only show a snapshot.
• It helps healthcare providers assess how well diabetes is being managed and adjust treatment plans if necessary.

For more details, visit the CDC's A1C Test page.