what is hemoglobin a1c blood test

The Hemoglobin A1C (HbA1c) test is a blood test that measures your average blood sugar (glucose) levels over the past 2 to 3 months. It is commonly used to diagnose prediabetes and diabetes, as well as to monitor how well your diabetes is being managed.

How It Works:

• Glucose in your blood attaches to hemoglobin, a protein in red blood cells.
• The A1C test measures the percentage of your red blood cells that have glucose-coated hemoglobin.
• Since red blood cells regenerate every 3 months, the test reflects your average blood sugar levels over that period.

A1C Results:

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

Why It’s Important:

• It provides a long-term view of blood sugar control, unlike daily glucose tests that only show a snapshot.
• It helps healthcare providers adjust treatment plans for diabetes management.

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