What is HbA1c?

HbA1c, or hemoglobin A1c, is a blood test that measures your average blood sugar levels over the past 2 to 3 months. It is commonly used to diagnose and monitor diabetes and prediabetes. Here’s how it works:

• How it works: Glucose in your blood attaches to hemoglobin, a protein in red blood cells. The HbA1c test measures the percentage of hemoglobin that is coated with glucose.
• Normal range:
  • 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 blood sugar tests, which only show a snapshot.

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