what is hb1ac test

The HbA1c test, also known as the A1C test or hemoglobin A1C 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 Does It Work?

• The test measures the percentage of hemoglobin (a protein in red blood cells) that is coated with sugar (glycated hemoglobin).
• Red blood cells regenerate every 3 months, so the test reflects your average blood sugar levels over that period.

A1C Results and What They Mean:

A1C Level (%) Diagnosis

Below 5.7% Normal
5.7% - 6.4% Prediabetes
6.5% or above Diabetes

Why Is It 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 CDC's A1C Test Page.