what is a hgb a1c test

The Hemoglobin A1C (HbA1c) test, also known as the A1C 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 diabetes over time.

How Does It 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 (sugar) 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

A1C Level (%) Diagnosis

Below 5.7 Normal
5.7 - 6.4 Prediabetes
6.5 or higher Diabetes

Why Is It Important?

• The A1C test provides a long-term view of blood sugar control, unlike daily blood sugar checks, which only show a snapshot.
• It helps healthcare providers adjust treatment plans for diabetes management.

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