The best test to measure your diabetes risk
An HbA1c test gives doctors the broadest view of blood sugar levels.
- Reviewed by David M. Nathan, MD, Editorial Advisory Board Member, Harvard Health Publishing

Even if you don’t live with type 2 diabetes — persistently high levels of sugar (glucose) in the blood — you might have heard about a hemoglobin HbA1c (HbA1c) test. The HbA1c test, which reflects average blood sugar levels over time, helps doctors follow your blood sugar trends. Having that information can determine your risk of diabetes, how well the condition is controlled, and your risk for diabetes complications.
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About the Reviewer
David M. Nathan, MD, Editorial Advisory Board Member, Harvard Health Publishing
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