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HealthInfo Canterbury

Understanding your HbA1c results

The HbA1c blood test is used to find out if you have diabetes or prediabetes. It is also used to check how well‑controlled your diabetes is, if you have it.

The HbA1c blood test measures the amount of glucose (sugar) attached to your red blood cells. The more glucose in your blood, the higher the reading will be. A blood cell lasts for two to three months, so the HbA1c shows the average of your blood glucose levels over this length of time.

Normal HbA1c

A result of 40 or lower is normal for people without diabetes.

If you already have diabetes, the blood test will show how well you are controlling your blood glucose (sugar) levels. You will have a target to aim for, but your target will depend on your age, type of diabetes, and other health problems. Ask your GP what your personal target is. For most people it will be between 50 and 55.

prediabetesDiagnosing diabetes with HbA1c

If your result is between 41 and 49 then you have prediabetes.

If your result is 50 or higher then you have diabetes.

If your result shows that you have prediabetes, you should make changes to have a healthier lifestyle. This means eating healthy food, and keeping physically active. You will have another test in six to 12 months to see if these changes have made a difference.

If your results shows that you have diabetes, you will need to see your GP to talk about treatment options. This usually involves changing what you eat, other lifestyle changes, and tablets to lower your blood sugar levels. It may also mean you have to start insulin treatment.

Monitoring diabetes using HbA1c

If you have diabetes, your GP or diabetes clinic team will use your HbA1c to check how well‑controlled your blood glucose has been.

They will discuss a HbA1c target range for you to aim for.

If you need advice about eating well and lifestyle, or if you want to know more about diabetes, you can check the diabetes section or talk to your practice nurse or GP.

Written by HealthInfo clinical advisers. Last reviewed July 2019.


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Review key: HIUTR-269145