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Glycohemoglobin (HbA1c, A1c)

A glycohemoglobin test, or hemoglobin A1c, is a blood test that checks the amount of sugar (glucose) bound to the hemoglobin camera.gif in the red blood cells. When hemoglobin and glucose bond, a coat of sugar forms on the hemoglobin. That coat gets thicker when there's more sugar in the blood. A1c tests measure how thick that coat has been over the past 3 months, which is how long a red blood cell lives. People who have diabetes or other conditions that increase their blood glucose levels have more glycohemoglobin (sugar bound to hemoglobin) than normal.

An A1c test can be used to diagnose prediabetes or diabetes. The A1c test checks the long-term control of blood glucose levels in people with diabetes. Most doctors think checking an A1c level is the best way to check how well a person is controlling his or her diabetes.

A home blood glucose test measures the level of blood glucose only at that moment. Blood glucose levels change during the day for many reasons, including medicine, diet, exercise, and the level of insulin in the blood.

It is useful for a person who has diabetes to have information about the long-term control of blood sugar levels. The A1c test result does not change with any recent changes in diet, exercise, or medicines.

Glucose binds to hemoglobin in red blood cells at a steady rate. Since red blood cells last 3 to 4 months, the A1c test shows how much glucose is in the plasma part of blood. This test shows how well your diabetes has been controlled in the last 2 to 3 months and whether your diabetes treatment plan needs to be changed.

The A1c test can also help your doctor see how big your risk is of developing problems from diabetes, such as kidney failure, vision problems, and leg or foot numbness. Keeping your A1c level in your target range can lower your chance for problems.

Why It Is Done

This test is done to:

  • Diagnose prediabetes and diabetes.
  • Check your treatment for diabetes.
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WebMD Medical Reference from Healthwise

Last Updated: October 07, 2013
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.

People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

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