Hemoglobin A1C (HbA1c) Test
A hemoglobin A1c (HbA1c) test measures the amount of blood sugar (glucose) attached to hemoglobin. Hemoglobin is the part of your red blood cells that carries oxygen from your lungs to the rest of your body. An HbA1c test shows what the average amount of glucose attached to hemoglobin has been over the past three months. It's a three-month average because that's typically how long a red blood cell lives.
Why it's done
The Centers for Disease Control (CDC) recommends that adults over the age of 45 get tested to screen for diabetes and prediabetes. If your results are normal, you should repeat the test every 3 years. If your results show you have prediabetes, you should get tested every 1-2 years. You should also talk to your health care provider about taking steps to reduce your risk of developing diabetes. If you are under 45, you may need this test if you have certain risk factors. These include:
- Being overweight or obese
- High blood pressure
- History of heart disease
- Physical inactivity
You may also need an HbA1c test if you have symptoms of diabetes. These include:
- Increased thirst
- Increased urination
- Blurred vision
- Fatigue
How you prepare?
Unlike fasting or post meal blood sugar tests, no special preparation is needed for an HbA1c test. You do not need to fast. You can give a test sample at any time of the day. Also, do not miss your medicines on the day of getting tested.
What happens during an HbA1c test?
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
