What is a 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.
If your HbA1c levels are high, it may be a sign of diabetes, a chronic condition that can cause serious health problems, including heart disease, kidney disease, and nerve damage.
Other names: HbA1c, A1c, glycohemoglobin, glycated hemoglobin, glycosylated hemoglobin
What is it used for?
An HbA1c test may be used to check for diabetes or prediabetes in adults. Prediabetes means your blood sugar levels show you are at risk for getting diabetes.
If you already have diabetes, an HbA1c test can help monitor your condition and glucose levels.
Why do I need an HbA1c test?
You may need an HbA1c test if you have symptoms of diabetes. These include:
- Increased thirst
- Increased urination
- Blurred vision
- Fatigue
Your health care provider may also order an HbA1c test if you are at higher risk for getting diabetes. Risk factors include:
- Being overweight or obese
- High blood pressure
- History of heart disease
- Physical inactivity