Last Updated on July 28, 2022 by Dr. Neeraj Gujar
The hemoglobin A1c test, also known as the HbA1c test, measures blood sugar (glucose). Hemoglobin is a part of your red blood cells that transports oxygen from your lungs to your body. The HbA1c test measures the average glucose content of hemoglobin over the last three months. Because that is how long red blood cells live, it’s usually a three-month average.
High HbA1c levels may indicate diabetes. This chronic condition can lead to serious health problems such as heart disease and kidney disease.
The A1C blood test measures blood glucose levels over the past 3 months. The A1C test is used by doctors to assess the stability of a patient’s blood sugar levels. They can also use it in the initial diagnosis of type 2 diabetes.
The A1C test can also be called:
HbA1c, A1c, glycohemoglobin, glycated hemoglobin, glycosylated hemoglobin
Why Test Is Done?
An HbA1c test can be used to determine if you have diabetes or prediabetes. Prediabetes is a condition in which your blood sugar levels indicate that you are at high risk of developing diabetes.
An HbA1c test is a good way to monitor diabetes and your glucose levels.
Also Read: Do You Need to Be Concerned If Your Hemoglobin Isn’t In Normal Range?
When Get Tested?
The test helps to diagnose type 2 diabetes or prediabetes. Other tests may also be used, including a fasting glucose test and a 2-hour glucose tolerance test.
The Centers for Disease Control (CDC), recommends that all adults over 45 be tested for diabetes and prediabetes. You should have the test repeated every three years if your results are not abnormal. If you are diagnosed with prediabetes, it is a good idea to have your blood tested every 2 years. Talk to your doctor about ways to lower your chance of developing diabetes.
This test may be required if you are younger than 45 years old in case of:
- High blood pressure
- Being overweight or obese
- Physical inactivity
- History of Heart Disease
If you are diagnosed with prediabetes, testing should be performed every three years.
If you have diabetes symptoms, an HbA1c test may be required. These include:
- Increase in thirst
- Blurred vision
- Increased urination
How To Get Tested?
The test is done in a doctor’s office or a lab using a sample of blood from a finger stick or your arm. You can also opt for a blood test at home services for sample collection.
Before the Test
You don’t need any special preparations for an HbA1c test.
During the Test
A small needle is used by a health professional to take blood from a vein on your arm. Once the needle has been inserted, some blood will be taken and stored in a vial or test tube. The needle may cause a slight stinging sensation when it is inserted or removed. It usually takes less than five minutes.
After The Test
A blood test is not a risky procedure. Although you may feel a little bit of pain or bruise around the site where the needle was inserted, most symptoms disappear quickly.
A1c results are expressed as a percentage. The A1c test results show how much hemoglobin has been bound to your blood.
The following test results can be used for diagnostic purposes:
- Normal – HbA1c lower than 5.7%
- Prediabetes – HbA1c between 5.7% & 6.4%
- Diabetes – HbA1c at 6.5% or more
You may get different results. Talk to your doctor if you have any questions about your results.
Also Read: What is a Fasting Before Sugar (FBS) Test Result and What Does it Mean?
The American Diabetes Association recommends that your HbA1c levels stay below 7% if you have diabetes. Your overall health, age, and weight may influence your health care provider’s recommendations.
An HbA1c level of 6.5% or higher can be a sign that you may have diabetes even if you have never been diagnosed with it. You might need to have other tests done to determine if you have diabetes.
Your doctor will aim for an HbA1c between 6.5 and 7% if you have diabetes. Your doctor might recommend closer monitoring or changing your treatment if your HbA1c is higher than the target range.
Some medical conditions, like anemia, can alter red blood cells and impact your HbA1c results. Discuss the results with your doctor to understand what they mean for you.
Other medical conditions and factors that can alter the HbA1c results and lead to higher levels are:
- Liver disease
- Recent blood loss/transfusion
- Low iron levels
- Kidney disease
- Certain blood-related conditions
To analyze the results, your doctor is the best person to consult.
The A1C test measures hemoglobin levels in the blood. It also includes glucose. This test provides an overview of the average blood sugar over the past 3 months. It is useful for diagnosing and monitoring type 2 diabetes.
The A1C test is used by doctors to detect diabetes and prediabetes in people over 45. If a person is overweight or has other risk factors, they may use the A1C test to check for diabetes in younger people. A1C testing is often performed several times per year for people with diabetes.
Also Read: Top 9 Annual Blood Tests to Keep You Healthy and Active
The test is done as a regular check-up, especially if you are above 45 years of age. Your doctor may also suggest in case of symptoms or during pregnancy.
Though not necessary, fasting for at least 8 hours before the test is recommended.
A high HbA1c means you have too much sugar in your blood. It also means that you are more likely to develop diabetes or serious problems with the eyes and feet.
The FBS test, also known as the fasting blood sugar test, measures your blood glucose level at a single point in time. It is recommended to have this test in the morning after you fast for at least 8 hours for the most reliable results.
- AskMayoExpert. Type 2 diabetes mellitus (adult). Mayo Clinic; 2018.
- Diabetes overview. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/diabetes/overview/all-content.
- The A1C test and diabetes. (2018).
- All about your A1C. (2021).