The results should be available within 24 hours. The test measures the percentage of haemoglobin that is bound to glucose, which reflects the average blood glucose concentration over last few months. Abnormal results which would be higher than the normal range indicate a possible diagnosis of diabetes or poor control of diabetes.

If you are having an HbA1c test to help diagnose diabetes, a result of 6. A repeat test is often recommended to confirm the result, especially if you have no symptoms. Your doctor will also want to talk with you about your lifestyle, such as your diet and how much physical activity you usually do.

If you have known diabetes and your HbA1c is 6. Most doctors would recommend that people with diabetes should aim for this range. However, some people may have a target HbA1c range that is slightly higher than this.

If your levels are higher than your target range, that means that your blood sugar levels probably have not been well controlled recently. Your doctor will want to talk to you about your current treatments and whether any adjustments need to be made.

HbA1c is a simple blood test that does not require any fasting or other special preparation beforehand, and can be done at any time of the day. This is compared with other tests that can be used in the diagnosis of diabetes. A fasting blood sugar level, as the name implies, requires you to fast not eat food or drink for a certain period of time before having the blood test.

An oral glucose tolerance test is another way to diagnose diabetes. It requires a special diet for 3 days before having the test, and then fasting overnight before the test.

This test also involves having several blood tests over a couple of hours — before and after having to drink a certain volume of sweet liquid. The test is time consuming and some people find that drinking the liquid can make them feel sick. Most of us have type A haemoglobin HbA, or adult haemoglobin , but some people have a variant form of haemoglobin.

This is known as a haemoglobinopathy, and it can cause falsely high or low HbA1c results. Iron deficiency and iron deficiency anaemia can give a falsely high result; and haemolytic anaemia , blood loss, chronic ongoing liver disease and chronic kidney disease can give a falsely low HbA1c result.

The A1C test is useful for diagnosis, but it is also important for diabetes monitoring. Certain factors can cause inaccurate A1C results, including :.

Furthermore, certain people may have a less common type of hemoglobin that can affect the test results. This includes individuals of African, Mediterranean, or Southeast Asian descent, as well as people with blood disorders such as sickle cell anemia or thalassemia.

Average glucose, or eAG, is another way of reporting the results from an A1C test. Here is a comparison between the two scores based on a calculator from the American Diabetes Association ADA.

The ideal A1C level for a person can be a moving target. A doctor can make recommendations based on these factors. Individuals living with diabetes have a customized treatment plan.

An essential part of this plan involves a person self-monitoring their diabetes at home using a blood glucose meter or another device. This measurement is a snapshot of blood glucose levels at the time of the test.

Therefore, the levels vary depending on what a person eats, how much physical activity they do, and other factors, such as stress. Self-monitoring helps people manage their diabetes and allows them to track whether they are meeting their A1C target. It is important for people to manage blood sugar and A1C levels because experts associate increased levels with health complications, even if a person does not have diabetes.

Elevated A1C levels are a significant risk factor for cardiovascular diseases and stroke in people who may have diabetes. As A1C percentages rise, so does the risk of prediabetes becoming type 2 diabetes and complications arising in those who already have a diabetes diagnosis.

For example, in a large study , researchers found that the odds of developing type 2 diabetes increased fourfold for each percentage-unit increase in HbA1C.

People with diabetes need to manage their blood sugar levels to prevent them from becoming too high. Managing blood sugar levels can reduce the risk of complications affecting the small blood vessels, especially of the eyes and kidneys, and the coronary arteries. This can help to prevent the many problems that can occur with diabetes, including :.

However, everyone is different. An individual can work with a healthcare professional to determine their blood sugar and A1C targets. A doctor may suggest an A1C test at the beginning of pregnancy.

This can indicate whether or not someone with risk factors for diabetes has a high score. Later in the pregnancy, a doctor may test for gestational diabetes in other ways, as pregnancy can affect the A1C test result.

If a person has gestational diabetes , a doctor may also test up to 12 weeks after delivery. The ADA recommends regular A1C testing for people with diabetes.

For those without diabetes, the ADA recommends that anyone who is 45 years or more, or who is under 45 years but has risk factors for diabetes such as obesity, should seek a baseline test.

An individual may need to attend further testing, depending on the result of their baseline test. People who have had gestational diabetes during pregnancy may need to arrange a screening every 3 years. It is also useful for people to perform regular blood glucose tests at home and follow the correct treatment plan for diabetes between tests.

The A1C test measures the amount of hemoglobin in the blood with glucose attached. It provides a picture of average blood sugar levels over the previous 3 months and is a valuable tool for monitoring diabetes and diagnosing type 2 diabetes. Doctors use the A1C test to check for prediabetes and diabetes in individuals over They may also use the test for younger individuals if they are overweight or have other risk factors.

People living with diabetes typically have A1C tests several times per year. Read this article in Spanish. The A1C blood test measures how well the body maintains blood glucose levels by giving an average result for 2—3 months. When A1C levels fall, there…. What is a dangerously high A1C level?

Read on to learn more about the A1C test, what the results show, and how people can lower their A1C level.

Urine tests play a role in diagnosing diabetes and its complications. Both individuals and doctors can use them to monitor health and check for…. A study in mice suggests a potential mechanism that could explain why only some individuals with obesity develop type 2 diabetes.

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Medically reviewed by Angelica Balingit, MD — By Markus MacGill and Zia Sherrell, MPH — Updated on February 14, What is it? What to expect Who should get one? A1C results explained What can affect results?

What is the A1C test? What to expect. Who should get an A1C test? A1C results explained. What can affect A1C results?

Your GP or diabetes team will work with you to decide what target HbA1c is best for you. It's important to know your results and talk to your diabetes team about them. Maintaining a healthy and balanced diet and getting regular exercise will help get your HbA1c levels under control.

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Hemoglobin is the protein in red blood cells that transports oxygen around the body. Glucose attaches to hemoglobin to form glycated hemoglobin, which is also called hemoglobin A1C.

When blood sugar levels are high, the body creates more glycated hemoglobin. The A1C test measures these levels. Red blood cells live for around days , or 4 months, and the A1C test measures the average blood glucose level over their lifespan.

A person can take the A1C test at any time. They do not need to fast before taking it or do any other preparation.

To perform the test, a doctor or other healthcare professional will draw blood either from a finger stick or a bvein in the arm. They then send it to a laboratory for testing. While this may be useful for managing diabetes, the National Institute of Diabetes and Digestive and Kidney Diseases NIDDKD says that it is not suitable for diagnosis.

The A1C test is one of the tests doctors use to diagnose type 2 diabetes and prediabetes. They may also use other tests, such as a fasting blood glucose test or a 2-hour glucose tolerance test. For adults over 45 years or for people with certain risk factors, doctors repeat the A1C test every 3 years.

If the A1C test shows someone has prediabetes, they can make lifestyle changes to lower their risk for type 2 diabetes. A doctor may advise repeating the A1C yearly or every 2 years.

Additionally, people living with diabetes typically have their A1C levels monitored regularly. This can help them manage their medications and health. Learn more about preventing type 2 diabetes.

A1C test results show as a percentage. For diagnosis, the test results may be as follows :. One A1C test result does not mean that a person has diabetes. According to the NIDDK, if the A1C test shows 6. A doctor will repeat these tests if A1C results, glucose scores, or both suggest a person has diabetes.

A person with prediabetes has a higher chance of developing type 2 diabetes in the future, but lifestyle changes, such as quitting smoking , following a healthy diet , and taking regular exercise , can often reduce the risk.

The person may already have risk factors for type 2 diabetes, such as:. The A1C test is useful for diagnosis, but it is also important for diabetes monitoring. Certain factors can cause inaccurate A1C results, including :. Furthermore, certain people may have a less common type of hemoglobin that can affect the test results.

This includes individuals of African, Mediterranean, or Southeast Asian descent, as well as people with blood disorders such as sickle cell anemia or thalassemia. Average glucose, or eAG, is another way of reporting the results from an A1C test.

Here is a comparison between the two scores based on a calculator from the American Diabetes Association ADA. The ideal A1C level for a person can be a moving target. A doctor can make recommendations based on these factors.

Individuals living with diabetes have a customized treatment plan. An essential part of this plan involves a person self-monitoring their diabetes at home using a blood glucose meter or another device.

This measurement is a snapshot of blood glucose levels at the time of the test. Therefore, the levels vary depending on what a person eats, how much physical activity they do, and other factors, such as stress.

Self-monitoring helps people manage their diabetes and allows them to track whether they are meeting their A1C target. It is important for people to manage blood sugar and A1C levels because experts associate increased levels with health complications, even if a person does not have diabetes.

American Diabetes Association. A1C and eAG. Date Unknown. Understanding A1C. ARUP Consult. Diabetes Mellitus — Type 1, Type 2, and Gestational.

Updated July Brutsaert E. Diabetes Mellitus DM. Merck Manual Consumer Edition. Updated September Merck Manual Professional Edition. Centers for Disease Control and Prevention. All About Your A1C.

Updated August 10, What Is Diabetes? Updated July 7, Hayward RA, Selvin E. Screening for Type 2 Diabetes Mellitus. In: Elmore JG, Nathan DM, eds. Updated August 31, Horowitz GL, Ucciferro, P, Anastasopoulou, C.

Hemoglobin A1c Testing. Devaraj S, ed. Updated October 4, Inzucchi SE, Lupsa B. Clinical Presentation, Diagnosis, and Initial Evaluation of Diabetes Mellitus in Adults.

In: Nathan DM, Wolfsdorf JI, eds. Updated October 29, MedlinePlus: National Library of Medicine. Hemoglobin A1C HbA1c Test. Updated September 15, National Heart, Lung, and Blood Institute. Blood Tests. Updated March 24, National Institute of Diabetes and Digestive and Kidney Diseases.

Updated December Updated April Insulin Resistance and Prediabetes. Updated May Updated August Nielsen LR, Ekbom P, Damm P, et al. HbA1c Levels are Significantly Lower in Early and Late Pregnancy. Diabetes Care. Selvin E. Measurements of Glycemic Control in Diabetes Mellitus.

Updated February 15, Whitley HP, Yong EV, Rasinen C. Selecting an A1C Point-of-Care Instrument. Diabetes Spectr. This form enables patients to ask specific questions about lab tests. Your questions will be answered by a laboratory scientist as part of a voluntary service provided by one of our partners, American Society for Clinical Laboratory Science.

Please allow business days for an email response from one of the volunteers on the Consumer Information Response Team. Last modified on Sep 13, Hemoglobin A1C HbA1c Test Also Known As: A1C Test, Glycated Hemoglobin Test, HbA1C, Hgba1c, Hgb a1c.

Board Approved. Medically Reviewed by Thomas Kampfrath, PhD, DABCC, FAACC. Get tested. Test Quick Guide The hemoglobin A1c test estimates how much glucose, or blood sugar, has been in your bloodstream over the last three months.

About the Test Purpose of the test The hemoglobin A1c test may have several purposes: Screening for prediabetes and diabetes: If you are over 40 and are obese, overweight, or otherwise at high risk for diabetes, your doctor may want to check for health conditions before you experience symptoms.

The test can be used for diabetes screening, but the results may need to be confirmed by repeating the test or using another type of test.

Diagnosing prediabetes and diabetes: This uses tests and procedures to find out the cause of health changes. Your doctor may order hemoglobin A1c and other tests if you have symptoms or show signs of diabetes.

Symptoms can include excessive thirst, frequent urination, blurred vision, tingling or loss of sensation in the feet and hands, and feeling extremely tired. Monitoring diabetes: If you have been diagnosed with diabetes, your doctor may order this test at least twice a year.

This gives your doctor an idea of how well your blood glucose has been controlled in the months between appointments and allows your doctor to make adjustments to your treatment plan and lower your chance of health problems. What does the test measure? When should I get this test?

htm A. htm American Diabetes Association. html Centers for Disease Control and Prevention. html Hayward RA, Selvin E. See More. See Less. Table of Contents. Ask a Laboratory Scientist.

Send Us Your Question Send Us Your Question. This website uses cookies to ensure you get the best experience on our website. I Accept. On average it takes 7 working days for the blood test results to come back from the hospital, depending on the exact tests requested. Some specialist test results may take longer, if samples have to be sent to a reference specialist laboratory.

If you are registered to use the online services of your local practice, you may be able to access your results online. Your GP practice will be able to provide specific details. If the doctor wants to see you about the result s , you will be offered an appointment.

If you are concerned about your test results, you will need to arrange an appointment with your doctor so that all relevant information including age, ethnicity, health history, signs and symptoms, laboratory and other procedures radiology, endoscopy, etc.

Lab Tests Online-UK is an educational website designed to provide patients and carers with information on laboratory tests used in medical care.

We are not a laboratory and are unable to comment on an individual's health and treatment. Reference ranges are dependent on many factors, including patient age, sex, sample population, and test method, and numeric test results can have different meanings in different laboratories.

For these reasons, you will not find reference ranges for the majority of tests described on this web site.

The lab report containing your test results should include the relevant reference range for your test s. Please consult your doctor or the laboratory that performed the test s to obtain the reference range if you do not have the lab report. For more information on reference ranges, please read Reference Ranges and What They Mean.

Some of the glucose in your blood binds to haemoglobin the protein that carries oxygen in your red blood cells. This combination of glucose and haemoglobin is called haemoglobin A1c HbA1c.

The amount of HbA1c formed is directly related to the average concentration of glucose in your bloodstream. Red blood cells live for 2—3 months, and because of this, the amount of HbA1c in your blood reflects the average level of glucose in your blood during the last months.

If your diabetes is not well controlled, your blood glucose levels will be high causing higher HbA1c levels. The test for HbA1c shows how well your diabetes has been controlled over the last months.

Even though you may have some very high or very low blood glucose values, HbA1c will give a picture of the average level of glucose in your blood over that time period. The result can help you and your doctor understand if the measures you are taking to control your diabetes are working.

In the past the test was only used to monitor blood glucose control in patients with known diabetes. Now the World Health Organisation WHO recommendsthat HbA1c can also be used to diagnose type 2 diabetes in people who were not previously known to have the condition.

There are certain situations in which HbA1c cannot be used to diagnose diabetes. An oral glucose tolerance test would be used as an alternative. The Department of Health recommends that everyone with diabetes has HbA1c measured at least twice a year.

HbA1c may be measured more frequently in those who have just been diagnosed with diabetes, in those whose blood glucose remains too high, or when a treatment plan changes. The test can also be used to diagnose type 2 diabetes. Please speak to your healthcare professional about local guidelines that may be in place, as there maybe variations in local procedures.

If you have an uncommon type of haemoglobin , known as a haemoglobin variant for example thalassaemia or sickle cell disease , accurate results will depend on the method used to measure HbA1c.

If you have haemolytic anaemia or heavy bleeding, your test results may be falsely low. If you are iron deficient, this may raise your HbA1c result. HbA1c is not used for diagnosis of diabetes during pregnancy. HbA1c could be measured at home but this is rarely done, is expensive and should not be necessary if you are being monitored by your doctor.