What is HbA1c? | Blood Test | Target Levels

HbA1c is your average blood glucose (sugar) levels for the last two to three months. If you have diabetes, an ideal HbA1c level is 48mmol/mol (6.5%) or below.

If you’re at risk of developing type 2 diabetes, your target HbA1c level should be below 42mmol/mol (6%).

On this page we’ll go through what HbA1c means, and why aiming for your target level is so important. We’ll also explain the HbA1c test in more detail, and show you what you can do to lower your HbA1c levels if they’re too high. Plus, you can use our HbA1c converter tool if you’re looking to find out your level in % or mmol/mol. 

What does HbA1c mean?

HbA1c is what’s known as glycated haemoglobin. This is something that’s made when the glucose (sugar) in your body sticks to your red blood cells. Your body can’t use the sugar properly, so more of it sticks to your blood cells and builds up in your blood. Red blood cells are active for around 2-3 months, which is why the reading is taken quarterly.

A high HbA1c means you have too much sugar in your blood. This means you’re more likely to develop diabetes complications, like serious problems with your eyes and feet.

Knowing your HbA1c level and what you can do to lower it will help you reduce your risk of devastating complications. This means getting your HbA1c checked regularly. It’s a vital check and part of your annual review. You’re entitled to get this test at least once a year. But if your HbA1c is high or needs a little more attention, it’ll be done every three to six months. It’s really important not to skip these tests, so if you haven’t had one in over a year contact your healthcare team.

Once you know your HbA1c level, it’s important that you understand what the results mean and how to stop them from getting too high. Even a slightly raised HbA1c level makes you more at risk of serious complications, so get all the facts here and be in the know about HbA1c.

What is a HbA1c test?

The hemoglobin A1c (HbA1c) test measures the amount of blood sugar (glucose) attached to your hemoglobin. Hemoglobin is the part of your red blood cells that carries oxygen from your lungs to the rest of your body. It is an important blood test that gives a good indication of how well your diabetes is being controlled.

You can check these average blood sugar levels yourself, but you’ll have to buy a kit, whereas your healthcare professional will do it for free. It’s different from a finger-prick test, which is a snapshot of your blood sugar levels at a particular time, on a particular day.

You find out your HbA1c level by getting a blood test by a doctor or nurse. Your healthcare team will arrange this for you, but chase it up with your GP if you haven’t had one for a few months. 

Most people will have the test every three to six months. But you may need it more often if you’re planning for a baby, your treatment has recently changed, or you’re having problems managing your blood sugar levels.

And some people will need the test less often, usually later on during pregnancy. Or need a different test altogether, like with some types of anaemia. A fructosamine test can be used instead, but it’s very rare.

An HbA1c test is also used to diagnose diabetes, and to keep an eye on your levels if you’re at risk of developing diabetes (you have prediabetes).

The test is sometimes called haemoglobin A1c or just A1c.

Your HbA1c results

You should get the results quickly. The result of the HbA1c test lets your healthcare team know if they need to change your treatment or medication to help you manage your levels better. But it also tells you a number and it’s important you understand what this means. Some people find it helps to write their results down in a diary, to keep track of them and see if they can spot any trends.

And your HbA1c can change for lots of reasons, including:

• if you’re unwell
• if you’re taking other medicines, like steroids
• changes in lifestyle
• if you’re feeling very stressed or you’re depressed.

You’ll talk to your healthcare team about a target level that you need to aim for. We know this isn’t as easy as it sounds, but it’s important you do everything you can to keep in your target range. The longer your HbA1c level is even slightly high, the more you’re at risk of developing life-threatening complications.

We have lots of information and tools to help you lower your HbA1c.

What is a normal range for an HbA1c test?

If you have diabetes, an ideal HbA1c level is 48mmol/mol (6.5%) or below.

HbA1c levels and targets

But everyone’s different. So your healthcare team may give you an individual target level that takes into account your current level and when your next test is. So you can bring it down in stages and isn’t a sudden big drop.

And we’re not saying it’s easy to get to and stay at this level. We know it’s difficult, and we’re here to give you advice and information to help.

If you’re at risk of type 2 diabetes

There are different target HbA1c levels for people at risk of developing type 2 diabetes. If you’ve been told you’re at risk, your target level should be below 42mmol/mol (6%). We have lots more information for you if you’re at risk of type 2.

Type 2 diabetes remission

Remission is when a person with type 2 diabetes has healthy blood glucose (also called sugar) levels for the long-term, without taking any diabetes medications. We’re working with international experts to agree this, but our researchers used an HbA1c level of 48mmol/mol (6.5%) or less to define remission.

Type 2 diabetes is still a serious condition. It can be lifelong and get worse over time for many, but it doesn’t have to be like this for everyone. This can be life-changing. Find out more about type 2 diabetes remission.

HbA1c converter

If you’re wondering how to convert HbA1c mmol/mol to %, or vice versa, our tool can help you. 

Mmol/mol stands for millimoles per mole. A mole is a scientific unit often used to measure chemicals, and it has been the standard measurement for glucose levels since 2009. Before that, a percentage was used. That’s why measurements often have a percentage as well.

If you’re more used to the percentage system, use our converter tool below to find out your level in millimoles.

How to lower your HbA1c levels

If your levels have gone above your target since your last check, it’s understandable to be worried. Even a slightly high HbA1c level puts you more at risk of developing serious complications in your body. But knowing your numbers and what that means is an important and good first step – now you need to know how to lower them.

Lots of things can cause your HbA1c levels to change and there’s action you and your healthcare team can take to bring them down to your target level:

• Your diabetes team may need to review your medication and increase the dose or try a new one.
• Ask them about local diabetes education courses – there’s always more to learn with diabetes and a course will help you take practical steps to lower your HbA1c.
• Get more active – moving more is good for everyone, but it can specifically help to bring down your HbA1c levels.
• Get advice on balanced, healthy eating.
• Stop smoking – smoking makes it harder for blood to flow around your body. 

And if you want to hear from others who are experiencing this too, think about joining our online forum. It’s a place where you can chat to others or just read other people’s stories.

And don’t forget, get advice from your healthcare team. They’re here to help.

HbA1c test and finger-prick test – what’s the difference?

Get more information on checking your own blood sugars using a finger-prick test.

HbA1c test	Finger-prick test
Measures your average blood sugar levels over last 2 to 3 months	Snapshot of blood sugar levels at the time
Everyone with diabetes should have this test	Only people taking certain medicines need to do this test, like insulin and sulphonylureas
Usually done every 3 to 6 months	Done a number of times a day, usually ranging from twice to 10 times
Blood is taken from arm or finger	Tiny drop of blood taken from the finger
A healthcare professional should do this for you, though you can pay for a kit and do it yourself. These aren’t available on prescription.	You can do this yourself, using a testing kit
Doctors can use this test to find out how someone is managing their diabetes, to diagnose diabetes and find out if someone is at risk of type 2 diabetes	This test is mainly used for people living with diabetes

A1C: MedlinePlus

Also called: Glycohemoglobin, HbA1C, Hemoglobin A1C test

A1C is a blood test for type 2 diabetes and prediabetes. It measures your average blood glucose, or blood sugar, level over the past 3 months. Doctors may use the A1C alone or in combination with other diabetes tests to make a diagnosis. They also use the A1C to see how well you are managing your diabetes. This test is different from the blood sugar checks that people with diabetes do every day.

Your A1C test result is given in percentages. The higher the percentage, the higher your blood sugar levels have been:

• A normal A1C level is below 5. 7%
• Prediabetes is between 5.7 to 6.4%. Having prediabetes is a risk factor for getting type 2 diabetes. People with prediabetes may need retests every year.
• Type 2 diabetes is above 6.5%
• If you have diabetes, you should have the A1C test at least twice a year. The A1C goal for many people with diabetes is below 7. It may be different for you. Ask what your goal should be. If your A1C result is too high, you may need to change your diabetes care plan.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

• A1C and eAG

  (American Diabetes Association)

• A1C Test and Diabetes

  (National Institute of Diabetes and Digestive and Kidney Diseases)

  Also in Spanish

• A1C Test and Race/Ethnicity

  (National Institute of Diabetes and Digestive and Kidney Diseases)

• Hemoglobin A1C (HbA1c) Test

  (National Library of Medicine)

  Also in Spanish

• Understanding A1C

  (American Diabetes Association)

• ClinicalTrials. gov: Hemoglobin A1C

  (National Institutes of Health)

• Article: High hemoglobin glycation index is associated with increased risk of diabetes:. ..

• Article: Association between hemoglobin glycation index and non-alcoholic fatty liver disease.

• Article: The association between self-monitoring of blood glucose and HbA1c in type. ..

• A1C — see more articles

Hb-What? What does the HbA1C indicator mean?

HbA1c is a scary abbreviation of letters and numbers. A person with type 1 diabetes can experience a drop in energy from just one HbA1c value if it has a value that differs from the norm that the attending physicians have indicated. However, once you understand the importance of monitoring HbA1c and explore options for monitoring it, you will perk up and feel the power of this mysterious alphanumeric combination.

Blood glucose monitor

There are several methods for measuring blood glucose (BG). You can use one or a combination of several of them, depending on your lifestyle and the advice of your healthcare providers.

1. Finger blood sampling: measurement of the current blood glucose level at a specific point in time (single value).

2. Continuous Glucose Monitoring (CGM): An overview of daily glucose levels that allows you to track glycemic profiles.

3. Time in range (TIR): This quantity was introduced relatively recently and is used primarily by users of CGM devices. It indicates the percentage of time your BGs are in the target range (3. 9-10.0 mmol/L or 70-180 mg/dL) over a specified period.

4. HbA1c check: A picture of how well you control your diabetes over a longer period.

HbA1c is a kind of chemical “footprint” that reflects the amount of glucose in your bloodstream over the past 60-90 days (the average lifespan of red blood cells). As a general rule, people with diabetes are advised to aim for an HbA1c level of no more than 6.5% (48 mmol/mol), but your healthcare provider will set a more specific HbA1c target that is calculated specifically for you. This will help minimize the risk of developing diabetes-related complications. ¹ It is important to measure your HbA1c levels at least every three months to get a better idea of ​​your progress in diabetes control and, if necessary, adjust your treatment regimen and lifestyle for even better results.

Stop being afraid of these obscure abbreviations! 7 Steps to Get Your HbA1c Under Control

Proper doses of insulin must be administered to keep HbA1c within the target range and reduce the risk of complications. There are several different ways to administer insulin, including conventional therapy, multiple daily injections, and the most convenient method is using an insulin pump (link). Regardless of which insulin delivery method is best for you, improving blood glucose control and stabilizing HbA1c levels can greatly improve your quality of life ² and give you the opportunity to enjoy your favorite activities.

We’ve put together 7 tips to help you better control your diabetes and HbA1c.

1. Track your BG and HbA1c levels.

It’s hard to know what changes might be needed to improve your treatment if you don’t know your numbers!

2. Avoid hypoglycemia.

Selection and development of a clear algorithm for eliminating the phenomenon of hypoglycemia will allow you, in the appropriate case, not to panic and quickly take control of the situation. For example, you can always carry glucose tablets, juice or hard candy with you. The habitual algorithm will also help to avoid overcompensation, which can lead to an excessive increase in blood glucose levels.

3. Avoid episodes of hyperglycemia.

Blood glucose level can not only decrease, but also increase. An episode of hyperglycemia can occur as a result of incorrect calculation of the amount of carbohydrates consumed, the introduction of an insufficient dose of insulin, or a decrease in the effectiveness of insulin. The goal of controlling hyperglycemia is to prevent diabetic ketoacidosis and to prevent or delay the development of complications associated with high HA levels for a long time.

4. Get sick leave if you need it.

During illness, the body has to cope with increased stress. Often this leads to an increase in the level of HA. ³ Insulin pump allows you to quickly adjust the treatment regimen during illness. If you feel unwell, it is recommended to measure the level of HA more often and conduct a urine test for the content of ketone bodies.

5. Be mindful of your diet and carbohydrate intake.

Understanding how carbohydrate intake affects your blood glucose levels can help you better plan your meals and ultimately control your HbA1c levels. Review the carbohydrate content of your favorite foods and consult with your health care providers to find ways to keep your carbohydrate intake low and your enjoyment of food high.

6. Physical exercise.

Different exercises can have different effects on blood glucose levels, so keep a close eye on your performance each time you try a new activity and be prepared for a possible episode of hypoglycemia.

7. Maintain infusion sites in good condition.

When using an automatic insulin delivery system, such as an insulin pump (link), it is important to pay close attention to maintaining a healthy infusion site and to respect the expiration dates of the insulin, reservoir, and infusion set. Important recommendations include changing the infusion site regularly, checking the condition of the infusion site frequently, installing the system only in approved locations, and maintaining an adequate supply of consumables.

Conclusion

Measuring HbA1c levels is nothing to worry about. By working with your healthcare providers to develop a personalized diabetes management plan, you can master this confusing alphanumeric combination.

References

1. Diabetes.co.uk. Guide to HbA1c. https://www.diabetes.co.uk/. 2019. Available from website: https://www.diabetes.co.uk/what-is-hba1c.html. (As of March 2022)
2. Herman W, Braffett B, Kuo S, Lee J, Brandle M, Jacobson A, Prosser L, Lachin J. What are the clinical, quality-of-life, and cost consequences of 30years of excellent vs. poor glycaemic control in type 1 diabetes? J Diab Comp. 2018; 32(10):911-915.
3. Diabetes.co.uk. Stress and Blood Glucose Levels. https://www.diabetes.org.uk/. 2019. Available at: https://www.diabetes.co.uk/stress-and-blood-glucose-levels.html. (As of March 2022)

*Editor’s Note: This article is adapted and reproduced from a post published on the Medtronic Diabetes Australia page.

Clinical significance of the determination of glycated hemoglobin – an article on the topic Diagnostics (laboratory)

Clinical significance of the determination of glycated hemoglobin
Glycated hemoglobin , or glycohemoglobin (shortly designated: hemoglobin A1c , HbA1c ) – biochemical a blood indicator that reflects the average blood sugar content over a long period (up to three months ), as opposed to blood glucose measurement, which gives an idea of ​​the blood glucose level only at the time of the test.
Glycated hemoglobin reflects the percentage of blood hemoglobin that is irreversibly bound to glucose molecules. Glycated hemoglobin is formed as a result of the Maillard reaction between hemoglobin and blood glucose. An increase in blood glucose levels in diabetes mellitus significantly accelerates this reaction, which leads to an increase in the level of glycated hemoglobin in the blood. The lifetime of red blood cells (erythrocytes), which contain hemoglobin, averages 120-125 days. That is why the level of glycated hemoglobin reflects the average level of glycemia for about three months.
Glycated hemoglobin is an integral indicator of glycemia for three months. The higher the level of glycated hemoglobin, the higher was the glycemia over the past three months and, accordingly, the greater the risk of developing complications of diabetes.
A glycated hemoglobin test is commonly used to assess the quality of diabetes care over the previous three months. With a high level of glycated hemoglobin, treatment should be corrected (insulin therapy or hypoglycemic tablets) and diet therapy.
HbA1c values ​​from 4% to 5.9% are considered normal. In diabetes, HbA1c levels rise, indicating a greater risk of developing retinopathy, nephropathy, and other complications. The International Diabetes Federation recommends keeping HbA1c below 6.5%. An HbA1c value greater than 8% indicates that diabetes is not well controlled and therapy should be changed.

Glycosylated or glycated hemoglobin (HbA1c) is an indicator that reflects the level of glucose in the blood over the past 1-2-3 months. The main indications for use are: control of the course of diabetes mellitus (1 time in 3 months), control of the effectiveness of diabetes treatment, an indicator of the risk of developing complications of diabetes mellitus.
Glycosylated or glycated hemoglobin (HbA1c) is a compound of hemoglobin A and glucose that is formed in the body in a non-enzymatic way. Approximately 5-8% of the hemoglobin in erythrocytes binds stably to a glucose molecule. The process of attaching glucose to a hemoglobin molecule is a normal process, but during the life of an erythrocyte, with an increased long-term glucose content in the blood, this percentage increases. Such hemoglobin molecules are called glycosylated. There are several types of glycosylated hemoglobins (HbAIa, HbAIb, HbAIc). It is believed that hemoglobin – HbA1c (due to its quantitative predominance) has the greatest clinical significance. The concentration of glycosylated hemoglobin depends on the concentration of glucose in the blood. Considering that the lifespan of an erythrocyte is on average 120 days, the determination of the HbA1c content will reflect the average content of glucose in the blood serum for 1-2-3 months before the study.
In addition to hemoglobin, albumin, collagen, eye lens proteins, transferrin, erythrocyte membrane proteins and many other proteins and enzymes are subject to glycation, which leads to disruption of their functions and aggravation of the course of diabetes mellitus.
The determination of glycosylated hemoglobin is recognized by the World Health Organization as necessary to control the course of diabetes mellitus once every 3 months.
The determination of HbA1c allows monitoring of glucose levels between visits to the doctor. The higher the HbA1c content in the patient’s blood serum, the worse the glucose concentration was controlled.
Normalization of the level of HbA1c in the blood occurs on the 4-6th week after reaching the normal level of glucose. When monitoring the treatment of diabetes, it is recommended to maintain the level of glycated hemoglobin less than 7% and to review therapy if its content is more than 8% (according to the method for determining HbA1c with normal values ​​in the range of 4-6%).
Glycated hemoglobin is used as an indicator of the risk of complications of diabetes mellitus.
Values ​​may vary between laboratories depending on the analytical method used, so monitoring over time is best done in the same laboratory, or at least by the same method.
The test results can be falsely changed in any condition that affects the average lifespan of red blood cells. Bleeding or hemolysis causes a false decrease in the HbA1c result. Blood transfusions also distort the result. With iron deficiency anemia, a false increase in HbA1c is observed.

Preparing for diagnostics

• Explain to the patient that the study will evaluate the effectiveness of antidiabetic therapy.
• He should be warned that a blood sample must be taken for the study, and he should be told who and when will take blood from a vein.

Procedures

• After vein puncture, blood is drawn into an EDTA tube.
• Press down on the venipuncture site with a cotton ball until bleeding stops.
• If a hematoma forms at the venipuncture site, warm compresses are given.
• The patient is scheduled to repeat the study after 6-8 weeks.

Reference values

• Normally, the content of glycated hemoglobin is 4.0 – 5.2% of total hemoglobin.

Factors affecting the result of the study

• Confounding factors

Incorrect blood sampling – insufficient mixing of the blood with the anticoagulant (EDTA) in the test tube.

• Factors that increase results
• Carbamylated hemoglobin (formed in patients with uremia).
• Hydrochlorothiazide.
• Indapamide.
• Morphine.
• Propranolol.
• Factors causing a false increase

Hemoglobin F (fetal) and labile intermediates may cause a false increase in results.
Glycated hemoglobin. Analysis of glycosylated hemoglobin. Get tested for high blood sugar
Analysis Index Table
Glycated hemoglobin (HbA1c)

The price (cost of analysis) is temporarily not indicated on our website.
In connection with the update of the electronic version of the site.

Glucose interacts with proteins (including hemoglobin) with the formation of Schiff bases. Thus, any even short-term increase in the concentration of glucose in the blood leaves a kind of trace in the form of an increased content of glycosylated hemoglobin. HbA1 is made up of three components of HbA1a; HbA1b; HbA1c. HbA1c predominates quantitatively.

The HbA1c level reflects the hyperglycemia that has occurred during the lifetime of erythrocytes (up to 120 days). Erythrocytes circulating in the blood have different ages, therefore, for the average characteristics of the glucose level, they are guided by the half-life of erythrocytes – 60 days. Thus, the level of glycated hemoglobin shows what the concentration of glucose was in the previous 4-8 weeks and this is an indicator of the compensation of carbohydrate metabolism during this period. Measuring the concentration of HbA1 allows you to retrospectively assess the severity of hyperglycemia in diabetes mellitus. The effect of glycosylation does not depend on the daily rhythm of blood glucose fluctuations, on the physiological activity of the body, the nature of food, physical activity, and depends only on the magnitude and duration of hyperglycemia. In diabetic patients with persistent hyperglycemia, the concentration of HbA1c increases significantly. Treatment of diabetes is carried out with drugs that lower blood glucose for only a limited period of time, so it is very important to choose such treatment regimens that would achieve stable normalization of glycemia. The value of the study of glycosylated hemoglobin in diabetes mellitus lies in the fact that HbA1c characterizes a certain average level of glucose in the blood over a long period of time, which is commensurate with the half-life of the hemoglobin molecule. That is, glycosylated hemoglobin characterizes the degree of compensation for diabetes mellitus over the past 1-2 months. The better the diabetes is compensated, the lower the risk of developing such complications of diabetes as eye damage – retinopathy, kidney damage – nephropathy, damage to peripheral nerves and blood vessels leading to gangrene. Thus, the strategic goal of the treatment of diabetes mellitus is to ensure the constant maintenance of glucose within the normal range. Measurement of sugar in capillary blood allows you to assess the current level of glucose, the determination of HbA1c gives an integrated view of the level of glycemia.