The level of CRP increases when there's inflammation in the body. A simple blood test can check your C-reactive protein level. A high-sensitivity C-reactive protein hs-CRP test is more sensitive than a standard C-reactive protein test.

That means the high-sensitivity test can find smaller increases in C-reactive protein than a standard test can. The hs-CRP test can help show the risk of getting coronary artery disease. In coronary artery disease, the arteries of the heart narrow.

Narrowed arteries can lead to a heart attack. A high level of hs-CRP in the blood has been linked to an increased risk of heart attacks. Also, people who have had a heart attack are more likely to have another heart attack if they have a high hs-CRP level.

But their risk goes down when their hs-CRP level is in the typical range. An hs-CRP test isn't for everyone. The test doesn't show the cause of inflammation. So it's possible to have a high hs-CRP level without it affecting the heart. This is known as intermediate risk. A health care provider can determine your risk using tests that look at your lifestyle choices, family history and overall health.

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Hard exercise, such as intense weight training or a long run, can cause a sudden jump in the C-reactive protein level. Your health care provider might ask you to avoid such activities before the test. Some medicines can affect CRP level. Tell your care provider about the medicines you take, including those you bought without a prescription.

If your blood sample will be used for other tests, you may need to avoid food or drink for a period before the test. For example, if you're having an hs-CRP test to check for heart disease, you might have a cholesterol test, which requires fasting, at the same time.

To take a sample of your blood, a health care provider places a needle into a vein in your arm, usually at the bend of the elbow. The blood sample goes to a lab for analysis. You can return to your usual activities right away. It can take a few days to get results.

Your health care provider can explain what the test results mean. Range values vary depending on the lab doing the test. Diabetes develops over time, so even with variations in test results, health care professionals can tell when overall blood glucose levels are becoming too high.

When repeated, the A1C test result can be slightly higher or lower than the first measurement. This means, for example, an A1C reported as 6. Health care professionals can visit ngsp. org to find information about the precision of the A1C test used by their lab.

Your health care professional may use the A1C test to set your treatment goals, modify therapy, and monitor your diabetes management. Experts recommend that people with diabetes have an A1C test at least twice a year.

People will have different A1C targets, depending on their diabetes history and their general health. You should discuss your A1C target with your health care professional. Studies have shown that some people with diabetes can reduce the risk of diabetes complications by keeping A1C levels below 7 percent.

Managing blood glucose early in the course of diabetes may provide benefits for many years to come. However, an A1C level that is safe for one person may not be safe for another.

For example, keeping an A1C level below 7 percent may not be safe if it leads to problems with hypoglycemia , also called low blood glucose. Less strict blood glucose control, or an A1C between 7 and 8 percent—or even higher in some circumstances—may be appropriate in people who have. Estimated average glucose eAG is calculated from your A1C.

Some laboratories report eAG with A1C test results. The eAG number helps you relate your A1C to daily glucose monitoring levels.

Even though A1C results represent a long-term average, blood glucose levels within the past 30 days have a greater effect on the A1C reading than those in previous months. The National Institute of Diabetes and Digestive and Kidney Diseases NIDDK and other components of the National Institutes of Health NIH conduct and support research into many diseases and conditions.

Clinical trials are part of clinical research and at the heart of all medical advances. Clinical trials look at new ways to prevent, detect, or treat disease.

Scientists are conducting research to learn more about diabetes, including studies about A1C. For example. Researchers also use clinical trials to look at other aspects of care, such as improving the quality of life for people with chronic illnesses.

Find out if clinical trials are right for you. Clinical trials that are currently open and are recruiting can be viewed at www. This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases NIDDK , part of the National Institutes of Health.

NIDDK translates and disseminates research findings to increase knowledge and understanding about health and disease among patients, health professionals, and the public.

Content produced by NIDDK is carefully reviewed by NIDDK scientists and other experts. English English Español. Why should a person get the A1C test? How is the A1C test used to diagnose type 2 diabetes and prediabetes?

Is the A1C test used during pregnancy? Can other blood glucose tests be used to diagnose type 2 diabetes and prediabetes? Can the A1C test result in a different diagnosis than the blood glucose tests?

Why do diabetes blood test results vary? As we mentioned, your A1C value is an average of the glucose in your blood during a two or three month period in which your red blood cells are alive. Because A1C represents sugar levels over an extended amount of time, your doctor can use this to get a general idea of your blood sugar control over time.

It is instead a measure of the percent of hemoglobin that has glucose bound to it. While A1C can be a helpful tool to estimate how your blood sugar has been on average, there are some outside factors that may skew the accuracy of your A1C reading , such as certain medications or health conditions.

Is your A1C high but you're not diabetic? Discover 7 reasons your A1C might be high without diabetes and get tips to lower your A1C levels here.

Like A1C, your estimated average glucose or eAG measures the average levels of your blood sugar over a few months. However, this is just an estimate derived from A1C, and not a precise measurement. You may have had your doctor explain your A1C levels in terms of estimated average glucose, or eAG.

Just like with A1C, regularly checking your eAG may give you a more accurate representation of your blood sugar response over time. However, eAG may not always correspond accurately to fasting glucose FPG levels.

In a study published in the journal Healthcare , researchers found that the proportion of subjects with a higher value of FPG than eAG was If your A1C or eAG is out of the normal range, you may want to speak with a doctor about what factors may be causing your elevated levels and how they may affect your well-being.

You may also want to ask your doctor about the need for testing your fasting glucose FPG levels. Keep in mind that blood glucose is measured in different ways depending on where you live.

To calculate your A1C value, all you need to do is apply your average blood glucose measurement to one of the following formulas:. Not everyone loves crunching numbers. Instead, try calculating an estimation of your A1C value using our handy A1C calculator.

Once you have an estimate of your A1C, check whether your levels are outside of the normal range by comparing your result to the ranges used by both the American Diabetes Association ADA and the CDC as shown below. If your estimated range falls anywhere above 5.

There are a number of lifestyle changes that may be beneficial as you work to lower your levels over time. One way to detect imbalances and fluctuations in glucose to see its impact on your overall health is by using a tool such as a continuous glucose monitor.

If your A1C is out of the ideal range, your doctor may also help you set an A1C goal to aim for. Most CGMs can provide you with a 30, 60, or day average of your glucose readings over a chosen period.

Using the calculator or conversion formulas that we shared earlier in the article, you can calculate an estimation of your A1C from your blood glucose data collected from a CGM. However, be aware that your average glucose readings from a CGM may also require additional calibration or verification with a reference fasting glucose lab value for more accurate baseline or average glucose depiction.

Some apps, such as the Nutrisense app , will automatically provide you with your average glucose calculation based on your CGM readings. If you already know your eAG level from a doctor's visit or another blood test, you can calculate your A1C from your average blood glucose reading by using the calculator or formulas above.

Remember, however, that this measurement is an estimation and if you find that your value is outside of the normal range , you may want to speak to your doctor to learn more.

Kidney failure and liver disease can also affect A1C results. In these cases, your provider may recommend different tests to diagnose diabetes and prediabetes. The information on this site should not be used as a substitute for professional medical care or advice.

Contact a health care provider if you have questions about your health. Hemoglobin A1C HbA1c Test. What is a hemoglobin A1C HbA1C test? An A1C test can show your average glucose level for the past three months because: Glucose sticks to hemoglobin for as long as the red blood cells are alive.

Red blood cells live about three months. Other names: HbA1C, A1C, glycohemoglobin, glycated hemoglobin, glycosylated hemoglobin.

What is it used for? An A1C test may be used to screen fo r or diagnose: Type 2 diabetes. With type 2 diabetes your blood glucose gets too high because your body doesn't make enough insulin to move blood sugar from your bloodstream into your cells, or because your cells stop responding to insulin.

Prediabetes means that your blood glucose levels are higher than normal, but not high enough to diagnosed as diabetes. Lifestyle changes, such as healthy eating and exercise , may help delay or prevent prediabetes from becoming type 2 diabetes.

Why do I need an HbA1C test? The Centers for Disease Control CDC recommends A1C testing for diabetes and prediabetes if: You are over age If your results are normal, you should repeat the test every 3 years.

If your results show you have prediabetes, you will usually need to be tested every 1 to 2 years. Ask your provider how often to get tested and what you can do to reduce your risk of developing diabetes. If your results show you have diabetes, you should get an A1C test at least twice a year to monitor your condition and treatment.

You are under 45 and are more likely to develop diabetes because you: Have prediabetes. Are overweight or have obesity. Have a parent or sibling with type 2 diabetes. Have high blood pressure or high cholesterol levels. Have heart disease or have had a stroke.

Are physically active less than 3 times a week. Have had gestational diabetes diabetes during pregnancy or given birth to a baby over 9 pounds. Are African American, Hispanic or Latino, American Indian, or an Alaska Native person. Some Pacific Islander and Asian American people also have a higher risk of developing diabetes.

Have polycystic ovarian syndrome PCOS. You may also need an A1C test if you have symptoms of diabetes, such as: Feeling very thirsty Urinating peeing a lot Losing weight without trying Feeling very hungry Blurred vision Numb or tingling hands or feet Fatigue Dry skin Sores that heal slowly Having more infections than usual.

What happens during an A1C test? The best defense is to brush your teeth twice a day and visit your dentist twice a year. Managing blood sugar to keep your A1C in your target range can prevent diabetic complications. If your A1C is high, work with your healthcare team to develop a plan.

Blood-sugar lowering strategies primarily include self-management tools and making healthy choices. Research shows a direct link between more frequent blood sugar testing and a lower A1C. At-home monitoring can be done with either a glucometer or a continuous glucose monitoring system CGMS.

Talk to your healthcare provider about how often you should test your blood sugar. In addition, keeping a blood sugar log can provide valuable information to you and your health team. This can help determine what if any changes to make to your treatment plan. Diet has a huge impact on your blood sugar.

In particular, carbohydrates like bread, rice, potatoes, and sweets raise your blood sugar. During digestion, the body breaks carbohydrates down into glucose.

One way to find out how certain foods affect your blood sugar is to test two hours after eating. Keeping a food journal along with blood sugar logs helps identify high blood sugar patterns. This can help you learn to manage your glucose levels better and lower your A1C.

Talk to your healthcare team if you are unsure what you should eat to manage your blood sugar. A dietitian or certified diabetes educator can help you learn how to balance meals for lower blood sugar. Managing stress is crucial to staying healthy in general and can particularly help people with diabetes.

Studies have shown that acute stress raises blood sugar levels by spurring glucose production and hindering insulin sensitivity.

Better control of stress can positively impact blood sugar levels. Some stress relief techniques include:. Exercise helps to lower glucose levels by improving insulin sensitivity. Insulin is a hormone that helps glucose from the blood enter your muscles and organs.

Research shows moderate exercise improves insulin sensitivity for up to 24 hours. When you exercise, your muscles use glucose for energy.

This lowers glucose levels in the blood. Studies show long-term regular physical activity has a positive impact on A1C levels. Exercise also helps to spur weight loss, reduce stress, and improve cardiovascular health. The more exercise, the greater A1C reduction.

Most people with diabetes should aim for at least minutes of moderate-intensity exercise each week. People who take insulin or other medications that lower blood sugar should monitor their blood sugar more closely during and after exercise to prevent hypoglycemia.

If you cannot lower your A1C through lifestyle changes, medication may be warranted. Type 1 diabetics require insulin. Your endocrinologist may make adjustments to your basal and bolus rates. Bring up-to-date glucose logs and food journals to your appointment. This data can help your doctor or diabetes nurse dial in the right insulin-to-carb ratio and basal rates.

If that doesn't bring your A1C down, other medications can be added to help improve control. Prescription medication for type 2 diabetes work in a few different ways.

Some help your body make more insulin, and others help your body use the insulin it makes. Some people with type 2 diabetes use insulin to manage their blood sugar. Remember to take your medication as prescribed and check with your healthcare team if you have any questions.

The A1C test measures the average blood glucose level over a three-month span. It is used to diagnose diabetes and monitor diabetic treatment. A high A1C level increases your risk of diabetic complications.

Over time, high blood sugars cause cardiac disease, diabetic retinopathy, kidney failure, neuropathy, and gum disease. For people with diabetes, getting regular bloodwork can catch a high A1C early.

At-home blood glucose monitoring, a low-carbohydrate diet, and exercise can help lower your A1C. If lifestyle changes do not help, your doctor may prescribe medications or change your doses.

Talk to your healthcare team about any issues or questions you have. A high A1C is a sign that your diabetes care plan isn't working. Blood sugar management depends primarily on self-care: counting carbs, testing your blood sugar, and making healthy choices. Burnout is common and nothing to be ashamed of.

The important thing is to get back on track. If you are struggling with diabetes self-management, talk to your healthcare team. Be honest about your challenges so they can help you set healthy goals. Resources like a certified diabetes educator, dietitian, or the online diabetes community can be a big help.

Living with a chronic illness like diabetes can be hard. Finding support from other diabetics can help you know you aren't alone. It depends. You do not need to fast for an A1C test. However, you may need to fast for other tests ordered along with an A1C, such as fasting glucose and cholesterol tests.

A1C tests are typically pretty accurate, though there is a slight margin of error. An A1C can be off by as much as 0. That means a result of 6. Several factors can falsely increase or decrease your A1C result, including:.

The A1C test should not be used to diagnose type 1 diabetes, gestational diabetes, or cystic fibrosis-related diabetes. ElSayed NA, Aleppo G, Aroda VR, et al. Classification and diagnosis of diabetes: Standards of care in diabetes [published correction appears in Diabetes Care.

Diabetes Care. National Institute of Diabetes and Digestive and Kidney Disease. Centers for Disease Control and Prevention. All about your A1C.

Huang ES, Liu JY, Moffet HH, John PM, Karter AJ. Glycemic control, complications, and death in older diabetic patients: the diabetes and aging study.

National Institute of Diabetes and Digestive and Kidney Diseases. Diabetes, heart disease, and stroke. Diabetes and your heart. Before confirming a diagnosis of diabetes, your doctor should repeat the test that was abnormal on a different day. Some people may get false results if they have kidney failure , liver disease , or severe anemia.

Ethnicity can also influence the test. People of African, Mediterranean, or Southeast Asian descent may have a less common type of hemoglobin that can interfere with some A1C tests. A1C can also be affected if red cell survival is decreased.

Adults over the age of 45 should take an A1C test to get a baseline reading. High A1C levels are indicative of uncontrolled diabetes, which has been linked to an increased risk of the following conditions:.

Starting an exercise program can help. Prediabetes can progress to diabetes. You may also need to make other lifestyle changes and monitor your daily blood glucose more closely. Talk with your doctor about the best treatment plan for you. The A1C test measures the amount of hemoglobin in the blood that has glucose attached to it.

The test provides an average of your blood sugar readings for the past 3 months. People with diabetes should take an A1C test at least twice a year and more frequently in some cases. Read this article in Spanish. Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available.

VIEW ALL HISTORY. In addition to medications like insulin injections, there are also complementary and alternative therapies for managing diabetes.

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When managing blood glucose levels is challenging, a person needs this test more frequently. Anyone who develops any of the symptoms above or notices other changes in their health should inform a doctor.

A doctor orders an A1C test to check whether someone has prediabetes or type 1 or 2 diabetes. Doctors also use this test to monitor blood glucose levels in people with diabetes to check how well their treatment plan is working. A1C test results are usually a percentage but may come as an eAG measurement.

Target A1C levels vary from person to person, depending on age, overall health, and other factors. Having high A1C levels may indicate a person has diabetes or a high risk of related complications.

In this case, a doctor will work with the individual to adjust the treatment approach. Diabetes can happen when healthy sugar levels are not maintained. Learn what levels should be and the symptoms of high and low blood sugar. Insulin is a hormone that plays a central role in controlling blood sugar levels in the body.

People with diabetes produce either insufficient or…. Diabetes is a condition where the body does not produce insulin or does not use it efficiently.

There are different types of diabetes. Learn more here. Researchers say gastric bypass surgery is more effective than gastric sleeve procedures in helping people go into remission from type 2 diabetes.

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Medical News Today. Health Conditions Health Products Discover Tools Connect. A1C chart and understanding A1C levels. Medically reviewed by Kelly Wood, MD — By Heather Grey — Updated on November 22, What is an A1C chart?

How the A1C test works. Normal levels. A1C levels by age. Age group All respondents Men Women 20—39 years 4. How often to get the A1C test.

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Overview The A1C test is a common blood test used to diagnose type 1 and type 2 diabetes. More Information Diabetes Hyperglycemia in diabetes Prediabetes Type 1 diabetes Type 1 diabetes in children Type 2 diabetes Type 2 diabetes in children Show more related information.

Request an appointment. Thank you for subscribing! Sorry something went wrong with your subscription Please, try again in a couple of minutes Retry. By Mayo Clinic Staff. Show references American Diabetes Association, Professional Practice Committee. Standards of Medical Care in Diabetes — Diabetes Care.

Type 2 diabetes mellitus adult. Mayo Clinic; National Institute of Diabetes and Digestive and Kidney Diseases.

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The more exercise, the greater A1C reduction. Most people with diabetes should aim for at least minutes of moderate-intensity exercise each week.

People who take insulin or other medications that lower blood sugar should monitor their blood sugar more closely during and after exercise to prevent hypoglycemia.

If you cannot lower your A1C through lifestyle changes, medication may be warranted. Type 1 diabetics require insulin. Your endocrinologist may make adjustments to your basal and bolus rates. Bring up-to-date glucose logs and food journals to your appointment.

This data can help your doctor or diabetes nurse dial in the right insulin-to-carb ratio and basal rates. If that doesn't bring your A1C down, other medications can be added to help improve control.

Prescription medication for type 2 diabetes work in a few different ways. Some help your body make more insulin, and others help your body use the insulin it makes. Some people with type 2 diabetes use insulin to manage their blood sugar.

Remember to take your medication as prescribed and check with your healthcare team if you have any questions.

The A1C test measures the average blood glucose level over a three-month span. It is used to diagnose diabetes and monitor diabetic treatment. A high A1C level increases your risk of diabetic complications.

Over time, high blood sugars cause cardiac disease, diabetic retinopathy, kidney failure, neuropathy, and gum disease. For people with diabetes, getting regular bloodwork can catch a high A1C early.

At-home blood glucose monitoring, a low-carbohydrate diet, and exercise can help lower your A1C. If lifestyle changes do not help, your doctor may prescribe medications or change your doses. Talk to your healthcare team about any issues or questions you have.

A high A1C is a sign that your diabetes care plan isn't working. Blood sugar management depends primarily on self-care: counting carbs, testing your blood sugar, and making healthy choices.

Burnout is common and nothing to be ashamed of. The important thing is to get back on track. If you are struggling with diabetes self-management, talk to your healthcare team. Be honest about your challenges so they can help you set healthy goals. Resources like a certified diabetes educator, dietitian, or the online diabetes community can be a big help.

Living with a chronic illness like diabetes can be hard. Finding support from other diabetics can help you know you aren't alone. It depends. You do not need to fast for an A1C test.

However, you may need to fast for other tests ordered along with an A1C, such as fasting glucose and cholesterol tests. A1C tests are typically pretty accurate, though there is a slight margin of error.

An A1C can be off by as much as 0. That means a result of 6. Several factors can falsely increase or decrease your A1C result, including:.

The A1C test should not be used to diagnose type 1 diabetes, gestational diabetes, or cystic fibrosis-related diabetes. ElSayed NA, Aleppo G, Aroda VR, et al.

Classification and diagnosis of diabetes: Standards of care in diabetes [published correction appears in Diabetes Care. Diabetes Care. National Institute of Diabetes and Digestive and Kidney Disease. Centers for Disease Control and Prevention. All about your A1C.

Huang ES, Liu JY, Moffet HH, John PM, Karter AJ. Glycemic control, complications, and death in older diabetic patients: the diabetes and aging study. National Institute of Diabetes and Digestive and Kidney Diseases.

Diabetes, heart disease, and stroke. Diabetes and your heart. Tun NN, Arunagirinathan G, Munshi SK, Pappachan JM. Diabetes mellitus and stroke: A clinical update. World J Diabetes. Diabetic eye disease. El Sayed NA, Aleppo G, Aroda VR, et al. Retinopathy, neuropathy, and foot care: Standards of care in diabetes Bain SC, Klufas MA, Ho A, Matthews DR.

Worsening of diabetic retinopathy with rapid improvement in systemic glucose control: A review. Diabetes Obes Metab. Diabetes and nerve damage.

Diabetic kidney disease. Chronic kidney disease and risk management: Standards of care in diabetes Helgeson VS, Honcharuk E, Becker D, Escobar O, Siminerio L.

A focus on blood glucose monitoring: relation to glycemic control and determinants of frequency. Pediatr Diabetes. Wright EE Jr, Kerr MSD, Reyes IJ, Nabutovsky Y, Miller E. Use of Flash Continuous Glucose Monitoring is associated with A1C reduction in people with type 2 diabetes treated with basal insulin or noninsulin therapy.

Diabetes Spectr. Hilliard ME, Yi-Frazier JP, Hessler D, Butler AM, Anderson BJ, Jaser S. Stress and A1c among people with diabetes across the lifespan.

Curr Diab Rep. American Diabetes Association. Blood sugar and exercise. Najafipour F, Mobasseri M, Yavari A, et al. Effect of regular exercise training on changes in HbA1c, BMI and VO2max among patients with type 2 diabetes mellitus: an 8-year trial.

BMJ Open Diabetes Res Care. Facilitating positive health behaviors and well-being to improve health outcomes: Standards of care in diabetes Penttilä I, Penttilä K, Holm P, Laitinen H, Ranta P, Törrönen J, Rauramaa R. A1C tests are less likely to be affected by short-term changes than FPG or OGTT tests.

The following chart shows how multiple blood glucose measurements over 4 days compare with an A1C measurement. The straight black line shows an A1C measurement of 7. The blue line shows an example of how blood glucose test results might look from self-monitoring four times a day over a 4-day period.

Conditions that change the life span of red blood cells, such as recent blood loss, sickle cell disease , erythropoietin treatment, hemodialysis , or transfusion, can change A1C levels.

A falsely high A1C result can occur in people who are very low in iron; for example, those with iron-deficiency anemia.

Other causes of false A1C results include kidney failure or liver disease. People in these groups may have a different type of hemoglobin, known as a hemoglobin variant, which can interfere with some A1C tests.

Most people with a hemoglobin variant have no symptoms and may not know that they carry this type of hemoglobin.

Not all A1C tests are unreliable for people with a hemoglobin variant. People with false results from one type of A1C test may need a different type of A1C test to measure their average blood glucose level.

The NGSP provides information for health care professionals about which A1C tests are appropriate to use for specific hemoglobin variants. Read about diabetes blood tests for people of African, Mediterranean, or Southeast Asian descent.

Even when the same blood sample is repeatedly measured in the same lab, the results may vary because of small changes in temperature, equipment, or sample handling. These factors tend to affect glucose measurements—fasting and OGTT—more than the A1C test. Health care professionals understand these variations and repeat lab tests for confirmation.

Diabetes develops over time, so even with variations in test results, health care professionals can tell when overall blood glucose levels are becoming too high. When repeated, the A1C test result can be slightly higher or lower than the first measurement.

This means, for example, an A1C reported as 6. Health care professionals can visit ngsp. org to find information about the precision of the A1C test used by their lab.

Your health care professional may use the A1C test to set your treatment goals, modify therapy, and monitor your diabetes management.

Experts recommend that people with diabetes have an A1C test at least twice a year. People will have different A1C targets, depending on their diabetes history and their general health. You should discuss your A1C target with your health care professional.

Studies have shown that some people with diabetes can reduce the risk of diabetes complications by keeping A1C levels below 7 percent. Managing blood glucose early in the course of diabetes may provide benefits for many years to come.

However, an A1C level that is safe for one person may not be safe for another. For example, keeping an A1C level below 7 percent may not be safe if it leads to problems with hypoglycemia , also called low blood glucose.

Less strict blood glucose control, or an A1C between 7 and 8 percent—or even higher in some circumstances—may be appropriate in people who have.

Estimated average glucose eAG is calculated from your A1C. Some laboratories report eAG with A1C test results. The eAG number helps you relate your A1C to daily glucose monitoring levels.

Even though A1C results represent a long-term average, blood glucose levels within the past 30 days have a greater effect on the A1C reading than those in previous months. The National Institute of Diabetes and Digestive and Kidney Diseases NIDDK and other components of the National Institutes of Health NIH conduct and support research into many diseases and conditions.

Clinical trials are part of clinical research and at the heart of all medical advances. An A1C value differs from the glucose insights you would get from a glucometer or continuous glucose monitor CGM.

These tools can be helpful for recognizing instances of hypoglycemia low blood sugar as they occur, or hyperglycemia high blood sugar after eating a meal.

CGMs can also be particularly helpful in tracking glycemic variability , or how your glucose fluctuates in real time. A1C does not measure glycemic variability.

While many routine blood tests measure things like your lipid levels or red and white blood cell count, an A1C test will usually need to be specifically requested by you and your doctor. This test is known as an HbA1C test , and unlike other types of blood tests, fasting is not required beforehand.

A1C is a measurement of glycated hemoglobin , and is reported as a percentage of your average blood sugar level. For more information on what these values signify, read our article on normal blood sugar levels. As we mentioned, your A1C value is an average of the glucose in your blood during a two or three month period in which your red blood cells are alive.

Because A1C represents sugar levels over an extended amount of time, your doctor can use this to get a general idea of your blood sugar control over time. It is instead a measure of the percent of hemoglobin that has glucose bound to it.

While A1C can be a helpful tool to estimate how your blood sugar has been on average, there are some outside factors that may skew the accuracy of your A1C reading , such as certain medications or health conditions. Is your A1C high but you're not diabetic? Discover 7 reasons your A1C might be high without diabetes and get tips to lower your A1C levels here.

Like A1C, your estimated average glucose or eAG measures the average levels of your blood sugar over a few months. However, this is just an estimate derived from A1C, and not a precise measurement. You may have had your doctor explain your A1C levels in terms of estimated average glucose, or eAG.

Just like with A1C, regularly checking your eAG may give you a more accurate representation of your blood sugar response over time.

However, eAG may not always correspond accurately to fasting glucose FPG levels. In a study published in the journal Healthcare , researchers found that the proportion of subjects with a higher value of FPG than eAG was If your A1C or eAG is out of the normal range, you may want to speak with a doctor about what factors may be causing your elevated levels and how they may affect your well-being.

You may also want to ask your doctor about the need for testing your fasting glucose FPG levels. Keep in mind that blood glucose is measured in different ways depending on where you live. To calculate your A1C value, all you need to do is apply your average blood glucose measurement to one of the following formulas:.

Not everyone loves crunching numbers. Instead, try calculating an estimation of your A1C value using our handy A1C calculator. Once you have an estimate of your A1C, check whether your levels are outside of the normal range by comparing your result to the ranges used by both the American Diabetes Association ADA and the CDC as shown below.

If your estimated range falls anywhere above 5. There are a number of lifestyle changes that may be beneficial as you work to lower your levels over time.