What is a healthy A1C level. How does A1C testing work. Why is A1C important for diabetes diagnosis and management. Who should get an A1C test and how often. How to interpret A1C results. What factors can affect A1C levels.

What is A1C and Why is it Important?

A1C, also known as hemoglobin A1C or HbA1c, is a crucial blood test that provides invaluable information about blood sugar control over time. But what exactly does it measure? The A1C test determines the percentage of hemoglobin proteins in red blood cells that have become glycated (coated with sugar) over the past 2-3 months. This gives an average picture of blood glucose levels during that period.

The importance of A1C cannot be overstated when it comes to diabetes management and prevention. It serves as a key diagnostic tool for prediabetes and diabetes, while also helping healthcare providers and patients monitor long-term blood sugar control. Elevated A1C levels are strongly associated with an increased risk of diabetes complications, making it essential to achieve and maintain target A1C goals.

How does A1C differ from daily blood glucose monitoring?

While daily blood glucose checks provide a snapshot of sugar levels at a specific moment, A1C offers a broader view of glucose control over time. This makes it an indispensable complement to regular self-monitoring for individuals managing diabetes.

Who Should Get an A1C Test and How Often?

A1C testing is recommended for various groups of people, depending on their risk factors and current health status. Here are the key guidelines:

• Adults over 45: A baseline A1C test is recommended
• Adults under 45 who are overweight and have additional risk factors for prediabetes or type 2 diabetes
• Individuals with prediabetes: Testing every 1-2 years
• People diagnosed with diabetes: At least twice a year, more frequently if medications change or other health conditions are present

For those without diabetes but with risk factors, repeating the A1C test every 3 years is advised. If prediabetes is detected, it’s crucial to work with a healthcare provider to implement lifestyle changes and reduce the risk of progressing to type 2 diabetes.

Can A1C be used to diagnose gestational diabetes?

While A1C is not typically used to diagnose gestational diabetes, women who have had gestational diabetes in the past should have their A1C levels checked regularly, as they are at increased risk for developing type 2 diabetes later in life.

Interpreting A1C Results: What Do the Numbers Mean?

Understanding A1C results is crucial for both diagnosis and ongoing diabetes management. The American Diabetes Association provides the following guidelines for interpreting A1C levels:

• Normal: Below 5.7%
• Prediabetes: 5.7% to 6.4%
• Diabetes: 6.5% or above

It’s important to note that within the prediabetes range, higher A1C levels indicate a greater risk of progressing to type 2 diabetes. For individuals managing diabetes, A1C goals are often personalized based on factors such as age, overall health, and risk of hypoglycemia.

How does A1C relate to average blood glucose levels?

A1C results can be translated into estimated average glucose (eAG) values, which correspond to the mg/dL readings seen on home glucose meters. This conversion helps patients better understand the relationship between their A1C and daily glucose measurements:

Factors That Can Affect A1C Results

While A1C is generally a reliable indicator of blood glucose control, several factors can influence the results. Being aware of these potential confounders is essential for accurate interpretation:

• Kidney failure, liver disease, or severe anemia
• Hemoglobin variants more common in people of African, Mediterranean, or Southeast Asian descent
• Certain blood disorders (e.g., sickle cell anemia, thalassemia)
• Some medications, including opioids and certain HIV treatments
• Recent blood loss or transfusions
• Pregnancy, particularly in early or late stages

If any of these factors apply, it’s crucial to discuss them with a healthcare provider. Additional testing may be necessary to ensure accurate assessment of blood glucose control.

Are there alternatives to A1C testing for people with hemoglobin variants?

For individuals with hemoglobin variants that may affect A1C results, alternative tests such as fructosamine or glycated albumin may be used to assess blood glucose control over shorter periods.

Setting and Achieving A1C Goals in Diabetes Management

Establishing appropriate A1C targets is a collaborative process between patients and their healthcare providers. While the general goal for most people with diabetes is an A1C of 7% or less, individual targets may vary based on several factors:

• Age
• Duration of diabetes
• Presence of other medical conditions
• Risk of hypoglycemia
• Individual life expectancy

Younger individuals may have lower A1C goals to reduce the long-term risk of complications, while older adults or those with a history of severe hypoglycemia may have slightly higher targets. Regular discussions with healthcare providers are essential to adjust goals as circumstances change.

How can lifestyle changes impact A1C levels?

Implementing healthy lifestyle habits can significantly improve A1C levels. Key strategies include:
– Maintaining a balanced diet rich in whole foods
– Engaging in regular physical activity
– Managing stress effectively
– Adhering to prescribed medications
– Monitoring blood glucose regularly

The Role of A1C in Comprehensive Diabetes Care

While A1C is a powerful tool in diabetes management, it’s important to recognize its limitations. A1C provides an average of blood glucose levels but doesn’t capture day-to-day fluctuations or patterns. This is why combining A1C testing with regular blood glucose monitoring is crucial for optimal diabetes management.

Patients may have the same A1C level but very different daily glucose profiles. Some may maintain steady levels throughout the day, while others experience significant highs and lows. Understanding these patterns is essential for fine-tuning treatment plans and reducing the risk of complications.

How often should blood glucose be checked in addition to A1C testing?

The frequency of blood glucose monitoring varies depending on the individual’s diabetes management plan. Those using insulin may need to check several times a day, while others might test less frequently. Working with a healthcare provider to establish an appropriate monitoring schedule is key.

Advances in A1C Testing and Future Directions

As diabetes care continues to evolve, so do the technologies and methodologies surrounding A1C testing. Recent advancements include:

• Point-of-care A1C testing, allowing for rapid results during office visits
• Improved accuracy in A1C assays, reducing variability between labs
• Integration of A1C data with continuous glucose monitoring (CGM) systems for more comprehensive analysis

Future developments may focus on personalized A1C targets based on genetic factors and individual risk profiles. Additionally, research is ongoing to explore novel biomarkers that could complement or potentially replace A1C in certain situations.

How might artificial intelligence impact A1C interpretation and diabetes management?

Artificial intelligence and machine learning algorithms are being developed to analyze A1C results in conjunction with other health data. These tools could potentially provide more nuanced interpretations and personalized treatment recommendations, enhancing diabetes care in the future.

Empowering Patients: Making the Most of A1C Information

Understanding A1C results empowers patients to take an active role in their diabetes management. Here are some strategies for making the most of A1C information:

1. Keep a log of A1C results over time to track progress
2. Discuss A1C goals and any concerns with healthcare providers
3. Use A1C results as motivation for maintaining or improving diabetes self-care habits
4. Understand the relationship between A1C and daily blood glucose readings
5. Seek diabetes education and support to develop strategies for achieving A1C goals

By actively engaging with A1C data and working closely with healthcare teams, individuals with diabetes can optimize their management plans and reduce the risk of long-term complications.

How can patients prepare for A1C discussions with their healthcare providers?

To make the most of A1C-related appointments, patients can:
– Bring a record of recent A1C results and daily glucose readings
– Prepare questions about their current management plan
– Be ready to discuss any challenges or successes in diabetes self-care
– Consider bringing a trusted family member or friend for support and to help remember important information

All About Your A1C

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What has your blood sugar been up to lately? Get an A1C test to find out your average levels—important to know if you’re at risk for prediabetes or type 2 diabetes, or if you’re managing diabetes.

The A1C test—also known as the hemoglobin A1C or HbA1c test—is a simple blood test that measures your average blood sugar levels over the past 3 months. It’s one of the commonly used tests to diagnose prediabetes and diabetes, and is also the main test to help you and your health care team manage your diabetes. Higher A1C levels are linked to diabetes complications, so reaching and maintaining your individual A1C goal is really important if you have diabetes.

What Does the A1C Test Measure?

When sugar enters your bloodstream, it attaches to hemoglobin, a protein in your red blood cells. Everybody has some sugar attached to their hemoglobin, but people with higher blood sugar levels have more. The A1C test measures the percentage of your red blood cells that have sugar-coated hemoglobin.

Who Should Get an A1C Test, and When?

Testing for diabetes or prediabetes:
Get a baseline A1C test if you’re an adult over age 45—or if you’re under 45, are overweight, and have one or more risk factors for prediabetes or type 2 diabetes:

• If your result is normal but you’re over 45, have risk factors, or have ever had gestational diabetes, repeat the A1C test every 3 years.
• If your result shows you have prediabetes, talk to your doctor about taking steps now to improve your health and lower your risk for type 2 diabetes. Repeat the A1C test as often as your doctor recommends, usually every 1 to 2 years.
• If you don’t have symptoms but your result shows you have prediabetes or diabetes, get a second test on a different day to confirm the result.
• If your test shows you have diabetes, ask your doctor to refer you to diabetes self-management education and support services so you can have the best start in managing your diabetes.

Managing diabetes:
If you have diabetes, get an A1C test at least twice a year, more often if your medicine changes or if you have other health conditions. Talk to your doctor about how often is right for you.

How to Prepare for Your A1C Test

The test is done in a doctor’s office or a lab using a sample of blood from a finger stick or from your arm. You don’t need to do anything special to prepare for your A1C test. However, ask your doctor if other tests will be done at the same time and if you need to prepare for them.

Your A1C Result

Diagnosing Prediabetes or Diabetes

A normal A1C level is below 5.7%, a level of 5. 7% to 6.4% indicates prediabetes, and a level of 6.5% or more indicates diabetes. Within the 5.7% to 6.4% prediabetes range, the higher your A1C, the greater your risk is for developing type 2 diabetes.

Managing Diabetes
Your A1C result can also be reported as estimated average glucose (eAG), the same numbers (mg/dL) you’re used to seeing on your blood sugar meter:

What Can Affect Your A1C Result?

Get your A1C tested in addition to—not instead of—regular blood sugar self-testing if you have diabetes.

Several factors can falsely increase or decrease your A1C result, including:

• Kidney failure, liver disease, or severe anemia.
• A less common type of hemoglobin that people of African, Mediterranean, or Southeast Asian descent and people with certain blood disorders (such as sickle cell anemia or thalassemia) may have.
• Certain medicines, including opioids and some HIV medications.
• Blood loss or blood transfusions.
• Early or late pregnancy.

Let your doctor know if any of these factors apply to you, and ask if you need additional tests to find out.

Your A1C Goal

The goal for most people with diabetes is 7% or less. However, your personal goal will depend on many things such as your age and any other medical conditions. Work with your doctor to set your own individual A1C goal.

Younger people have more years with diabetes ahead, so their goal may be lower to reduce the risk of complications, unless they often have hypoglycemia (low blood sugar, or a “low”). People who are older, have severe lows, or have other serious health problems may have a higher goal.

A1C: Just Part of the Toolkit

A1C is an important tool for managing diabetes, but it doesn’t replace regular blood sugar testing at home. Blood sugar goes up and down throughout the day and night, which isn’t captured by your A1C. Two people can have the same A1C, one with steady blood sugar levels and the other with high and low swings.

If you’re reaching your A1C goal but having symptoms of highs or lows, check your blood sugar more often and at different times of day. Keep track and share the results with your doctor so you can make changes to your treatment plan if needed.

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Ways to Lower Your A1C

For some, home blood sugar testing can be an important and useful tool for managing blood sugar on a day-to-day basis. Still, it only provides a snapshot of what’s happening in the moment, not the full picture of what’s happened in the long term, says Gregory Dodell, MD, an assistant clinical professor of medicine, endocrinology, diabetes, and bone disease at Mount Sinai in New York City.

For this reason, your doctor may occasionally administer a blood test that measures your average blood sugar level over the past three months. Called hemoglobin A1C, or A1C, this test can show you how well your type 2 diabetes management plan is working.

Here’s what you should know about it and ways to make sure your A1C is in a healthy range.

   Poll

How often do you get your A1C tested?

How Often Do You Need to Take an A1C Test?

If your blood sugar levels have remained stable and your A1C is within your target range, the American Diabetes Association (ADA) recommends getting the test two times a year. If your therapy has changed or you are not meeting your blood sugar targets, the ADA recommends getting the test four times per year. This simple blood draw can be done in your doctor’s office.

The A1C test results provide insight into how your treatment plan is working and how it might be modified to better control the condition. Often, your blood sample is sent out to a lab, though some doctors can use a point-of-care A1C test, where a finger stick can be done in the office, with results available in about 10 minutes.

While in-office tests can be used to monitor the disease, the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) notes that most point-of-care tests should not be used for diagnosis. That can only be done by lab tests certified by the NGSP, an organization that standardizes A1C test results. Any in-office test results pointing to a change in your health should be confirmed by conventional lab tests.

What Do Your A1C Results Mean?

The A1C test measures the glucose (blood sugar) in your blood by assessing the amount of what’s called glycated hemoglobin. “Hemoglobin is a protein within red blood cells. As glucose enters the bloodstream, it binds to hemoglobin. The more glucose that enters the bloodstream, the higher the amount of glycated hemoglobin,” Dr. Dodell says.

According to the ADA, an A1C level below 5.7 percent is considered normal; between 5.7 and 6.4 signals prediabetes; and over 6.5 percent indicates type 2 diabetes. For many people with type 2 diabetes, the goal is to reduce A1C levels.

Your A1C goal is specific to you. Several factors come into play, such as your age, how advanced the diabetes is, and whether you have any other health conditions. If you can keep your A1C number below your goal — which, for many people with diabetes, is less than 7 percent, says Dodell — you can reduce the risk of complications, such as nerve damage and eye problems.

What Are Some Top Tips for Lowering A1C?

Your A1C score is a helpful tool, Dodell says, but it is not the only indicator of how healthy you are.

For example, you could hit your A1C goal but still have wide fluctuations in your blood sugar levels, which is more common among people who take insulin. You’ll need to bring these day-to-day fluctuations under control, since they can lower your quality of life and increase your risk of complications, he says.

Think of your diabetes as you would a job, Dodell says. It takes work, but the time and effort you put into it can result in good control and an improved quality of life. “The key to reaching your A1C goal is trying to follow a healthy lifestyle,” he says.

Making these changes can help you improve your day-to-day blood sugar management and lower your A1C.

1. Start an Exercise Plan You Enjoy, and Do It Regularly

Find something you enjoy doing that gets your body moving, whether it’s taking your dog for a walk, playing a sport with a friend, or riding your bike.

The ADA recommends getting 150 minutes of moderate exercise per week, says Jordana Turkel, a certified diabetes care and education specialist (CDCES) and registered dietitian at Park Avenue Endocrinology & Nutrition in New York City.  Different types of exercise (both strength or resistance training and aerobic exercise) can lower your A1C by making your body more sensitive to insulin, Turkel says. She encourages her patients not to go more than two days in a row without exercising and to aim for two days of strength training per week.

Be sure to check with your healthcare provider before embarking on an exercise plan, though. Together, you can come up with an individualized plan.

And if you monitor your blood sugar daily, check it before and after exercise. As the ADA explains, exercise improves insulin sensitivity and lowers your blood sugar levels. In certain circumstances, though, stress hormones produced during more intense exercise can also increase blood sugar levels. In addition, other factors, such as what you eat before exercise and the timing of your workout, may also affect your numbers.

2. Eat a Balanced Diet With Proper Portion Sizes

It’s best to check with a CDCES or registered dietitian/nutritionist to determine what a balanced diet and appropriate portion sizes mean for you. But a great rule of thumb is to fill half of your plate with veggies, a quarter with protein, and a quarter with whole grains, says Turkel. If you like fruit, limit your portion to a small cup, eaten with a little protein or lean fat to help you digest the carbohydrates in a way that is less likely to spike your blood sugar.

Also, avoid processed foods as much as possible, and try to avoid sugary sodas and fruit juice, which are high in carbs and calories, and thus can lead to spikes in blood sugar and contribute to weight gain, according to the ADA.

3. Stick to a Regular Schedule, So You Can More Easily Follow a Healthy Diet 

Skipping meals, letting too much time pass between meals, or eating too much or too often can cause your blood sugar levels to fall and rise too much, Cleveland Clinic points out. This is especially true if you are taking insulin or certain other diabetes drugs. Your doctor can help you determine the best meal schedule for your lifestyle.

4. Follow the Diabetes Treatment Plan Your Healthcare Team Recommends

Diabetes treatment is very individualized, noted a February 2022 article in Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy. After all, factors including how long you’ve lived with the disease, your socioeconomic status, and any other conditions you’re living with can play a role in the best treatment approach for you.

Your healthcare team will help you determine which steps to take to successfully manage diabetes. Always talk to your doctor before making any changes, such as starting a diet very low in carbohydrates or beginning a new exercise regimen. This is especially important before making any medication or insulin changes.

5. Check Your Blood Sugar Levels as Your Doctor Has Directed

Work with your doctor to determine if you should check your blood sugar — and how often. You may be tempted to pick up an A1C home testing kit, but Dodell says having your A1C checked by your doctor every three to six months is sufficient. A better idea is to use a continuous glucose monitor. He recommends checking your “time in range” to see if you are at the optimal level. For many people that is 70 to 180 milligrams per deciliter (3.9 to 10 millimoles per liter), according to ADA guidelines.

Understanding your A1C levels is an important part of your overall diabetes management. If you have any questions about your A1C or what it means, don’t hesitate to ask your doctor.

Additional reporting by Mikel Theobald

Glycated hemoglobin (HbA1c)

Glycated hemoglobin (A1c) is a specific compound of erythrocyte hemoglobin with glucose, the concentration of which reflects the average blood glucose over a period of about three months.

Synonyms Russian

Glycohemoglobin, hemoglobin A1c, Hb _A1c , glycosylated hemoglobin.

English synonyms

Glycated hemoglobin, hemoglobin A1c, HbA1c, glycohemoglobin, glycosylated hemoglobin.

Test method *

Ion exchange high performance liquid chromatography (HPLC).

* Method may vary in some regions.

Units

% (percentage).

What biomaterial can be used for research?

Venous blood.

How to properly prepare for an examination?

• Do not eat for 2-3 hours before the examination, you can drink pure non-carbonated water.
• Exclude physical and emotional overexertion within 30 minutes prior to the study.
• Do not smoke for 30 minutes before the test.

Overview of the study

The glycated hemoglobin (A1c) test helps to assess the average blood glucose level over the past 2-3 months.

Hemoglobin is an oxygen-carrying protein found inside red blood cells (erythrocytes). There are several types of normal hemoglobin, and many abnormal varieties have been identified, although the predominant form is hemoglobin A, which is 95-98% of total hemoglobin. Hemoglobin A is divided into several components, one of which is A1c. Part of the glucose circulating in the blood spontaneously binds to hemoglobin, forming the so-called glycated hemoglobin. The higher the concentration of glucose in the blood, the more glycated hemoglobin is formed. Having combined with hemoglobin, glucose remains “in conjunction” with it until the very end of the life of the erythrocyte, that is, 120 days. The combination of glucose with hemoglobin A is called HbA1c or A1c. Glycated hemoglobin is formed in the blood and disappears from it every day, as old red blood cells die, and young (not yet glycated) take their place.

The hemoglobin A1c test is used to monitor the condition of patients diagnosed with diabetes mellitus. It helps to assess how effectively the regulation of glucose levels during treatment is going on.

For some patients, a hemoglobin A1c test is prescribed to diagnose diabetes and pre-diabetes in addition to a fasting plasma glucose test and a glucose tolerance test.

The resulting value is measured as a percentage. Patients with diabetes should strive to keep their glycated hemoglobin levels below 7%.

A1c should be reported in one of three ways:

• as a percentage of total hemoglobin,
• in mmol/mol, according to the International Federation of Clinical Chemistry and Laboratory Medicine,
• as mean glucose mg/dl or mmol/l.

What is research used for?

• For the control of glucose in patients with diabetes mellitus – for them to maintain its level in the blood as close to normal as possible is very important. This helps to minimize complications to the kidneys, eyes, cardiovascular and nervous systems.
• To determine the patient’s average blood glucose over the past few months.
• To validate the correctness of the measures taken for the treatment of diabetes and to find out if they need to be adjusted.
• To detect uncontrolled rises in blood glucose in patients with newly diagnosed diabetes mellitus. Moreover, the test may be prescribed several times until the desired glucose level is detected, then it needs to be repeated several times a year to make sure that the normal level is maintained.
• For preventive purposes, to diagnose diabetes at an early stage.

When is the test ordered?

Depending on the type of diabetes and how well the disease is treated, A1c is tested 2 to 4 times a year. On average, patients with diabetes are recommended to be tested for A1c twice a year. If the patient is diagnosed with diabetes for the first time or the control measurement fails, the analysis is re-assigned.

In addition, this test is ordered if the patient is suspected of having diabetes because there are symptoms of high blood glucose:

• extreme thirst,
• frequent copious urination,
• fatigue,
• blurred vision,
• increased susceptibility to infections.

What do the results mean?

Reference values: * 4. 27 – 6.07%.

*Reference values ​​vary for some regions due to the use of different test systems for the study.

The closer the A1c level is to 7% in a diabetic patient, the easier it is to control the disease. Accordingly, with an increase in the level of glycated hemoglobin, the risk of complications also increases.

The results of the analysis for A1c are interpreted as follows.

According to the clinical guidelines of the Ministry of Health of the Russian Federation of the NGO “Russian Association of Endocrinologists” “Algorithms for specialized medical care for patients with diabetes mellitus” (2019), an additional diagnostic indicator is the average daily plasma glucose level (AGG) for the last three months and its correlation with the level HbA1c.

What can influence the result?

Patients with abnormal hemoglobin, such as those with sickle cells, will have low glycated hemoglobin. In addition, if a person suffers from anemia, severe bleeding, his test results may also be underestimated. On the contrary, A1c values ​​are overestimated with iron deficiency and with a recent blood transfusion (since liquid blood preservatives contain a high concentration of glucose).

Important notes

The A1c test does not reflect sudden changes in blood glucose. Glucose fluctuations in patients with labile diabetes will also not be detected by this test.

Also recommended

• Plasma glucose
• Glucose tolerance test
• Fructosamine

Who orders the examination?

Therapist, endocrinologist.

What you need to know about HbA1C

Among the many numbers of test results that doctors prepare, a simple HbA1C test value can help you figure out how well you’re monitoring your blood sugar levels.

First of all, let’s find out what is HbA1C?

You can find different names for this indicator:

• A1c
• Glycated hemoglobin
• Glycosylated hemoglobin
• Hemoglobin A1C

The level of HbA1C (glycated hemoglobin) shows what percentage of hemoglobin in erythrocytes binds to glucose ¹ . Since the lifetime of a red blood cell that contains hemoglobin is several months, the HbA1C test allows you to determine how effective blood sugar control was in the previous 2-3 months.

How often should I check my HbA1C level?

The American Diabetes Association (ADA) recommends that diabetic patients with stable blood sugar levels have an HbA1C test every six months, and if blood sugar targets cannot be achieved or treatment needs to be changed, this test is done every 3 months ² .

What level of HbA1C should I aim for?

The American Diabetes Association recommends that HbA1C levels be 7% or lower, and the closer this is to 6% without risk to health, the better. However, for each person, this level should be set depending on the current state of health and taking into account many factors (in particular, whether the person feels the onset of hypoglycemia). Most likely, if your HbA1C level exceeds 7%, then the doctor will advise you on what needs to be done to lower it, because, among other things, lowering this indicator helps to reduce the risk of long-term complications of diabetes, which we strive to prevent ² .

Is it possible to do without blood sugar measurement if an HbA1C test is done?

Since the HbA1C level is an average value, it cannot guarantee that blood sugar levels during the day are in a safe range. Let’s see what the average value means. The average of the numbers 5-5-5-5 and the numbers 1-9-1-9 will be 5, but on the chart, the numbers 1-9-1-9 will look like sharp ups and downs. This also applies to blood sugar levels. If there are many highs and lows after averaging, the HbA1C level may be similar to the HbA1C level of a healthy person ³ .

Therefore, it is best to evaluate HbA1C test results when self-monitoring blood sugar results are available. It is impossible to understand how the disease develops if you do not conduct self-monitoring of blood sugar levels.

If HbA1C is low, does fluctuating blood sugar matter?

Blood sugar levels tend to fluctuate throughout the day, and this is due to what we eat, how much we move and rest. Currently, along with the results of the analysis of HbA1C, high glycemic variability is also being evaluated – this is how these fluctuations in blood sugar levels are called.

Data from the Diabetes Control and Complications Trial (DCCT ⁴ ) showed that patients with the same level of HbA1C were more susceptible to certain types of complications with more pronounced fluctuations in blood sugar levels. blood.

If you want to know if you are at risk and how your actions affect your blood sugar levels, the Accu-Chek 360° Form (Blood Glucose Test: Before and After Meals) can help you understand how food, exercise, medication, stress, or illness can affect your sugar levels throughout the day.