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A1C

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

Blood Glucose

What is blood glucose?

Blood glucose, or blood sugar, is the main sugar found in your blood. It is your body's primary source of energy. It comes from the food you eat. Your body breaks down most of that food into glucose and releases it into your bloodstream. When your blood glucose goes up, it signals your pancreas to release insulin. Insulin is a hormone that helps the glucose get into your cells to be used for energy.

What is diabetes?

Diabetes is a disease in which your blood glucose levels are too high. When you have diabetes, your body doesn't make enough insulin, can't use it as well as it should, or both. Too much glucose stays in your blood and doesn't reach your cells. Over time, having too much glucose in your blood can cause serious health problems (diabetes complications). So if you have diabetes, it's important to keep your blood glucose levels within your target range.

What are blood glucose targets?

If you have diabetes, your blood glucose target is the range you try to reach as much as possible. The typical targets are:

  • Before a meal: 80 to 130 mg/dL
  • Two hours after the start of a meal: Less than 180 mg/dL

Your blood glucose targets may be different, depending on your age, any additional health problems you have, and other factors. Talk with your health care team about the best target range for you.

When and how should I check my blood glucose?

If you have diabetes, you'll likely need to check your blood glucose every day to make sure that your blood glucose numbers are in your target range. Some people may need to check their blood glucose several times a day. Ask your health care team how often you need to check it.

The most common way to check your blood glucose level at home is with a blood glucose meter. A blood glucose meter measures the amount of glucose in a small sample of blood, usually from your fingertip.

Continuous glucose monitoring (CGM) is another way to check your glucose levels. Most CGM systems use a tiny sensor that is inserted under your skin. The sensor measures your glucose level every few minutes. It can show changes in your glucose level throughout the day and night. A CGM system is especially useful for people who take insulin and have problems with low blood glucose.

Your provider will also check your blood glucose with a blood test called an A1C. It checks your average blood glucose level over the past three months. People with diabetes usually have an A1C test at least twice a year. But you may need the test more often if you aren't meeting your diabetes treatment goals.

What happens if my blood glucose level becomes too high?

High blood glucose is called hyperglycemia. Symptoms that your blood glucose levels may be too high include:

  • Feeling thirsty
  • Feeling tired or weak
  • Headaches
  • Urinating (peeing) often
  • Blurred vision

If you often have high blood glucose levels or symptoms of high blood glucose, talk with your health care team. You may need a change in your diabetes meal plan, physical activity plan, or diabetes medicines.

High blood glucose may also be caused by other conditions that can affect insulin or glucose levels in your blood. These conditions include problems with your pancreas or adrenal glands.

What happens if my blood glucose level becomes low for me?

Hypoglycemia, also called low blood glucose, happens when your blood glucose level drops below what is healthy for you. For many people with diabetes, this means a blood glucose reading lower than 70 mg/dL. Your number might be different, so check with your health care team to find out what blood glucose level is low for you.

Symptoms of low blood glucose tend to come on quickly. The symptoms can be different for everyone, but they may include:

  • Shaking
  • Sweating
  • Nervousness or anxiety
  • Irritability or confusion
  • Dizziness
  • Hunger

Low blood glucose levels can be common in people with type 1 diabetes and people with type 2 diabetes who take certain diabetes medicines. If you think you may have low blood glucose, check your level, even if you don't have symptoms. Low blood glucose can be dangerous and should be treated as soon as possible.

Although it's rare, you can still get low blood glucose without having diabetes. The causes can include conditions such as liver disease, kidney disease, and hormone deficiencies (lack of certain hormones). Some medicines, such as certain heart medicines and antibiotics, can also cause it. See your provider to find out the cause of your low blood glucose and how to treat it.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Diabetes

What is diabetes?

Diabetes, also known as diabetes mellitus, is a disease in which your blood glucose, or blood sugar, levels are too high. Glucose is your body's main source of energy. Your body can make glucose, but it also comes from the food you eat. Insulin is a hormone made by your pancreas. Insulin helps move glucose from your bloodstream into your cells, where it can be used for energy.

If you have diabetes, your body can't make insulin, can't use insulin as well as it should, or both. Too much glucose stays in your blood and doesn't reach your cells. This can cause glucose levels to get too high. Over time, high blood glucose levels can lead to serious health conditions. But you can take steps to manage your diabetes and try to prevent these health problems.

What are the types of diabetes?

There are different types of diabetes:

  • Type 1 diabetes. If you have type 1 diabetes, your body makes little or no insulin. It happens when your immune system attacks and destroys the cells that produce insulin.
  • Type 2 diabetes. This is the most common form of diabetes. If you have type 2 diabetes, your body may still be able to make insulin, but your cells don't respond well to insulin. They can't easily take up enough glucose from your blood.
  • Gestational diabetes. This is a form of diabetes that develops during pregnancy. It happens when your body can't make the extra insulin it needs during pregnancy.
What causes diabetes?

The different types of diabetes have different causes:

  • Researchers think type 1 diabetes is caused by genes and factors in the environment that might trigger the disease.
  • Type 2 diabetes is caused by several factors, including lifestyle factors and genes. The lifestyle factors include not being physically active and being overweight or having obesity.
  • Researchers think gestational diabetes is caused by the hormonal changes of pregnancy along with genetic and lifestyle factors.
Who is more likely to develop diabetes?

The different types of diabetes have different risk factors:

  • You can develop type 1 diabetes at any age, but it most often starts in childhood. Having a parent or sibling with type 1 diabetes may increase your chance of developing it.
  • You are at higher risk of developing type 2 diabetes if you:
    • Are overweight or have obesity.
    • Are over age 35. Children, teenagers, and younger adults can get diabetes, but it is more common in middle-aged and older adults.
    • Have a family history of diabetes.
    • Have prediabetes. This means that your blood glucose is higher than normal, but it's not high enough to be called diabetes.
    • Had gestational diabetes.
    • Have given birth to a baby weighing 9 pounds or more.
    • Are African American, American Indian, Asian American, Hispanic/Latino, or Pacific Islander.
    • Are not physically active.
    • Have certain other health conditions, such as high blood pressure or polycystic ovary syndrome (PCOS).
  • You are at higher risk of developing gestational diabetes if you:
    • Are overweight or have obesity.
    • Have a family history of diabetes.
    • Had gestational diabetes in a previous pregnancy.
    • Have given birth to a baby weighing 9 pounds or more.
    • Have polycystic ovary syndrome (PCOS).
    • Are African American, Hispanic/Latino, American Indian, Alaska Native, Native Hawaiian, or Pacific Islander.
What are the symptoms of diabetes?

The symptoms of diabetes may include:

  • Feeling very thirsty
  • Feeling very hungry
  • Urinating (peeing) more often, including at night
  • Fatigue
  • Blurry vision
  • Numbness or tingling in the feet or hands
  • Sores that do not heal
  • Losing weight without trying

But it's important to know that your symptoms may vary, depending on which type you have:

  • The symptoms of type 1 diabetes usually come on quickly and can be severe.
  • With type 2 diabetes, the symptoms often develop slowly, over several years. The symptoms can be so mild that you might not even notice them.
  • Gestational diabetes often has no symptoms. If you do have symptoms, they may be mild. If you are pregnant, you will usually be screened for this condition between 24 and 28 weeks of pregnancy.
How is diabetes diagnosed?

To find out if you have diabetes, your health care provider will use one or more glucose blood tests. There are several types, including the A1C test.

What are the treatments for diabetes?

Treatment for diabetes involves managing your blood glucose levels:

  • If you have type 1 diabetes, you will need to take daily doses of insulin, either by injection or through a special pump. Some people also need to take another type of diabetes medicine that works with insulin.
  • If you have type 2 diabetes, you may be able to manage or even reverse it by making lifestyle changes. These include eating a healthy diet, staying at healthy weight, and getting regular physical activity. Some people also need to take diabetes medicines to manage their diabetes.
  • If you have gestational diabetes, you may be able to lower your glucose levels by eating a healthy diet and getting regular exercise. But be sure to talk to your provider about your treatment options. Gestational diabetes usually goes away after you give birth. But you will have a higher risk of developing type 2 diabetes later.

Checking your blood glucose levels is also an important part of managing your diabetes. Ask your provider about the best way to check your blood glucose level and how often you should check it.

Can diabetes be prevented?

Type 1 diabetes can't be prevented.

You may be able to delay or prevent type 2 diabetes through the same lifestyle changes that are used to manage diabetes (eating a healthy diet, staying at a healthy weight, and getting regular physical activity). These lifestyle changes may also help prevent gestational diabetes.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Prediabetes

What is prediabetes?

Prediabetes means that your blood glucose, or blood sugar, levels are higher than normal but not high enough to be called diabetes. Glucose comes from the foods you eat. Too much glucose in your blood can damage your body over time.

If you have prediabetes, you are more likely to develop type 2 diabetes, heart disease, and stroke. But if you make some lifestyle changes now, you may be able to delay or prevent type 2 diabetes.

What causes prediabetes?

Prediabetes usually happens when your body has a problem with insulin. Insulin is a hormone that helps the glucose get into your cells to give them energy. A problem with insulin could be:

  • Insulin resistance, a condition in which the body can't use its insulin properly. It makes it hard for your cells to get glucose from your blood. This can cause your blood sugar levels to rise.
  • Your body can't make enough insulin to keep your blood sugar levels at a healthy level

Researchers think that being overweight and not getting regular physical activity are major factors in causing prediabetes.

Who is at risk for prediabetes?

About 1 out of every 3 adults has prediabetes. It is more common in people who:

  • Are overweight or have obesity
  • Are age 45 or older
  • Have a parent, brother, or sister with diabetes
  • Are African American, Alaska Native, American Indian, Asian American, Hispanic/Latino, Native Hawaiian, or Pacific Islander American
  • Are not physically active
  • Have health conditions such as high blood pressure and high cholesterol
  • Have had gestational diabetes (diabetes in pregnancy)
  • Have a history of heart disease or stroke
  • Have metabolic syndrome
  • Have polycystic ovary syndrome (PCOS)
What are the symptoms of prediabetes?

Most people don't know they have prediabetes because usually there are no symptoms.

Some people with prediabetes may have darkened skin in the armpit or on the back and sides of the neck. They may also have many small skin growths in those same areas.

How is prediabetes diagnosed?

There are a few different blood tests that can diagnose prediabetes. The most common ones are:

  • Fasting plasma glucose (FPG) test, which measures your blood sugar at a single point in time. You need to fast (not eat or drink) for at least 8 hours before the test. The results of the test are given in mg/dL (milligrams per deciliter):
    • A normal level is 99 or below
    • Prediabetes is 100 to 125
    • Type 2 diabetes is 126 and above
  • A1C test, which measures your average blood sugar over the past 3 months. The results of an A1C test are given as a percentage. The higher the percentage, the higher your blood sugar levels have been.
    • A normal level is below 5.7%
    • Prediabetes is between 5.7 to 6.4%
    • Type 2 diabetes is above 6.5%
If I have prediabetes, will I get diabetes?

If you have prediabetes, you may be able to delay or prevent type 2 diabetes through lifestyle changes:

  • Losing weight, if you are overweight
  • Getting regular physical activity
  • Following a healthy, reduced-calorie eating plan

In some cases, your health care provider may also recommend taking diabetes medicines.

Can prediabetes be prevented?

If you are at risk for prediabetes, those same lifestyle changes (losing weight, regular physical activity, and a healthy eating plan) may prevent you from getting it.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Diabetes in Children and Teens

Until recently, the common type of diabetes in children and teens was type 1. It was called juvenile diabetes. With Type 1 diabetes, the pancreas does not make insulin. Insulin is a hormone that helps glucose,or sugar, get into your cells to give them energy. Without insulin, too much sugar stays in the blood.

Now younger people are also getting type 2 diabetes. Type 2 diabetes used to be called adult-onset diabetes. But now it is becoming more common in children and teens, due to more obesity. With Type 2 diabetes, the body does not make or use insulin well.

Children have a higher risk of type 2 diabetes if they are overweight or have obesity, have a family history of diabetes, or are not active. Children who are African American, Hispanic, Native American/Alaska Native, Asian American, or Pacific Islander also have a higher risk. To lower the risk of type 2 diabetes in children:

  • Have them maintain a healthy weight
  • Be sure they are physically active
  • Have them eat smaller portions of healthy foods
  • Limit time with the TV, computer, and video

Children and teens with type 1 diabetes may need to take insulin. Type 2 diabetes may be controlled with diet and exercise. If not, patients will need to take oral diabetes medicines or insulin. A blood test called the A1C can check on how you are managing your diabetes.