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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

Diabetes is a disease in which your blood glucose, or blood sugar, levels are too high. Glucose comes from the foods you eat. Insulin is a hormone that helps the glucose get into your cells to give them energy. With type 1 diabetes, your body does not make insulin. With type 2 diabetes, the more common type, your body does not make or use insulin well. Without enough insulin, the glucose stays in your blood. You can also have prediabetes. This means that your blood sugar is higher than normal but not high enough to be called diabetes. Having prediabetes puts you at a higher risk of getting type 2 diabetes.

Over time, having too much glucose in your blood can cause serious problems. It can damage your eyes, kidneys, and nerves. Diabetes can also cause heart disease, stroke and even the need to remove a limb. Pregnant women can also get diabetes, called gestational diabetes.

Blood tests can show if you have diabetes. One type of test, the A1C, can also check on how you are managing your diabetes. Exercise, weight control and sticking to your meal plan can help control your diabetes. You should also monitor your blood glucose level and take medicine if prescribed.

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.