UNC Health Care

A1C and Diabetes

If you’ve been diagnosed with diabetes or prediabetes, you may have heard the term “A1C.” This is a blood test that measures your average blood sugar level over the last 90 to 120 days, and it’s a powerful tool for staying healthy.

“A1C is the yardstick of blood sugar,” says UNC Health diabetes educator Camille B. Izlar.

Diabetes is characterized by excess sugar in your blood, and too much blood sugar can wreak havoc on your body, causing serious health problems such as heart disease and stroke.

The A1C test differs from a basic blood sugar test, which is performed with a finger prick and can be done at home. A blood sugar test tells you how much glucose is in your blood at that exact moment; for example, a fasting blood test result of 100-125 mg/dL is prediabetes; 126 mg/dL or above indicates diabetes.

A1C is a longer-term picture. Your provider draws blood that is tested in a lab to see what percentage of red blood cells have a glucose coating. A result of 5.7 percent to less than 6.5 percent indicates prediabetes; anything 6.5 percent or higher is diabetes.

“A1C tells how much glucose, or sugar, has been attached to your red blood cells over that period of three months,” Izlar says. It can be used to confirm a blood sugar test that shows diabetes or prediabetes.

Why Is It Important to Know Your A1C?

A1C can be used to diagnose diabetes, and your healthcare provider will use it regularly to determine how well you are managing your diabetes. Knowing your blood sugar levels means you can better control your diabetes.

If your blood sugar levels are stable, the American Diabetes Association (ADA) recommends getting your A1C test twice a year. If you are not meeting your blood sugar targets, the ADA recommends getting it four times per year.

A higher A1C level usually means your blood sugar is too high, which increases your risk of diabetes complications such as eye disease, kidney disease and neuropathy (nerve damage), Izlar says.

“Our goal is for A1C to be 7 percent or less, and that’s an average blood sugar of 150 (mg/DL) or less,” Izlar says. “So all the things that people with diabetes fear, these long-term complications, can almost be eradicated if your A1C stays in that range all the time.”

A1C also guides your healthcare provider when he or she makes decisions about your medications.

“For example, if we change somebody’s meds in three months, we want to do an A1C test to see if her A1C comes into range, and if not, why? Do we need to do something different?” Izlar says.

How To Lower Your A1C

If your A1C is elevated, you need to take action, Izlar says. Your healthcare provider may prescribe medication to help, but there are additional ways to lower your blood sugar levels:

  • Exercise regularly. Even a gradual increase in your activity will help lower your A1C.
  • Eat a balanced, low-carb diet. If you’re trying to reduce sugar in your bloodstream, avoid it in your diet.
  • Avoid skipping meals to prevent fluctuations in your blood sugar.
  • Check your blood sugar levels as directed by your healthcare provider.

If you are concerned about your A1C levels or diabetes, talk to your doctor. Need a doctor? Find one here.