What Are A1C Levels and Why Do They Matter?

What Are A1C Levels and Why Do They Matter?

More than 29 million Americans are estimated to struggle with some form of diabetes, according to statistics from the American Diabetes Association. The number of patients diagnosed with this disease continues to increase every year, making regular testing important for those at risk. One of the primary tests that can be used to measure your individual risk is the A1C test.


An A1C test, also referred to as a glycosylated hemoglobin or glycated hemoglobin test, is a form of blood test that measures your average levels of blood glucose (blood sugar) over a period of several months. While only one blood draw is typically necessary, the results allow a physician to estimate your average blood sugar levels over about a 3 month period. An additional benefit is that unlike a fasting glucose test, you can eat normally before your appointment.

How It Works

The A1C looks specifically at the hemoglobin in your blood. Hemoglobin are proteins in red blood cells that help transport oxygen from the lungs to all the cells in your body. Glucose also attaches itself to hemoglobin, or glycates, in order to be transported to your cells as part of the process of creating energy. Higher blood sugar levels result in a greater percentage of hemoglobin being coated with glucose. The A1C test looks at this percentage and uses it to measure your risks of diabetes as well as whether you can be diagnosed with the disease.


A1C levels are checked when your doctor is worried about your risks for developing diabetes, or if you already have diabetes, is worried about potential complications from the disease. The test is performed once during your first diagnosis to give a baseline number for a treatment plan. How often you need to have the test performed after initial testing depends on your risk factors. For example, those who are pre-diabetic may only need one test a year. Those who have just been diagnosed with type 2 diabetes, and are just learning to self-monitor their daily levels, typically have the test done twice a year. Finally, those who are at high risk of complications from the disease, and are currently using insulin regularly to control their rapidly fluctuating blood sugar levels, may have the test performed four times per year.


A healthy percentage number for an A1C test varies depending on the patient. However, generally keeping A1C levels below 7 percent is considered healthy. For others, a less strict A1C percentage between 7 and 8 may be more optimal, especially for those who have a history of hypoglycemia, or low blood sugar. Too strict of control could lead to dangerously low blood glucose levels.

While it’s important for everyone to pay attention to their blood sugar levels, certain circumstances require extra attention. This includes factors like being inactive or overweight, as well as having issues like irregular cholesterol levels or high blood pressure. Talk to your doctor about your individual risk factors and whether an A1C test is appropriate for your preventive health plan.