Understanding Your A1C

The A1C is a blood test that helps determine if your diabetes management plan is working well. (Both type 1 and type 2 take this test.) It’s done every two to three months to find out what your average blood sugar has been. (You may also hear this test called glycosylated hemoglobin, glycohemoglobin, hemoglobin A1c and HbA1c.) A1c is the most common name for it though.

How the test works

Essentially, the test can tell how much sugar is in the blood stream by looking for proteins (hemoglobins). When glucose (sugar) enters the blood, it binds to the protein in the red blood cells. This binding creates “glycated hemoglobin”. The more sugar in the blood, the more glycated hemoglobin.

It’s important to test your blood sugar levels (BGLs) throughout the day; however, an A1C test gives you a bigger picture with a long-term average of those blood sugar levels.

What do these numbers mean?

The A1c is an average of what your blood sugar levels have been over the three-month period. In general, the higher your A1C number, the higher your likelihood of diabetes complications. (You don’t want a high A1C; it means there is too much sugar in your blood and your body isn’t absorbing it.)

A1C number

This target range varies between individuals, some people naturally run a little higher, some lower. It is important to note that especially in children a higher A1C (of 7.5) is recommended. The A1C number will help you and your doctor determine though if your diabetes management plan is working well.

Learn more about children’s A1C target range.

Sometimes the test isn’t accurate, and here’s why:

• If you are bleeding a lot, the protein (hemoglobin) in your red bold cells may be low, so it could say your A1C is lower than it actually is.
• If you’ve just had a blood transfusion or have other forms of hemolytic anemia, your A1C test results may be lower than it actually is.
• If you are low in iron in the blood, your A1C test results may be higher than it actually is.
• If you have a special hemoglobin (variant). Most people have hemoglobin A. With the variant, you can be falsely high or low. A lab test can be done to see which one you are and special lab tests can then give you an accurate A1C. (Hemoglobin variants are mostly found in Black, Mediterranean and Southeast Asian populations.)
• A new lab can give different results as well. Keep this in mind if your results were sent away to a new facility. It could account for minor reading variations.

Translating your A1c to an average blood sugar level

What’s a “perfect A1C”?

This is often said when someone with diabetes has met their A1C target range, (which is 5-7). Keep in mind that an A1C test like any other BGL reading is just information to guide you in your diabetes management. Some run higher while others run low—it really depends on the individual. This number can vary wildly too throughout your life. Consult your doctor to find a target A1C range and a diabetes plan that works for you.

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