The hemoglobin A1C blood test is used to diagnose both type 1 and type 2 diabetes, as well as to gauge how well you are managing your diabetes.
Whereas the ubiquitous finger-stick test measures your blood sugar level at the time you test, the hemoglobin A1C test calculates your average blood sugar level over a six- to eight-week period. It does this by measuring how much of your hemoglobin has become glycated, or coated with excess blood sugar. The higher your A1C value, the worse your blood sugar control.
I strongly prefer the hemoglobin A1C test over finger-stick testing because it is a better measure of how well you are managing your diabetes, and if your diabetes treatment plan is working over the long term.
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