What is A1C?
Your A1C test measures your average blood sugar levels over a three-month period by taking a sample of hemoglobin A1C molecules—a specific component of your red blood cells.
Some blood sugar (or glucose) naturally attaches itself to these A1C molecules as they move through your bloodstream. When this happens, the molecule is considered "glycated." The more sugar in your blood, the higher the percentage of glycated A1C molecules you'll have.1
Once a cell has been glycated, it stays that way. And since each A1C molecule has a lifespan of about four months, your A1C sample will include cells that are a few days, a few weeks and a few months old. That's how the test result covers a span of about three months.
Of course, without regular self-testing to provide day-to-day insights, an A1C result can be misleading.1 Because it gives a long-term view, a person with frequent highs and lows could have an average A1C that looks quite healthy.2 The only way to get a complete picture of your blood sugar control is by reviewing your daily log along with your regular A1C tests, and working closely with your healthcare team to interpret the results.
To learn more about your A1C, visit the Diabetes Care Coalition.
1 American Diabetes Association, "A1C Test." Available at http://www.diabetes.org/type-1-diabetes/a1c-test.jsp. Accessed November 7, 2007.
2 Medscape Today. "How Should Hemoglobin A1c (HbA1c) Results Be Interpreted in Your Patients with Diabetes?" Available at: http://www.medscape.com/viewarticle/413375. Accessed November 7, 2007.