The ABCs of an A1C Test: A Big-Picture Look at Diabetes Control

Jo-Anne Rizzotto 2004V3This post is written by Jo-Anne M. Rizzotto, M.Ed., R.D., L.D.N.,C.D.E., Registered Dietitian and Certified Diabetes Educator, and Director of Educational Services at Joslin Diabetes Center.

If you are talking with someone about diabetes, you may hear the term “A1C.” But what exactly does A1C mean? And why is your A1C important for diabetes management?

The A1C, otherwise known as a glycohemoglobin or hemoglobin A1C test, provides a picture of your average blood glucose control for the two to three months before you take the test. The A1C measures the glucose that clings to hemoglobin molecules in your red blood cells. The higher the glucose levels in your blood, the more glucose clings to the hemoglobin, and thus the higher your A1C level will be. Red blood cells are renewed every 120 days. By measuring the percentage of hemoglobin molecules that have glucose attached to them, healthcare providers can see how much extra glucose you have had in your bloodstream over the past few months.

The A1C test is done every three to six months, often during a regular diabetes care visit. It does not require fasting, can be done any time of day, and requires only a small sample of blood taken from a finger stick or drawn from your arm.

How to Use Your A1C Results to Manage Your Diabetes

Why is the A1C test essential for diabetes management? It gives you an overall picture of your diabetes, rather than a reflection of what is happening in one day, and helps you evaluate your diabetes care and make changes.

An A1C test can help you manage your diabetes by:

1.)  verifying self-testing or other blood test results with your healthcare provider
2.) determining whether your treatment plan is working
3.) demonstrating how healthy food choices and being physically active affect diabetes control

An A1C reading of less than 7 percent may be a good goal for many people, but make sure to ask your provider what your A1C target should be. It’s helpful to remember that the closer you get to your goal, the better you’ll feel today and tomorrow. According to Joslin Diabetes Center’s Clinical Guidelines, we recommend that patients aim for an A1C value of less than 7 percent, as long as achieving this goal does not increase your risk for developing low blood glucose (or blood sugar), otherwise known as hypoglycemia. The best way to determine your target A1C is to speak with your healthcare provider.

The higher your A1C, the greater your risk for developing complications, such as heart attacks, strokes, kidney disease, and neuropathy and circulation problems. To help lower your risk for diabetes complications, keep your blood glucose levels in your target range by self-monitoring and making adjustments with medicine (insulin, pills, or both), meal planning, and scheduled physical activity.

This article appears courtesy of Everyday

Do you need help managing your diabetes? Learn more about the Adult Clinic at Joslin Diabetes Center.

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  1. I have an anemia called spherocytosis where some of my red blood cells are spherical and are falsely considered defective by my spleen and removed prematurely. For five years my A1C levels have been below or slightly above 6. I was told I was pre diabetic. It would occur to me that an A1C would not be an effective measurement of diabetes with someone with spherocytosis.

  2. Dear ms Jo Anne M Rizotto,,

    Your article at the outset claims to be ABC of oA1C. and obviously gives out details which are seen in many other clinical sites and generally known to diabetics. However I am interested to get some clarifications on the subject from you, being an expert dietician and very actively doing research on the subject.

    1. You have indicated that that maintaining a value of 7 i s a good indicator of being safe from the bad effects of diabetes.. Here I may kindly be enlightened whether whether this indicator takes into account occassional spikes in blood sugar values despite AIC being within safe limits.
    2. I remember to have read some article that the AIC values measured in all clincal laboratories need not be often accurate. Are there specific guidelines universally accepted for finding out the A!C values.

    3. Are those who get A1C values lower than 6 susceptible to hypoglycemia.



  3. Dear Jo-Anne,
    In Sep 01/2014 the doctor informed me that I am prediabetic (HbA1c was 6.3) whereby I was administered glucophage 500XR once a day. After 4 months and with complete change in my life style, being more active, change in my diet, the results of the HbA1c was 5.71. I recently checked again and the results were 6.2.
    Appreciate it if you can tell me what is the best way/methods to avoid diabetes?

    Thank you,
    Abdulnasser Bahrami

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