A1C Test and the Estimated Average Glucose (eAG)
What does the A1C test measure?
The A1C test (Glycosylated Hemoglobin or
Hemoglobin A1C) measures the average amount
of sugar attached to the hemoglobin part of your
red blood cells.
When and how is the A1C test done?
The A1C test is a blood test that may be done as
often as every 3 months since this is the lifespan
of a red blood cell. Most often the test is done
every 3-6 months or yearly. Your insurance or
Medicare may have specific guidelines for how
often the A1C test can be done. The test does not
Why is the A1C done?
Research shows that keeping blood sugar levels
close to normal can greatly reduce the chance of
problems related to diabetes. Any decrease in
A1C will help to reduce the long term problems
from diabetes. One large study showed that
keeping the A1C below 7% lowered the risk of
ξ Retinopathy (eye damage) lowered by 76%
ξ Nephropathy (kidney disease) lowered by
ξ Neuropathy (nerve problems) lowered by 60%
What do the A1C results mean?
The A1C measures your average blood sugar 24
hours a day, 7 days a week, for 2-3 months. The
A1C value is given as a percentage. It may be
more helpful to translate this A1C value into an
average glucose value. This is called the
estimated Average Glucose or eAG. The eAG
uses the same values and units (mg/dL) that you
see when you check your blood sugar with your
meter or get a report from the lab. This may help
you to see how your daily blood sugar checks
relate to your A1C.
This chart shows how your A1C value relates to
estimated Average Glucose (eAG). For example,
an A1C of 7% is equal to an eAG of 154 mg/dL.
You and your diabetes care team will decide on
your A1C goal.
15 - 17 % 384 - 441
14 % 355
13 % 326
12 % 298
11 % 269
10 % 240
9 % 212
8 % 183
Goal 7 % 154
diagnosed at this
6.5 % 140
diagnosed at this
5.7 - 6.4 % 117-137
Keep a record of your A1C and eAG results.
Compare your results to other recent values and
your goal range. Talk with your health care team
about your A1C test results. Results may suggest
that you need to adjust your diet, activity, or
medicines. The goal is to keep A1C levels as
close to normal as possible without frequent low
My A1C goal is _____% eAG ____ mg/dL
Date of Results A1C eAG
Your health care team may have given you this information as part of your care. If so, please use it and call if you have any
questions. If this information was not given to you as part of your care, please check with your doctor. This is not medical
advice. This is not to be used for diagnosis or treatment of any medical condition. Because each person’s health needs are
different, you should talk with your doctor or others on your health care team when using this information. If you have an
emergency, please call 911. Copyright © 1/2016 University of Wisconsin Hospitals and Clinics Authority. All rights reserved.
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