U.S. Department of Health and Human Services

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Know Your Blood Sugar Numbers

If you have diabetes, keeping your blood sugar (glucose) numbers in your target range can help you feel good today and stay healthy in the future.

There are two ways to measure blood sugar.

  1. The A1C is a lab test that measures your average blood sugar level over the last 2 to 3 months. It shows whether your blood sugar stayed close to your target range most of the time, or was too high or too low.
  2. Self-tests are the blood sugar checks you do yourself. They show what your blood sugar is at the time you test.

Both ways help you and your health care team to get a picture of how your diabetes care plan is working.

About the A1C test

Why should I have an A1C test?
The A1C tells you and your health care team how well your diabetes care plan worked over the last 2 to 3 months. It also helps decide the type and amount of diabetes medicine you need.

What is a good A1C target for me?
For many people with diabetes, the A1C target is below 7. You and your health care team will decide on an A1C target that is right for you.

If your A1C stays too high, it may increase your chances of having eye, kidney, nerve, and heart problems.

How often do I need an A1C?
You need an A1C at least twice a year. You need it more often if it is too high, if your diabetes treatment changes, or if you plan to become pregnant.

What if I plan to become pregnant?
Talk with your doctor before you get pregnant. Your doctor can help you reach an A1C target that allows a healthy baby to develop. If you are already pregnant, see your doctor right away.

About self-tests for blood sugar

Why should I do self-tests?
Self-tests can help you learn how being active, having stress, taking medicine and eating food can make your blood sugar go up or down. They give you the facts you need to make wise choices as you go through the day.

Keep a record of your results. Look for times when your blood sugar is often too high or too low. Talk about your results with your health care team at each visit. Ask what you can do when your sugar is out of your target range.

How do I check my blood sugar?
Blood sugar meters use a small drop of blood to tell you how much sugar is in your blood at that moment. Ask your health care team how to get the supplies you need. They will also show you how to use them.

What is a good target range for my self-tests?
Many people with diabetes aim to keep their blood sugar between 70 and 130 before meals. About 2 hours after a meal starts, they aim for less than 180. Your target ranges may be different if you are an older adult (over 65), have other health problems like heart disease, or your blood sugar often gets too low. Talk with your health care team about the best target range for you.

Can my blood sugar get too low?
Yes it can. If you feel shaky, sweaty, or hungry, do a check to see if it is below your target range.

Carry something sweet with you at all times, such as 4 hard candies or glucose tablets. If your blood sugar is too low, eat the candy or glucose tablets right away. Let your health care team know if this happens often. Ask how you can prevent it.

How often should I check my blood sugar?
Self-tests are often done before meals, after meals, and at bedtime. People who take insulin need to check more than those who do not take insulin. Discuss your self-test schedule with your health care team.

Are there other numbers I need to know?
Yes, you need tests of your blood pressure and cholesterol (a blood fat). You and your health care team need to decide the best targets for these too. Keeping them in your target range can help lower your chances for having a heart attack or stroke.

How do I pay for these tests?
Medicare and most insurance pay for the A1C, cholesterol, and some self-test supplies. Check with your insurance plan or ask your health care team for help. For more on Medicare visit www.medicare.gov/health/diabetes.asp.

What is in it for me?
Finding the time to check your blood sugar can be a struggle. It is also hard when your sugar levels do not seem to match your efforts to manage your diabetes. Keep in mind that your self-test and A1C results are numbers to help you, not to judge you. Many people find that self-testing and using the results to manage their diabetes pays off. They are more able to take charge of their diabe-tes so that they can feel good today and stay healthy in the future.

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John visits his health care team

John and his health care team use all of his test results to get a picture of how his diabetes care plan is working.

At each visit John and his team:

  • Look at his A1C, blood sugar self-test record, cholesterol, and blood pressure results.
  • Check to see if he is reaching all his targets.

At his visit today, John’s A1C is too high. He and his health care team talk about what he can do to get closer to his target A1C.

Together they decide that John will:

  • Increase his walking time to 30 minutes every day after dinner.
  • Self-test at bedtime to see if being more active lowers his blood sugar.
  • Call his doctor in 1 month for a change in medicine if his self-tests are still out of his target range.

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Last reviewed: 07/01/2014