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Why You Need an A1c Test If You Have Diabetes

The hemoglobin A1c test is a simple blood test that checks how much sugar, or glucose, is stuck to your red blood cells. This test also is called the glycohemoglobin test or the A1c test. Most doctors think the A1c test is the best way to monitor your diabetes over the long term.

What does your A1c result mean?

Your test results tell you how well you have controlled your diabetes over the past three months. With this information, your doctor can adjust your medicine and diabetes treatment, if necessary.

This test also gives you an idea of how likely you are to develop problems such as kidney failure, vision trouble, or numbness in your leg or foot. Keeping your A1c level in your target range can lower your chance for problems.

The test result is usually given as a percentage.

The American Diabetes Association (ADA) recommends that most non-pregnant adults with diabetes have an A1c level less than 7%. If your A1c level is higher than your target A1c level, the ADA recommends that your doctor look at making changes in your diabetes treatment.

To lower your A1c level, your blood sugar needs to be lower. In some people with diabetes, having blood sugar that is too low may cause problems. Your doctor can help you decide the best and safest A1c level.

How often should you have your A1c tested?

If you have diabetes, your doctor may order a test every three to six months, depending on your type of diabetes and how well you control it. Generally, A1c is checked two to four times a year. Talk with your doctor about how often you should expect to have this test. If your levels have been good for several tests, you may not need the test as often.

Do you need to fast before your A1c test?

You do not need to fast before this test. You can have this test at any time during the day, even after a meal.

Why do you need the A1c test?

When you check your blood sugar at home, you are checking its level at that moment. This level may change because of what you eat, how much you exercise, or the medicines you take.

Checking your blood sugar at home helps you manage your daily diabetes care. It helps you decide if you need to eat something or use your insulin, for example.

The A1c test gives you your average blood sugar level over the three months before the test. The result does not change because of food, exercise, or medicine. It helps you with your long-term diabetes care. If your A1c is high but the results you see when you check your blood sugar are in the target range, this usually means you will need to start checking at other times of the day, such as after meals. 

The A1c test helps your doctor decide if your medicine or overall treatment plan needs to change. 

The A1c test does not replace daily blood sugar testing, but it provides useful information. 

The information contained in this article is for informational purposes only, and does not constitute medical advice, diagnosis or treatment.

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