Do you have to fast for the hemoglobin A1C test?

Many people wonder about fasting before a hemoglobin A1C (HbA1C) test. In most cases, you won’t need to fast before taking the test. HbA1C blood tests can be done on a full stomach at any time of the day. If your doctor is administering other tests within the same day as your HbA1C test, such as the fasting plasma glucose (FPG) test and the oral glucose tolerance test (OGTT) to diagnose type 2 diabetes and prediabetes, you may be asked to fast before coming in. Always check with your healthcare team before your appointment to find out how to prepare for your test.

LBL-1000864 Rev001

LBL-1000864 Rev001

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