what is an A1C test
The A1C test is a blood test used to measure the average level of glucose in the blood over the last two to three months, and is used as a means of checking how well blood sugar levels are being controlled for a person with diabetes. The test is used for both monitoring and diagnosing diabetes, and results come from a blood sample given at the doctor's clinic. 2  It indicates the average blood glucose level over the two to three months leading up to the test, so it is a reliable indicator of glycemic control.