A glycosylated hemoglobin test (HbA1c) is a blood test that measures the amount of glycosylated hemoglobin in the blood. Hemoglobin is a protein found in the blood. Glycosylated hemoglobin means that glucose (sugar) has attached to the hemoglobin protein. The higher your blood sugar is, the more that glucose gets attached to your hemoglobin.

Glycohemoglobin
glucose and RBC
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HbA1c shows how high your blood sugar levels have been during the past three months. This can help your doctor determine how well you are controlling your diabetes. Your doctor may also use HbA1c to test you for diabetes.