HBA1C, also known as glycated hemoglobin, is the product of the combination of red blood cell hemoglobin and blood glucose. The process of hemoglobin glycation is an irreversible, slow, non-enzymatic reaction. Glycated hemoglobin reflects the average blood glucose concentration over the past 2 to 3 months, and this concentration is not affected by immediate blood glucose, with a normal range of 4% to 6%. Glycated hemoglobin can be used as an indicator of diabetes, and can be used by doctors to determine whether medication needs to be adjusted based on the results of the test to see how well a diabetic’s blood sugar is controlled. If abnormalities of glycosylated hemoglobin occur, it is recommended to go to the hospital.