Glycated Hemoglobin - HbA1c or A1c test is used as a guide to know what is your average blood glucose level during the past three months. Glucose tends to stick to red blood cells and more the glucose in the blood, the more the number of red cells that have glucose on its surface. Normally 4 to 6 red cells in 100 have glucose attached to its surface; hence the range of HbA1c in a normal person is 4 to 6%. Better control of glucose means lesser the complications of diabetes to your heart, blood vessels, kidneys, brain, nerves, eyes and feet. So do try and keep your sugars under control and live longer. It is all worth all your efforts.