A1c is a specific subtype of hemoglobin (Hb), the compound in the red blood cells that transports oxygen. Glucose binds slowly to Hemoglobin A and decomposes slowly as well, so the HbA1c level in your blood is an indicator of the average blood glucose level of approximately the past 4 weeks.

What are good blood sugar levels?

Everyone has some sugar in their blood. The normal amount of sugar in the blood ranges from about 70 mg/dL to about 120 mg/dL in people who don't have diabetes. Blood sugar goes up after eating, but returns to the normal range in 1 or 2 hours. A good blood sugar range for most poeple with diabetes is from about 70 mg/dL to 150 mg/dL. This is before a meal - like before breakfast or 4 to 5 hours after you last meal. Your blood sugar should be less than 200 mg/dL about 2 hours after your last meal. The American Diabetes Association recommends an A1c of 7% or lower.