Final answer:
Hemoglobin A1c is measured to monitor the long-term control of diabetes mellitus. Keeping the levels close to 7% helps in delaying or preventing diabetes complications.
Step-by-step explanation:
Hemoglobin A1c is measured to monitor the long-term control of diabetes mellitus. The level of hemoglobin A1c reflects the average blood glucose level over the past 4 months, as the glucose stays attached to hemoglobin for the life of the red blood cell. Diabetics who keep their hemoglobin A1c levels close to 7% have a much better chance of delaying or preventing diabetes complications. Lowering the level of hemoglobin A1c by any amount improves a person's chances of staying healthy.