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This information was reviewed and approved by Dthia Kalkwarf (1/1/2014).

The Hemoglobin A1c test tells the doctor and patient the average blood sugar level over the last 3 months.

A person without diabetes

A1c less than or equal to 5.6%


A1c 5.7 to 6.4%


A1C equal to or greater than 6.5%

Healthy level for a person with diabetes

A1c less than 7.0%


What Causes A1c Levels to be high?

High average blood sugars over the past 3 months may be from:

  • Weight gain
  • Too many carbohydrates from foods and drinks
  • Not getting enough exercise  
  • Not taking diabetes medicines as prescribed
  • Diabetes medicines need to be adjusted or changed
  • Illness
  • Stress
  • Addition of medications, i.e. prednisone


How Can My A1c Be Lowered to a Healthy Level?

  • Work with your health care team to achieve weight loss if that is a goal
  • Limit how many carbohydrates you eat and drink
  • Be physically active 30 – 60 minutes at least 5 days a week, such as brisk  walking
  • Take medications as prescribed by your doctor


Your A1c level should be drawn every 3 – 6 months to best understand your overall blood sugar control. Your diabetes educator(s) can help you to balance diet, encourage exercise, understand medications, and help you cope  with stress to improve your A1C level and manage your diabetes.

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