An A1c test can be used to diagnose prediabetes or diabetes.
According to CDA guidelines:
A1C <5.5% Normal. 
A1C >5.5%, at risk of Prediabetes.
A1C 6.0%-6.4%, Prediabetes.
A1C > or equal to 6.5%, Diabetes.
📍 Prediabetes refers to blood glucose levels that are higher than normal, but not yet high enough to be diagnosed as type 2 diabetes. Although not everyone with prediabetes will develop type 2 diabetes, many people will.
📍Ask your doctor what is your A1C level, and if it’s >5.5%, then it’s time to make some lifestyle changes!
📍A1c  (Hemoglobin A1C) is a blood test that checks the amount of sugar (glucose) bound to the hemoglobin in the red blood cells.
📍The A1c test result does not change with any recent changes in diet, exercise, or medicines.
📍Glucose binds to hemoglobin in red blood cells at a steady rate. Since red blood cells last 3 to 4 months, the A1c test shows how much glucose is in the plasma part of blood.
📍A1C shows how well your diabetes has been controlled in the last 2 to 3 months and whether your diabetes treatment plan needs to be changed.
📍The A1c test can also help your doctor see how big your risk is of developing problems from diabetes, such as kidney failure, vision problems, and leg or foot numbness.
📍Keeping your A1c level in your target range can lower your chance for medical problems.
📍Working with a registered dietitian can help you plan a healthy diet, improve your blood sugar control, lose weight if needed, prevent diabetes, or better manage your  diabetes.