Red blood cells and the hemoglobin they contain have an average life span of 120 days during which glucose molecules are exposed to the red blood cells and form glycated hemoglobin. Therefore, in theory, changes in your A1C levels won’t be apparent for at least the 120 days it takes for the affected red blood cells to complete a life cycle.
The amount of time it takes to lower your A1C depends on how big of a change you are trying to achieve. If your A1C is in the double digits, it may take a matter of 2 or 3 months to see a significant change if your diabetes management is consistent and tight. If your A1C is a point or two away from ADA/AACE recommendations, getting to goal may take a little longer.
“Lowering your HbA1c from a [high] number to an 8.0 or 7.5 is much easier than lowering it from a 7.5 to 6.5,” said dLife Expert CDE Claire Blum in response to a question about lowering A1C levels. “Tightening of control that occurs at the lower numbers takes a lot of fine tuning. Our bodies also require some time to adapt to the change of improved [levels].”
There are no special tricks to getting your A1C to a level more acceptable to you and your doctor. Lowering your A1C is doing just what your doctor has always told you was best for good diabetes management.