Some bodies don't follow the rules
Type 1 Diabetics quickly learn about the Glycated Hemoglobin value, or HbA1c, that can be obtained from a laboratory blood test. It refers to the percentage of hemoglobin in the blood that is affected by blood sugar. Because red blood cells are replenished about once every 90 days, this laboratory test is an indication of average blood sugar control over the past three months.
T1D children are encouraged to achieve HbA1c levels at or below 7.5%. Adults are encouraged to achieve 7.0% or better.
I've only had a HbA1c test result as low as 7.0% once in the last sixteen years since my Diabetes diagnosis and this has been an ongoing frustration for me.
It's easy to find a chart that shows what average blood sugar levels correspond to the HbA1c percentages. For example, this one comes from the Mayo Clinic:
My last HbA1c test resulted in 7.4%, so you'd expect my average blood sugar levels to be in the neighborhood of maybe 165 mg/dL.
Below is a chart, provided by the open source Nightscout software, showing my average blood sugar levels measured by my Dexcom G4 continuous glucose monitor over the last three months, broken down by week:
Where are those ~165 mg/dL averages?
Sometimes I think my body is just trying to screw me over! My HbA1c is supposed to be around 6.3%!