• Guest - w'd love to know what you think about the forum! Take the 2025 Survey »

A1C freestyle libre

Ovi

Member
Messages
21
For libre users. How big of a difference was between your A1C on your libre and the blood test? I just has my result and there was a big difference between them. My libre lacked some data over the last 3 months(around 2-3 weeks) which I assume will affect the accuracy.
 
My "estimated hba1c" on Libre was 10 lower than my real one.
I concluded it was another number to track rather than something to compare with the blood test.
 
My Libre always predicts my hba1c to be 8 mmol/mol lower than a lab test. Has consistently done so for the past 5 years so I still have a very good idea of what my hba1c will be when looking at my Libre.
 
I used the original Libre for a while, and its predicted HbA1c was always consistently lower than my actual test result.. And the prediction from my meter was mid way between those 2, but all their patterns and trends matched well enough for me to know what my actual Hba1c would be
 
Your Libre is taking all of your data and working out what the average levels have been, so in reality a true average.
I know everyone calls the HbA1c an average of your blood sugar over the last 12 weeks, but of course it is not really an average at all.
The HbA1c is measuring glycated haemoglobin, the higher your blood sugar has been over the lifetime of your blood cells, the higher your HbA1c will be. Blood cells usually live for around 12 weeks which is why they call it a 12 week average.
But how long do your blood cells actually last, 11 weeks, 10, or maybe 13? Who knows. I could have the same HbA1c as you but if my cells kick the bucket at 10 weeks and yours hang around for 13, my blood sugar will have been much higher than yours for us to have the same HbA1c.
So HbA1c is a useful tool to for Dr's to diagnose and assess our progress.
Your Libre is giving a true mathematical average worked out from your glucose levels.
If the two numbers were to match, it would just mean that your blood cells are behaving themselves and turning up their toes on their 12 week birthday.
 
My HbA1c on my libre is 5 less than my lab blood test
 
And actually that’s the same for me. They may occasionally match very closely but generally the Libre reads 1mmol lower. Certainly it never reads higher than a fingerprick. So that tbf would more or less account for the discrepancy in my case.
 
Cookies are required to use this site. You must accept them to continue using the site. Learn More.…