The Saturday Share #9
So to do my part in trying to keep internet health information correct I’ve been two-timing my blog by writing over at Sharecare were I am one of their “Experts” answering diabetes questions posted by readers.
I’m having a blast, and I’ve decided that every week I’m going to share one of my favorite questions with you here.
Sharecare Question: Why is my A1C high when my blood glucose levels are in my target range?
My “Expert” answer: I want you to picture a freshly fried doughnut hole, just out of the deep fryer. Steam wafts from its surface. Still gleaming wet with oil, it’s sent spinning across a tray of powdered sugar. As it tumbles, sugar sticks to the wet oil, coating it, covering it as it rolls and bounces along.
Well, the same thing happens to your red blood cells. As they tumble and spin and roll through your blood vessels, sugar molecules stick to their skins. Or another way to think of it is to picture a windshield of a truck after driving through a swarm of mosquitoes. Splat-Splat-Splat-Splat-Splat! (OK, I just threw that in so you wouldn’t log off and drive straight to Dunkin Doughnuts.)
So an A1C test is a measure of how much of the skins of your red blood cells are splattered with sugar, which in turn gives as a picture of the blood sugar environment in which the cells lived, which in turn gives us a notion of your average blood sugar over the last several months.
So the A1C test looks at average blood sugar, while your fingersticks look at moments in time. The most common cause of a difference between A1C and fingersticks is that the fingersticks are not frequent enough, or are not at the right times to catch the elevated blood sugars that are jacking your A1C to higher levels.
For instance, if you are only testing in the morning, you are missing possible elevations after meals or overnight while you are sleeping. The A1C test is not perfect. For instance, if your sugar was ranging scary low to scary high you might get a number that looked pretty good. That said, most “false reads” are good looking numbers that mask troublesome variability. Additionally, if you are anemic, you can also get a false low, as your blood cells don’t last as long as typical.
But if your A1C is high, there are some high blood sugars lurking somewhere. And that is exactly why we do both fingerstick testing a A1Cs. They serve as checks and balances against each other.
You can check out other Expert’s answers to this question, and my answers to many more questions by going here:
Then select the “Answers” tab near the top left.