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Type 2s: What was your fasting blood glucose in a morning? (very low chat level)

Andydragon said:
Or your meter is under reading. What is the margin of error on a libre? It’s about 15% on a meter isn’t it? Still take the average is about 6.5 which is good
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Given 15% tolerance on the blood test and 20% on the Libre, it's quite possible the true reading is somewhere between the two, or even above or below both. I've seen the finger prick swing both ways, giving a fairly small window of overlap between the lowest reading +15% and the highest reading -15%, so it does seem it can swing either way. Even the Libre documentation basically tells you to trust a blood test over the Libre. Since the Libre doesn't test blood directly (and relies on a correlation between blood and interstitial fluid) I suppose that makes sense.

The trends on the Libre are probably more interesting than the actual figures. I've noticed that light exercise (leisurely pedalling my e-bike) can spike me as badly as carby foods, but more intense exercise (working up to 160bpm heart rate on my exercise bike) doesn't. So anything with carbs (even low numbers) before a bike ride is a bad idea if I'm trying to stay in single figures.
 
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