Variance in blood sugar reading on both hands using the meter

I’m just curious. Today I measured my BG on my left hand, got 7mmol (126mg). Then tried again using my right hand and got 7.6 mmol (136mg). Then went back to my left hand and used another finger, got 7.3mmol (131mg). Not sure whether there is something wrong with my meter or whether the blood saturation is uneven generally around the body. Is this normal?

I wanted to calibrate because my sensor was showing 9.5 (171mg) so I ended up going for 7.3mmol since it was on the same arm the sensor was on.

Totally normal, all of those readings are well within the variation allowed on finger stick meters. They are allowed to be 20% off just like the Dexcom so you could have gone eny, meany, miny, mo. If I am suspicious of my BG meters reading I will either wash my hands or use an alcohol swab and do 2 tests from the same finger stick (in other words: from the same drop of blood) so they are as close as it is possible to be.


Wow, that would influence the accuracy of a calibration on a sensor quite a bit!

If you are talking dexcom it is only a temporary adjustment when you calibrate. Then it readjusts back to its original factory calibration.
That’s why calibrating them is a waste if time.
So if it’s way off you can restart it with no code and calibrate it twice a day.
Or give up on it cause once it’s bad it’s just always bad.
Dexcom is good about replacing.
I usually only test one time when I first start getting data. Then if it doesn’t feel right. Like I feel high but it reads normal.
I used to do finger sticks 6 times a day on Medtronic.
Now maybe 3 times in 10 days on g6 dexcom.
I find it’s generally very close to my meter most of the time.
Only time I see it off is when very low.

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I’ve gotten different readings when testing twice from the same finger stick! Who knows.

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Yep, if your BG meter isn’t accurate then you can really mess up the calibration. I don’t know weather or not calibrating helps in the long term but I do find that I sometimes need to bully a sensor into accuracy the first day of a session. Once it’s settled down I rarely need to do any more calibrations for the rest of the session.

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