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Type 2 How come blood prick tests can change within minutes?

MKD75

MKD75

Well-Known Member
Messages
156
Type of diabetes
Type 2
Treatment type
Diet only
I was wondering how you can test you blood and it be 1 reading and test immediately after and it the different? Same machine, different finger?

Had a great night tonight.. mean out, burger and chips and a few gins with diet ginger ale. Tested blood and it was 15!! Never been that high then 10 seconds later on a different finger it was 12.5.. still high but not 15?

Why does it change so quickly? What’s accurate?
 
These machines have a margin of error - I believe, although I may be corrected, that it is 15%. So with your reading of 15, that actually means it was probably somewhere between 12.7 and 17.3. The 12.5 could have been anywhere between 10.6 and 14.4. So the 'true' reading was somewhere in the overlap.

Obviously, the bigger the number, the bigger that margin of error is going to be.
 
EllsKBells said:
These machines have a margin of error - I believe, although I may be corrected, that it is 15%. So with your reading of 15, that actually means it was probably somewhere between 12.7 and 17.3. The 12.5 could have been anywhere between 10.6 and 14.4. So the 'true' reading was somewhere in the overlap.

Obviously, the bigger the number, the bigger that margin of error is going to be.
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Ahhh really?! I was unaware of that! Thank you x
 
MKD75 said:
Why does it change so quickly? What’s accurate?
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Why do you expect it to be the same? Blood sugar is constantly changing - it is never static.

Glucose in blood isn't evenly distributed around the whole of your incredibly complicated bloodstream plumbing system, so there is no surprise at all that you're getting different readings.

Both of your readings are in the same sort of range - too f'ing high - so the numerical difference makes no odds.

Your bloodstream moves glucose around your body in the same way that road networks move traffic around - sometimes there'll be more traffic/glucose in rush hour/post meal at 5:30 pm, than there will be at 2:00 am on a quiet backroad.

The art of both T1 and T2 is to figure out how to find those quiet little backroads to keep at a steady pace without getting snarled up in heavy traffic/high bg.
 
Scott-C said:
Why do you expect it to be the same? Blood sugar is constantly changing - it is never static.

Glucose in blood isn't evenly distributed around the whole of your incredibly complicated bloodstream plumbing system, so there is no surprise at all that you're getting different readings.

Both of your readings are in the same sort of range - too f'ing high - so the numerical difference makes no odds.

Your bloodstream moves glucose around your body in the same way that road networks move traffic around - sometimes there'll be more traffic/glucose in rush hour/post meal at 5:30 pm, than there will be at 2:00 am on a quiet backroad.

The art of both T1 and T2 is to figure out how to find those quiet little backroads to keep at a steady pace without getting snarled up in heavy traffic/high bg.
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I didn’t know why it wouldn’t be the same hence the question? Had I have known the answer I wouldn’t have asked and your right.. both are too f**ing high but after weeks of no carbs and no alcohol and no doing f**all, I need a blow out.. high readings or not. Does everyone one this forum literally follow LCHF 247, 365 days a year? If so please tell me how you all manage it without a monthly blow out/naughty night?
 
of course we do we are after all perfect now pass the chocolate and stop worrying. you knew it was going to go silly just wait until tomorrow it should be down again. if you reading ws really 15 then a working meter will read somewhere between 13-17 you will never get 2 the same readings. did you wash your hands.
 
paulus1 said:
of course we do we are after all perfect now pass the chocolate and stop worrying. you knew it was going to go silly just wait until tomorrow it should be down again. if you reading ws really 15 then a working meter will read somewhere between 13-17 you will never get 2 the same readings. did you wash your hands.
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No I didn’t actually and I’m now out of test strips and can’t test again I do this every month or 2. Have a a few drinks (sugar free mixers!) and a meal of my choice and feel guilty as hell and annoyed with myself for doing so. I manage on diet alone T2 and a1c last week was 48 and never been over 51 so know I’m not in a terrible situation but it just pee’s me off sometimes.. anymore got a new and pancreas they don’t want as mines on the way out ??
 
35534ec1e28fc047f4d1c185bfb1bdee.jpg
I did a test with 3 meters all from same blood sample no machine is accurate. No blood sample will be the same as the next it's all about finding an average and working with it.
 
JohnEGreen said:
No where near as silly as the meal I had tonight remember tomorrow is another day.
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Thank you. A non sarcastic/judgmental answer!! Nice to know you are also human lol. I will be back to The the boring carb free diet tomorrow and feeling hungry and exercising.. I’m intrigued? What was your meal?
 
Dabe said:
35534ec1e28fc047f4d1c185bfb1bdee.jpg
I did a test with 3 meters all from same blood sample no machine is accurate. No blood sample will be the same as the next it's all about finding an average and working with

Ah interesting!! Glad I have no more strips left today.. I’d be testing all night else. Dying to know what my level it now though.
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oddly i was not being sarcastic. we all do it we are all human. its only if your doing it everyday that will be an issues. so lose the guilt. its your body and if you want a burger have one. just have more lettuce. lots and lots of the bunny food.
 
Back to the original question why readings from different fingers can be different when only taken minutes apart...
In addition to the accuracy of the meter, it may also be due to some residue of something sugary you had on your first finger.
 
I also find with the Meters that I have had it also depends on the amount of Blood your put on the strip, You can put a small drop of blood on and it will still accept the reading, I use the Freestyle Libre and the reading can in fact change by around 0.50 units within seconds due to the amount of blood on the strip.
 
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