Puzzled....

[Gudrun]

I am new to the forum, prediabetic, and have been low carbing for 17 days now (with medium fat). My fasting blood sugar has gone down nicely and fell by an average of 0.9 (from an average of 6.22 in March to an average of 5.32 since low carbing). So far, so good...

I also bought myself a Codefree meter and have been checking my blood, same drop (and comparing results with AccuChek (A and C below)). Again, so far, so good. The results were fairly similar:

18.4.2014 - 5.2 (A) 5.2 (C)
19.4.2014 - 4.6 (A) 4.4 (C)
20.4.2014 - 5.0 (A) 4.7 (C)
21.4.2014 - 5.5 (A) 5.6 (C)
22.4.2014 - 5.6 (A) 5.0 (C)

Then, this morning the results varied greatly: AccuChek read 6.7 whilst Codefree measured 4.7.

That is a huge discrepancy and one that worries me slightly. I will check again in a couple of hours and see whether it has normalized.

The only difference in food I had was yesterday. I have read (and advised new members) to eat and measure, eat and measure (ad infinitum) until they know what spikes their blood so they can avoid it or at least not have it often. Yesterday I decided to do this myself and had four biscuits (the first since low carbing). I had some hazelnut and cranberry biscuit dough in the freezer I made a few weeks ago. Baked them, eat 4 (133 g) and measured hourly afterwards.

on waking at 08:10 AccuChek 5.6 Codefree 5.0
(8:50am) 4 hazelnut and cranberry biscuits (133g)
After 1 hour AccuChek 8.7 Codefree 8.3
After 2 hours AccuChek 7.0 Codefree 6.2
After 3 hours AccuChek 5.5 Codefree 6.2
After 4 hours AccuChek 5.8 Codefree 5.5

The readings were far lower than I had expected (although I'm back on low carb again today and won't make eating biscuits a regular event).

So, really I have two puzzling questions this morning... The first is why there is such a big discrepancy between this morning's reading and the second, why isn't there a bigger jump in blood glucose after eating biscuits (not that I'm complaining).

 

[Andy12345]

hi, I'm going to speak very unscientifically, it seems to me that when you've been eating the right things you have effectively given your internal bits (dunno if its your pancreas insulin producing cells or your resistance to the insulin) a holiday and they are feeling revived and ready for a workout, or put your pre diabetes into remission, the problem is, if you continued to eat the biscuits it would soon go back the wrong way and you would quickly be back to square one, so in my opinion, the occasional thing won't hurt as long as it is occasional, this is just my uneducated take on it

the meter differences I've heard about before, all meters have a % of inaccuracy, so if one meter is being say 10% inaccurate downwards and the other upwards there would be a big difference between them, i can get very different readings from the same meter, from the same hole, 30 seconds apart, no idea why but i think we should take our readings on a longer term and use it as a way to monitor trends or big spikes, if i used two different meters and one was consistently higher than the other, thats the one i would use, because if its wrong id rather be working on the worse case scenario

again only my opinion, I'm afraid i don't understand the science behind like others do

 

[this is too difficult]

I have found that if the blood drop is not big enough the result can be inaccurate.

 

[sammey90]

The nurse at the hospital explained to us that the meter measures the sugar attached to the blood cells, and sometimes you can get an 'extra sugary' one, even out of the same drop!

Sent from the Diabetes Forum App

 

[Gudrun]

hi, I'm going to speak very unscientifically, it seems to me that when you've been eating the right things you have effectively given your internal bits (dunno if its your pancreas insulin producing cells or your resistance to the insulin) a holiday and they are feeling revived and ready for a workout, or put your pre diabetes into remission, the problem is, if you continued to eat the biscuits it would soon go back the wrong way and you would quickly be back to square one, so in my opinion, the occasional thing won't hurt as long as it is occasional, this is just my uneducated take on it

the meter differences I've heard about before, all meters have a % of inaccuracy, so if one meter is being say 10% inaccurate downwards and the other upwards there would be a big difference between them, i can get very different readings from the same meter, from the same hole, 30 seconds apart, no idea why but i think we should take our readings on a longer term and use it as a way to monitor trends or big spikes, if i used two different meters and one was consistently higher than the other, thats the one i would use, because if its wrong id rather be working on the worse case scenario

again only my opinion, I'm afraid i don't understand the science behind like others do

Thanks, Andy. I have just checked my blood again (after a coffee with semi-skimmed milk, which doesn't usually bother the results, no breakfast yet). AccuChek measures 7.0 and Codefree 5.6.

The idea of the pancreas having had a 'holiday' does make sense to me. Also the thought that it may now revolt against yesterday's biscuits and showing me results that I haven't had since low carbing 17 days ago.

The drop of blood I use is always big enough for several readings, really. I make sure I squeeze the finger enough to have a bit spare rather than not enough.

Must keep an eye on this, but no biscuits for a long while. Pancreas is back on holiday again.

 

[Gudrun]

The nurse at the hospital explained to us that the meter measures the sugar attached to the blood cells, and sometimes you can get an 'extra sugary' one, even out of the same drop!

Sent from the Diabetes Forum App

Thanks, Sammey, that's news to me. I'll keep an eye on things.

 

[Andy12345]

ive also read, that your supposed to pull to get the blood rather than squeeze as this does something to the blood, on saying that i always squeeze there has been threads it, ill try and find one

 

[aqualung]

I only use the codefree monitor so have nothing to compare it with. I too had a strange reading yesterday - 5.3 2 1/2 hours after eating pizza. It was a Lidl pizza though so not much dough!

I do struggle to get enough blood and only one finger seems to work so I have one very bruised finger. I have also had a few error messages as there is not enough blood

gudrun I am as confused as you!

 

[this is too difficult]

I only use the codefree monitor so have nothing to compare it with. I too had a strange reading yesterday - 5.3 2 1/2 hours after eating pizza. It was a Lidl pizza though so not much dough!

I do struggle to get enough blood and only one finger seems to work so I have one very bruised finger. I have also had a few error messages as there is not enough blood

gudrun I am as confused as you!

have you tried letting your hand hang down for a while before testing?

 

[aqualung]

have you tried letting your hand hang down for a while before testing?

I haven't but I will give it a go - thanks!

 

[this is too difficult]

Thanks, Andy. I have just checked my blood again (after a coffee with semi-skimmed milk, which doesn't usually bother the results, no breakfast yet). AccuChek measures 7.0 and Codefree 5.6.

The idea of the pancreas having had a 'holiday' does make sense to me. Also the thought that it may now revolt against yesterday's biscuits and showing me results that I haven't had since low carbing 17 days ago.

The drop of blood I use is always big enough for several readings, really. I make sure I squeeze the finger enough to have a bit spare rather than not enough.

Must keep an eye on this, but no biscuits for a long while. Pancreas is back on holiday again.

Apparently you should not squeeze your finger. You should stroke it down from your hand. No idea why though.

 

[Gudrun]

I know we shouldn't squeeze the fingers, but I have thick skin and unless I squeeze it, nothing comes out. But that is why I always make sure I have a big drop of blood to test from, so that whatever else comes out with the blood (and I remember reading about that somewhere, too), is kind of diluted.

 

[sanguine]

Is there a way to make up a 'standard solution' of sugar equivalent to, say, 6 mmol/L? It may not help much in a meter that is less than completely accurate but it could give some reassurance.

 

[Gudrun]

Is there a way to make up a 'standard solution' of sugar equivalent to, say, 6 mmol/L? It may not help much in a meter that is less than completely accurate but it could give some reassurance.

that's a good idea, Sanguine. Does anybody know how to do it?

 

[daisymoomoo]

The test solution which comes with your meter should be able to tell you if the meter is calibrated right.


Sent from the Diabetes Forum App

 

[smidge]

Ok, here goes:

1. Meters can read up to 20% inaccurate. Annoying for you Type 2s, deadly for us Type 1s. Use 1 meter and don't try to compare them - you'll drive yourself mad. They are good enough to get a trend to base choices on. Not good enough to base insulin doses on IMO, but they're all we've got.

2. Wash your hands with soap and warm water before testing - if you don't, be suspicious of the result as it will be contaminated to some extent.

3. Don't squeeze your finger - you'll get other bodily fluids in the sample and get inaccurate results. Hold your hand pointing down, gently massage your finger and then use gentle pressure to push the pad of your finger towards the pin hole. Warm fingers are easier to get blood from, hence wash them in warm water.

4. Meters are more accurate within normal ranges and are less accurate at higher and lower numbers. You will see more discrepancies as you head out of the 4.x to 7.x range, depending on the meter. To test their accuracy, use the manufacturers control solution - it will tell you if the meter is working within its tolerance.

5. Resting your pancreas might allow it to work more effectively, but I've seen no scientific evidence of this, only anecdotal.

6. Eating carby things in the evening could easily result in higher fasting levels. Eating them frequently will result in higher baseline BG. For those of us on insulin, we would need to raise our basal dose to deal with the higher baseline as well as our bolus dose for the food. Type 2s without insulin would simply see their baseline rising and therefore they would find it harder to get good post meal levels as they had a higher starting point. It would generally result in higher HbA1c and more meds.

Smidge

 

[jack412]

the spec of +/- 20% is with using the same meter and the same bottle of strips
as well as the difference between meters. If your really want to frustrate yourself, use 3 strips of either meter one after the other and see the difference
I use acuchek and there is an error rate and I forget out the decimal point and work in halfs, to me it's about 6 or about 6 and a half or about 7,
with the occasional wild one that I throw away and retest because the number has to be wrong

 

[sanguine]

The test solution which comes with your meter should be able to tell you if the meter is calibrated right.

My HD Codefree only comes with a test strip to prove that it is working (displays 'OK'), not a test solution.

 

[sanguine]

the spec of +/- 20% is with using the same meter and the same bottle of strips
as well as the difference between meters. If your really want to frustrate yourself, use 3 strips of either meter one after the other and see the difference
I use acuchek and there is an error rate and I forget out the decimal point and work in halfs, to me it's about 6 or about 6 and a half or about 7,
with the occasional wild one that I throw away and retest because the number has to be wrong

But if it's +/- 20% that means an apparent reading of 6 could be anywhere between 5.8 and 7.2. I don't recall any statement of accuracy in the HD Codefree instructions, but if that's what it is I'm not surprised!

 

[jack412]

But if it's +/- 20% that means an apparent reading of 6 could be anywhere between 5.8 and 7.2. I don't recall any statement of accuracy in the HD Codefree instructions, but if that's what it is I'm not surprised!

yep that is the spec. anything between 5.8 and 7.2 for I think 95% of the strips, is a pass. or roughly 6-7
I found acuchek about 10% most of the time and which is why I work in halfs , code free may be similar
I don't endorse acuchek, it was that weeks free meter, the strip here are discounted and all the same price regardless of brand