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5.5 to 5.9 mmol/L Oddity

Klpville

Well-Known Member
Messages
97
Type of diabetes
Prediabetes
Treatment type
Diet only
Dislikes
I dislike all sorts of motors, engines, mechanics, and just any "rusty iron" in general.
Hello guys,

I have a tricky question. Your web-site (diabetes.co.uk) gives two charts that say the following:

1. NICE recommended target blood glucose level ranges: non-diabetic healthy individuals 4.0 to 5.9 mmol/L before meals.
2. Blood sugar levels in diagnosing diabetes: fasting (before meals) from 5.5 to 6.9 mmol/L is prediabetes.

Now if the level is 5.7 mmol/L before meals, what does that mean? I am healthy according to point 1 above. However, I have prediabetes according to point 2. Could anybody throw some light upon it, please? Many thanks!

P.S. Which range does 5.6 to 5.8 belong to?
 
I suggest that if you are concerned about your health you consult your doctor and request a HbA1c test this is the test used for diagnosing diabetes by doctors odd random finger prick test will not be definitive.
 
@Klpville agree that you should request tests from your doctor if you’re worried about diabetes.

Having said that, the ranges you mention are ranges and guides. Pre-meal readings are likely to fluctuate and on their own don’t give the whole picture in relation to diabetes.
 
Those pre-meal reading some are guidelines really. I feel pretty certain no diagnosis would be made on the strength of one or two higher than ideal levels - except when they get above something like 11.

In most instances, further tests are require to draw any conclusions, but if you have concerns, you GP is the man/woman to assess things, in conjunction with your medically and family histories.

Edited to remove auto-correct styleeeeee typo. No wonder I rarely use my iPad on here! Apologies, @Klpville if I added to your confusion.
 
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Welcome to the forum @Klpville. As the others have said, we cannot give you a diagnosis. One finger prick reading can be influenced by various factors and is only a snapshot of your blood glucose at that moment in time.
A 5.7 reading before eating isn't high and doesn't necessarily indicate pre-diabetes. Only a full HbA1c test which gives an average of your bg levels over the last 8-12 weeks can diagnose this condition.
 
Thank you so much everybody for replying so quickly! What a friendly bunch of people.

Well, I am still learning how to use this sugar/glucose meter of mine and I was looking for some guidance as all the charts and graphs found online have different readings for some reasons as per my example in my first message. It looks like there is no fixed value as to when it is considered to be diabetes. For example 5.5 mmol/L before meals / fasting is diabetes and everything below is not. It appears to be that this number is pretty much floating back and forth and it is very flexible. I wonder how do doctors diagnose it when there aren't any set terms and values.
 
They use the HbA1c results as a rule they are not quite so flexible but general rule set down is less than 40 mmol/mol is normal, . 42 to 49 mmol/mol is prediabetes , 50 mmol/mol and above would indicate diabetes.

At diagnosis mine was 64 mmol/mol

A bit confusing I know but do not confuse the measurements for HbA1c with your finger prick test though they sound similar they are not equivalent And the HbA1c is an average over time..

Edit to correct figures.
 
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Thank you so much for your input Prem51. I appreciate. Well, as far as I know almost any glucometers have daily, weekly, and monthly numbers and readings that accumulate over time and give you totals. All you have to do is to measure your glucose level regularly and then you will have these numbers for any period of time that you may need or configure your meter for. Am I not right? My "contour" shows daily, weekly, bi-weekly, and monthly readings with average, low, and high numbers clearly shown. The trick is to set your low and high numbers but... I am still unable to find any exact values to set for high/low as all the charts and graphs I found online give different readings... some say 5.5 is diabetes... others say 6.0 is perfectly healthy...
 
Klpville said:
some say 5.5 is diabetes... others say 6.0 is perfectly healthy...
Click to expand...

Do also note that meters only have to be accurate to within 15%, so for instance if your blood glucose level was 5, then the meter could show anything between 4.25 and 5.75 and still be considered as accurate, some seem to err on the higher side, some seem to err on the lower side, some may vary.
There is a nice graphic if you follow this link: https://mobile.twitter.com/Diabetescouk/status/342654280404189184 that shows what each HbA1c values translates to. The HbA1c (IFFC) value is the measurement that is used in the UK, the HbA1c(DCCT) is used in the US and was the old value used in the UK (though some UK docs still seem to use it despite the fact its kinda outdated now). The mg/dl is what the US uses for finger prick blood tests, the mmol/L is used in the UK for finger prick blood tests (this is the value your meter is returning) - the values for mmol/L (or mg/dl) in the grid I assume are what the average mmol/L (or mg/dl) would be for the specified HbA1c - though obviously averages often don't actually tell much of the story
 
Glucometers only record the bg at time of testing (which can be up to 15% off), not continuously. I could take my bg readings mid afternoon which would show a much lower 'average' reading over 7 days, 30 days or 90 days, than if the average was for readings taken in the morning or at night. They do not give you as accurate a figure as an HbA1c test. Though even better would be the continuous reading from a permanent monitor like a Libre monitor.
I think some countries have different definitions of what figure is 'diabetic'.
 
The NICE Target table shows what level different types of diabetics should aim for. Apart from diet, those taking drugs including insulin can have their dose adjusted to try to achieve the target, remembering there may be other factors and their target should be personalised by their health team. As it says the levels for non-diabetics is just for information, non-diabetics do not have a NICE target and of particular relevance to your question, the chart does not mention pre-diabetes or give a target.
The Diagnosis chart does mention pre-diabetes and this results in the apparent anomaly you mention. A reading of 5.7mmol/L means you are pre-diabetic which the NICE chart does not cover.
 

Thank you so much for your input, Mr_Pot. I think you are absolutely right. I had similar thoughts but this evident statement and clear definition of "non-diabetic healthy individuals" that have 4.0 to 5.9 mmol/L completely confused me.
 

Right, but you could also do it normally, take readings before your meals and two hours after your meals. If you eat for example 4 times per day then you will have 8 measurements per day. This will result in your glucometer to collect all the data needed to show you correct monthly averages. If you take your readings once a week at random times and just out of the blue then of course your meter will never have any accurate monthly figures.

I agree that the HbA1c tests are more accurate, but you do not do them every day at home, therefore I am trying to make the most of my glucometer and to use it / understand its readings to the best of my ability. I also think that an idea of approximate values and figures is not quite right here.
 
Klpville said:
I agree that the HbA1c tests are more accurate,
Click to expand...

Not always. There is still a margin of error allowed, and for those people with red blood cell variances or certain other conditions the HbA1c can be wildly inaccurate. I trust my meter far more than my HbA1c.
 
I was also wondering does anybody also have your blood pressure skyrocket when your BG readings are high? You may not necessarily feel your glucose levels, but your blood pressure will surely signal it to you without any meters and all.
 
In my opinion, blood glucose and even HbA1c are both overrated metrics in people with a metabolic question mark over their heads. Whilst of course they both provide crucial data, they ignore the most important piece of the puzzle - insulin. I believe that the over-reliance on blood glucose concentrations is misplaced, and health teams should be measuring insulin in the first instance.
 
Klpville said:
This will result in your glucometer to collect all the data needed to show you correct monthly averages.
Click to expand...
Sorry but it won't.. as it won't show what happened overnight. Your blood sugars are in a constant state of flux, they change from one minute to the next dependent on all sorts of factors so I'm afraid unless you finger prick say every 5 minutes for a full 24 hour period (i.e. what the freestyle libre does) then you still won't have any reliable data.
 
I’d just add that fasting and pre meal are not the same thing as you seem to think. Fasting is an extended period without food such as overnight or longer. Preprandial might only be a few hours after the last intake and potentially not back down to a baseline following that food. So the two ranges aren’t as interchangeable as you are trying to make them.
 
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This is true, and also a real fasting test should be taken after sleeping so that it includes the early morning glucose release. How the body handles this morning rise is a very telling measure of insulin resistance.
 
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