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Maximum Blood Sugar for someone without diabetes?

Hi i am just wondering what is the absolute maximum blood sugar someone without diabetes should have? I mean highest point at any point in the day?

Hi,

I think it is important to distinguish between an occasional, short duration high peak, and the habitual lasting highs that a diabetic can experience. Also important to distinguish between the peaks that type 2 diabetics on meds or not on meds get, and the peaks that type 1 diabetics get.

As I understand it, if you rocked up to a random blood test at your doctor's surgery, and the results were over 11, they would test for diabetes (by doing an HbA1c test).
If you were under 11 they might also do an HbA1c, to see what was going on, because that 11+ is unlikely to be a one-off.

But in basic terms (because it is really quite complicated) a non-D may get quite high peaks that look out of 'normal' range, but if the blood glucose level comes down quickly, then that is much more 'normal' than for a diabetic where the same high reading may take hours to come down, or may just stay high.

However, I would take the view that true 'normal' isn't anywhere near 11mol/l at any time, and would be interested in finding out what foods were sending my blood glucose above 7mmol/l, and in what portion sizes, and I would be scrutinising the www.bloodsugar101.com website to see the information there, which shows a number of different perspectives, on what 'normal' looks like - and what the consequences of 'above normal' blood glucose could be over time.

Either way, the NHS and I have very different opinions on what healthy blood glucose levels are...
 
I have only experienced in excess of 11 on a few occasions 12 and 12.5
 
What is normal is an arbitrary definition based on standards that have been revised over time and will likely be revised again in the future.

In this CGM study, 16 of 38 people who are “normal” based on standardized fasting BG and OGTT criteria had blood sugar spikes into pre-diabetic (>140 mg/dL) and some even to diabetic levels (>200 mg/dL). One recommendation of the study’s author is that it might be best for everyone to avoid foods like corn flakes and milk.

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005143

In this study of normal glycemic people, some people reached peaks of about 150 after a high carb breakfast, but blood sugar stayed under 140 mg/dL for more than 99% if the day, so the peaks must have been quite short.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2769652/

As more studies are done with more accurate CGMs like the Dexcom G6, the should be better info that emerges as to what is truly normal.

Personally I believe a person with truly healthy glycemic control would rarely see blood sugar over 120 at peak even after a very high carb meal and would normally see blood sugar back well below 100 at 2 hours.

Truly healthy would be at levels not causing any arterial damage.
 
You have made a range of remarks in this, so I've felt the need to break them down and respond.


Yes, everyone is different. But you only feel that way because your body has adjusted to your levels being relatively high, that doesn’t mean that is normal. You may get false hypo symptoms from this as well as being ‘ok’ with highs.


I haven’t studied medicine, but by what you are saying for somebody to have knowledge of something medical related they must study medicine? People on this forum have much more knowledge than GP’s, but their knowledge doesn’t mean anything because they haven’t studied medicine? Medicine itself is much more than teaching about diabetes, living with the disease and having an obsession to make your life better, can’t be taught, I read a lot about diabetes as a passion. From what you are saying you seem to have studied it, but don’t seem to know the basics. I don’t believe that is the general consensus, and if you have read literature or papers showing evidence, please provide some links to enlighten me.

I also learn a lot form Dr Bernstein, who is one of the most renowned in diabetes management, and obtaining normalised glucose levels. Not mediocre standards, true non-diabetic levels. Dr Bernstein was met with comments exactly like this, having normalized his glucose levels to non-diabetic levels and reversing complications 'experts' thought were not possible, his experience and knowledge had no value as he didn't have the piece of paper to say he studied medicine. So at 45 years old he studied medicine ad started working in the field, did he change what he had been doing beforehand? No, he built upon it, so his knowledge was still there. He had a lot of pushback because his methods would cause financial loss to major firms.


Post meal and after eating are exactly the same thing. Before eating would be pre-meal. Just as in post prandial glucose levels are levels after eating. Dr Bernstein has mentioned many times, when he sees patients with 200 md/dL at any point, even a couple of times per month he would treat them as early diabetics. 10-11 mmol/L after meals is not normal levels.


They may want to get tested for early or pre-diabetes, if that’s the case often.


Its good control, still not non-diabetic levels and I don’t achieve this by advocating mediocre control or believing 10-11 after meals is ‘normal’. To be able to better my diabetes management I have to know what the true non-diabetic levels are. There has been many studies which show the normal hba1c is around 83 mg/dL (~4.6mmol/L) and this is in adults with children slightly lower, and this is definitely not achieved by having ‘normal’ peaks after meals of 10-11. The J curve which has been shown by a number of studies (which I’m sure you are aware of, being a medical student) shows that the mortality rate increases both above and below the normal level of 83 mg/dL. If you are happy with your control or wish to manage your diabetes knowing the risks, then that’s your choice. But you can’t push stuff as being normal, when it is not. People need to understand what normal or true- nondiabetic numbers are to be able to strive towards it.


As above, please provide links to some of this literature. I don’t take what GP’s say as gospel, as the err on the side of caution. The reason the hba1c target is less than 7% is to ensure they don’t get sued for deaths by hypoglycaemia, not because they know that as ood control. Doctors have been pushing many things over the years as normal, which clearly have not been the case (prime example of high carb). Again 11 is not ‘normal’ levels for non-diabetics. I’m sure you have heard of Dr Bernstein being a medical student, but I suggest you read his book.

Sorry for the long post, but people can't achieve good/non-diabetic control if they want, without knowing what the true base conditions are. Dr Bernstein is a perfect advocate of this and his book is a must read, regardless of low carb or not.
 
@Sapien - this is a very helpful contribution - your comments about my situation would be appreciated. From my own testing over a few years mean averaging - I have noticed that being 'naughty' the previous day from after lunch which is my main meal - will be proven by my pre-lunch testing the following day. BUT I have been able to show consistent readings within 6-7 mml
(108-126 mg/dl) and only once have I achieved 5.6 mml (100 mg/dl) in all that time. But those readings are at that time and I take up to 4 hours to come down after meals most of the time. My concerns have always been because of the One Touch Ultra advertisement on their meter showing '5.4' as being normal. I have only achieved this success (I think) during the past three years going to low-carb. Diabetes has done its worst for me giving me Congestive Heart Failure long before diagnosis and subsequently extreme Diabetic Neuropathy. We have no experts in S/E Asia so this is why I am asking you for your opinion - readings between 6-7 mml appear to be normal for me - what do you say? Thanking you in advance.
 
I actually had a meter and tested off and on before I was a diabetic or even close to being a diabetic. My fasting level first thing in the morning was always 5.6-5.7 (100-102). My after meal level would go up to around 7.5 (135), but drop back down to 5.6 (100) within 2 hours. I don't have a clue what my A1C was as they didn't test it until years and years later when I started having issues. I caught my blood sugar when it first started fluctuating and I woke up to a couple of 6's (108's) and panicked and went into the doctor immediately. Of course they ignored my concern as I wasn't that high yet. But I knew I had had an uncle that had type 1 and I was concerned and it turned out I was right.

I do stay under 7.8 (140) 96-99% of the time.
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