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My GP thinks a fasting blood of 7 or above is normal???

S

Sula Maye

Member
Messages
5
Type of diabetes
Prefer not to say
Treatment type
Diet only
Hi

I have been wearing a libre thingy me bob CGM. It showed f that frequently my fasting blood glucose was above 7, even after fasting for over 16 hours on one occassion, but my HBAlc comes in as normal.

I flagged this up with the diabetes GP in my practice and finally got to speak to her this morning. She told me that the guidelines are for fasting glucose of 11 or below to be normal when i pointed out mine were rarely not 7 or around that, and that she had worn a cgm and got similar results and therefore she could not diagnose or treat me as type 2 diabetic.

I have asked her to refer me to endo for a second opinion but is she right??? I am in
Wales but surely that doesn’t change the facts?

I will try to attach a screen shot of a graph. Up until the large spike I did not eat from 7pm the night before

I eat a very plant dense, non ultra processed, wholefood diet, but do eat home made sourdough once a day and chocolate a few times a week. Even when I was keto I couldn’t get below 12 stone and without being keto my body just climbs back to 14 stone. I am just puzzled by my GP’s response. Any info or advice?
 

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Hi and welcome. We can't diagnose here, and we shouldn't even try, but I hope this is helpful -

T2 Diabetes can be diagnosed in a number of ways:

-HBA1c equal to or greater than 48mmol/mol (or 6.5%)
-A random plasma glucose level equal to or greater than 11.1 mmol/litre in someone with typical symptoms of diabetes
-A fasting plasma glucose level equal to or greater than 7.0 mmol/litre
-A plasma glucose level equal to or greater than 11.1 mmol/litre 2 hrs after a 75g load of glucose given by mouth (the Oral Glucose Tolereance Test - OGTT)

(taken from Bilous and Donnelly's Handbook of Diabetes)

Most people these days seem to be diagnosed via HbA1c. Do you know what your last HbA1c was?

There's nothing particularly unusual about a reading of 7.0mmol/l. It's within normal range albeit towards the higher end. If you have an enthusiatic liver it may be topping up your blood glucose levels from its own stores, because it has got used to you running with higher levels. This is very often seen first thing in the morning - the "dawn phenomenon" effect. 16 hours without eating probably isn't enough to totally deplete your liver's glucose stores.

I'm not seeing a spike on your graph. There's a small rise from 7ish to just over 9 (lunch?) and (importantly) a fairly quick fall, and a further similar rise and quick fall around 6. If you ate around those times then that's what you would expect to see - a rise as the carb in the food is digested to glucose and passes into the bloodstream, and a fall as your insulin deals with it.

Rise and fall in blood glucose in response to food etc. is perfectly normal, as you will have seen from your CGM.
 
Thanks for replying. My last hbAlc was 38. It isn’t the spike after eating me that concerns me, I expect that, it is that my levels are around 7 all night despite me having eaten last at 7pm the night before and me not eating again (on that occasion) until 1pm, hence the spike that followed.

Why does the guideline say a fasting blood of 7 if that is in fact normal? I thought they counted fasting as 12 to 14 hours for that? How does the liver play into this, i would be interested to understand more. As I have M.E and also a NAFL which started with my M.E 12 years ago and I have also been hypothyroid since 1994, so have lots of other systems which don’t function very well.

I also intermittently fast, couldn’t that fact distort my hbAlc compared to someone eating in a window of more than 8 hours a day?
 
Bear in mind that Libre is not that accurate for some people. You are seeing 7.0 but with an accuracy tolerance of 15%, this could be less than 6.0.
The Libre is great for seeing variations but without a finger prick to judge the accuracy of a sensor, it could be further out for you.
 
Thanks, next time I put one on I will finger prick too to see the variability. I suspect doctors will say they aren’t reliable either. When I was first I’ll I used finger pricks sometimes my blood glucose was as low as 1.6 (I was very I’ll at the time) GP’s just dismissed it. I don’t want to be diagnosed type 2, however i equally don’t want something harming my body undiagnosed. I don’t understand why my GP thinks 11 is the criteria when NICE says 7 fasting. It doesn’t make sense to me.
 
I understand from the Handbook that screening for diabetes via fasting plasma glucose does not capture exactly the same population as those diagnosed by HbA1c or OGTT (I don't know (personally) of anyone who was diagnosed via a FPG test).
There are some things that affect HbA1c results (eg anaemia or renal failure). It's viewed as a better test because of low biological variability and because it effectively tests over several weeks. It has diadavantages (according to the handbook) and one is that "some patients and ethnic groups may be diagnosed with diabtetes by some criteria but not others".

Given how many of us do some form of intermittent fasting, and that the point is to lower blood glucose and therefore HbA1c, I wouldn't call that distorting the Hba1c result. It is a count of glycated red blood cells and the IF etc is intended to lower it. Your A1c is roughly where mine has been but my fingerprick readings are mid 4s to low 5s, which is what you might expect.

As well as the Libre accuracy issue, I wonder if you tried a few days without carbs at all to see whether it made any impact? If your numbers fall, then you have a better idea about what's giving you the daily readings.
 
Thank you. Do you mean no carbs as in no veg, only fats and meats? What would you expect to see happen, in terms of what response would indicate what? Is type 2 diabetes purely about the glucose in your blood in response to what you have eaten, or is it also about the glucose in your blood because your liver is putting it there? I thought it was the glucose in the blood that does the damage whatever the source of that glucose?

My body seems very bad at getting glucose into my cells (as indicated by the lack of energy I have access to) , but really good at turning it into fat and storing it in my body and liver, (as indicated by my weight and NAFL) does insulin resistance mean all cells are resistant to having glucose placed in them, including fat cells, or just the muscle cells which need energy?

I would be happy to eat only veg and fats and proteins for a few days to see what happens, but I’d like to know what different reactions would be signifying?

I was keto for nearly 3 years, trying to treat my M.E but it was a very miserable existence cut off from the communality of sharing food with my family, and when your life is limited to a bed and a house and even socialising with your own child is limited food is one of the only pleasures in life, so even harder to eat keto.
 
I don't know how many carbs you're eating at the minute so tried not to be prescriptive. This has worked for me in the past. If you reduce carb intake significantly, whatever that means in your case, you might possibly see some reduction in the current readings - less carb in, less glucose. As I understand it insulin resistance refers to the resistance of the muscle cells only, not fat cells.

if that doesn't happen it might be that your liver is very efficiently keeping your glucose levels high, and it will take a while longer for glucose stores to be depleted. You might see some reduction only then. Can you remember what sorts of results you were getting while doing keto?

The glucose issue is that high levels of glucose cause physical damage. Our bodies need around 130g glucose a day, but if that doesn't come from carb it can be manufactured in the body from bodyfat or protein. If you are maintaining a level of over 7 mmol/l most of the time you're looking first to see what (if anything) might affect it.

The other thing to remember is that not everything is about diabetes. It is possible that there is something else in play here - you are doing the right thing by trying to get a referral.
 
Thank you. Yes, my GP has agreed to refer me to endo, hoping they are a bit more informed than she is, but I wouldn’t count on it. My thyroid endo wasn’t that on it.

I see, you meant try to get my bloods down with diet. I have worked with a functional nutritionist in the past and done loads of research on the gut microbiome etc in my attempts to recover from ME and my diet is such that there aren’t anymore changes I could make and sustain for the rest of my life. I think this was one of my concerns, how bad would my blood glucose be if I ate like someone who had not already addressed their diet so comprehensively and therefore it’s not like I can tweak my diet. I also know how to manipulate blood glucose with cider vinegar and combining healthy fats with carbs to slow the release of glucose. The only thing I could remove would be the organic chocolate I have on a Saturday or Sunday night, but funnily enough chocolate didn’t spike my bloods much at all
 
Hi, I have similar random spikes sometimes 7 upon awakening. My research led me to realise the liver provides a natural “spike” into the bloodstream every morning upon waking up. The liver releases a dose of glycogen, this allows the whole system to get an energy boost and get your muscles ready to work…..it seems to be a natural and regular occurrence, sometimes above 7 and sometimes closer to 5.5…. It does depend how much glycogen the liver has stored in it, and previous consumption in the days leading to the fake “spike” do seem to affect the result. But I’ve been told the important overall test is the Hba1c, it’s more reliable. The daily morning finger prick is an indication of the swings but not of the bigger picture. I treat it as a warning sign now. I too tried low carb for 20 years nearly. It became intolerable as my CCL gross carb limit was only 20grams. Yes it alienates you from society and the act of sharing simple things with your loved ones. Plus post menopausaly it sent my bloods and heart haywire. I’ve switched to low fat and have managed to stick to it solidly for 6+ months and at last shedding the excess fat but also feel more heart healthy and able to feel more part of the social side of eating. But I still try and adopt the low carb lessons I’ve learnt and make sensible choices. Obviously very little sugar, 70% Lindt as a treat. I allow apples and bananas but use a lot of soya based yoghurt and milk and cream now. Dairy to a minimum though and no red meat. i thought I’d mention about the morning spike theory though and even after my soya yog and small portion of Greek mix, my blood sugar quickly returns to mid 5s, for me the morning spike is acceptable as I now understand the physical process my body needs to “start my engine” and get the power I need to move. I hope that all makes sense x
 
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