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The power of fasting blood glucose

finsit

Well-Known Member
Messages
331
Location
UK
Type of diabetes
Type 2
Treatment type
Diet only
As i have mentioned in one of my other posts, i am kinda obsessed with daily finger pricking and check somewhere between 3-6 per day since last few months, even though my blood glucose levels and my a1c is in non-diabetic range after starting low-carb as advised by Dr. Richard Bernstein.

So, i was doing some trial last few weeks to see which BG level could possibly give me the picture of 24 hours. I found through lots of experiments that if i had more carbs, free meal or cheat meal in a day, my fasting blood glucose remains a bit elevated for the next three days.

Example: I had some serious bread one day and my BG went up to 9 mmol/l. Even though they came back to mid 6s after 4 hours (which i was happy about), my next day fasting BG was 6.1. I continued my routine low carb and the fasting BG the day after was 5.7, then 5.3 and on 4th day it went below 5 (which is my normal).

I have just given one example, but i did try this with some sweats and other high carb diets and seen the similar FBG results for 3 days.

What are your experiences in this regard? For me, i can clearly tell how my yesterday was based on my today's fasting BG. So, if I have to rely upon just one testing, probably i can do that on my FBGs.

In case you are wondering, i have my last meal before 7 pm and i test my FBG around 7-8 am next morning.
 
I ignore my fasting blood glucose levels. After nearly 10 years, it is still around 7-8 every day. I dont even test it anymore, except maybe a few times a month.

what is important for me is my pre and post meal readings, as they highlight spikes and things I may need to tweak or take notice of.
 
Thank you for your input. Can we then assume the higher a1c you have, the more FBG becomes irrelevant?
 
I've found the same. The bloke shape wanted take away pizza a week or so ago, I had some mozzarella sticks (it was the 'best' option on the menu. I was not tempted by the pizzas from there because he and I do not share the same taste in such things)

My BG was raised above normal-for- me for about 36 hours.

Similar result when I had some strawberries. I had quite a lot - I am a huge fan of fresh fruit, especially berries. The numbers weren't as bad as with the actual junk food, but it still took a day or so for my numbers to get back to my normal.

I am 'only' pre-diabetic, but I've been monitoring closely since I was told about it.
 
finsit said:
Thank you for your input. Can we then assume the higher a1c you have, the more FBG becomes irrelevant?
Click to expand...
I have no idea if it has anything to do with HbA1c level. Why do you make that assumption? FBG only measure the size of the glucose dump just prior to waking.
 
finsit said:
my a1c is in non-diabetic range after starting low-carb as advised by Dr. Richard Bernstein.
Click to expand...
What with following Dr B's protocol (most of the time!) and having such an enquiring and meticulous mind, you are all set for success. Well done!
 
Alexandra100 said:
What with following Dr B's protocol (most of the time!) and having such an enquiring and meticulous mind, you are all set for success. Well done!
Click to expand...

haha you are right, but i thought sharing this may help others in the community and i may get some reassurance from other's experiences, not that i am highly concerned
 
The one thing a low FBG can do is really knock down your A1c, if you run in the mid 4s then in theory you could spend 18 hours a day with an average BG of 4.5. Only rising after low carb meals before falling back at the 2 hour mark. Indeed it could mask unknown high spikes at mealtimes if you didn't check & just relied on yearly A1cs. I do think all these metrics will be replaced by TIR in the near future.
 
I never watched my FBG, i was more after post-meal spikes all these months. Its just now that i know my food and spikes, i am trying to correlate my yesterday food affect on my today's FBG and it seems to correlate well so far.
 
As someone who does test his fasting blood levels, this is because I'm non diabetic and it would be a warning that something isn't quite right.

The experience of having carbs and still have symptoms a couple of days later.

In my case it does feel if you are drunk or a hangover the next morning when I have a hypo. Typical RH symptoms appear and you have brain fog.
There is also the rebound effect if you treat the hypo with too much glucose. This will go on if not addressed.
My last eOGTT, when I crashed very low, left me with symptoms similar to a bad viral infection. It floored me for a few days

There have been some on here that suffer from hangover symptoms.

In T2s, it's more important to be as close to normal levels as much as possible. And low carb diet is recommended. So it's the meals you are measuring, before and two hours after.
Hba1c is the guidelines, to deliver a diagnosis of T2 or prediabetic levels.
My last Hba1c was 37.
 
Hi @finsit , wow you have such an enquiring mind! Your posts are always very thought provoking.
Without wanting to enable your obsession, have you tried wearing a Freestyle Libre for a couple of weeks? I have only ever tried one and found it very enlightening. The first week I ate my regular foods at my usual mealtimes, then the second week I tried some little ‘cheats’ like six chips with a meal. They are expensive but I thought the cost was well worth it for what I learnt from it.
 
Hi @Rachox thank you for your kind words. I wish i was this inquisitive about my health 10 years earlier

I thought about CGM but i know myself, i will enter into another obsession that will cost me dearly So, i am just relying on glucometer and trying to reduce it down to FBG using my experiments.

One other thing, which we all know here, is the carb sensitivity once you are on low-carb diet. I have experimented and a similar high carb food will spike me higher the first time and the spikes will start going down if i continue day after day the same amount. That is why they say you need to start eating high carbs few days before the run up to your OGT testing. However, I feel its too unhealthy to get used to high carb just to test your carb-threshold and secondly, if i am not spiking much higher on high carb, i still will be having high insulin levels that i can't check with each meal. So, I will do the CGM experiment once i get rid of finger prick obsession, im done with all my experiments and i have stable BGs for at least 6 months. Currently, my post meal still reaches 7 mmol/l and stays in mid 6s for few hours, so i don't return back to below 5 in 2 hours like non-diabetics do. So what worked for me is the early last meal and delaying breakfast so i have few good hours on low BG to compensate my average. Does anyone think several hours in 6.5-7 mmol/l range a day will still get you to diabetic complications? Secondly, is there any study of complications in people who had borderline a1c (lets say early 40s) but were very physically active ?
 
I agree with @Rachox A Freestyle Libre would benefit you I'm sure. I wore them for a year or two, but that was 2 or more years ago now. I learnt so much about what was happening between finger tests. Even overnight when I was asleep it was interesting to see what was happening. I noticed in particular I had a rise corresponding with a visit to the loo, and even when resisting the visit to the loo with a full bladder for a time. I have never had a problem with my FBG. Even just after diagnosis over 7 years ago it was always low 5's and has remained so. I can sometimes go to bed between 6 and 6.5 if I have eaten rather later than usual, or had a carby snack but return to the same low 5's by the time I get up. I was out for a celebration family meal last night and could not resist a dessert - probably the worst dessert of all, an Eaton Mess with strawberry ice cream, cream, strawberries and meringue. Yet this morning I was back in the low 5's. I think it all depends on our own bodies and how our livers respond. Mine seems to behave itself.
 
finsit said:
I wish i was this inquisitive about my health 10 years earlier
Click to expand...

@finsit , yes I expect most of us would turn the clock back if we could. We all have to find our own personal way in dealing with our diabetes. Best of luck and I’ll continue to read your posts with interest.
 
I do not have a clue whether this is a coincidence or not, but since having two bags of blood transfused a month or so ago, my fbl have slowly come down.
 

I have read of pre-diabetics developing mild retinopathy/neuropathy.
What you don't know if these pre-diabetics ran high or spiked high.



Personally I'd rather be the 3rd graph, running high but smooth.

Here is the often quoted microvascular complications chart, you can see that risk steadily increases once you step into the pre-diabetic zone.



Non-diabetics can get complications too but as you can see their risk is far lower.
 
Another for periodically using a CGM. I buy one every quarter or so, or when I have a new plan to test out. It was mentioned that dawn phenomenon might happen before you wake, but not for me, it’s foot on the floor.

I’m about to get another as I have a new plan I need to test lol
 
Bear in mind that the chart shows "relative risk". If non-diabetics didn't have complications the relative risk to diabetics would be far higher.
 


The only thing I’ve taken from this whole thread is you got to eat an Eaton mess….I’m so jealous lol
 
Yep, I’m totally the same, with albeit limited experience, based on caving once for a bag of m and ms - expected rise then drop slowly but pay for it the day after with slightly elevated levels (but luckily not too bad). Would love to know the science behind it? Some kind of liver top up that is released the next day?
 
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