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High Fasting Bg Level Even After Fasting

I had a dissapointingly high bg reading today even though I'm on the LCHF diet and had also fasted for 16 hours. It was 5.8. I would have been expecting 5 or below. I'd also just walked several miles with my dog. Can anyone explain why this is? Has this happened to others with fasting rates? I'm a tofi so I don't know if that makes any difference at all.
The accuracy of most brands of meters and strips is around +/- 15%. You may well have been within target.
Obviously this won't work for you because you're fasting but I found that having a small snack before bed stopped the morning higher readings.
 
I have had a few pleasingly lower rates but though they would be really low after the longer fast and the exercise.

Is it possible that this is gluconeogenesis coming into play? Often diabetics can't fast for that very reason. Fasting is fine for some, not for others. Exercise will also raise BG in some diabetics.
 
I have been doing intermittent fasting since last Monday, also on the LCHF diet. I have seen a lot of low (for me) results, but I "accidentally" ended up doing a 63 hour fast this week because I am eating when my meter comes into target range, and my readings just didn't come into the range. I eventually broke the fast yesterday morning, as I am eating out tonight, and I didn't want that to be my first meal.

I was surprised to see higher results during this extended fast than some I had the week before eating one meal a day, but I think I may have had a cold this week, as I had a very slight sniffle for a couple of days, and I have read on these forums that colds can make your blood sugars go up.

I am back to a low level of fasting blood glucose this morning and no more sniffles - I will have to see what the next few days readings are like, but at the moment I am swinging towards the cold as a possible reason.


Please google gluconeogenesis. This is probably why you are getting high BS even after fasting. Some diabetics just aren't cut out for fasting.
 
I must be really thick, but I still don't understand how the liver is continuing to make glucose when you keep your carbohydrates down to a minimum. I've read that your body converts from glucose to ketones, and ketone bodies are a completely satisfactory and efficient fuel choice for your body, and are an alternative to glucose (ie when you become fat adapted). So once you've exhausted your glucose supplies, and you're running on ketones, does the liver continue to make glucose, and if so, what is it made from (especially if you're limiting protein, because from what I understand fat can't be converted into glucose)? I've tried to find something scientific about this on google scholar, but everything so far seems to be about fatty liver disease and doesn't seem to cover what the liver is converting to glucose.

Just google gluconeogenesis, it's a recognised phenomenon, and there will be lots of scientific papers regarding it.
 
If you're on metformin, you need to be careful of hypos


Not so much with metformin, since it's function does not directly lower blood glucose. Metformin works by helping to improve insulin resistance. It can also help with high morning fasting glucose. The other diabetes drugs are far more likely to cause a hypo than metformin.
 
Please google gluconeogenesis. This is probably why you are getting high BS even after fasting. Some diabetics just aren't cut out for fasting.

The results were not "high" they were just a little higher than the results I had seen the week before, which were in the normal range - I will google your suggestion, though, and find out more about that. The week before when I started intermittent fasting with fasts of between 18 and 29 hours, my BG got lower every day and I was producing ketones according to my rather crude testing method (a cheap breathalyser detecting breath acetone) and a friend's nose, who could smell it on my breath.
 
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The results were not "high" they were just a little higher than the results I had seen the week before, which were in the normal range - I will google your suggestion, though, and find out more about that. The week before when I started intermittent fasting with fasts of between 18 and 29 hours, my BG got lower every day and I was producing ketones according to my rather crude testing method (a cheap breathalyser detecting breath acetone) and a friend's nose, who could smell it on my breath.

Good luck! Sometimes it takes a while for BS to come down to what we expect.
 
I think 'The Diabetes Code' by Jason Fung explains it quite well.
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Take care all.
 
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