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BG not falling during 48Hr fast

J

J_P

Well-Known Member
Messages
52
Type of diabetes
Treatment type
Diet only
Morning - quick question for those with more experience than me.

I try to do 48 hour fast once a month - currently about 37 hours in to Octobers

Before the fast my BG (finger prick) was 6 (sunday 8pm)

Yesterday it fell slowly throughout the day as the fast progressed bottoming out at 5.2 yesterday at 8 pm (24 hours in)

This morning's fasting glucose was 6.5 (not to worried as its the inevitable liver dump) - however it doesnt appear to have fallen - sitting now 2 hours later at 6.4.....

Any thoughts or potential explanations ?
 
What are your expectations?
Firstly the error allowance on B meters is +- 15% so you can only rely on approximate values and trends.
Secondly you can't control your liver dumps exercise, or just moving around, lack of sleep, stress, infection, illness, medication, in all around 40 different things can affect them.

I only do fasts over 24hr when I need to for a colonoscopy, normally I eat 1 or 2 meals per day (Time Restricted Eating). But when I do the nurses always seem to panic when I say I'm a Type 2 diabetic and say I have fasted for over 48hrs. They are OK once they see my BG reading which are always in the high 5's.

I'm aware that some people in the forum post much lower FBG figures, but we are all different, so perhaps 5.2 is about as low as your liver will allow you to go - there is nothing wrong with that!
 
i suppose i was expecting a gradual decline to around the 5 mark - was just curious to why today it has stayed up post the usual liver dump

Thanks for the perspective on accuracy of the B meter
 
JustinP said:
i suppose i was expecting a gradual decline to around the 5 mark - was just curious to why today it has stayed up post the usual liver dump

Thanks for the perspective on accuracy of the B meter
Click to expand...
I have limited experience of longer fasts, I tried them and they're not for me, even with the reduced appetite from keto. However, 16:8 works very well for me with 2MAD.

For the 4 or 5 attempts I had with longer fasting of 24 hours, my average BG across all readings that day was higher than on days where I eat 2 or 3 low carb meals. I put this down to my liver likely panicking and dumping glucose, because it interpreted an empty stomach as "imminent death from starvation could happen". When I eat low carb meals, I'd hypothesise that my liver doesn't do this, so it seems to play less of a role in factors affecting BG readings during the day.
 
Paul - i reckon you are on the money - liver feels i am going to starve (not much chance) and is dumping as much glucose as possible - however i do think that in the absence of food this glucose has got to come from visceral fat stores - maybe a higher BG reading is therefore not a bad thing
 

I do 16 hr fast everyday. 1st meal at 12 low carb and last meal at 7:00m low carb. Exercise 20 minute
 
Just a question on this, if the liver dump is happening is it better to let it do that and go with it until such time as there is less glucose to put in the bloodstream? I'm low carbing doing a 16:8 fast so really just two meals per day (as of Saturday I've started doing this properly so not even a week yet ). My blood glucose rises in the morning and then levels out a bit, gradually going lower especially after I've been out for a walk in the evening. (I'm using a CGM) I know about the dawn phenomenon but I saw a video on youtube where the lady was saying keep going with it, it can be days for some people, weeks or months.
 
There's not really a great deal you can do directly about what your liver gets up to. I've found that three almonds will reassure it that I have some food and it will stop topping me up in the morning. Otherwise it will go on increasing until at least 3pm (which is where I got bored and stopped testing).

My fasting morning level is still the highest I'll usually see all day - mid to top end 5s. This is after nearly five years on 20g/day. It drops steadily through the day into the evening depending on what I do, and what's going on. It's usually 4 something before the evening meal, and will go up a bit after eating maybe to mid 5s, depending on what I've eaten.

You hold round about an estimated days' worth of energy in muscle and liver stores. These obviously can get run down, and will be topped up when spare glucose is available. Those of us who aim to be in ketosis most of the time are using mainly ketones from metabolised bodyfat for energy.
 
My usual dietary regime is intermittent fasting.
And I only eat between mid afternoon and 7pm(ish)
But I do occasionally do longer fasting.
Mainly to return to ketosis or because I can.
I learned so much from my first, which was eighty (ish) hours long.
I like the energy levels, no hunger and I feel regenerated.

My first was a test to see if I go hypoglycaemic if I don't eat.
I didn't.
I was relieved because going hypo whilst fasting could be a pancreatic condition.
Or other conditions.

I lost a lot of weight after my first fasting, doing very low carb and keto.
It also helped my health.

Some can't fast for many reasons, but it is a tool used in a treatment of metabolic conditions.
 
J_P said:
i suppose i was expecting a gradual decline to around the 5 mark - was just curious to why today it has stayed up post the usual liver dump

Thanks for the perspective on accuracy of the B meter
Click to expand...
If you are able, try to watch some YouTube videos by Prof Ben Bikman he is an expert on insulin and the effects on the body and what causes insulin resistance and how to combat it, he is amazing.
 
Reactions: J_P
I do 8/16 fasting daily. I have more or less gone further to just a 2 meal regime with protein snacks inbetween. I also fast every 3 months for 72 hours+. If you your average BGL is over 6, manage expectations, in so far as, your system will need to get used to fasting if you do not fast regularly or interval fast regularly. My first time it took 2 full days before my liver had eaten through its glycogen reserves. It has to be a water fast. If you cheat by more than 2 carbs, it throws the Ketosis back out of sync. Then boom, I was at 4.5. In Ketosis and feeling great. Now you have 2 options. Keep the fast up and push out into autophagy for another 25 to 28 or even 72 hours, or leave it there and break the fast. I do not measure BGL now until my 72 hour point. I have done a full 100 hours. To fool the system, use Tbls psyllium husk to make a drink with a herbal tea or water. I use Liquorice root I grind down to make a tea. I also drink a bullet proof coffee with MCT oil pnce im in Ketosis. That also fools hunger pangs. If you have a good Diabetologie, do a fast in his oversight. Do a BGL with them at the start and finish. Then you will get the gyst for future fasting. I do weights and am very active. I eat more carbs than most. But I keep the sugars in them low. Top tip.....Dry roasted Edemame is a fantastic snack for us. Brilliant for those with an active lifestyle.
 
Be careful as don't forget when body has no food to work on the liver releases sugar as body thinks it's starving . It's a natural occurrence to save your life in emergencies. Depends also on you and how long your body takes to use stored insulin.
Just be patient & get expert advise on liver sugar releases.
Personally not fan except religious exceptions. Believe in little and often is best. X
 
Please bear in mind that if you drive, legally your Blood Sugar must be a minimum of 5mmol/L so safest to keep at top end of 5s or higher. If you have an accident or roadside check and it is below 5mmol/L you will be prosecuted.
 
Standard4 said:
Please bear in mind that if you drive, legally your Blood Sugar must be a minimum of 5mmol/L so safest to keep at top end of 5s or higher. If you have an accident or roadside check and it is below 5mmol/L you will be prosecuted.
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This only applies if you are on hypo inducing meds like insulin or Gliclizide, which obviously make the chances of having a hypo much greater the OP and most of the posters in this thread are T2 diet only, lots of none diabetics drive under 5 and it’s not illegal to do so
 
I regularly do 36 - 48 hour fasts and this happens. Usually the higher value is the first reading of the day. I have always taken the view that it means I am in fat burning mode - yeah!
 
Just noticed this response, and popped in to stress, that the purpose of fasting is to affect your hormone balance without your body thinking that you are starving - it's entirely the point of the word "intermittent" in "intermittent fasting" - not eating is not the same as starving, and gradually reducing your calories in the kind of calorie restricted diet that most people are advised to do - that it what your body interprets as starving, and dials down your baseline metabolic rate to compensate.

Not everyone will respond in exactly the same way; and depending on your eating and snacking habits, you may feel like you are starving every couple of hours; I think you have to ease yourself into fasting or be prepared for exactly the kind of cold turkey reaction that you will get to stopping any substance that your body craves - but you should understand this as a craving; you are not starving.
 
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