• Guest - w'd love to know what you think about the forum! Take the 2025 Survey »

Fasting and Rising BG

I have had a bit more of a serious attempt at this over the last three weeks - trying to get a bigger sample size - been fasting min 20 hours, three days per week (Mon, Wed, Thu) - so from 8.00PM on Sunday night to 6.00PM
Had you thought about extending the fast so you did say 3 days .. I found that extended fasting led to lower numbers,, usually down in the high 3's on the third day. I just went back and checked my figures and haven't really seen BG's rise when doing shorter fasts at least not consistently but then again I haven't been a very consistent OMAD faster I usually just do 16:8 or longer fasts.
 
Had you thought about extending the fast so you did say 3 days .. I found that extended fasting led to lower numbers,, usually down in the high 3's on the third day. I just went back and checked my figures and haven't really seen BG's rise when doing shorter fasts at least not consistently but then again I haven't been a very consistent OMAD faster I usually just do 16:8 or longer fasts.
Thanks - I was thinking of extending the fast for longer period to see if that brings about the desired effect - may try it next - I have been surprised by how easy it is to fast - especially just continuing from overnight until evening meal - just really disappointed with the results so far.
 
Hi @Element137 - interested to read your latest experiment, because I found exactly the same response. I did daily fasts recently for 10 days straight, 1st-10th October, eating only evening meal, though I continued with tea/coffee/water as normal. My BS levels were raised at every test, sometimes by as much as 2mmol/L. Previously my rise had been around 0.5-0.8mmol/L. This was totally the opposite of what I was trying to achieve, and I stopped the fasts, and returned to my two meals a day from 11th October onwards. What I find even worse - is that my numbers have remained higher, still in the 6s, whereas previously I had always been in the low-medium 5s. My meals were no different from those I usually eat - it's very disconcerting when you haven't a clue why things have gone awry.
Agreed - I am trying to shift last 10-12 pounds of weight and was hoping that IF would get me going again - but I don't really want the increased levels that are evident at the moment.
 
I suspect (and I only suspect) that it is insulin resistance causing your problems. You can't stop your liver dumping glucose if it is triggered to do so by low levels. It is what our livers do, and it keeps us alive in times of fasting and between meals/overnight. In normal healthy people this still happens, but the pancreas jumps in and secretes insulin to balance out the livers's efforts, keeping glucose levels stable, and at the same time tells the liver to stop dumping. This system is regulated by hormones (glycogen, cortisol and human growth hormones.)

In diabetics, this well regulated system breaks down. The liver and other cells are insulin resistant, so when the liver dumps from its stores, the insulin secreted by the pancreas can't do its job. The end result is the dumped glucose takes much longer to clear and the liver will keep dumping.
There could also be other factors such as a worn out pancreas that doesn't produce enough insulin, or even wonky hormones.

Does that help?
Thanks for the info - I was hoping that by going a bit more seriously at IF I could get a breakthrough on what has been a very, very long plateau regarding weight loss - I also saw an increased Hba1C result at my last review ( although from 35 to 38, I am not concerned at all) its just that I really want to shift the last 10-12 pounds - going to try a longer fast, then if not getting results may have to accept that like a number of people here it seems that IF don't suit me - I would love to understand the mechanism for nothing else other than curiosity !
 
Hi @Element137 - interested to read your latest experiment, because I found exactly the same response. I did daily fasts recently for 10 days straight, 1st-10th October, eating only evening meal, though I continued with tea/coffee/water as normal. My BS levels were raised at every test, sometimes by as much as 2mmol/L. Previously my rise had been around 0.5-0.8mmol/L. This was totally the opposite of what I was trying to achieve, and I stopped the fasts, and returned to my two meals a day from 11th October onwards. What I find even worse - is that my numbers have remained higher, still in the 6s, whereas previously I had always been in the low-medium 5s. My meals were no different from those I usually eat - it's very disconcerting when you haven't a clue why things have gone awry.
This is very similar to my results - frustrating as I had hoped for better results - I have over a years worth of data from testing- very stable/almost predictable results - then IF and start to see big swings.
 
Just for context - I have measured three times a day for over a year - One month on IF and my average BG level is up around 15%, I also measure Standard Deviation ( yes, very sad,I know, I like data ) as a measure of variation in my results, one month on IF SD increased 26% - so in summary - higher and more variable - absolutely not what I was intending to achieve ! -
 
Thanks - I was thinking of extending the fast for longer period to see if that brings about the desired effect - may try it next - I have been surprised by how easy it is to fast - especially just continuing from overnight until evening meal - just really disappointed with the results so far.
just wanted to check, as people have various definitions of "fasting", what were you taking in during your fast period?
 
Couple of cups of coffee ( with very small amount of milk ) and water, that's it.
Sounds great.. have fun with the extended.. watch out for hunger towards 48 hours it can be quite nasty the first time..it might be easier if you can be asleep at that time..
 
Thanks for the info - I was hoping that by going a bit more seriously at IF I could get a breakthrough on what has been a very, very long plateau regarding weight loss - I also saw an increased Hba1C result at my last review ( although from 35 to 38, I am not concerned at all) its just that I really want to shift the last 10-12 pounds - going to try a longer fast, then if not getting results may have to accept that like a number of people here it seems that IF don't suit me - I would love to understand the mechanism for nothing else other than curiosity !

Good luck, I hope it works for you.
 
Back
Top