Welcome to The Fast Diet › The official Fast forums › Body › Benefits and side effects › Body Temperature
This topic contains 15 replies, has 14 voices, and was last updated by Fasterplease 4 months ago.
Viewing 16 posts - 1 through 16 (of 16 total)
22 Aug 13
Has anyone experienced a raise in body temperature, especially on fast days?
23 Aug 13
yes, I have experienced it too…not just on fast days but others days as well. The thermometer reading is around 99F. It seems to come on and off. Am sure its not a flu because there are no other symptoms. Not sure why it happens. Any guesses?
I’m hoping that the body temp is an indication of my body burning fat.. and creating more heat.. 😉
Agree it isn’t a consistant rise in temperature.
I used to be a cold and shivery person .. happily wearing a fleece jumper in 20+ºC even when active.
Having lost quite a lot of fat off my upper back which was I thought what I used for insulation purposes I find this rise in temp quite surprising.
24 Aug 13
I also have felt slightly feverish on fast days, like my body’s thermostat is out of sorts. Wondering what causes this.
I thought it was due to burning fat…but you would expect many others on this forum to notice it too. I read the book and its not mentioned there either. so I am a little confused 🙂
28 Aug 13
Actually I have been feeling cooler since starting to fast. I live in a super hot climate and have been able to set the thermostat 2 degrees F warmer than it was. I thought it was all the water I’ve been drinking, that perhaps I was dehydrated before.
Husband has had it. It seems to have settled now.
5 Feb 14
Like mynameisrio, I’ve felt chilly on my fasting days. I attribute it to having fewer calories to burn, because I don’t experience this until mid afternoon. I live in a cold climate so I pile on the layers in the afternoon. Interestingly, after eating “supper” on those days, I often have to peel layers off.
I have also noticed I am much colder this winter than I was last year, although its nowhere near as cold outside as it was last year! I put it down to all the Tamoxifen leaving my system and the lost of a lot of blubber.
But apparently shivering is good for losing weight 😀
25 Mar 14
But it is still an unknown reaction to the fast right? I also felt feverish today (second day of fast this week),my hands were cold at work but my head felt too warm, now that I just had dinner I’m feeling a little better. I hope it is not the flu !
27 Mar 14
Just guessing with this post.
I believe peristalsis plays a role in feeling cold. Peristalsis is the wave like motion the stomach makes when mixing contents of the stomach into a ball before passing to the intestinal tract. My understanding is that the friction of this action cause some heat. After periods of time it triggers sensitivity signals that co inside with eating and sleeping behavior. In this is reason why we sometimes get sleepy after after lunch, very sleepy hours after dinner.
So when we start fasting There is less friction. It’s an illusion though , the heart regulates the body temp. However our coping mechanisms are not being signaled.
What I do is try to do something similar to friction like moderate activity if I’m feeling cold. I haven’t figured it out , because too much activity on an empty stomach makes me have hunger pangs.
I’ve been trying practice other strategies to take advantage an empty stomach. Like mornings of 50 calories where in take dried fruits and nuts with a glass of antioxidants. And some moderate exercise to poke my metabolism out of ‘sleeping metabolism. Followed by more antioxidant rich caffienated teas shortly after to help feel full.
4 Apr 14
The burn phase, I call it. Usually happens on my 36 hour fast. Fantastic feeling to feel your body actually burning off the weight/fat.
14 May 16
I am wonder if anyone else has experienced this? I have had waves of warmth on some of the fasting days and, like Grinham, it doesn’t feel bad.
I have looked around for information ascribing that feeling to something biological and came up empty.
19 May 16
I get it as well. Actually its a really easy way of telling when I enter ketosis. I water fast and as soon as I get a warm stomach I know Im in ketosis. Confirmed this with a keto meter. I posted a question about this on Peter Attia’s blog and it is a known phenomenon. You have to burn a lot of calories just to access the calories stored in the fat cells.
28 Mar 17
I am on my first day of fasting, i have split the calories in two meals, breakfast and dinner, with an apple at lunch. By 17 00 i began to feel feverish and also feeling like my body temperature is slightly up. A little lightheaded too. If this is a sign i am burning fat, i would be surprised that the diet worked in such a short period of time.
3 Mar 20
I have an hypothesis which may be true in a few cases, though probably there are other things going on in most cases.
Overheating in the body is commonly associated with liver damage, and 60% of people in the western world have some damage to their liver (even if they don’t drink processed food, fizzy drinks etc). My theory is that in a state of deep repair the body will start cleaning up the liver.
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