Fasting Can Regenerate Your Immune System

Health, Fitness, Food, Insurance, Longevity, Diets,...
Post Reply
jacob
Site Admin
Posts: 15906
Joined: Fri Jun 28, 2013 8:38 pm
Location: USA, Zone 5b, Koppen Dfa, Elev. 620ft, Walkscore 77
Contact:

Re: Fasting Can Regenerate Your Immune System

Post by jacob »

Jeez peeps. I was kidding!!! # https://en.wikipedia.org/wiki/Poe%27s_law

The longest I ever fasted was 24 or 36 hrs or so. After that I was so hungry I binged on tzatziki and pancakes (very dumb idea!) and proceeded to puke it all back up in short order. Also, people around me thought I was being anorexic. Pretty stupid approach... so goes various experiments twenty+ years ago. If I do it again, I'll be smarter about it.

BRUTE
Posts: 3797
Joined: Sat Dec 26, 2015 5:20 pm

Re: Fasting Can Regenerate Your Immune System

Post by BRUTE »

daylen wrote:
Thu Feb 15, 2018 4:50 pm
Question: What is the relationship between how long you can fast and body weight? .. what about body fat percentage?
there isn't a lot of research, but there's a little, and a lot of anecdotes.

there exists a study of a morbidly obese human male fasting for about 400 days straight, ending up at a regular weight. various anecdotes confirm that fat/obese humans can relatively easily fast for days to weeks on end without getting hungry. there exist anecdotes that humans who have low/regular body fat can't fast much more than a day or two before they start losing muscle mass (though water retention in muscle cells would be interesting here, would it all just come back after rehydrating?) and start getting antsy.

brute has read that there's a limit as to how much fat can be extracted from a cell of human body fat during any given day. brute forgets but the number has been estimated to be around 20-40kcal/lbs of fat/day, if he remembers correctly. so a 200lbs human male at 10% body fat would be able to metabolize around 400-800kcal per day.

this seems to fit the anecdotes relatively well.

7Wannabe5
Posts: 9369
Joined: Fri Oct 18, 2013 9:03 am

Re: Fasting Can Regenerate Your Immune System

Post by 7Wannabe5 »

@BRUTE:

That fact about daily limit to fat extraction is interesting. I will tell my cuckoo sister about that the next time she is at bottom healthy BMI and obsessing about the fat remaining on her thighs. I seriously believe that her extreme dieting practices contribute to her poor mental health incidents.

BRUTE
Posts: 3797
Joined: Sat Dec 26, 2015 5:20 pm

Re: Fasting Can Regenerate Your Immune System

Post by BRUTE »

brute has talked about this before on this forum, but there are also various hormone levels necessary to mobilize different fat cells. this can vary genetically and depends on many factors like location of the fat cell, general "fat equilibrium" of a person, many hormone levels (adrenaline, insulin, cortisol, leptin, ghrelin, probably more).

for example, pre-menopausal human females will typically have more butt, thigh, and breast fat than males. males will mostly put on belly fat. after menopause, women also tend to gain belly fat. various ethnic groups tend to put on fat at different rates or in different spots. some east asian humans will develop late-stage diabetes but not gain much fat. blessing or curse? others are genetically very susceptible to gaining fat overall, or in specific places - thus the cliche of women of various ethnicities possessing superior posteriors. (brute cannot lie).

given that 7Wannabe5 has mentioned her posterior various times on this forum, and that her (bird?) sister probably shares a high percentage of genes with 7Wannabe5, brute would surmise it could be very difficult for said sister to reduce thigh fat dramatically. genetics.

User avatar
Sclass
Posts: 2791
Joined: Tue Jul 10, 2012 5:15 pm
Location: Orange County, CA

Re: Fasting Can Regenerate Your Immune System

Post by Sclass »

Finished up at about 3 1/2 days. Blood pressure is holding at normal levels. Simply amazing for me. I noticed my surgical scars softened up a bit too. Ten years later they’ve only grown and become more inflamed. This is the first improvement I’ve seen.

I’ve eaten two light meals and one normal one. Got diarrhea. Seems like this is common. Perhaps I changed up my microbiome. It feels like I’ve done a week of antibiotics.

I hope the change in blood pressure lasts for awhile.

Pretty shocking results. Thanks for sharing.

BRUTE
Posts: 3797
Joined: Sat Dec 26, 2015 5:20 pm

Re: Fasting Can Regenerate Your Immune System

Post by BRUTE »

scars, low inflammation, diarrhea, all common. brute also noticed he wouldn't get sunburn while fasting. not sure if good or bad.

NPV
Posts: 188
Joined: Fri Dec 06, 2013 9:41 am

Re: Fasting Can Regenerate Your Immune System

Post by NPV »

Inspired by this research, this topic and examples such as sclass, I am now about 64 hours into a fast (the goal is 72 hours as this is what the research recommends to reset the immune system). The only things I have been consuming are ginger brew (boiled water, ginger, only the water is consumed) and minerals (iodine, zinc, pink Himalayan salt). I have mostly been on some combination of IF and lowish carb paleo / bulletproof diet and occasional keto for a few years but have not tried fasting for more than 24-30 hours before.

Overall, I feel pretty good. No significant hunger at any point during the ~64 hours as long as I don't think about / look at food - other than habitual drive to go to the kitchen and get something to chew. There was a cliff about ~24 hours in when I was struggling to think fast enough to maintain a professional phone conversation - although I have also changed time zones by a few hours that day. After going to sleep soon after and waking up the next day I have been feeling fine. A bit less physical energy than usual and a bit less focus but also oddly a bit more mental clarity on open-ended thinking as long as I don't try too much to direct it.

I could see myself doing this occasionally - how occasionally depends on the key concern which is muscle mass loss. I often travel for work during the week and get some meal allowance so if muscle loss was not a concern I could even engineer a pretty nice "freegan" diet basically eating during the work week and fasting on the weekends.

What is recommended as the first meal to break the fast? Something like an avocado and some greek yoghurt to get a mix of nutrients and add some healthy gut bacteria while not overloading on carbs and hence prolonging ketosis for a few extra hours?

BRUTE
Posts: 3797
Joined: Sat Dec 26, 2015 5:20 pm

Re: Fasting Can Regenerate Your Immune System

Post by BRUTE »

NPV wrote:
Sat Feb 17, 2018 6:29 pm
What is recommended as the first meal to break the fast? Something like an avocado and some greek yoghurt to get a mix of nutrients and add some healthy gut bacteria while not overloading on carbs and hence prolonging ketosis for a few extra hours?
humans recommend all kinds of stuff from "keeping it light" to "fruit" and "bla bla microbiome blah".

brute has broken a 10 day fast with sausages and 6 eggs, cooked in butter, with a ton of shredded cheese. full? yes. problem? no.

taemoo
Posts: 43
Joined: Wed Oct 13, 2010 3:59 am
Location: Madison, WI

Re: Fasting Can Regenerate Your Immune System

Post by taemoo »

I've been trying fasting since the new year and feeling really good about it. Tried a 7 day, 2 day and a 3 day. I come out of the fast into intermittent fasting/keto, getting great results on weight loss. Probably do a 3 day fast once a month going forward until goal weight. I break the fast primarily with bone broth egg drop soup because I really enjoy it and makes me full. Along with the soup I've eaten avocados, broccoli, bacon, kimchi, sausage, pecans and did not have any issues.

User avatar
Sclass
Posts: 2791
Joined: Tue Jul 10, 2012 5:15 pm
Location: Orange County, CA

Re: Fasting Can Regenerate Your Immune System

Post by Sclass »

I broke my fast with a couple of cups of low sodium chicken bone broth. A soft boiled egg. An orange. One standard matzo cracker with a smear of unsalted peanut natural peanut butter on it.

The next meal I had boiled cabbage and a small cup of rice and some boiled chicken. A couple of Argentine shrimp. Asparagus.

The absolute great news is my blood pressure is holding at 120/80. I’m back on regular foods. I’ve reduced sugar and simple carbs and replaced the gap with meat, veggies, eggs and nuts. Hope the effects last.

BRUTE
Posts: 3797
Joined: Sat Dec 26, 2015 5:20 pm

Re: Fasting Can Regenerate Your Immune System

Post by BRUTE »

take that, science

NPV
Posts: 188
Joined: Fri Dec 06, 2013 9:41 am

Re: Fasting Can Regenerate Your Immune System

Post by NPV »

I ended up breaking my fast at about 75 hour mark with some yoghurt and dried coconut. And when I say "some", I mean about a kilo of yoghurt and what was probably a full sized coconut before it was dried.

Overall, I would say the fast was interesting in the sense that it was much longer than what I have done before and it was interesting to understand empirically that my body and mind can do this.

I have not felt any magical results (or any big inconvenience). It looks like I have lost a fair chunk of muscle, I don't remember my arms looking that small since I started lifting weights at 16 years old. Hopefully my immune system got the lauded reset and I got a lot of longevity and cancer risk reduction benefits because I don't think I am repeating this any time soon without a clear specific reason to.

BRUTE
Posts: 3797
Joined: Sat Dec 26, 2015 5:20 pm

Re: Fasting Can Regenerate Your Immune System

Post by BRUTE »

NPV wrote:
Wed Feb 21, 2018 3:41 am
I ended up breaking my fast at about 75 hour mark [..] It looks like I have lost a fair chunk of muscle, I don't remember my arms looking that small since I started lifting weights at 16 years old.
highly unlikely that any significant amount of muscle was lost in 3 days. what probably happened is that NPV's muscles stopped retaining as much water due to the fast. once he starts eating again, he'll probably gain all the bulk back within a day or two.

brute often loses and re-gains 7-10lbs when doing a multi-day fast (of which 3 days is just the beginning). it's not all muscle/fat, most of it is shifts in water retention.

BRUTE
Posts: 3797
Joined: Sat Dec 26, 2015 5:20 pm

Re: Fasting Can Regenerate Your Immune System

Post by BRUTE »

Augustus wrote:
Wed Feb 21, 2018 9:16 pm
the Fast Mimicking Diet is supposed to prevent muscle loss and bone density loss, both of which happen during water fasting.
muscle and bone density loss probably occur after a certain period of fasting. but does Augustus really plan to fast 1 week out of every month or so, in order for it to make a difference? from what brute has seen, there are pretty much no negative long-term side effects from water fasting until around 3 days.

losing a few grams of muscle and bone density by water fasting one week every few months is probably easily made up for by occasional weight bearing exercise.

brute is just not that convinced of the negative side effects of "a little fasting" (vs. starvation). there seems to be almost no research. the few studies brute has seen seem very dubious.

one of the difficulties in this area is that measuring "lean body mass" or "bone density" is pretty expensive, time-consuming and difficult. plus, it's not even clear that all lean body mass or all bone density is good. for example, many humans have anecdotally reported losing scars on fasts. humans that lose a lot of fat also have to lose skin, in order to prevent sagging - in which case the loss of lean body mass is good. in the case of bone density, brute has seen studies that besides an overall increase or decrease in bone density, it can also shift around, for example reducing density in the arms and shifting it to the legs. good or bad? depends if that humans is a boxer or a kickboxer.

plus, there is a bit of lean body mass in every fat cell - thus fat loss can lead to loss of lean body mass, but not in a negative way. both muscle and fat cells store lots of water - is that water being measured when lean body mass/fat mass are DEXA scanned?

Kriegsspiel
Posts: 952
Joined: Fri Aug 03, 2012 9:05 pm

Re: Fasting Can Regenerate Your Immune System

Post by Kriegsspiel »

If you are concerned about losing the least amount of muscle during your 5 day fast, it's logical to eat protein (the most muscle-sparing macronutrient) instead of fat and carb.

pukingRainbows
Posts: 131
Joined: Sat Mar 21, 2015 5:56 pm

Re: Fasting Can Regenerate Your Immune System

Post by pukingRainbows »

Thanks for this thread!
It inspired me to fast the first Monday of every month.
I started last week on Monday and went until Wednesday morning. 56 hours, just water, nothing else.

It was interesting to examine my relationship to food. I missed food and the act of eating like I would miss a dear friend. It was more emotional than physical. On the second day I felt pretty empty and at certain points that life was a joyless, grey existence. The experience definitely put me in a unique mindset: solemn and contemplative. I can see how fasting can have a spiritual aspect. I do feel changed from it.

I slept quite well and woke up feeling great on both mornings. Also, I usually get withdrawal headaches for days or even a week if I stop drinking my daily coffee but when fasting I only experienced a slight headache the first night and that's it.

It was a good experience and I'm looking forward to next month as well. My goal is 72 hours.

Solvent
Posts: 233
Joined: Wed Mar 04, 2015 3:04 pm
Location: กรุงเทพมหานคร
Contact:

Re: Fasting Can Regenerate Your Immune System

Post by Solvent »

I tried out fasting in December. I was suspending eating from the evening meal on Sunday (and Wednesday), through to the evening meal on Monday (and Thursday). So roughly two 22-hour fasts. I got sick late December and didn’t really feel up to modifying my habits through until about now, so I’m back to trying fasting again. Seriously doubt the fasting was connected to sickness, firstly it wasn’t intense fasting, secondly the sickness seemed to be allergies/respiratory (sore throat, air in this city is awful).

Anyway, my question to you all is – how do you mix fasting with exercise? I can imagine exercising on an empty stomach I guess, but I feel like I would need to placate my gut afterwards. Do you just not exercise on fasting days/during extended fasts? Do you time exercise to be right before you break fast? Do you find it not to be a problem?

Also, on picking up fasting again (today), I couldn’t understand anything at all in my French class. My teacher actually asked me if I needed coffee. In fact, I had just had coffee prior to the class but it didn’t seem to help. I hope the dim-wittedness doesn’t continue; I suspect it maybe just because I’m not accustomed to the practice of fasting yet.

enigmaT120
Posts: 1240
Joined: Thu Feb 12, 2015 2:14 pm
Location: Falls City, OR

Re: Fasting Can Regenerate Your Immune System

Post by enigmaT120 »

The exercise question probably depends on the person. I fasted yesterday and won't eat today until around noon, but I still did my 10 mile morning bike ride to catch the bus the rest of the way to work. It doesn't bug me and I'm not hungry yet. I've never noticed any change in my blood sugar levels regardless of what or how little I eat. I will eat before I ride 18 more miles home.

BRUTE
Posts: 3797
Joined: Sat Dec 26, 2015 5:20 pm

Re: Fasting Can Regenerate Your Immune System

Post by BRUTE »

the "weakness" or "low energy" from fasting can take days to materialize. last time he fasted for ~7 days, brute continued his weight lifting routine throughout. only at day 3 did he feel any impact of the fast at all, and on day 7 he actually felt pretty weak and had to go down in weights. it is unlikely that glycogen reserves in the muscles would manifest within <72h fast, unless one were to run a marathon or do CrossFit daily.

Kriegsspiel
Posts: 952
Joined: Fri Aug 03, 2012 9:05 pm

Re: Fasting Can Regenerate Your Immune System

Post by Kriegsspiel »

Code: Select all

Comparison of bodily fuels in a 150 lb man with 22% bodyfat
Tissue 					Average weight (lbs) 		Caloric worth (kcal)
Adipose tissue triglyceride 		33 				135,000
Muscle protein 				13 				24,000
Carbohydrate stores
 Muscle glycogen (normal) 		00.25 				480
 Liver glycogen 			00.5 				280
 Blood glucose 				00.04 				80
 Total carbohydrate stores 		00.8 				840 
 
 Source: “Textbook of Biochemistry with Clinical Correlations 4th ed.” Ed. Thomas M. Devlin.
Wiley-Liss, 1997.
The main point to take from this chart is that carbohydrate stores are minimal in
comparison to protein and fat, sufficient to sustain roughly one day’s worth of energy. Although
stored protein could conceivably fuel the body for far longer than carbohydrate, excessive protein
losses will eventually cause death. This leaves adipose tissue as the primary depot for long term
energy storage (2). The average person has enough energy stored as bodyfat to exist for weeks or
19
energy storage (2). The average person has enough energy stored as bodyfat to exist for weeks or
months without food intake and obese individuals have been fasted for periods of up to one year.

- The Ketogenic Diet by McDonald

Post Reply