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Fasting boosts stem cells’ regenerative capacity (2018)

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Re: Fasting boosts stem cells’ regenerative capacity (2018)

#71

Post by pid-1 »

TimSchumann wrote: post #62
milchek wrote: post #59

Earlier quoted context omitted.

I also question if 7 days is safe for most. I don't recall exactly when and a quick search now yields a lot of random gimmicky fasting product sales sites with blog posts written to generate traffic that aren't scientific enough, but I do recall that there is a point (after 72 hours?) where your body starts breaking down muscle and that prolonged fasting is dangerous as your organs get hit next? Perhaps someone here…

I lost zero noticeable lean muscle mass on my 60 day fast, at least no more than I would have sitting on the couch doing nothing. There's just not a metabolic pathway for breaking down muscle/organ tissue for energy when you have adequate fat stores. We would have died off as a species a long time ago if that were the case. In the grand scheme of things, if you have the body fat, 7 days is nothing for a fast. Edit: T…

Did you exercise or work during this period?

Re: Fasting boosts stem cells’ regenerative capacity (2018)

#72

Post by travisporter »

SemanticStrengh wrote: post #60
lm28469 wrote: post #50

Earlier quoted context omitted.

That's not how it works at all. Not drinking water will damage/kill you real fast, not eating food on the other hand is pretty safe for most people. The longest fast was ~380 days [0] If you have some fat (75% of westerners are heavily overweight or obese) you can easily fast on water only for weeks, of course you're not going to be able to exercise heavily every day or run a marathon. But if you're an overweight off…

1) there are tons of substances the body can't make out of nothing/lipids. 2) there are tons of substances the body can't make efficiently with no food, which leads to metabolism/health deficits. and no it's not just vitamins and electrolytes LOL it's much more complex and diverse than that. 3) even if we assume in an ideal world, that the person who fast is able to supplement ALL the useful things and yet not take a…

What are bioenergetics biomarkers and apoptotic biomarkers? Google doesn’t give me a reliable source

Re: Fasting boosts stem cells’ regenerative capacity (2018)

#73

Post by cassianoleal »

LittleBox wrote: post #54
cassianoleal wrote: post #34

Earlier quoted context omitted.

> eat protein throughout their fast too Aren't these contradictory? If you eat (protein or otherwise) you're not fasting.

I think they misspoke and what they meant to say was that bodybuilders use a zero/low carb diet, in which case their statement holds true.

Their whole argument was around body builders not losing fat when fasting, so if you're right, this is just irrelevant. No one expects people to lose fat when they're not caloric restricted.

Re: Fasting boosts stem cells’ regenerative capacity (2018)

#74

Post by lm28469 »

SemanticStrengh wrote: post #60
lm28469 wrote: post #50

Earlier quoted context omitted.

That's not how it works at all. Not drinking water will damage/kill you real fast, not eating food on the other hand is pretty safe for most people. The longest fast was ~380 days [0] If you have some fat (75% of westerners are heavily overweight or obese) you can easily fast on water only for weeks, of course you're not going to be able to exercise heavily every day or run a marathon. But if you're an overweight off…

1) there are tons of substances the body can't make out of nothing/lipids. 2) there are tons of substances the body can't make efficiently with no food, which leads to metabolism/health deficits. and no it's not just vitamins and electrolytes LOL it's much more complex and diverse than that. 3) even if we assume in an ideal world, that the person who fast is able to supplement ALL the useful things and yet not take a…

You went from "This guy should be dead" after 30 days of fasting to "this one guy died 25 years after a one year fast".

All I'm saying is that you were wrong. The human body can take much more than you explained in your first comment. You won't die nor fall unconscious and "5-7 days max" isn't anywhere close to the limit

Re: Fasting boosts stem cells’ regenerative capacity (2018)

#75

Post by lm28469 »

egeozcan wrote: post #55
TimSchumann wrote: post #36

Earlier quoted context omitted.

I really think a 7 day fast should be 'mandatory reading' as far as life experience goes. You learn a lot about yourself. Also echo the mental clarity side of fasting. The weight loss was great, but how I felt was even better. The crazy thing is, if you can get to 7 days, anything past that is just mental and you can go as long as you have the body fat to sustain the fast, provided you're keeping an eye on your elect…

I'm not sure if starting something like a 7-day fast without medical supervision is a good idea, and I'm also not sure if any medical professional would allow you to do that, just thinking out loud. Don't you think it's too dangerous to name it essential life experience and recommend it to random people on the internet? I'm really asking, I'm not knowledgeable about this at all, and my questions stem from pure gut fe…

> I'm not sure if starting something like a 7-day fast without medical supervision is a good idea

I'm not sure starting a western diet without medical supervision is a better idea given 75% of the west is overweight or obese. Unless you have medical conditions a 7 days fast is a walk in the park in term of health

Re: Fasting boosts stem cells’ regenerative capacity (2018)

#76

Post by SemanticStrengh »

travisporter wrote: post #72
SemanticStrengh wrote: post #60

Earlier quoted context omitted.

1) there are tons of substances the body can't make out of nothing/lipids. 2) there are tons of substances the body can't make efficiently with no food, which leads to metabolism/health deficits. and no it's not just vitamins and electrolytes LOL it's much more complex and diverse than that. 3) even if we assume in an ideal world, that the person who fast is able to supplement ALL the useful things and yet not take a…

What are bioenergetics biomarkers and apoptotic biomarkers? Google doesn’t give me a reliable source

There are many. For apoptosis induced by mitochondria deficits you look at the level of cytochrome C. But there are others. For oxidative stress, a good indication is the ratio of reduced glutathione (how much of your antioxidants are being used)

for bioenergetics I don't remember the relevant ones although the manifestation is not only molecular, it can be observed (mitochondria respiration rate, uncoupling, etc) maybe this paper can show the relevant ones? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4715336/

Re: Fasting boosts stem cells’ regenerative capacity (2018)

#77

Post by lm28469 »

SemanticStrengh wrote: post #76
travisporter wrote: post #72

Earlier quoted context omitted.

What are bioenergetics biomarkers and apoptotic biomarkers? Google doesn’t give me a reliable source

There are many. For apoptosis induced by mitochondria deficits you look at the level of cytochrome C. But there are others. For oxidative stress, a good indication is the ratio of reduced glutathione (how much of your antioxidants are being used) for bioenergetics I don't remember the relevant ones although the manifestation is not only molecular, it can be observed (mitochondria respiration rate, uncoupling, etc) ma…

Are you comparing fasting to breathing aluminium particles ?

Re: Fasting boosts stem cells’ regenerative capacity (2018)

#78

Post by beagle3 »

lm28469 wrote: post #50
SemanticStrengh wrote: post #42

Earlier quoted context omitted.

This guy should be dead, his body should have digested himself. How can someone not eat anything by his own will for more than a few days ? (5-7 max) you should pass out. Also in the case that were true, let me be clear: No food intake for multiple days is extremely dangerous for your health, it will upregulate autophagy, apoptosis and will break your mitochondria bioenegetics which will explode your oxidative stress…

That's not how it works at all. Not drinking water will damage/kill you real fast, not eating food on the other hand is pretty safe for most people. The longest fast was ~380 days [0] If you have some fat (75% of westerners are heavily overweight or obese) you can easily fast on water only for weeks, of course you're not going to be able to exercise heavily every day or run a marathon. But if you're an overweight off…

You actually should exercise while fasting. When fasting, t he body gets rid of fat, and any muscles that are not essential. Which makes a lot of sense - maintaining muscle costs both protein and energy, even if they aren’t used much.

I did not try to run quickly while fasting, but I did keep doing my 5km 3 times per week, and the gym. Anaerobic was hard and quickly tiring, but aerobic exercise wasn’t really any harder.

A friend did point out that my movement was “more economical” in general - I hardly lifted my feet while running or walking, and a few other things. But I didn’t feel more tired or more strained, except for unaerobics.

Re: Fasting boosts stem cells’ regenerative capacity (2018)

#79

Post by rhinoceraptor »

milchek wrote: post #59
egeozcan wrote: post #55

Earlier quoted context omitted.

I'm not sure if starting something like a 7-day fast without medical supervision is a good idea, and I'm also not sure if any medical professional would allow you to do that, just thinking out loud. Don't you think it's too dangerous to name it essential life experience and recommend it to random people on the internet? I'm really asking, I'm not knowledgeable about this at all, and my questions stem from pure gut fe…

I also question if 7 days is safe for most. I don't recall exactly when and a quick search now yields a lot of random gimmicky fasting product sales sites with blog posts written to generate traffic that aren't scientific enough, but I do recall that there is a point (after 72 hours?) where your body starts breaking down muscle and that prolonged fasting is dangerous as your organs get hit next? Perhaps someone here…

I haven't seen any convincing evidence that significant muscle loss occurs with a 7 day fast. If you get a DEXA scan before and after, you will have lost a lot of "lean body mass" and your muscles will be smaller, but it's only because you lose about 5-10lbs of water weight.

The only major health risk is refeeding syndrome, and even then it's only really notable if you're an alcoholic or have anorexia. If you're otherwise healthy with normal sodium/potassium/etc. intake and you take it slow when refeeding, I don't think it's particularly dangerous. Obviously, talk to your doctor, and it's probably good to get blood work before doing something like this.

Re: Fasting boosts stem cells’ regenerative capacity (2018)

#80

Post by strogonoff »

mahathu wrote: post #69
seer wrote: post #66

Earlier quoted context omitted.

While I’ve done similar fasting myself, with the same wondrous effects you describe, I want to point out that it seems this might be a lot harder to do for young women (in child bearing age). My partner tried to replicate what I did since I was hyping it so much, and failed miserably. Later we learned that the female body reacts much more violently to the lack of calories than male ones, and its a lot harder for them…

I'm kind of doing "one meal per day" right now, not because I'm fasting on purpose but just because I don't enjoy eating (or cooking) more than once in a day. I mean I like to cook but doing it for over an hour every day just becomes a chore. I was under the impression that this was really unhealthy though. My BMI is 19 so I'm close to being underweight. Isn't this unhealthy? Do people fast and not lose weight?

I’m sure many would be quick to jump to numbers on how much you are supposed to consume/burn in a day, but I really don’t think eating too little or too much is by itself an indicator.

The underlying psychological issues and associated stresses is what IMO qualifies as “unhealthy”, in which case corresponding under- or over-eating could result in malnourishment or excess weight[0]. However, in absence of these issues or other factors suppressing your body’s hunger/satiety messaging, not eating some “standard amount” shouldn’t be an issue on its own[1].

I happen to know a person who fasts routinely. In case of that person it doesn’t seem to be motivated by hidden psychological issues (he does not strike me as a person who could be suffering from body dysmorphia/anorexia) but by a conscious health choice. As an example of his logic, recently he got COVID and from his words he “simply” didn’t eat for two days and was right back on his feet feeling great. It’s not my place to question his choices, and I myself try to space meals to spend 14–16 hours without food every day since it seems to leave me feeling better, so it was surprising to hear but not too outlandish. He is not bulky but not skinnier than me either[2].

(I’m not a doctor, but from a cursory check medicine does seem to classify eating disorders as “expressive”, i.e. indicative of underlying issues. I don’t know how medicine treats under-eating without a cause, I certainly hope they don’t try to force-“treat” someone to make them eat at a level medicine considers “normal”.)

[0] For the record, I don’t think one can truly address those root causes just by eating less or more.

[1] In fact IIRC lower metabolic rates have been correlated with longer lifespans, at least in mice and in snails if not in humans.

[2] I’m slightly underweight, and can eat quite a bit without gaining much weight. My sister is similar, and she quickly gets low blood sugar shakes if she doesn’t eat enough. I guess it’s a sign of fast metabolism.

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