5 ms·

The surprising cause of fasting's regenerative powers

47 points by pseudolus 2y ago

Shadowed_ 2y ago
> After mice had abstained from food Yeah, right, mice abstained from food. Mice don't abstain from food. You didn't feed them!
- delichon 2y ago
  Nice catch. This is a step worse than hiding the actor as in "the mice were sacrificed." It flips the whole script as in "the mice (heroically) sacrificed themselves (for science)."
reportgunner 2y ago
So what's the surprising cause ? I couldn't find it after skimming the article twice.
- roughsquare 2y ago
  [flagged]
- thefz 2y ago
  > Breaking a fast carries more health benefits than the fasting itself, a study in mice shows1. After mice had abstained from food, stem cells surged to repair damage in their intestines — but only when the mice were tucking into their chow again, the study found Literally the first paragraph
  - reportgunner 2y ago
    I still don't see the cause. Eating is the cause ? How is that surprising ?
    - taeric 2y ago
      You can have a finding without knowing the underlying cause. As an easy example, see gravity. In this case, the presumption is that it isn't necessarily the eating? It is specifically the sequence of fasting -> eating. As just eating with no fasting involved does not trigger this. Similarly, just fasting did not get this response, but it primed the mice so that their next meal did.
      - reportgunner 2y ago
        Yeah the title is "The surprising cause of fasting’s regenerative powers", I wanted to know about the cause. The article doesn't mention it. Clickbait article.
        taeric 2y ago
        Apologies on missing this. Fair. I was interested in the link and the idea that there is something there, even if we don't know what.
- jtbayly 2y ago
  The surprise is that the benefit isn’t gained until you start eating again. It’s not during the fast that good things happen, apparently.
  - mizzao 2y ago
    The article actually seemed to suggest that eating after fasting increased the chance of "precancerous growths", which seems like "bad things".
    - StephenSmith 2y ago
      And then refuted that with a different study at the end. Weird.
- dzsquared 2y ago
  tldr; positively impacts stem cells making them more effective at repairing damage
  - azinman2 2y ago
    Which also lead to tumors as polyamines are involved in cellular division.
  - zihotki 2y ago
    .. in mice.
begueradj 2y ago
I read all sort of contradictory "scientific facts" about this subject. By the end of the day, listening and observing your body will provide you the right answer.
- anotherhue 2y ago
  Sure...but an interesting recent-ish development is that you're not only listening to your body, but to a enormous microbiome that is also signalling you towards its own ends (it's sugar, they always want sugar). Here's a paper that talks about the pathway: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4367209/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4367209/
  - rajnathani 2y ago
    Not really about the sugar point. At times people crave savory or something high starch+fat based. For instance, little kids generally tend to crave for very sweet things but at times prefer something like pizza or pasta over something sweet (this is based on a personal second-hand observations). This is also the case for humans, for example during cheat days that people don't simply eat sweets (for example Dwayne Johnson finishing up something like 12 pizzas as one of the things on his cheat days).
- lm28469 2y ago
  Everyone is different that's for sure. I haven't eaten breakfast since I'm a teen and I mostly eat one meal a day for the last 10+ years Everybody talks shit about fasting but nobody even bat an eye at "you have to eat three times a day, every day, at the same time, everything else is obviously wrong", which is at least as ridiculous
  - 082349872349872 2y ago
    Around here, the five mealtimes are morning-meal, 9 o'clock snack, midday-meal, 4 o'clock snack, and evening-meal. On the other hand, I've been in a resort where they announced "merienda will be served between X and Y o'clock", which scandalised my local friends, who wondered aloud who'd ever heard of such sacrilege as eating merienda according to a clock and not your stomach. My impression of historical practice is that people who had to go work in groups, in fields (or later in factories), tended to hew to traditional mealtimes. (there's a nice discussion somewhere on HN about how you don't want to stay in the fields between noon and one, or the "noonday witch" will get you...) However, those who could afford it simply ate whenever they felt like (in at least two asian countries I know, it's considered a faux pas if there is ever a moment during the day when the main table doesn't have some sort of food on it). The story I heard is that in the western context it was Louis XIV* who instituted mealtimes for rich as well as poor: his court was so large and so elaborate that logistics demanded the kitchen no longer be open, as it had been under previous monarchs, for courtiers to swing by at any hour they felt like grabbing some grub. True, or "Just So"? * later, in the waning days of Austria-Hungary, the protocol at court dinners was that one did not continue eating dessert after the Emperor had finished with his. Of course, he had also been served first, so at some precedence level it must've always been a throw of the dice, whether one would even get served any Kaiserschmarrn before it was time to down forks.
sl-1 2y ago
Interesting, but I would be careful to generalize from mice studies
Amorymeltzer 2y ago
The actual paper (paywall): https://www.nature.com/articles/s41586-024-07840-z https://www.nature.com/articles/s41586-024-07840-z
bilsbie 2y ago
I tried one meal per day for three weeks and I had to quit because my heart would start racing after my meal. Really bizarre. I couldn’t find any information.
- naasking 2y ago
  Interesting, increased heart rate after eating is not uncommon [1]. Could be a sudden influx of glucose after fasting kicking a lot metabolic functions into gear. [1] https://www.healthtoday.com/be-healthy/heart-health/why-does-heart-race-after-eating https://www.healthtoday.com/be-healthy/heart-health/why-does...
- TimSchumann 2y ago
  I haven't had that experience, but I usually do longer fasts. My go to for this would be electrolyte levels, which can vary heavily depending on water intake, diet, exercise, supplementation, etc. Here's some journal articles I found based on a quick search. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1364615/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1364615/ https://pubmed.ncbi.nlm.nih.gov/8777833/ https://pubmed.ncbi.nlm.nih.gov/8777833/ https://link.springer.com/article/10.1007/s002280050682 https://link.springer.com/article/10.1007/s002280050682 Be interested to hear if something in one of those pops out at you.
- mactavish88 2y ago
  Were you supplementing with electrolytes while fasting? Don’t have any studies at hand right now, but fasting apparently causes you to quickly lose fluid and electrolytes. I recently started doing 5:2 fasting and noticed on the day after fasting that I tend to get bouts of pretty bad orthostatic hypotension. Supplementing with a zero-calorie electrolyte on fasting days and the day after helped mitigate this.
- gadders 2y ago
  I lost 15kg by tracking calories and eating one meal a day in the evening. The rest of the day was filled with coffee and an apple for lunch. I've pretty much stuck to one meal a day now. Lunch is still something light, like a protein bar or an apple. The only time I really eat breakfast now is if I'm on holiday and it's included...
tu7001 2y ago
Are there any other studies in the topic except on mice?
- TimSchumann 2y ago
  Generally the answer is 'no' to that question. Medical ethics tends to prohibit it, especially in a clinical setting. It's seen as doing harm to the patients, which physicians tend to frown on. I've even heard of some papers on fasting, retrospectives -- which I think aren't technically studies but an aggregation and analysis of patient data, collected from events that have already happened, which patients voluntarily undertook -- that were banned from journals because the results may have 'encouraged harmful behavior.' Don't have any sources on that and it's a memory from like 6-8 years ago though.
mactavish88 2y ago
For those potentially concerned about cancer risk from breaking fasts, from the article itself: > Researchers should always be concerned about anything that could cause cancer, but Valter Longo, a biogerontologist at the University of Southern California in Los Angeles, says that mice with the tweaked genes were “almost doomed to get cancer”, and that the slight rise in risk found in this study might not be applicable more broadly. For example, he points to a study he published in 2015 that found a 45% reduction in abnormal cell and tissue growth in mice that fasted compared with animals that did not. The mice that developed precancerous growths were genetically modified to be prone to such cancerous development.
- TimSchumann 2y ago
  Yeah, all the research I've read says that fasting is actually preventative when it comes to cancer -- and possibly assists with starving out cancer cells during treatment of the disease.
TimSchumann 2y ago
Interesting post to wake up to when I'm 7 days into a fast. Glad to be getting back into extended fasting, sad that I, again, have the body type that makes it somewhat of a requirement health wise.
deleted 2y ago
[deleted]

47 points by pseudolus 2y ago

> After mice had abstained from food Yeah, right, mice abstained from food. Mice don't abstain from food. You didn't feed them!

delichon 2y ago
Nice catch. This is a step worse than hiding the actor as in "the mice were sacrificed." It flips the whole script as in "the mice (heroically) sacrificed themselves (for science)."

reportgunner 2y ago

So what's the surprising cause ? I couldn't find it after skimming the article twice.

roughsquare 2y ago
[flagged]
thefz 2y ago
> Breaking a fast carries more health benefits than the fasting itself, a study in mice shows1. After mice had abstained from food, stem cells surged to repair damage in their intestines — but only when the mice were tucking into their chow again, the study found Literally the first paragraph
- reportgunner 2y ago
  I still don't see the cause. Eating is the cause ? How is that surprising ?
  - taeric 2y ago
    You can have a finding without knowing the underlying cause. As an easy example, see gravity. In this case, the presumption is that it isn't necessarily the eating? It is specifically the sequence of fasting -> eating. As just eating with no fasting involved does not trigger this. Similarly, just fasting did not get this response, but it primed the mice so that their next meal did.
    - reportgunner 2y ago
      Yeah the title is "The surprising cause of fasting’s regenerative powers", I wanted to know about the cause. The article doesn't mention it. Clickbait article.
      - taeric 2y ago
        Apologies on missing this. Fair. I was interested in the link and the idea that there is something there, even if we don't know what.
jtbayly 2y ago
The surprise is that the benefit isn’t gained until you start eating again. It’s not during the fast that good things happen, apparently.
- mizzao 2y ago
  The article actually seemed to suggest that eating after fasting increased the chance of "precancerous growths", which seems like "bad things".
  - StephenSmith 2y ago
    And then refuted that with a different study at the end. Weird.
dzsquared 2y ago
tldr; positively impacts stem cells making them more effective at repairing damage
- azinman2 2y ago
  Which also lead to tumors as polyamines are involved in cellular division.
- zihotki 2y ago
  .. in mice.

begueradj 2y ago

I read all sort of contradictory "scientific facts" about this subject. By the end of the day, listening and observing your body will provide you the right answer.

anotherhue 2y ago
Sure...but an interesting recent-ish development is that you're not only listening to your body, but to a enormous microbiome that is also signalling you towards its own ends (it's sugar, they always want sugar). Here's a paper that talks about the pathway: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4367209/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4367209/
- rajnathani 2y ago
  Not really about the sugar point. At times people crave savory or something high starch+fat based. For instance, little kids generally tend to crave for very sweet things but at times prefer something like pizza or pasta over something sweet (this is based on a personal second-hand observations). This is also the case for humans, for example during cheat days that people don't simply eat sweets (for example Dwayne Johnson finishing up something like 12 pizzas as one of the things on his cheat days).
lm28469 2y ago
Everyone is different that's for sure. I haven't eaten breakfast since I'm a teen and I mostly eat one meal a day for the last 10+ years Everybody talks shit about fasting but nobody even bat an eye at "you have to eat three times a day, every day, at the same time, everything else is obviously wrong", which is at least as ridiculous
- 082349872349872 2y ago
  Around here, the five mealtimes are morning-meal, 9 o'clock snack, midday-meal, 4 o'clock snack, and evening-meal. On the other hand, I've been in a resort where they announced "merienda will be served between X and Y o'clock", which scandalised my local friends, who wondered aloud who'd ever heard of such sacrilege as eating merienda according to a clock and not your stomach. My impression of historical practice is that people who had to go work in groups, in fields (or later in factories), tended to hew to traditional mealtimes. (there's a nice discussion somewhere on HN about how you don't want to stay in the fields between noon and one, or the "noonday witch" will get you...) However, those who could afford it simply ate whenever they felt like (in at least two asian countries I know, it's considered a faux pas if there is ever a moment during the day when the main table doesn't have some sort of food on it). The story I heard is that in the western context it was Louis XIV* who instituted mealtimes for rich as well as poor: his court was so large and so elaborate that logistics demanded the kitchen no longer be open, as it had been under previous monarchs, for courtiers to swing by at any hour they felt like grabbing some grub. True, or "Just So"? * later, in the waning days of Austria-Hungary, the protocol at court dinners was that one did not continue eating dessert after the Emperor had finished with his. Of course, he had also been served first, so at some precedence level it must've always been a throw of the dice, whether one would even get served any Kaiserschmarrn before it was time to down forks.

sl-1 2y ago

Interesting, but I would be careful to generalize from mice studies

Amorymeltzer 2y ago

The actual paper (paywall): https://www.nature.com/articles/s41586-024-07840-z https://www.nature.com/articles/s41586-024-07840-z

bilsbie 2y ago

I tried one meal per day for three weeks and I had to quit because my heart would start racing after my meal. Really bizarre. I couldn’t find any information.

naasking 2y ago
Interesting, increased heart rate after eating is not uncommon [1]. Could be a sudden influx of glucose after fasting kicking a lot metabolic functions into gear. [1] https://www.healthtoday.com/be-healthy/heart-health/why-does-heart-race-after-eating https://www.healthtoday.com/be-healthy/heart-health/why-does...
TimSchumann 2y ago
I haven't had that experience, but I usually do longer fasts. My go to for this would be electrolyte levels, which can vary heavily depending on water intake, diet, exercise, supplementation, etc. Here's some journal articles I found based on a quick search. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1364615/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1364615/ https://pubmed.ncbi.nlm.nih.gov/8777833/ https://pubmed.ncbi.nlm.nih.gov/8777833/ https://link.springer.com/article/10.1007/s002280050682 https://link.springer.com/article/10.1007/s002280050682 Be interested to hear if something in one of those pops out at you.
mactavish88 2y ago
Were you supplementing with electrolytes while fasting? Don’t have any studies at hand right now, but fasting apparently causes you to quickly lose fluid and electrolytes. I recently started doing 5:2 fasting and noticed on the day after fasting that I tend to get bouts of pretty bad orthostatic hypotension. Supplementing with a zero-calorie electrolyte on fasting days and the day after helped mitigate this.
gadders 2y ago
I lost 15kg by tracking calories and eating one meal a day in the evening. The rest of the day was filled with coffee and an apple for lunch. I've pretty much stuck to one meal a day now. Lunch is still something light, like a protein bar or an apple. The only time I really eat breakfast now is if I'm on holiday and it's included...

tu7001 2y ago

Are there any other studies in the topic except on mice?

TimSchumann 2y ago
Generally the answer is 'no' to that question. Medical ethics tends to prohibit it, especially in a clinical setting. It's seen as doing harm to the patients, which physicians tend to frown on. I've even heard of some papers on fasting, retrospectives -- which I think aren't technically studies but an aggregation and analysis of patient data, collected from events that have already happened, which patients voluntarily undertook -- that were banned from journals because the results may have 'encouraged harmful behavior.' Don't have any sources on that and it's a memory from like 6-8 years ago though.

mactavish88 2y ago

For those potentially concerned about cancer risk from breaking fasts, from the article itself: > Researchers should always be concerned about anything that could cause cancer, but Valter Longo, a biogerontologist at the University of Southern California in Los Angeles, says that mice with the tweaked genes were “almost doomed to get cancer”, and that the slight rise in risk found in this study might not be applicable more broadly. For example, he points to a study he published in 2015 that found a 45% reduction in abnormal cell and tissue growth in mice that fasted compared with animals that did not. The mice that developed precancerous growths were genetically modified to be prone to such cancerous development.

TimSchumann 2y ago
Yeah, all the research I've read says that fasting is actually preventative when it comes to cancer -- and possibly assists with starving out cancer cells during treatment of the disease.

TimSchumann 2y ago

Interesting post to wake up to when I'm 7 days into a fast. Glad to be getting back into extended fasting, sad that I, again, have the body type that makes it somewhat of a requirement health wise.

deleted 2y ago

[deleted]