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Intermittent fasting increases hippocampal neurogenesis in mice

pubmed.ncbi.nlm.nih.gov

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Re: Intermittent fasting increases hippocampal neurogenesis in mice

#111

Post by ckemere »

jmcgough wrote: post #108
ckemere wrote: post #107

Earlier quoted context omitted.

It's worth noting that there's some controversy about the extent of adult neurogenesis in humans. If it exists it's likely at the scale of a few neurons per day. Whether or not that means that increasing it by fasting is important is unclear.

Yeah, a 2018 UCSF study was unable to find any adult neurogenesis in humans, so it's still a controversial subject when it comes to humans. Even if we had confidence that adult neurogenesis occurs in humans, we can't really expose humans to a stimuli, kill them and then do a BrdU stain, so it's difficult to know how well any rat study translates over to humans.

The early evidence in humans was based on radioisotopes present in the atmosphere after atomic tests. You could diffentiate neurons in people's brains (after they died) if they had been born before the 1940s.

Re: Intermittent fasting increases hippocampal neurogenesis in mice

#112

Post by _wldu »

m3kw9 wrote: post #110

They considered 12hr a fast. So finishing dinner at around 7 and eating at 7am next day is considered a fast? Easier than I thought about what a fast would be like

Yes, It is. It's so common, in fact, that it has a name... breakfast. Break the fast.

Re: Intermittent fasting increases hippocampal neurogenesis in mice

#113

Post by jml7c5 »

Very important to note that the non-fasting mice were significantly less heavy:

>Compared to AL [ad libitum, "at one's pleasure"] mice, IF12 [12 hour fast], IF16 [16 hour fast], and EOD [24 hour fast] tamice demonstrated significantly lower average body weight after 3 months of IF (Data not shown).

So this could be due to lower overall caloric intake.

Re: Intermittent fasting increases hippocampal neurogenesis in mice

#114

Post by jml7c5 »

hourislate wrote: post #14
Nabati wrote: post #9

16 hours for a mouse is probably equivalent to fasting multiple days for humans.

A mouse starves to death in 48 hours. I have gone 12 days without food (water fast) and was not even close to starvation. Probably could have gone another few weeks before I expired. I would say 16 hours for a mouse is probably more like 7 plus days without food for a Human.

>A mouse starves to death in 48 hours.

Can you provide a citation for this?

Re: Intermittent fasting increases hippocampal neurogenesis in mice

#115

Post by brudgers »

ckemere wrote: post #105
SubiculumCode wrote: post #90

Earlier quoted context omitted.

I don't think that we need to apply a value to neurogenesis and I do not think the authors do either except that it seems to be correlated with other quote good behaviors like exercise. Presumably neurogenesis is occurring all the time and is restricted to a small set of regions in the brain and the new neurons form in just those very strict set of regions. Those neurons are not moving to the neocortex, just a few mi…

I think the primary "function" attributed to adult hippocampal neurogenesis is improved memory. But the parent comment is unfair insofar as scientists don't randomly chose to food deprive or "vivisect" animals because they think it's intrinsically fun. Running these experiments requires a huge amount of annoying busy work that I can't imagine anyone choosing to do without being paid or having some other motive. In pa…

Sorry for not being clear. I don’t think people starve and vivisect mice for fun. And I agree that there being money in it is much of the moment to moment motivation for the moment by moment steps that are necessary for it to happen. Putting a happy p-hacked face on the process is how ordinary people rationalize what they are doing as something other than what it is.

The business of cutting apart animals and looking at the insides claim revealed knowledge isn’t new. The Romans called it “haruspicy” and also built wealthy bureaucratic institutions in service of narratives useful to the powerful.

Contemporary interest in fasting research is helpful to those who find advantage in moralizing upon obesity. Intermittent fasting is a virtue reserved for those with food security. It’s attractive to people whose socio-economic status insures that going hungry is a choice and a display of will power. Not weakness. The conclusion that it makes such people smarter is self serving.

The preponderance of health evidence is that starvation is detrimental to human health and creates long term cognitive problems. But lab mice are an industrial product and labs are industrial institutions and the money keeps flowing so long as the results are acceptable to those providing it. That’s the way it has been for millennia.

Re: Intermittent fasting increases hippocampal neurogenesis in mice

#116

Post by SenorTibbs »

faeyanpiraat wrote: post #89
acituan wrote: post #73

Details to pay attention to; - It is not stated if the diets are isocaloric or hypocaloric; probably because it wasn't measured. Timing restrictions and calorie restrictions are two different stressors on the body, and all else being equal stress is positively correlated with neurodegenerative effects. It might as well be only isocaloric intermittent fasting is indicative of BDNF increase and hippocampal neurogenesis…

"stress is positively correlated with neurodegenerative effects" Can you provide some references to this?

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4806285/

[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3196277/

Re: Intermittent fasting increases hippocampal neurogenesis in mice

#117

Post by ip26 »

TuringNYC wrote: post #77
csomar wrote: post #58

Earlier quoted context omitted.

If 12H is considered IF, then I have been intermittently fasting for the last 4-5 years.

From everything I've read, it is on a spectrum. 12 is on the spectrum, but supposedly the longer the period the more marked the effects. I'm not sure at what point the curve flattens and drops off. 12 is better than, say, 8 or 6 (e.g., snacking at night). Curious how your experience compares to your pre-IF state 5+yrs ago?

There's a point it becomes destructive. I tend to ignore hunger, and I find after 20 hours or so my mood nosedives, I get shaky, generally things go south quickly and even if I eat I'm still a wreck for a while. 12-16hrs is probably the sweet spot from my experience.

BMI 18-19 for reference.

Re: Intermittent fasting increases hippocampal neurogenesis in mice

#118

Post by hrbf »

mrfusion wrote: post #42
loceng wrote: post #37

Earlier quoted context omitted.

Switch when you eat. So 8am to 2pm or 4pm eating time.

That’s certainly an idea. The nice thing now is that it’s effortless. I don’t feel like eating after dinner and I don’t feel hungry in the morning. You’d think there would be something calorie free to make coffee taste good.

There is: high quality beans.

Re: Intermittent fasting increases hippocampal neurogenesis in mice

#120

Post by TuringNYC »

ip26 wrote: post #117
TuringNYC wrote: post #77

Earlier quoted context omitted.

From everything I've read, it is on a spectrum. 12 is on the spectrum, but supposedly the longer the period the more marked the effects. I'm not sure at what point the curve flattens and drops off. 12 is better than, say, 8 or 6 (e.g., snacking at night). Curious how your experience compares to your pre-IF state 5+yrs ago?

There's a point it becomes destructive. I tend to ignore hunger, and I find after 20 hours or so my mood nosedives, I get shaky, generally things go south quickly and even if I eat I'm still a wreck for a while. 12-16hrs is probably the sweet spot from my experience. BMI 18-19 for reference.

Your IF experience sounds hard, is IF worth it for you?

Would you mind sharing your BMI from before IF? Also curious if you feel IF is better than the alternatives (e.g., Keto, which for me has been the "easiest" of the effective diets)

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