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Fasting Affects the Brain

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Re: Fasting Affects the Brain

#21

Post by Angostura »

istjohn wrote: post #9

I wonder how these findings can be reconciled with the research on the importance of breakfast for school children. There are obvious differences between the two issues, but nevertheless when I think about how to apply these insights, they seem to conflict, and I'm not sure how to resolve those conflicts. Edit: The biggest difference is age, but conventional wisdom says adults, too, should eat a good breakfast before…

There is really no good evidence that breakfast is "the most important meal of the day", despite what folk wisdom and cereal advertising say. For many people it can easily be skipped.

Re: Fasting Affects the Brain

#22

Post by brink »

throwaway123x2 wrote: post #13
Zaak wrote: post #11

Fasting is a periodic religious observance for me. The main effect I have noticed is increased irritability, but then I've never done cognitive tests while fasting.

That might be from the caffeine withdrawals. I'm trying it wihtout caffeine at all this year, and it's been great.

Espresso has no calories

Re: Fasting Affects the Brain

#23

Post by shanehoban »

everdev wrote: post #14
hashberry wrote: post #4

> And that’s what we’re finding in lab animals — the brain and body actually perform better during fasting. In the case of the brain, cognitive function, learning, memory, and alertness are all increased by fasting. I find this to be true whenever I fast for 12+ hours. It feels like I'm on a drug. It's strange to realize how not eating can be good for you. Fun trivia: the longest a human went without food is 382 days…

Yeah, it feels like getting a "second wind" when exercising. Getting there can be brutal though as my mind and body feel weak and it's hard for me to do any highly cognitive tasks. But after my body accepts it I feel "in the zone" and I don't want to eat and disrupt the feeling. I've never gone longer than 18hrs though.

I'm not a doctor or anything but my own interpretation of this affect is that you are depleting your glucose stores, and when you reach ketosis, you once again have energy to burn.

https://en.wikipedia.org/wiki/Ketosis

Re: Fasting Affects the Brain

#24

Post by magnamerc »

hashberry wrote: post #4

> And that’s what we’re finding in lab animals — the brain and body actually perform better during fasting. In the case of the brain, cognitive function, learning, memory, and alertness are all increased by fasting. I find this to be true whenever I fast for 12+ hours. It feels like I'm on a drug. It's strange to realize how not eating can be good for you. Fun trivia: the longest a human went without food is 382 days…

I've done 7 day water fasts (I try to do them quarterly, or bi-annually) and I find by day three I'm full of energy to the point where I have a hard time sleeping. I'm also way more productive during those 7 days. The only thing that tends to suffer is my weight lifting. I drop in strength a tiny bit, but not nearly as much as you'd expect. I also drop about 5-10 lbs in mass, with about half of that coming from water. Almost no lean muscle loss as far as I can tell. In fact, I always look shredded after the fast. I just ease back in with keto for a week or two, then back to low carb diet.

Re: Fasting Affects the Brain

#25

Post by wastedhours »

hashberry wrote: post #4

> And that’s what we’re finding in lab animals — the brain and body actually perform better during fasting. In the case of the brain, cognitive function, learning, memory, and alertness are all increased by fasting. I find this to be true whenever I fast for 12+ hours. It feels like I'm on a drug. It's strange to realize how not eating can be good for you. Fun trivia: the longest a human went without food is 382 days…

> I find this to be true whenever I fast for 12+ hours. It feels like I'm on a drug.

Totally this - when I was suffering with anorexia, in the early days where I was skipping meals all the time and burning fat, I felt amazing. Literally, "skipping down the streets because I had so much energy" amazing.

Just remember to eat afterwards or you'll f* yourself up. Please.

Re: Fasting Affects the Brain

#26

Post by Tharkun »

brink wrote: post #22
throwaway123x2 wrote: post #13

Earlier quoted context omitted.

That might be from the caffeine withdrawals. I'm trying it wihtout caffeine at all this year, and it's been great.

Espresso has no calories

Grandparent is talking about religious fasting, not a diet. It's likely not about calories.

Re: Fasting Affects the Brain

#27

Post by wyldfire »

mcfunk wrote: post #20
coldtea wrote: post #15

Earlier quoted context omitted.

> Highly recommend the book "The Complete Guide to Fasting" by Dr. Jason Fung. Such books and doctors, promoting this or that diet, heavily cherry-pick from research papers, they don't reflect the scientific consensus on the matter.

I'll be interested to see where the scientific consensus is in 10 years. I think the evidence is very much on the side of the hormonal theory of obesity and fasting, especially given the monumental failure of the "calories in calories out" model.

> especially given the monumental failure of the "calories in calories out" model.

Can you explain this in more detail? CICO seems like it might oversimplify things but it always seemed like a really sane basis for helping shape your diet. If you need to lose weight, you should plan meals to create a calorie deficit. But yes, I would not be surprised to learn that fasting on day X and consuming double your normal calories on day X+1 are not equivalent.

The description of CICO as a "monumental failure" sounds like there's substantial evidence to the contrary -- can you share more info?

Re: Fasting Affects the Brain

#28

Post by ianstallings »

hashberry wrote: post #4

> And that’s what we’re finding in lab animals — the brain and body actually perform better during fasting. In the case of the brain, cognitive function, learning, memory, and alertness are all increased by fasting. I find this to be true whenever I fast for 12+ hours. It feels like I'm on a drug. It's strange to realize how not eating can be good for you. Fun trivia: the longest a human went without food is 382 days…

I was very skeptical of fasting for quite a while, but over winter I was on a contract with a guy that did intermittent fasting and his particular schedule had him eating after 3pm. The guy was like a machine. Just this sense of urgency in his work that was incredible to watch. He accomplished so much more than the other guys in the same position. I'm sure part of that was his own character and his work ethic, but when I talked to him he attributed a lot of it to his fasting. Turns out he's probably correct.

Re: Fasting Affects the Brain

#29

Post by magnamerc »

istjohn wrote: post #9

I wonder how these findings can be reconciled with the research on the importance of breakfast for school children. There are obvious differences between the two issues, but nevertheless when I think about how to apply these insights, they seem to conflict, and I'm not sure how to resolve those conflicts. Edit: The biggest difference is age, but conventional wisdom says adults, too, should eat a good breakfast before…

If you want to ace your LSAT, you're better off getting a good nights sleep and writing the exam fasted. Sleep is way more important than anything else when it comes to memory recall. Also, you should study with a particular type of perfume, and then write the exam with that same perfume. That'll also help memory recall. Breakfast is probably the worst meal of the day, in terms of metabolic health, which is why I haven't regularly had breakfast in over a decade.

Re: Fasting Affects the Brain

#30

Post by rossenberg79 »

I stopped doing fasts because even though I did notice a boost to my productivity, most of it was due to not having to stop in the middle of the day to eat or waste time thinking about eating. In terms of cognitive benefits, going for a run for 30 minutes in the morning still seemed far superior.
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