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Fasting Affects the Brain

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Re: Fasting Affects the Brain

#121

Post by busymom0 »

ravenstine wrote: post #34

I sometimes intermittently fast for 24 hour periods, but recently I've switched to skipping breakfast, which effectively works out to be a 17 hour fast for me if I eat dinner at 6pm and have lunch at 12pm. Everyone says it's the most important meal of the day, but I haven't found convincing evidence of this(especially that which isn't sponsored by grain and sugar producers), and not having a huge insulin spike at the…

> The only negative effect I'm having is that my sex drive has plummeted to near-zero.

Are you eating enough healthy fats? (whole eggs, avocados etc). Also maybe look into ZMA (zinc, magnesium aspartate, and vitamin B6) supplementation or at least get your blood work done to see if you are low on anything. A lot of people have lower testosterone levels and sex drive due to low zinc.

Re: Fasting Affects the Brain

#122

Post by coldtea »

kazinator wrote: post #114
coldtea wrote: post #112

Earlier quoted context omitted.

> "eat a diet and time your eating in a way that promotes healthy hormone balance and use of fat as energy" is a silver bullet If it promises you to lose weight without limiting your calorie intake (e.g. have your weight loss cake and eat it too), then yes. > but "use our magic equations based on state of the art info from 1958 to calculate your daily food needs and all your food and exercise as numbers and if your e…

Some people don't want to lose "weight", but "fat" (often specifically "subcutaneous fat", often from some specific body area). If you're already very fit and lean, but have some stubborn fat around the "love handle" area or elsewhere, "eat less" doesn't cut it any more. Sure you can reduce that area, but not completely, and while the rest of you turns into an ugly skeleton.

>Some people don't want to lose "weight", but "fat" (often specifically "subcutaneous fat", often from some specific body area).

The latter people are then delluded, surgery aside, you can't lose targeted fat from a specific body area. You lose fat across your body AND from that area, or you don't lose fat.

At best, you can trait that area and build some muscle next to the fat.

Re: Fasting Affects the Brain

#123

Post by avinium »

ravenstine wrote: post #60
drekembemutombo wrote: post #47

Earlier quoted context omitted.

If it works for you, sure. Interesting, I often eat a big but healthy breakfast and then eat nothing for the rest of the day, and that works really well for me.

Everyone's a bit different and have their own preferences. I just think that the idea that everyone must eat breakfast(or any meal), and eat it promptly, is bogus. A better general rule, I think, is that people should only eat when they're actually hungry . That could be in the morning or any time. I have an empty stomach in the morning(waking up around 6pm), but I don't usually feel hunger until between 10:30a and 1…

You’re right, but the problem is that most people have forgotten what real hunger feels like. They confuse “hormone dependence” from years of eating carb heavy meals with actual hunger.

The easiest way to retrain yourself is to stick to simple rules about when to eat (and what to eat).

Re: Fasting Affects the Brain

#124

Post by HNLurker2 »

ravenstine wrote: post #34

I sometimes intermittently fast for 24 hour periods, but recently I've switched to skipping breakfast, which effectively works out to be a 17 hour fast for me if I eat dinner at 6pm and have lunch at 12pm. Everyone says it's the most important meal of the day, but I haven't found convincing evidence of this(especially that which isn't sponsored by grain and sugar producers), and not having a huge insulin spike at the…

"I fast for greater physical and mental efficiency" Plato

Re: Fasting Affects the Brain

#125

Post by HNLurker2 »

ohaideredevs wrote: post #79
magnamerc wrote: post #24

Earlier quoted context omitted.

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…

Being hungry increases alertness. This is discussed in "The Willpower Instinct", in the context of keeping you from sleeping well. It's natural - the body knows it needs to find food, so it makes you hyper until you do, negatively affecting the ability to get essential sleep. So, there is nothing weird about what you are experiencing - it's like wanting to get air when you are under water. Doesn't make it a good way…

>Being hungry increases alertness. This is discussed in "The Willpower Instinct",

Being hungry decreases your will power, as said in the book. That also means refusing offered food affects your will power

Re: Fasting Affects the Brain

#126

Post by SketchySeaBeast »

beagle3 wrote: post #116
SketchySeaBeast wrote: post #111

Earlier quoted context omitted.

You're not describing a failure of the calories in/out, you're describing a failure to measure the caloric requirements correctly. How do you find that? Eat less, measure your weight. Titrate as required. Worked for me, works for many.

Why do you call it ci/co then? Call it “weight in / weight out” - it better describes your system, in which calories (and their elusive measurement) is a red herring.

Because in order to determine how much I eat I'm going to calculate it with calories.

Re: Fasting Affects the Brain

#127

Post by beagle3 »

SketchySeaBeast wrote: post #126
beagle3 wrote: post #116

Earlier quoted context omitted.

Why do you call it ci/co then? Call it “weight in / weight out” - it better describes your system, in which calories (and their elusive measurement) is a red herring.

Because in order to determine how much I eat I'm going to calculate it with calories.

“Eat less” is fine, but reference to calories is mostly useless given that your ability to measure them going in or going out has an overall 50% error.

The fallacy is that those numbers are anything but a very vague approximation.

Re: Fasting Affects the Brain

#128

Post by Jommi »

bbryant wrote: post #74
ravenstine wrote: post #34

I sometimes intermittently fast for 24 hour periods, but recently I've switched to skipping breakfast, which effectively works out to be a 17 hour fast for me if I eat dinner at 6pm and have lunch at 12pm. Everyone says it's the most important meal of the day, but I haven't found convincing evidence of this(especially that which isn't sponsored by grain and sugar producers), and not having a huge insulin spike at the…

FWIW, saw this study pass the NYT radar a few weeks back. https://www.nytimes.com/2019/04/22/well/eat/skipping-breakfa...

Very interesting. This is just a correlational study, and is limited to 40-65 year old americans.

But it stills strikes for a need of more investigation.

Re: Fasting Affects the Brain

#129

Post by copperx »

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.

Some people might just be built differently.

Take me, for example. Ever since I was a teen I have fasted until midday most days (for lack of time) and it significantly affects my cognition. I start feeling irritable at about 10am and unable to concentrate because of feelings of hunger, stomach grumbling, and slight shakiness.

I am a teacher now, and I can tell how my cognition is doing every morning depending on my performance in the classroom. I find that I often mumble and screw up my grammar while lecturing if I haven't had breakfast. I am not calm, but I would not say I feel "energized." I am clearly anxious. My anxiety gradually increases until I have lunch. Then I feel calm and with the ability to think.

It might be genetic. My grandmother was known to be unable to function without breakfast. My mother was the same way.

Re: Fasting Affects the Brain

#130

Post by rossenberg79 »

phonypc wrote: post #104
rossenberg79 wrote: post #102

Earlier quoted context omitted.

What if you are low on fat stores?

Define low. Unless you're a competitive body builder on show day, you've probably got enough fat to cover a few weeks worth of energy needs.

12% is not that low, but hardly weeks worth of energy needs.
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