Fasting/Ketosis for cognition

[TwoHighways]

I’m confused here. Can’t you just eat a keto diet to maintain the ketosis without fasting?

I typically don’t hit more than 2 mmol levels of ketones when doing my normal daily routine (unless I test immediately after working out), but then again, I’m not following a classic 4:1 ketogenic diet either. I do wonder if you just consumed fat as your only macro for a few days if you’d hit the same level of ketosis that you would if you had simply fasted over the same amount of time. Fat is just fat whether it’s exogenous or endogenous, right? Or is there something else going on during total nutrient deprivation that ramps up ketosis to a level you can’t reach just by eating fat? Heck, when your ketone levels rise to around 7 mmol, they create an insulin response to inhibit further ketogenesis and protect from the development of ketoacidosis.

I also wonder just how much protein one would have to consume to be kicked out of ketosis (generally defined as registering 0.5 mmol or greater). If protein was that insulinogenic, it would inhibit the very gluconeogenesis necessary to convert gluconeogenic amino acids and glycerol to glucose. There’s clearly a balancing act between insulin and glucagon at play. So yeah, probably why I’m not over 2 mmol often eating what I eat, but I’m not big on chasing a number just for the sake of chasing a number, unless I am fasting, and then it’s mostly for curiosity. The main takeaway is to keep insulin levels sufficiently low enough to always be producing a relevant amount of ketones.

---

Members don't see this ad.

 

[AnonymousDoctorGuyPerson]

Off-topic but man if my diet required having to know the mmols of something, oof. More power to yall I guess.

I also do intermittent fasting for the concentration benefits (on a 18:6 schedule). From my personal experience I am far more capable of getting work done in the morning and afternoon now. I could never try Keto, though - just farrr too difficult as a vegetarian especially as someone trying to gain weight. Also still iffy on the long-term benefits/ramifications of such a diet.

 

[dr_kateb]

Off-topic but man if my diet required having to know the mmols of something, oof. More power to yall I guess.

I also do intermittent fasting for the concentration benefits (on a 18:6 schedule). From my personal experience I am far more capable of getting work done in the morning and afternoon now. I could never try Keto, though - just farrr too difficult as a vegetarian especially as someone trying to gain weight. Also still iffy on the long-term benefits/ramifications of such a diet.

Still doable. Load up on avocados and peanut butter.

 

[deleted480308]

It's not lack of self control that keeps people from not going 36 hours without food. I'm a psychiatrist and I'm more than a little worried that doctors-to-be believe it's healthy to go one month without food.

I did a 40 day religious water only fast. For a slightly overweight guy with no comorbities it went fine. Agreed not inherently healthy though

 

[AnonymousDoctorGuyPerson]

Still doable. Load up on avocados and peanut butter.

I mean, tbf my diet is currently a LOT of peanut butter atm (PB+Blueberries+Greek Yogurt has been my lunch for 18 years and I still look forward to it every day lmao) but Keto is work. It's already hard enough for me to eat enough in my 6hr window to gain weight, if I need to start restricting my diet to essentially no carbs hahaha yeah it just won't last. I know me well enough. Plus my SO bakes a lot and I can never resist a nibble.

 

[kb1900]

Show me a high performance athlete that fasts during competition or training.

 

[Matthew9Thirtyfive]

Show me a high performance athlete that fasts during competition or training.

There are plenty of Muslim athletes that train and compete during Ramadan. Kadijah Diggs won the 2016 Sweetwater Super Sprint (half mile swim, 12 mile bike ride, 5k run) while fasting.

 

[NITRAS]

There are plenty of Muslim athletes that train and compete during Ramadan. Kadijah Diggs won the 2016 Sweetwater Super Sprint (half mile swim, 12 mile bike ride, 5k run) while fasting.

Not trying to be picky, but fasting sun up to sun down is a lot different than what others here are talking about. And just because they won, doesn’t mean it was optimal.

I find the point of fasting to do better on tests to be silly. . . But I don’t have any data other than it just sounds stupid. . . Which understandably is anecdotal not meaningful to the discussion. I’m NPO for an EGD right now and I am not focused. I’m irritable. My wife and my children also compete for the hangry awards. So I try to avoid anything resembling fasting.

 

[Matthew9Thirtyfive]

Not trying to be picky, but fasting sun up to sun down is a lot different than what others here are talking about. And just because they won, doesn’t mean it was optimal.

Sounds like you’re trying to be picky.

 

[TwoHighways]

Show me a high performance athlete that fasts during competition or training.

Oh FFS, no one here is arguing that fasting is optimal for glycolytic activities. And who among us is actually an elite athlete/earning a living through athletic competition? Your run of the mill relatively sedentary person and weekend warrior would be far better off following a 16:8, 18:6, or OMAD with an occasional extended fast than the typical three meals a day that is pervasive in our society.

 

[odyssey2]

Speak of the devil, an article on intermittent fasting just came out in JAMA Internal Medicine. Looks like it had no metabolic benefit and was actually associated with muscle loss:

Effects of Time-Restricted Eating on Weight Loss and Other Parameters in Patients With Overweight and Obesity

This randomized clinical trial examines the effect of 16:8-hour time-restricted eating on weight loss and metabolic risk markers.

jamanetwork.com

 

[deleted480308]

Oh FFS, no one here is arguing that fasting is optimal for glycolytic activities. And who among us is actually an elite athlete/earning a living through athletic competition? Your run of the mill relatively sedentary person and weekend warrior would be far better off following a 16:8, 18:6, or OMAD with an occasional extended fast than the typical three meals a day that is pervasive in our society.

I don’t think that statement is proven.

if you said, “the avg american would be healthier with less calorie intake and a way they can achieve that is literally skipping meals”, we might get closer to an agreement

 

[TwoHighways]

Speak of the devil, an article on intermittent fasting just came out in JAMA Internal Medicine. Looks like it had no metabolic benefit and was actually associated with muscle loss:

Effects of Time-Restricted Eating on Weight Loss and Other Parameters in Patients With Overweight and Obesity

This randomized clinical trial examines the effect of 16:8-hour time-restricted eating on weight loss and metabolic risk markers.

jamanetwork.com

Did you even read the study, or just the abstract? Subject compliance was essentially on the honor code as far as I can tell. Can’t believe such a poor study was even conducted, much less published regardless of the results. Control for calories/macros and put the subjects in a metabolic ward for a month, but that would be far too costly and hence, never conducted.

 

[odyssey2]

Did you even read the study, or just the abstract? Subject compliance was essentially on the honor code as far as I can tell. Can’t believe such a poor study was even conducted, much less published regardless of the results. Control for calories/macros and put the subjects in a metabolic ward for a month, but that would be far too costly and hence, never conducted.

This is the inherent problem with nutrition studies, it’s very difficult to put the subjects in a controlled environment in an ethical and cost effective manner, so we need to rely on self-reported studies more than is ideal. But it’s better than no data, and definitely better than the the anecdotal broscience that fills the void for these studies.

 

[TwoHighways]

This is the inherent problem with nutrition studies, it’s very difficult to put the subjects in a controlled environment in an ethical and cost effective manner, so we need to rely on self-reported studies more than is ideal. But it’s better than no data, and definitely better than the the anecdotal broscience that fills the void for these studies.

Data in animal models is pretty convincing, from c elegans to mammals. If something is evolutionarily conserved over a billion years of evolution, might be something to take note of...

 

[AnonymousDoctorGuyPerson]

Speak of the devil, an article on intermittent fasting just came out in JAMA Internal Medicine. Looks like it had no metabolic benefit and was actually associated with muscle loss:

Effects of Time-Restricted Eating on Weight Loss and Other Parameters in Patients With Overweight and Obesity

This randomized clinical trial examines the effect of 16:8-hour time-restricted eating on weight loss and metabolic risk markers.

jamanetwork.com

I mean, I don't think anyone here is arguing IF in itself makes you lose weight - at the end of the day, it's still about calories in / calories out. Better off looking at calorie-restriction compliance in IF dieting vs control. I imagine it's easier for people to maintain a lower calorie diet via IF than your standard eating throughout the day.

 

[ExcitatorySynapse]

I am amazed by all of you that can manage IF. I lift (with sets aimed towards hypertrophy) and do HIIT 4x a week and if I don't eat regularly or enough, I have horrendous mood swings that really mess with me as well as impaired concentration. I also have difficulty sleeping if I restrict too heavily. I also can't intake a large amount of food at once. No idea what's wrong with me.

I'm at a normal weight, though I want to get leaner and thinner. The thinnest I ever was when I ate like 1k calories a day but I was on medication that had appetite supression as a substantial side effect and I lost a ton of muscle mass...

 

[kb1900]

Oh FFS, no one here is arguing that fasting is optimal for glycolytic activities. And who among us is actually an elite athlete/earning a living through athletic competition? Your run of the mill relatively sedentary person and weekend warrior would be far better off following a 16:8, 18:6, or OMAD with an occasional extended fast than the typical three meals a day that is pervasive in our society.

That is not true at all

 

[kb1900]

Did you even read the study, or just the abstract? Subject compliance was essentially on the honor code as far as I can tell. Can’t believe such a poor study was even conducted, much less published regardless of the results. Control for calories/macros and put the subjects in a metabolic ward for a month, but that would be far too costly and hence, never conducted.

Data in animal models is pretty convincing, from c elegans to mammals. If something is evolutionarily conserved over a billion years of evolution, might be something to take note of...

Putting these two side by side just for emphasis. You are completely biased

 

[Matthew9Thirtyfive]

Refrain from personally attacking or flaming other users.

 

[Bloobury]

I know I get pretty delirious if I don’t eat for a couple days, but I guess that’s cause I’m skinny.

****, I get delirious if I don't eat at least every 12 hours. 😀

 

[Mass Effect]

Sounds like you’re trying to be picky.

I don't think that was picky. The poster made a legitimate point - you can't really compare a person eating one meal a day (fasting from sun up to sun down) to someone fasting for a week or a month, as is stated in this thread.

 

[Matthew9Thirtyfive]

I don't think that was picky. The poster made a legitimate point - you can't really compare a person eating one meal a day (fasting from sun up to sun down) to someone fasting for a week or a month, as is stated in this thread.

The poster I responded to asked for an example of a high performance athlete competing or winning while fasting. They didn’t say for a month. So my answer completely satisfied that criteria.

 

[Mass Effect]

The poster I responded to asked for an example of a high performance athlete competing or winning while fasting. They didn’t say for a month. So my answer completely satisfied that criteria.

Yes it did. You did answer the question. But the poster's response to you was that it wasn't the same and I think that's fair, not picky.

 

[Matthew9Thirtyfive]

Yes it did. You did answer the question. But the poster's response to you was that it wasn't the same and I think that's fair, not picky.

He’s saying it’s not the same as something I wasn’t talking about. So yes, I guess that’s fair. But it wasn’t relevant to the question being asked.

 

[TwoHighways]

Life is better oxidizing fat.

A ketogenic diet extends longevity and healthspan in adult mice - PMC

Calorie restriction, without malnutrition, has been shown to increase lifespan and is associated with a shift away from glycolysis toward beta-oxidation. The objective of this study was to mimic this metabolic shift using low-carbohydrate diets and ...

www.ncbi.nlm.nih.gov

 

[AnonymousDoctorGuyPerson]

Life is better oxidizing fat.

A ketogenic diet extends longevity and healthspan in adult mice - PMC

Calorie restriction, without malnutrition, has been shown to increase lifespan and is associated with a shift away from glycolysis toward beta-oxidation. The objective of this study was to mimic this metabolic shift using low-carbohydrate diets and ...

www.ncbi.nlm.nih.gov

By observation in humans, the longest-lived with the lowest rates of age-related diseases such as dementia is usually found in populations that consume some variant of a Mediterranean diet no?

Suppose we can check-in on all the strict Keto-ers in 100 years.