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The fact that leptin, not food, restored high-power mode makes me wonder if we could use leptin to increase dieting efficacy. I’ve read that there are limits to how much weight you can lose per week, no matter how much you restrict your caloric intake. Beyond a certain point, your body senses the deficiency and decreases your metabolism. If a person could restrict calories AND receive leptin injections, they could lose weight faster. (note, I am thinking about this in terms of helping the morbidly obese in dire circumstances.)
>if we could use leptin to increase dieting efficacy

it's called a refeed and bodybuilders have been doing it for decades to drop fat while maintaining muscle mass, you don't need leptin injections

some recent studies have backed up the bro science as well

>The researchers reported that 19 participants in the continuous diet group completed the study and lost an average of 9.1 kg furthermore, 17 participants in the intermittent diet group completed the study and lost an average of 14.1 kg (4).Hence, the authors concluded that greater weight and fat loss was achieved in the intermittent diet group (4)

"Beyond a certain point, your body senses the deficiency and decreases your metabolism. "

As far as I'm able to tell this is a myth. There isn't any scientific evidence supporting it, and quite a bit which implies it is impossible - if a body could run itself more efficiently then it would by default. Calorie consumption is necessary to sustain life.

This myth is usually perpetuated by people who believe they are on calorie restricted diets, but who are actually eating more than they think.

This diet trick does exist and it’s called eating eggs. :) The protein and fat in conjunction with leptin are highly satiating and are easier and cheaper to feed than the macros and chemicals individually.
> I’ve read that there are limits to how much weight you can lose per week, no matter how much you restrict your caloric intake.

I've been fasting here and there and I'm down from 130Kg to 98Kg in about 5 months. Apparently your body handles that sense of deficiency better if you fast vs multiple small meals. Something about that large meal letting you experience the "I'm so full" feeling.

There's a study in the NEJM where they tested 3 meals a day vs one. The participants ended up at the same weight at the end, but with smaller waists and less belly fat for one meal a day.

It's all interesting albeit frustrating stuff...

Edit: https://sa1s3.patientpop.com/assets/docs/151222.pdf

I might be remembering the results wrong as I can't find the details in that study, I'm going off this video mainly https://www.youtube.com/watch?v=thgVz3837l0

If I'm wrong about the results it seems the other benefits make it worthwhile anyway, preventing diabetes etc

Weight loss is such a well explored topic with high commercial demand that anything you've thought of has probably already been done. As far as drugs to speed up weight loss there's DNP, which actually works. It's justifiably banned though because it is easy to overdose on and die from overheating. Not a good way to go.

Morbidly obsese can just water fast. /r/fasting on Reddit is full of success stories.

Just use a cheat day. This will help to keep the metabolism up and also psychological, because if you got desire to eat X, just put it on the cheat day list and eat it at that day. (If you keep fulfill your desires at the cheat day regularly, u develop trust in your list, which makes it even more effective).

You shouldn't go under 1 cheat day a week. See 4 hours body book for sources.

There's research in neurodietetics, for example https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3105244/

I can't quite tell how strong each and every paper in the field is, nor would this be the place to do it, but what I recognize as their foundational observation that Holocaust survivors brains were roughly the same size as of normally fed people, while other organs shrunk, is quite striking.

I've noticed that when I'm tired mentally, closing my eyes for a while even if I don't sleep makes me feel better. I wonder if that's related by letting that part of the brain power down for a bit?
It’s leptin rescue for mice in torpor. Likely no applicability to humans.
That seems particularly important. Leptin is naturally released by fat cells, so I wonder how this would have impacted overweight mice, who may have already been naturally releasing this leptin - assuming that's how leptin works.

But also, no one should be fasting and eating nothing - they should make sure they're getting the necessary vitamins and minerals. Taking more leptin could make sense.

I read that the differences between metabolism speeds are nearly insignificant. Is where somewhere I can go to understand more about that? The general understanding between "fast" and "slow" metabolism seems to be a magic used to rationalize anything about the body, while one of my golden rules is to never trust any scale that lacks a base unit.
Yes, Leptin is the reason why cheat meals every 4 days are a win.

Note : i absolutely loved the book of "Tom Venuto - Burn the fat, feed the muscle".

Or they could water fast (under medical supervision). After a couple of days they won't feel the need to eat. They will lose a ton of weight.
This isn't true. Your metabolism does slow down but it never slows down 1 cal per cal of food restriction. You always lose more weight the less you eat.
I don’t understand this obsession with finding secret tricks to dieting. The root problem is the abundance of cheap, overly processed food being advertised to people with a lack of willpower. Until we tackle those core problems, everything is pointless, because finding a workaround means enabling yet more of the bad behaviour.
One time I bonked so hard on a long ride that i lost color vision.

Fastest orange juice i ever drank.

I temporarily lost part of hearing, too. Happend to me after casually biking in a fasted state after attempting a short but steep climb. When I was at the top, I made a break just to start getting into this bonk state rather slowly over the next approximately 5 minutes. I was still standing all the time not becoming unconscious. I thought of having a stroke or something. Scariest moment of my life so far.
sorry for being obtuse, does orange juice help vision?
I get reactive hypoglycemia sometimes and when my blood sugar levels start dropping my vision starts blurring and I can’t focus on anything. Eating something to bring my blood sugar back resolves it. This study was about longer term deficits but I wonder if it’s the same mechanism I experience in short bursts.
I'm diabetic and experience the same thing with low blood sugar.
That's insulin resistance.
What is the thing right before I fall asleep where any voices or noises are at booming volume? Is that my brain's last chance to alert me of a predator?
Hypanagogic hallucinations. I don't know why or for what purpose they happen but that's the term.
I get these, but for me it’s not real-time noise. It’s noises and voices I heard throughout the day. It feels like they’re being replayed from a tape recorder right as I fall asleep.
Sounds similar to "auditory sleep start" aka. "exploding head syndrome". The sensation of falling which makes you twitch from your whole body is "sleep start" or "hypnic jerk" (who comes up with these names). There is also a visual version where one experiences flashes.
Probably not what you meant, but sometimes, before I fall asleep, I "see" bright flashes of light, as if there's a strobe light going off outside my window. Rarely, I also hear a loud "boom."

Apparently it's a known sleep disorder and has the terrifying name "exploding head syndrome"

https://www.sleepassociation.org/sleep-disorders/more-sleep-...

I don’t have anything to add other than that I have this too. It seems like it happens at exactly the point where I can either go to sleep or wake back up. Like suddenly all the volume rushes up and everything is at full intensity, and if I choose to sleep I guess it goes away. Super weird tbh
I think it may have to do with relative noise levels, when snoozing on the couch I get more sensitive to other people's noise sometimes, but that's also because it would be relatively quiet before.

It might be a survival mechanism, now you mention it.

Interesting, I don’t think I’ve ever experienced that (or even heard of it). Is that something you experience every night (assuming there is sound)?
Recently didn't eat for 40 days and didn't notice this. Suspect there's some issues by putting the mice on calorie restriction vs fasting. Ie "the researchers fed the mice right before the experiments" - if you're in a fasted state and do introduce food you're going to create an insulin spike - if you were also previously calorie deprived you could go hypoglycemic right after.

Going back as far as the Minnesota Starvation Experiment it appears in certain survival instances calorie restriction is worse than no calories. [1]

[1] https://en.wikipedia.org/wiki/Minnesota_Starvation_Experimen...

Ok. How did you not eat for 40 days and why?

I heard you can go without food for 30 days. My longest fast was 3 days and while I liked it, I function much better with food.

In this study that you did on yourself, did you rigorously test your visual acuity at regular intervals?
That's risky, even if it helped you lose weight. I had a former colleague who had a long fast, he ended up losing hair and he had serious joint issues for a long while after that - it caused damage, and I'm not sure he made a full recovery.
Be careful, it’s believed ~40 days without food can kill you if you don’t take supplements. People have gone for much longer while taking supplements including salt.
My speculation is that the brain activates the low-power mode when it really believes that the food is scarce. However a voluntary fasting, no matter how long, would not trigger a low-power mode since your mood is still very positive and self controlled.
Reminds me of the book "Thinking Fast and Slow", where the author describes the human brain as having two modes, the always on "fast" brain which makes lots of mistakes but doesn't consume much energy, and the more thoughtful but far more energy consuming "slow" brain. I'm not sure I agree with everything in the book, but it's some amazing food for thought and one of the highest rated books by the Hacker News community.
Interesting, I have type 1 diabetes and I experience this during low sugar episodes.
My first thought is how this dynamic interacts with early childhood education and learning.

What happens inside the brain of a child who's subject to chronic under-nourishment, and what are the long-term impacts of this?

Psilocybin high powered mode
This study might have interesting and important implications for kids in the US that suffer chronic food insecurity and do poorly in school.
Those cartoons where the stranded island goer looks at his buddy and sees a candied ham are not far from the truth.
Responding only to the title, my immediate thought was "that must be the mode I'm always in"
In cartoons when someone is really hungry they might see friend as a roasted chicken :P
Great, this article gives fat people another excuse to read a lot jk lol the study is only on mice, so who knows it’s accuracy, but makes sense
The headline is obvious (have you tried sleeping?), but the article is about a specific mechanism for vision, not the general idea.