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New report on the cellular effects of a calorie-restricted diet in rats

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Re: New report on the cellular effects of a calorie-restricted diet in rats

#81

Post by PeterisP »

pen2l wrote: post #62
adamgluck wrote: post #58

Earlier quoted context omitted.

This actually isn’t entirely true. You’re operating under the “energy in-energy out” theory of weight loss, but human regulation of body fat is more complicated than that. Specifically, we store energy in adipose tissue in the form of body fat after a meal (think of it like storing data on disk) and then when we are low on energy we burn that fat (load that data “in-memory”). However, a lot regulates when we burn fat…

> You’re operating under the “energy in-energy out” theory of weight loss, but human regulation of body fat is more complicated than that. I hear the "energy in-energy out" being dismissed like this often, and while I do agree with you that our bodies are more complex than that, I want to say that in practice this adage more or less just works, indeed to the degree that it's valuable to have in common knowledge to in…

The thing is that "energy in-energy out" works if you make some changes while keeping everything else constant.... and we're really, really bad at keeping everything else constant.

Add extra activity, and the natural effect will be an increased appetite that'll nudge you to eat more calories - and it's not a given the effect of that extra activity will be a calorie deficit, the increase in appetite can easily be more than what you spent in those exercises.

If you try to reduce caloric intake, that's a very different beast than actually reducing caloric intake - if you try to reduce caloric intake by skipping carbs at lunch, it can result in reduced activity (so less calories out) and a strong nudge to "cheat" at other meals or snacks; and again it's plausible to get to a situation where the unintended compensation is larger (and opposite) than the behavior modification that you made.

That is the problem with the "energy in-energy out" model - one does not simply change the 'energy in' or 'energy out' part and expect that other things will stay constant either magically or through sheer willpower.

Re: New report on the cellular effects of a calorie-restricted diet in rats

#82

Post by krzat »

adamgluck wrote: post #36

The only reason a study like this works is because it takes place in a controlled environment where they can actually starve the rats (or sometimes make genetic changes that reduce the rats hunger.) Study after study and clinical experience shows that low calorie diets are really hard for humans “in the wild” to maintain in practice. People who are on them constantly complain of hunger (in the mid-20th century these…

Not hard using IF, you could cut 30% and still feel full at least once a day.

Re: New report on the cellular effects of a calorie-restricted diet in rats

#83

Post by benibela »

silviogutierrez wrote: post #77
adamgluck wrote: post #58

Earlier quoted context omitted.

This actually isn’t entirely true. You’re operating under the “energy in-energy out” theory of weight loss, but human regulation of body fat is more complicated than that. Specifically, we store energy in adipose tissue in the form of body fat after a meal (think of it like storing data on disk) and then when we are low on energy we burn that fat (load that data “in-memory”). However, a lot regulates when we burn fat…

So, yes and no. That's why I said "primarily." It's wayyyyy more complicated than calories-in vs calories-out. But 90% of it does come down to that. More importantly though, you need to define what "calories-in" means. I like to think of a silly extreme. If I drink a gallon of gasoline, I've technically consumed what, a billion calories? But I won't gain a single gram.[1] Why? There's no metabolic pathway to convert…

>I like to think of a silly extreme. If I drink a gallon of gasoline, I've technically consumed what, a billion calories? But I won't gain a single gram.[1] Why? There's no metabolic pathway to convert gasoline to ATP.

26579 kcal

Re: New report on the cellular effects of a calorie-restricted diet in rats

#84

Post by JMTQp8lwXL »

zackmorris wrote: post #48

I wish that it was possible to do a caloric restriction study on people who work out. I spent most of my 20s eating roughly twice as much as average and hitting the gym 3-4 times per week and I never felt better, especially after 20 rep squat sessions that naturally raise hormones like testosterone and HGH. I occasionally cut calories to lose weight or train my metabolism to be "ready" for emergency situations (which…

Since most people aren't going to commit to bodybuilding 3-4x a week for life, I'd imagine a calorie-restricted diet is the superior option for them. Eating a lot and working a lot, might be superior to eating little and working out little, but eating a lot and working out little has to have the worst outcomes.

Re: New report on the cellular effects of a calorie-restricted diet in rats

#85

Post by tsimionescu »

visarga wrote: post #74
tsimionescu wrote: post #43

Earlier quoted context omitted.

While you are possibly correct that those may be somewhat realistic historic diets, why do you think they would be favorable to a longer, healthier life? Evolution doesn't generally optimize for longevity, it only optimizes for reproduction. The lifespan of most animals in the wild is much shorter than what can be achieved with a carefully controlled diet.

Humans have a long childhood and even the availability of the grandparents can increase the chances of survival of the child. So we adapted to live longer.

Is there any proof that more primitive humans (ones who ate a more natural diet, I mean) lived longer or had other benefits (e.g. seem younger at older ages)?

Re: New report on the cellular effects of a calorie-restricted diet in rats

#86

Post by ruminasean »

ravenstine wrote: post #35
ruminasean wrote: post #17

I've done strict calorie tracking for restriction, keto as well as IF. The best I've ever felt was keto, the easiest for me to adhere to was calorie tracking. It's marginally harder if you eat out a lot, but if you cook for yourself and can throw everything on a food scale for a week or so until you get an idea of what's servings of your most commonly-eaten foods looks like, tracking calories made losing weight for m…

That's interesting, because while I think keto is great in a lot of ways, I've never felt my best on it. It just doesn't give me the energy I need to be effective in the gym. What I've discovered doing 72 hour fasts is that what I eat when I refeed matters a lot less than when I'm eating throughout the day. Keto made a big difference in my initial weight loss journey, but I find it to be somewhat miserable for mainte…

I've found this to be the case too. Been on mostly keto for roughly 2-3 years, done several short and long fasts, and I test my blood daily. There were days after fasting and then eating something that really should've knocked me out of ketosis where it barely made a dent. The whole thing is really very interesting.

Re: New report on the cellular effects of a calorie-restricted diet in rats

#87

Post by superpermutat0r »

adamgluck wrote: post #65
superpermutat0r wrote: post #59

Earlier quoted context omitted.

How can the body, given 5000 kcal in fat not store any of that fat in the adipose tissue?

Your body responds to the intake of carbohydrates by creating insulin which regulates the storage of carbohydrates as “body fat” (see: glycogen). Overall, your body is 70% fat (cell membranes, for example). In other words, dietary fat != body fat and there is no reason that your body would store it as such (in adipose tissue), it actually, mechanistically, as far as I know, cannot.

But glycogen is not fat in the adipose tissue. Glycogen goes into muscles and is a ready fuel, fuel ready for fast metabolic burn. The metabolism to turn carbohydrates and protein into fat is insanely inefficient compared to just storing fat as fat.

And fat is the first thing to get stored when there's an insulin spike, not to mention the carbs+fat combination is the thing that creates insulin resistance exactly because of the fat messing everything up.

So I'm thinking, and please correct me if I'm wrong, that you are just repeating some keto "truth" that does not really make sense. Because when I googled that, the only sources were pretty much some keto promoting pages.

Re: New report on the cellular effects of a calorie-restricted diet in rats

#88

Post by ip26 »

Many of the observed effects at least distantly remind me of the known effects of exercise.

I wonder if there's an intersection, e.g. without adjusting your eating habits, exercise results in an effectively calorie-restricted diet?

If there is no intersection, I wonder which is more valuable than the other? Not much exercise is going to be happening on a starvation diet.

Re: New report on the cellular effects of a calorie-restricted diet in rats

#89

Post by Gibbon1 »

ip26 wrote: post #88

Many of the observed effects at least distantly remind me of the known effects of exercise. I wonder if there's an intersection, e.g. without adjusting your eating habits, exercise results in an effectively calorie-restricted diet? If there is no intersection, I wonder which is more valuable than the other? Not much exercise is going to be happening on a starvation diet.

I think during physical work your muscles consume glucose. Potentially large amounts. The liver gives up it's stores of glycogen. Afterwords the liver will efficiently take up glucose to replenish it's stores of glycogen. I think that dynamic is a lot better than the insulin mediated glucose to fat conversion dynamic you get with sedentary people.

Re: New report on the cellular effects of a calorie-restricted diet in rats

#90

Post by Nasrudith »

visarga wrote: post #74
tsimionescu wrote: post #43

Earlier quoted context omitted.

While you are possibly correct that those may be somewhat realistic historic diets, why do you think they would be favorable to a longer, healthier life? Evolution doesn't generally optimize for longevity, it only optimizes for reproduction. The lifespan of most animals in the wild is much shorter than what can be achieved with a carefully controlled diet.

Humans have a long childhood and even the availability of the grandparents can increase the chances of survival of the child. So we adapted to live longer.

Reminds me of cephalopods and their outright suicidal reproduction in contrast. It involved a specific gland and when removed they would starve themselves to death anyway.

Granted it is a very different niche in the ecosystem but it hints that it is a matter of self-perpetuation where longer lifespan in this case is a side effect.

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