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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

#91

Post by Nasrudith »

DoreenMichele wrote: post #13

“This gives us targets that we may eventually be able to act on with drugs to treat aging in humans.” Oy. Why do we do this nonsense? Why can't it just be research that helps us better understand how to eat healthy? /pet peeve

Two reasons. First the drug could provide better results than the most perect diet it is worth researching period. It is under fewer constraints than an organic system.

Second, because the theoretical good and the actual results don't align. We could end many STDs by only monogamously coupling for a generation but that isn't going to happen and virginity pledges haven't helped at all.

If "the right way" doesn't actually help in practice can it even be called right?

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

#92

Post by silviogutierrez »

benibela wrote: post #83
silviogutierrez wrote: post #77

Earlier quoted context omitted.

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

You did the math!

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

#93

Post by silviogutierrez »

adamgluck wrote: post #78
silviogutierrez wrote: post #77

Earlier quoted context omitted.

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…

Would be curious about the evidence you have that dietary fat is stored as (noticeable) body fat? 70% of the body is fat. Specifically, what evidence is there that dietary fat stored in a way that makes it so that it appears as noticeable body fat and causes meaningful weight gain?

This is a great read:

https://bodyrecomposition.com/fat-loss/how-we-get-fat.html/

Never mind the clickbait-ey domain. Lyle McDonald is a nutrition authority and well respected. Though on forums he’s self-admittedly volatile.

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

#94

Post by benibela »

silviogutierrez wrote: post #44
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…

To echo other replies, ketogenic and other diets diets with specific protocols (IF) do work, but primarily for behavioral reasons. That is, you’re just not that hungry. Or if you eliminate an entire meal (IF), you ”save” a ton of calories. Yes there are subtleties around actual macronutrient composition and gut flora, but the effect appears to be minimal. Find a keto person eating 5000 calories of bacon per day and I…

>That is, you’re just not that hungry. Or if you eliminate an entire meal (IF), you ”save” a ton of calories.

Or you replace high calorie food with food that does not have much calories. Like lettuce salad, which has like 17kcal. Then you would need to eat over 10kg lettuce salad to get the required 2000 kcal. That is hard to do and hard to overeat

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

#95

Post by DoreenMichele »

Nasrudith wrote: post #91
DoreenMichele wrote: post #13

“This gives us targets that we may eventually be able to act on with drugs to treat aging in humans.” Oy. Why do we do this nonsense? Why can't it just be research that helps us better understand how to eat healthy? /pet peeve

Two reasons. First the drug could provide better results than the most perect diet it is worth researching period. It is under fewer constraints than an organic system. Second, because the theoretical good and the actual results don't align. We could end many STDs by only monogamously coupling for a generation but that isn't going to happen and virginity pledges haven't helped at all. If "the right way" doesn't actua…

The problem with virginity pledges is that it's a policy of "just don't find any way whatsoever to meet your needs." Generally speaking, dietary advice doesn't boil down to "All food: bad! People who eat are all going to hell! Stop desiring food at all, you evil sinner you!"

I don't think research into how to eat well really compares one-for-one to morality policies of "sex is always bad and we will allow for one and only one right way to ever get laid while still making you feel like shit for wanting it at all."

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

#96

Post by claudiawerner »

overgard wrote: post #52
fearface wrote: post #42

Earlier quoted context omitted.

That’s a bit of BS. You don’t loose weight magically because of macronutrients. Bollocks. You loose weight, because you burn your excess fat. Without restricting your intake, there is no reason for your body to burn your fat reserves and that’s why you won’t loose weight just with low carb and same total calories. (You may loose some water, but not fat). On a ketogenic diet, your body is constantly using fat as fuel,…

I don't think you can really dismiss macro-nutrient allocation as a factor. The metabolic pathways for fats and carbohydrates are just way different. For some reason people think that this stuff works like a gas tank, where all that matters is how much fuel you pour in, but the evidence clearly shows that what kind of fuel you pour in is incredibly important. If you think about how incredibly complicated things like…

It really is like a gas tank. Just like everything else in the universe, we are regulated by the laws of physics. You can't move (live) without expending energy, and all energy put in must be transformed or stored. It's thermodynamics.

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

#97

Post by masonic »

silviogutierrez wrote: post #93
adamgluck wrote: post #78

Earlier quoted context omitted.

Would be curious about the evidence you have that dietary fat is stored as (noticeable) body fat? 70% of the body is fat. Specifically, what evidence is there that dietary fat stored in a way that makes it so that it appears as noticeable body fat and causes meaningful weight gain?

This is a great read: https://bodyrecomposition.com/fat-loss/how-we-get-fat.html/ Never mind the clickbait-ey domain. Lyle McDonald is a nutrition authority and well respected. Though on forums he’s self-admittedly volatile.

Lyle's (science) problem is that he runs with every new paper, ignoring the fact that it directly contradicts the paper he touted last year.

21 years ago (I mean this literally, I read him then) he was touting on MFW how the discovery of leptin was going to render dieting obsolete in less than a decade.

He has a lot of good content, but it's always decisive, even when some is rong.

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

#98

Post by masonic »

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.

Is that a typo? Glycogen is not a lipid. Do you mean glycerol?

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

#99

Post by silviogutierrez »

masonic wrote: post #97
silviogutierrez wrote: post #93

Earlier quoted context omitted.

This is a great read: https://bodyrecomposition.com/fat-loss/how-we-get-fat.html/ Never mind the clickbait-ey domain. Lyle McDonald is a nutrition authority and well respected. Though on forums he’s self-admittedly volatile.

Lyle's (science) problem is that he runs with every new paper, ignoring the fact that it directly contradicts the paper he touted last year. 21 years ago (I mean this literally, I read him then) he was touting on MFW how the discovery of leptin was going to render dieting obsolete in less than a decade. He has a lot of good content, but it's always decisive, even when some is rong.

Fair enough, I think nutritional science is in its nascent stages, so the whole thing is pretty vague and on shaky ground. However, some cursory empirical evidence does back most of his claims around fat gain. At least to my armchair-nutritionist satisfaction.

Anecdata, everyone's favorite - I've seen someone gain no weight eating near 100% protein, while way over their TDEE. Kid you not, 4000 kcal of lean protein and mustard.

Also morbidly, you've got alcoholics (spirits), also traditionally under weight while consuming far in excess of their TDEE in ethanol (7 kcal per gram).

So some of it can be tested in the field!

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

#100

Post by piva00 »

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.

As other commenters have pointed out, the pathway of converting dietary fat to body fat is extremely efficient compared to the ones for carbs and proteins. The body has ways to store or convert most of the macro nutrients to fat when needed, insulin spikes help with that but aren't the only mechanism to trigger fat storage.
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