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The biggest losers: Metabolic damage or constrained energy?

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Re: The biggest losers: Metabolic damage or constrained energy?

#141

Post by nradov »

paulpauper wrote: post #126
nradov wrote: post #102

Earlier quoted context omitted.

I am skeptical about reports of people who don't seem to gain much weight despite reading a lot of food. Most of those reports are merely anecdotes, or at best observational studies, and we know that most people are terrible at accurately tracking their caloric intake. More rigorous studies that involved putting subjects into locked environments and carefully measuring their intake have consistently found that the CI…

There is one individual Michael Rae who is able to do just this. He stays at 115 pounds despite eating 1,900 calories/day with a BMI of 15.6, which is insane. Most men would probably need to eat 1000-1500/day to get to that lean, as the infamous Minnesota starvation study showed, and even then many of those participants did not get that thin. Here is a profile of him, among other individuals who are part of his dieti…

There's no evidence that Michael Rae has an unusual or wasteful metabolism. 1900 kcal/day really isn't very much. With his size and input level (CI), a moderate activity level (CO) would keep him in energy balance.

Note that there is no reliable evidence that caloric restriction to the point of having an underweight BMI will actually extend human lifespans. The experiments have all been done on smaller lab animals living in safe little cages where they are protected from injuries and infectious diseases. Under nourished humans are at severe risk of sarcopenia as they age.

https://peterattiamd.com/outlive/

Re: The biggest losers: Metabolic damage or constrained energy?

#142

Post by cmrdporcupine »

belltaco wrote: post #6

> In 2016, Pontzer and colleagues published a study putting forward the constrained energy model: Energy expenditure does increase with more activity, but only to a point. Once physical activity gets really high, the body will adjust other components of the metabolism to keep your daily energy expenditure within a narrow range How do people who constantly repeat the mantra of thermodynamics in such threads explain th…

Have you ever seen a diagram of the Kreb's cycle?

This is just to say: cellular metabolism is stupidly complicated. There is so much we either do not understand yet, or have difficulty piecing together in a consistent way.

Re: The biggest losers: Metabolic damage or constrained energy?

#143

Post by sudosysgen »

paulpauper wrote: post #138
sudosysgen wrote: post #133

Earlier quoted context omitted.

That's not insane at all. At ~183cm, his BMR at 135lb would be 1600 cal/day using a standard formula, so he would only need to expend 300 calories through activity in order to breakeven, which is something many people do with just their daily routine walking around. There's nothing even slightly unusual here. The key is that very small changes in calorie intake, over a long time, have a large impact on equilibrium we…

A BMI of 16 is very rare. It's unlikely it was always that low for him. Assuming someone starts with a BMI of 22-24 and then diets to get it to 16, this would likely would req. fewer than 1900 even if the calculator says so, due to metabolic adaption and the breakdown of the calculations at extremes .

Of course it would take less than 1900 to get there. But it would take around 1900 to stay there, according to our models of basal metabolic rates. And it turns out that this person stays there at 1900, so our conclusion is that the BMR model we're using fits this data point.

It's possible that for some people at such extremes commonly available models would break down, but clearly for this person, they haven't. And while BMIs of 16 are relatively rare, so are 6 foot tall males that eat an average of 1900 calories for years.

Ultimately if you're trying to use this case to show that the models are inaccurate, that's not what this case does, it's actually remarkably close to what is predicted and if anything would be better used as evidence in their favour.

Re: The biggest losers: Metabolic damage or constrained energy?

#144

Post by treyd »

paulpauper wrote: post #131
aantix wrote: post #77

Thoughts on Adenoviruses as being a root cause of obesity? https://www.geneticlifehacks.com/weight-loss-genetics-obesit... "Interestingly, animal studies show that the gain in fat mass is not due to eating more or moving less… Animals ate the same amount of chow, but those infected with adenovirus 36 increased fat tissue by 60-80%." https://pubmed.ncbi.nlm.nih.gov/17135605/ "A 2004 twin study showed that the Ad-36 an…

So why is obesity getting worse recently when Adenoviruses has always existed?

With something as essential as metabolism it's likely to be a combination of factors. Some might not cause a change when present in isolation but cause a large change when present simultaneously.

Re: The biggest losers: Metabolic damage or constrained energy?

#145

Post by paulpauper »

nradov wrote: post #141
paulpauper wrote: post #126

Earlier quoted context omitted.

There is one individual Michael Rae who is able to do just this. He stays at 115 pounds despite eating 1,900 calories/day with a BMI of 15.6, which is insane. Most men would probably need to eat 1000-1500/day to get to that lean, as the infamous Minnesota starvation study showed, and even then many of those participants did not get that thin. Here is a profile of him, among other individuals who are part of his dieti…

There's no evidence that Michael Rae has an unusual or wasteful metabolism. 1900 kcal/day really isn't very much. With his size and input level (CI), a moderate activity level (CO) would keep him in energy balance. Note that there is no reliable evidence that caloric restriction to the point of having an underweight BMI will actually extend human lifespans. The experiments have all been done on smaller lab animals li…

The Minnesota starvation study showed that the formulas fail when extreme weight loss occurs. So if someone starts with a BMI of 22-24 or so and then tries to get to 15.6, will burn way fewer calories than predicted by the calculators/formulas. 1900 is not much but a BMI of 15.6 is pretty low. He did not start that low, so I wonder how much he was eating before he embarked on this experiment. As for extending lifespan, agree, that the data is iffy on that.

Re: The biggest losers: Metabolic damage or constrained energy?

#146

Post by soulbadguy »

ninkendo wrote: post #132
soulbadguy wrote: post #128

Earlier quoted context omitted.

Well the point i am trying to make is that your explanation on why it work for you is probably wrong, and even more the advice you generate from your theory can be dangerous and counter productive. > Right, that’s called propositional logic. It’s perfectly valid to make “CICO works” predicated upon whether you follow it correctly. Well no. And that really the core of the issue. I see that you didn't answer to the exa…

Your understanding of CICO (or at least the point I am making about it) is wrong in your “B” paragraph. My argument boils down to the following: For every individual, at any given time, there is a metabolic rate M for which, if their calorie intake was larger than that, they’d gain weight, and if their calorie intake was smaller, they’d lose weight. Crucially, M changes over time. But going CICO properly means using…

> Your understanding of CICO (or at least the point I am making about it) is wrong in your “B” paragraph.

Just to clarify B is not cico, it's the inference that you seems to make from CICO.

> For every individual, at any given time, there is a metabolic rate M for which, if their calorie intake was larger than that, they’d gain weight, and if their calorie intake was smaller, they’d lose weight. Crucially, M changes over time

This is "not" the definition of CICO, and again does not follow from CICO. CICO is fundamentally a thermodynamic statement about the observed state of a system. You are making predictive statement about a possible future state of the system.

Again, if you want to believe that statement that's fine. The point i am making is just it's does not follow from cico, no have i seen anything empirically that validate that statement.

> Since M is determined by empirical observations of your weight loss/gain in response to the calories you have consumed, you will by definition lose weight if you consume less than M calories.

sure this derived from your "definition" of CICO... but your definition is not thermodynamically derived...

> This is the argument that CICO must work by definition

the premise (the definition of the argument) is flawed.

> It’s a logical contradiction for it not to work.

Not really, CICO not working (as in this case) can be just the result of sound logic based on bad premises.

Re: The biggest losers: Metabolic damage or constrained energy?

#147

Post by aantix »

paulpauper wrote: post #131
aantix wrote: post #77

Thoughts on Adenoviruses as being a root cause of obesity? https://www.geneticlifehacks.com/weight-loss-genetics-obesit... "Interestingly, animal studies show that the gain in fat mass is not due to eating more or moving less… Animals ate the same amount of chow, but those infected with adenovirus 36 increased fat tissue by 60-80%." https://pubmed.ncbi.nlm.nih.gov/17135605/ "A 2004 twin study showed that the Ad-36 an…

So why is obesity getting worse recently when Adenoviruses has always existed?

A hypothesis is outlined in the article I linked to above. https://www.geneticlifehacks.com/weight-loss-genetics-obesit...

"If the adenovirus infections are playing a role in our obesity epidemic, this would need to be due to infections rising, starting around the early 1980s, when obesity levels started steadily increasing.

I mentioned above that obesity has doubled since 1980 — and that adenovirus seropositivity had doubled by the mid-2000s (Swedish study).

Here’s the CDC graph again – looking at the green lines (dashed green is women and solid green is men)

One piece of the puzzle as to why this could be happening is the increase in kids in daycare, which has been rising since the 80s. A study looking at overweight kids (9-12) found that Ad-36 increased the risk of obesity by 3-fold and that kids who were in daycare before age 24 months were also at an almost 3-fold risk of obesity.[ref]

Another interesting puzzle piece is that Ad36 was first isolated in 1978 in Germany.[ref] (This may not mean that it first existed in 1978, though, just that it wasn’t well-known before then. Other adenoviruses were identified in the 1930s.)"

Re: The biggest losers: Metabolic damage or constrained energy?

#148

Post by magicalhippo »

ninkendo wrote: post #88
throwup238 wrote: post #83

Earlier quoted context omitted.

> This approach is generally referred to the calorie-in/calorie-out (CICO) model. While true to an extent, this perspective is too simplistic, given one key fact: leptin is primarily produced in adipose tissue [1]. This fact means body fat is actually an endocrine system organ. This part I think needs more explanation. The reason calories-in/calories-out model is too simplistic (I would call it almost useless if not…

CICO doesn’t work across individuals for reason you outline (just because I lose weight with a certain level of calories, doesn’t mean you will, etc.) But for a single individual, working to establish your base metabolic rate by counting every calorie and weighing yourself regularly, you can always find a way to be successful with the CICO model. If you establish a baseline that your metabolic rate is (say) 2000 calo…

I found CICO very helpful in losing weight (from 120kg to 90kg).

It was a relatively easy metric to track, and using it alone meant that I could still eat all the things I wanted, though I needed to balance what I wanted to eat with portion size.

CICO also meant I started out slow, making small cuts. So it wasn't bad in the beginning. Over time I had to find ways to adapt so I wouldn't go feeling hungry (mostly increase protein and fiber ratio significantly), but I never needed big changes.

On the flip side CICO also meant that if I messed up one day it wasn't so bad. It just moved the goal post one day or two further away. So it prevented me from feeling like there was no point and giving up, instead getting back into it the next day.

By following CICO I had a very linear weight loss, which didn't feel like a restriction or such. I estimated my CO and aimed for roughly 0.5kg per week and that's almost exactly what I managed.

Not being "prevented" from certain foods due to diet X was a big factor in making this bearable.

Re: The biggest losers: Metabolic damage or constrained energy?

#149

Post by chiefalchemist »

cmrdporcupine wrote: post #140
DiscourseFan wrote: post #31

Earlier quoted context omitted.

I've managed to keep a good amount of weight off for years, but only with vigilance, because even a couple weeks of unrestrained eating can be disastrous. I'm not at my lowest ever weight, that was during COVID, when I got hit with a nice Δ-variant, and lost my appetite for a month before force-feeding myself back to normal. That was the my first experience with truly unhealthy weight loss, and made me realize that w…

Encountering someone with a serious anorexic eating disorder, or watching a loved one with cancer -- who was formerly slim and healthy -- whither away their insufficient fat reserves while under treatment... can put things in an entirely different perspective. My mild obesity doesn't seem so bad now. I'd rather have a little too much and be fine with it... than be psychologically tortured by it, or not have enough in…

In those two case, sure extra weight seems like a positive. But have back problems? Or leg issues? And that extra weight will make you even less mobile. Can't move? That'll get you bed sores and perhaps eventually an infection.

The body didn't evolve to carry so much extra weight. You're on the wrong side of history.

Re: The biggest losers: Metabolic damage or constrained energy?

#150

Post by chiefalchemist »

Angostura wrote: post #115
voisin wrote: post #61

Earlier quoted context omitted.

Interesting! Source?

Quite a few, but https://www.scientificamerican.com/article/thinking-hard-cal... https://www.sciencefocus.com/the-human-body/does-concentrate...

From the second link

"There have been some experiments to show that abstract problem solving does raise the brain’s metabolic requirements, and the higher your IQ, the more extra energy you can expend in this way. But it’s unlikely to amount to more than five calories an hour, either way. So you can’t Sudoku yourself slim"

5 kcals x 15 hrs = 75 kcals.

Actually, this is significant in the sense that if you over kcal by 100 kcals per day that'll add up. 75 is 75% of 100.

It looks small but in the context of weight, 75 kcals per day is enough to make a difference.

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