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The biggest losers: Metabolic damage or constrained energy?

physiqonomics.com

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

#41

Post by frankus »

SV_BubbleTime wrote: post #3
paulpauper wrote: post #2

But most contestants regained a lot of weight and metabolisms slowed relative to bodyweight and stayed slow long after regaining weight. The adaptation explains why they regained weight so fast. It's incontrovertible that the show was a failure for the majority of the contestants. this also agrees with the high failure rates of diets overall and why formerly fat people regain so fast . Biology screws you over and has…

I don’t understand how this needs anything beyond surface level complexity… you have fat people who for show reasons were tightly controlled on exercise and food intake - which works for well understood reasons - then they took that away and left the people to their lifelong established habits. Of course they regain the weight. These people didn’t magically create mass from nothing. They ate too much for their activi…

Do you have first-hand experience with being overweight and/or losing a significant amount of weight?

I think you're vastly overestimating how much of this (particularly "calories out") is under voluntary control. We're discussing an article that showed that extra active calories burned tend to lead to a compensatory reduction in resting metabolism.

And there are some very strong psychological/physiological drives that influence "calories in" (read up on the Minnesota Starvation Experiment for examples).

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

#42

Post by slothtrop »

cbsmith wrote: post #35
slothtrop wrote: post #30

The more frequent the dieting and steeper the caloric deficit, the worse metabolic adaptation gets, and the longer it takes to return to normal. As I understand it that's the result discerned from more than just one paper. Layne Norton explores this at length in his book Fat Loss Forever and yt channel. The interesting thing in this link was the impact of change in exercise regimen. We know that exercise in itself ca…

Wait. What this analysis seems to suggest is that the exercise (as long as it is a significant increase) actually encourages metabolic adaption.

Yeah I saw. But you'll see that the Biggest Loser contestants chased weight-loss on a very aggressive timeline. They have a steep deficit, and relatively high intensity exercise regimen. Which could just further exacerbate the effects of a steep deficit. At any rate, all of them had lastingly bad metabolic adaptation, even if those who exercised more had it worse.

In other studies (alluded to here as those where participants don't undergo anything so extreme), exercise is both a strong predictor of long-term weight-loss success, and can dampen metabolic adaptation (since more muscle and good cardiovascular shape boosts metabolism, usually).

I'm not sure what the lesson is yet, but I would hazard that, in the long-term, it's more important to sustain tracking energy balance (sustainability of your diet is #1). Moderate exercise can probably help, but perhaps it should also be sustainable, and in that capacity there are rapidly diminishing returns to intensity of exercise (and perhaps going hard and then quitting is a risk factor for weight regain).

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

#43

Post by SirMaster »

chiefalchemist wrote: post #26
belltaco wrote: post #10

Earlier quoted context omitted.

> These people didn’t magically create mass from nothing. They ate too much for their activity. Done. Stop doing that if you don’t want to gain weight Not true. https://www.scientificamerican.com/article/science-reveals-w... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5082693/ > discovered that certain Russian populations had large intestines that were about 57 centimeters longer on average than those of certain Pol…

> "certain Russian populations" Yes, of course. There are always outliers. But 50+% of the American population doesn't fall into this bucket, do they? Nor did they suddenly become that after they were born (i.e., obesity is a relatively new problem and not so much driven by DNA else why didn't it exist so much even just 50 yrs ago?). We keep looking for all kinds of "answers" to obesity but we already have the one th…

But what if consuming as low amount of calories as needed to be equal to or less than energy expended leaves you constantly feeling tired and with headaches and such from eating so little?

Is this not something that actually happens?

It seems like a spiral of doom. Eat less, so now I have even less energy for activity and thus now I am burning less energy, so I need to eat even less...

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

#44

Post by Angostura »

chiefalchemist wrote: post #36
csours wrote: post #23

Earlier quoted context omitted.

Hungry Brain by Guyenet is huge recommend from me, and I second the recommendation for Burn

I'll check that out. Thanks. Speaking of the brain, I've often wondered if less focus and thinking is also contributing to weight gain. The brain is responsible for ~20% of resting metabolic rate. If the brain consumes just a bit less calories per day, that's also going to add up.

The calorific difference between an active and resting brain in negligible

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

#45

Post by wexomania »

louwrentius wrote: post #17
SV_BubbleTime wrote: post #3

Earlier quoted context omitted.

I don’t understand how this needs anything beyond surface level complexity… you have fat people who for show reasons were tightly controlled on exercise and food intake - which works for well understood reasons - then they took that away and left the people to their lifelong established habits. Of course they regain the weight. These people didn’t magically create mass from nothing. They ate too much for their activi…

Sure, blame the people. Fat shame all you want. Problem solved. Done. It's so easy, just stop eating so much. As if fat people haven't heard that one a bilion times over. As if fat people havent tried time and time again. Personal responsibility! you put that stuff in your mouth, rah! rah! Personally I'm actually sick of people having no eye for the bigger picture, for many systemic reasons and larger society, and ju…

Well, it is easy to hold people accountable for what they themselves put in their mouths no?

That being said, there is some issues with the prevelance of hyperprocessed unhealthy foods.

The fact that the most unhealthy options also tend to be the cheapest and easies, really do not help.

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

#46

Post by Workaccount2 »

jay_kyburz wrote: post #16
n4te wrote: post #12

Earlier quoted context omitted.

The only thing that makes sense to me is that the body gets more efficient.

That what I imagined as I was reading, the act of breathing and pushing blood around the body just becomes easier when you are fit. (requires less energy)

Your nervous system also becomes more efficient at zapping the right muscles at the right time. The effect of this can be pretty dramatic too. Even a slightly out of sync orchestra just sounds wrong.

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

#47

Post by jklinger410 »

SV_BubbleTime wrote: post #3
paulpauper wrote: post #2

But most contestants regained a lot of weight and metabolisms slowed relative to bodyweight and stayed slow long after regaining weight. The adaptation explains why they regained weight so fast. It's incontrovertible that the show was a failure for the majority of the contestants. this also agrees with the high failure rates of diets overall and why formerly fat people regain so fast . Biology screws you over and has…

I don’t understand how this needs anything beyond surface level complexity… you have fat people who for show reasons were tightly controlled on exercise and food intake - which works for well understood reasons - then they took that away and left the people to their lifelong established habits. Of course they regain the weight. These people didn’t magically create mass from nothing. They ate too much for their activi…

> They ate too much for their activity. Done. Stop doing that if you don’t want to gain weight.

So much science out here to disprove this kind of statement, yet you still make it.

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

#48

Post by awfulneutral »

chiefalchemist wrote: post #26
belltaco wrote: post #10

Earlier quoted context omitted.

> These people didn’t magically create mass from nothing. They ate too much for their activity. Done. Stop doing that if you don’t want to gain weight Not true. https://www.scientificamerican.com/article/science-reveals-w... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5082693/ > discovered that certain Russian populations had large intestines that were about 57 centimeters longer on average than those of certain Pol…

> "certain Russian populations" Yes, of course. There are always outliers. But 50+% of the American population doesn't fall into this bucket, do they? Nor did they suddenly become that after they were born (i.e., obesity is a relatively new problem and not so much driven by DNA else why didn't it exist so much even just 50 yrs ago?). We keep looking for all kinds of "answers" to obesity but we already have the one th…

It might be that simple from a high level conceptual standpoint, but when the amount of calories you burn passively adjusts up or down as your body fights to maintain its weight, it is much more complex.

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

#49

Post by gumby »

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…

A couple of non-exclusive theories from a non-physiologist:

Your body needs to burn less to maintain / manage the fat you are or rather were carrying around.

Your body may be engaged in various processes that it turns down. It's possible, for example, that it may be engaged in various anti-cancer activities that aren't necessary as your body fat decreases (higher body fat is correlated with some cancers, though I don't believe a a direct causal link has been established...but this comment is all speculation anyway). Or the excess calories could signal your body to do other "discretionary" processes that it dispenses with in time of calorie deprivation. It's even possible that such discretionary processes could be statistically bad for you in our current environment, which might be a reason why calorie deprivation may extend lifespan, at least in modern humans.

Your gut could expend less effort to extract certain nutrients or vitamins from your food in a low calorie regime ("bah, opportunistically grabbing that extra Vitamin E is not worth the effort right now").

Just some off the top ideation, not meant to imply that these ideas are necessarily what happens but are ideas why simple thermodynamics is inadequate on its own to explain the phenomenon. The body is more than a simple calorimeter.

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

#50

Post by Angostura »

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…

In summary - the body adjusts. The increased hunger stimulated by the vigorous exercise will usually outweigh any calories burned off
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