Welcome to Debate Club! Please be aware that this is a space for respectful debate, and that your ideas will be challenged here. Please remember to critique the argument, not the author.

Scientific Research on Metabolism

2

Replies

  • NorthCascades
    NorthCascades Posts: 10,970 Member
    AnnPT77 wrote: »
    Similarly, if one expends a lot of energy on exercise, the tendency may be to rest more at other times, pulling the net back toward some mean "evolutionary" energy expenditure point. But, as with calorie counting of intake, deliberate attempts to expend more-than-average calories can still be successful . . . i.e., it's the unconscious effect of otherwise unmanaged behavior that leads energy expenditure toward some statistically common mean value/range, or intake (on a certain type of food) toward some statistically common (over-)consumption level.

    In other words, maybe we have pre-installed tendencies, but we're not powerless against them. But I'm kinda just BS-ing here. ;)

    It's obvious that we evolved a very strong set of mechanisms to avoid starvation. We like eating, calorie dense foods are delicious, and we tend to conserve energy on average which you could put uncharitably as "most people are lazy."

    But some people are more jittery than others. And some people are just drawn to risk. There's a lot of variation almost no matter what you look at. I think that includes conserving energy. We also have an evolutionary history where exploring was important, and some people are more keen on it than others.

    I'm just rambling too. I get cabin fever pretty badly, and going for a walk is almost always better than not, even when I'm exhausted.
  • AnnPT77
    AnnPT77 Posts: 31,966 Member
    AnnPT77 wrote: »
    Similarly, if one expends a lot of energy on exercise, the tendency may be to rest more at other times, pulling the net back toward some mean "evolutionary" energy expenditure point. But, as with calorie counting of intake, deliberate attempts to expend more-than-average calories can still be successful . . . i.e., it's the unconscious effect of otherwise unmanaged behavior that leads energy expenditure toward some statistically common mean value/range, or intake (on a certain type of food) toward some statistically common (over-)consumption level.

    In other words, maybe we have pre-installed tendencies, but we're not powerless against them. But I'm kinda just BS-ing here. ;)

    It's obvious that we evolved a very strong set of mechanisms to avoid starvation. We like eating, calorie dense foods are delicious, and we tend to conserve energy on average which you could put uncharitably as "most people are lazy."

    But some people are more jittery than others. And some people are just drawn to risk. There's a lot of variation almost no matter what you look at. I think that includes conserving energy. We also have an evolutionary history where exploring was important, and some people are more keen on it than others.

    I'm just rambling too. I get cabin fever pretty badly, and going for a walk is almost always better than not, even when I'm exhausted.

    Sure. All of this stuff is likely to fall somewhere on a bell curve with some pretty strong central tendencies, but some people out in the tails. It's not a line, horizontal or vertical: It's some kind of central-tendency hill.

    Y'all who are driven to do regular endurance exercise (and even still need a walk after) aren't in the same part of the statistical distribution as some of my friends, who are all about finding the least-effort grocery delivery option, getting a handicapper parking tab whenever possible so they can park by the door, and encouraging their adult kids to do their yard work. ;) Most of us, though, are somewhere in the middle. ;)
  • lynn_glenmont
    lynn_glenmont Posts: 9,961 Member
    CSARdiver wrote: »
    This would be one of the reasons I left anthropology/sociology for a field reliant upon objective evidence.

    Q: You claim that exercising more won’t increase how many calories I burn. How is that possible?

    A: The number of calories you burn per day stays pretty consistent regardless of activity level; the average adult over age 50 burns about 2,500 calories a day, depending primarily on body size. That’s your daily calorie budget. When you exercise more, your body simply lowers the number of calories it burns performing other functions, such as inflammation or hormone production. So the number of calories you burn per day — your metabolism — remains constant, whether you work out or not.

    He starts out correct – metabolism is primarily based upon mass, but your body does not lower the number of calories it burns performing other functions. Hormone production and inflammation occurs as a result of various stressors and does not hold a causational relationship to metabolism. He’s conflating basal metabolic rate with exercise.

    Q: Yet exercise is linked to weight loss. If I’m not burning calories, how am I losing weight?

    A: When people exercise, inflammation levels go down. That’s because your body is spending your energy budget on exercise and not on creating chronic inflammation. Think of inflammation as a luxury — it’s what your body will do with extra calories if you have them. And inflammation contributes to most of the diseases of aging.

    There is no objective evidence supporting this.

    Q: Extreme diets (The Biggest Loser type) can lower metabolism. If a diet can lower metabolism, why can’t we increase it?

    A: From an evolutionary standpoint, it makes sense that we can turn our metabolism down, because that preserves our life in times of famine. But it makes no sense to turn your metabolism up, because once you do that, you need more food, and you increase your risk of starvation.

    Makes sense yes, but again, no evidence to support this.

    Q: Superathletes such as swimmer Michael Phelps eat and burn tons of calories. They’ve turned up their metabolisms, right?

    A: No. If you ramp up your training to an astronomical level, you can boost your energy burn for a bit, but even elite athletes settle back into the same range. Even Phelps.

    Again – conflating and confusing basal metabolic rate with exercise.

    Q: What about diets or workouts that promise to “supercharge” metabolism?

    A: There is no such thing as a diet that can speed up your metabolism. The most effective diet is one that provides all the healthy nutrients you need while reducing your calorie intake to below your calorie budget. Think of diet and exercise as two separate tools. Exercise is great for heart health, for preventing cognitive decline, for preserving physical fitness. But if you want to lose weight, the tool for that is diet.

    The first part is correct – you cannot raise or lower your metabolism significantly other than changing your body mass.

    The second part is incorrect – you lose weight via establishing a caloric deficit, whether this be via decreasing caloric intake, increasing caloric output, or both.

    Except Muntzer does have evidence. I've listened to him on a podcast before - he's aware that what he proposes about energy expenditure goes against a lot of lab work nutrition studies humans. Yet, he has done doubly labeled water studies on hunter-gather people - it is pretty strong evidence he has their calorie expenditure / TDEE pegged. He's also used activity trackers on them to study their movement and see they are fairly active people. He's done studies on their biomechanics to see if they somehow have mastered moving in a more efficient way, but no.

    Until such time as someone can show something was done wrong in the metabolism studies with doubly labeled water, or activity tracking, the evidence he does have holds that some component of BMR is altered in the hunter-gatherers he's studied.

    I suppose I need to look into this paper itself for the parts about inflammation though.

    Did he measure their muscle mass by water displacement?
  • Cahgetsfit
    Cahgetsfit Posts: 1,912 Member
    ljmorgi wrote: »
    newmeadow wrote: »
    I heard keto changes metabolism.

    I heard Bigfoot lives in western Pennsylvania.

    @ljmorgi - You win the forums today!! LOLOLOLOLOLOL!!!
  • WonderKP
    WonderKP Posts: 146 Member
    My mom's osteoarthritis improves dramatically for her when she eats better and exercises. (when she went on vacation for a week, her pain came back)
  • rheddmobile
    rheddmobile Posts: 6,840 Member
    edited May 2019
    So... what does he say about all the athletes who gain weight when they are injured and unable to work out? How exactly is that supposed to work? Since I have been one of those people, I tend to believe that exercise burns calories and when I don’t do as much, I gain weight.

    Re: inflammation and exercise. I have lupus (an autoinflammatory disease) and have had serious flares brought on BY exercise. For the most part it seems better when I get regular exercise, up to a point, but since stress tends to cause flares, too much exercise can hurt rather than help, and it’s not always obvious on the front end how much is too much. I have also had flares come out of the blue when I was seemingly doing everything right - exercising regularly, eating appropriate calories of “healthy” foods, getting plenty of sleep.
  • ccsernica
    ccsernica Posts: 1,040 Member
    edited May 2019
    Possibly relevant brand new study just published on 16 May. When fed controlled diets of "unprocessed" and "ultra-processed" foods, the "ultra-processed" group regularly consumed around 500 kcal/day more than the "unprocessed" when both groups ate however much they wanted, and their consequent weight gain was directly correlated with energy intake. Both diets were matched in the amounts of macros and energy content presented to subjects.

    It seems the main effect of "ultra-processed" foods was to impel folks to eat more. https://www.cell.com/cell-metabolism/fulltext/S1550-4131(19)30248-7
  • Fuzzipeg
    Fuzzipeg Posts: 2,298 Member
    Thank you for the subsequent link, unfortunately it does not seem to work, at least for me.

  • ccsernica
    ccsernica Posts: 1,040 Member
    Fuzzipeg wrote: »
    Thank you for the subsequent link, unfortunately it does not seem to work, at least for me.

    Looks as if the forums don't like parentheses in URLs. You'll have to copy-paste the link into your browser's location bar.

    Or here's a tinyurl that should work: https://tinyurl.com/y26my5cp
  • magnusthenerd
    magnusthenerd Posts: 1,207 Member
    CSARdiver wrote: »
    This would be one of the reasons I left anthropology/sociology for a field reliant upon objective evidence.

    Q: You claim that exercising more won’t increase how many calories I burn. How is that possible?

    A: The number of calories you burn per day stays pretty consistent regardless of activity level; the average adult over age 50 burns about 2,500 calories a day, depending primarily on body size. That’s your daily calorie budget. When you exercise more, your body simply lowers the number of calories it burns performing other functions, such as inflammation or hormone production. So the number of calories you burn per day — your metabolism — remains constant, whether you work out or not.

    He starts out correct – metabolism is primarily based upon mass, but your body does not lower the number of calories it burns performing other functions. Hormone production and inflammation occurs as a result of various stressors and does not hold a causational relationship to metabolism. He’s conflating basal metabolic rate with exercise.

    Q: Yet exercise is linked to weight loss. If I’m not burning calories, how am I losing weight?

    A: When people exercise, inflammation levels go down. That’s because your body is spending your energy budget on exercise and not on creating chronic inflammation. Think of inflammation as a luxury — it’s what your body will do with extra calories if you have them. And inflammation contributes to most of the diseases of aging.

    There is no objective evidence supporting this.

    Q: Extreme diets (The Biggest Loser type) can lower metabolism. If a diet can lower metabolism, why can’t we increase it?

    A: From an evolutionary standpoint, it makes sense that we can turn our metabolism down, because that preserves our life in times of famine. But it makes no sense to turn your metabolism up, because once you do that, you need more food, and you increase your risk of starvation.

    Makes sense yes, but again, no evidence to support this.

    Q: Superathletes such as swimmer Michael Phelps eat and burn tons of calories. They’ve turned up their metabolisms, right?

    A: No. If you ramp up your training to an astronomical level, you can boost your energy burn for a bit, but even elite athletes settle back into the same range. Even Phelps.

    Again – conflating and confusing basal metabolic rate with exercise.

    Q: What about diets or workouts that promise to “supercharge” metabolism?

    A: There is no such thing as a diet that can speed up your metabolism. The most effective diet is one that provides all the healthy nutrients you need while reducing your calorie intake to below your calorie budget. Think of diet and exercise as two separate tools. Exercise is great for heart health, for preventing cognitive decline, for preserving physical fitness. But if you want to lose weight, the tool for that is diet.

    The first part is correct – you cannot raise or lower your metabolism significantly other than changing your body mass.

    The second part is incorrect – you lose weight via establishing a caloric deficit, whether this be via decreasing caloric intake, increasing caloric output, or both.

    Except Muntzer does have evidence. I've listened to him on a podcast before - he's aware that what he proposes about energy expenditure goes against a lot of lab work nutrition studies humans. Yet, he has done doubly labeled water studies on hunter-gather people - it is pretty strong evidence he has their calorie expenditure / TDEE pegged. He's also used activity trackers on them to study their movement and see they are fairly active people. He's done studies on their biomechanics to see if they somehow have mastered moving in a more efficient way, but no.

    Until such time as someone can show something was done wrong in the metabolism studies with doubly labeled water, or activity tracking, the evidence he does have holds that some component of BMR is altered in the hunter-gatherers he's studied.

    I suppose I need to look into this paper itself for the parts about inflammation though.

    Did he measure their muscle mass by water displacement?

    I don't recall if he said anything about composition analysis for the Hadza. I know there are others researchers that have pegged them as being rather lean, like around 12% body fat - that I recall hearing from Stephan Guyenet.

    Is the idea that they could have less lean tissue to account for a lower BMR?
  • ljmorgi
    ljmorgi Posts: 264 Member
    edited May 2019
    Cahgetsfit wrote: »
    ljmorgi wrote: »
    newmeadow wrote: »
    I heard keto changes metabolism.

    I heard Bigfoot lives in western Pennsylvania.

    @ljmorgi - You win the forums today!! LOLOLOLOLOLOL!!!

    We were there visiting family and one Sunday morning as we were driving the best thing on the radio was "Bigfoot Country Polka Party." Which included a polka version of "Ring of Fire." :#
  • heybales
    heybales Posts: 18,842 Member
    AnnPT77 wrote: »
    I'll admit to having read this casually, not closely, but I feel like the conclusion I might want to draw is that the unconscious energy-expenditure homeostasis point maybe doesn't differ as much as one might assume, between human groups with very different lifestyles, on average.

    In a sense, it seems analogous (note: not identical!) to the discussion going on now in another debate thread, about how it seems that when people are presented with ultra-processed food vs. "whole" food in iso-caloric quantities, with no other controls on behavior, the commonest behavior is to consume more calories of the ultra-processed foods than of the whole foods. The popular-press accounts tend to turn this into "processed food causes obesity", but that's not really going to be the case if calorie intake is actually managed intentionally.

    Similarly, if one expends a lot of energy on exercise, the tendency may be to rest more at other times, pulling the net back toward some mean "evolutionary" energy expenditure point. But, as with calorie counting of intake, deliberate attempts to expend more-than-average calories can still be successful . . . i.e., it's the unconscious effect of otherwise unmanaged behavior that leads energy expenditure toward some statistically common mean value/range, or intake (on a certain type of food) toward some statistically common (over-)consumption level.

    In other words, maybe we have pre-installed tendencies, but we're not powerless against them. But I'm kinda just BS-ing here. ;)

    I was just thinking about this late last night, that the hunter-gatherers probably had a decent bed time and weren't staying up till midnight running heavy baskets of laundry up and down the stairs. :D

    And how much time are we talking for the adjustments mentioned in these 2 comments, because this is easy to see in many people.

    Especially when they first start a program, or squeeze it into a busy schedule dropping other activity items.
    Less active at first with exercise, perhaps way less active, until it's figured out how to get the other stuff done.
    And I know one of the studies making this claim from years back was dealing with just extra walking being done for maybe an hour. And yeah, their daily TDEE didn't go up much if any - because their NET increase for that hour wasn't huge to begin with, and they had less steps for rest of the day, maybe even improved their sleep for longer - no huge surprise.

    If the hunter/gather's were very active moving around to find food, and then once found stay put for a bit.
    Is it the balance between many weeks - some days very active, and then some days very non-active - that puts the average where it's stating to be?

    Because I still see nothing in those podcast comments about BMR actually changing, only the TDEE which is sometimes incorrectly termed metabolism.
  • French_Peasant
    French_Peasant Posts: 1,639 Member
    heybales wrote: »
    AnnPT77 wrote: »
    I'll admit to having read this casually, not closely, but I feel like the conclusion I might want to draw is that the unconscious energy-expenditure homeostasis point maybe doesn't differ as much as one might assume, between human groups with very different lifestyles, on average.

    In a sense, it seems analogous (note: not identical!) to the discussion going on now in another debate thread, about how it seems that when people are presented with ultra-processed food vs. "whole" food in iso-caloric quantities, with no other controls on behavior, the commonest behavior is to consume more calories of the ultra-processed foods than of the whole foods. The popular-press accounts tend to turn this into "processed food causes obesity", but that's not really going to be the case if calorie intake is actually managed intentionally.

    Similarly, if one expends a lot of energy on exercise, the tendency may be to rest more at other times, pulling the net back toward some mean "evolutionary" energy expenditure point. But, as with calorie counting of intake, deliberate attempts to expend more-than-average calories can still be successful . . . i.e., it's the unconscious effect of otherwise unmanaged behavior that leads energy expenditure toward some statistically common mean value/range, or intake (on a certain type of food) toward some statistically common (over-)consumption level.

    In other words, maybe we have pre-installed tendencies, but we're not powerless against them. But I'm kinda just BS-ing here. ;)

    I was just thinking about this late last night, that the hunter-gatherers probably had a decent bed time and weren't staying up till midnight running heavy baskets of laundry up and down the stairs. :D

    And how much time are we talking for the adjustments mentioned in these 2 comments, because this is easy to see in many people.

    Especially when they first start a program, or squeeze it into a busy schedule dropping other activity items.
    Less active at first with exercise, perhaps way less active, until it's figured out how to get the other stuff done.
    And I know one of the studies making this claim from years back was dealing with just extra walking being done for maybe an hour. And yeah, their daily TDEE didn't go up much if any - because their NET increase for that hour wasn't huge to begin with, and they had less steps for rest of the day, maybe even improved their sleep for longer - no huge surprise.

    If the hunter/gather's were very active moving around to find food, and then once found stay put for a bit.
    Is it the balance between many weeks - some days very active, and then some days very non-active - that puts the average where it's stating to be?


    Because I still see nothing in those podcast comments about BMR actually changing, only the TDEE which is sometimes incorrectly termed metabolism.

    That's a good point...what are the actual activities that they are doing? Are they chasing down large game with a spear? Or are they sitting and weaving a basket to set up in a stream to trap fish? When I am hunter-gathering, I am walking slowly through the woods looking for morels, or going to a black raspberry patch and basically standing in one place for a couple hours, with a step here or there. If I were digging up cattails to store the roots over the winter that would be a large calorie burn; but if I were weaving cattails together for a shelter, it would mostly be sittin' on my butt.

    It would be interesting to see the daily activities and foods of the hunter-gatherers logged into MFP.