Homeostasis weight

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  • jjpptt2
    jjpptt2 Posts: 5,650 Member
    CSARdiver wrote: »
    Wheelhouse15 wrote: »
    jjpptt2 wrote: »
    Wheelhouse15 wrote: »
    jjpptt2 wrote: »
    I listened to a podcast once by, IIRC, Stephan Guyenet. He made the point that there is a certain body fat percentage that your body tries to maintain. If you get too far on either side of that, your body will be less or more likely to store fat, in attempt to get back to what is essentially a healthy BF level.

    That's certainly not the same thing as set point theory, at least not the way it's typically talked about in dieting circles, but it is related. Ultimately, habits and behaviors dictate if you lose/gain/maintain.

    Pretty much the case. The body has certain, limited, mechanisms that it can employ to reduce caloric expenditures and this shows up as adaptive thermogenesis, but the main strategy is to increase intake through the hunger response and behaviours driven by that. The way it's often portrayed you would think the body has some amazing abilities to just shutdown metabolism anytime it feels like it, which it can't if it wants to remain viable.

    Does it go the other way, too... If one is "too lean", the body is more apt to respond with increased hunger signals. If one is overly fat, does the body respond with fewer hunger signals?

    Assuming one has and is in tune with fairly normal hunger signals...

    When the body weight rises there seems to be some issues with various hormones that affect hunger signals such as leptin and insulin insensitivities. So this can cause issues when a person tries to diet. The body does reduce hunger signals but it doesn't mean people stop eating. We know that there are behavioural components to overeating because people are capable of eating past normal satiety, and it really doesn't take a lot of overeating, especially with highly calorific foods, to gain a considerable amount of weight over a period of time.

    If the body is too lean, yes, hunger is increased and that's easily seen in professions that diet excessively like bodybuilders, models, and actors as well as in anorexics.

    The biggest issue is really that people's eating behaviours are not strictly dictated by biological needs but by social and environmental cues as well as habits formed over time.

    Hormones are free cycling, so simply being overweight makes it extremely difficult if not impossible to maintain hormonal balance as the respective glands cannot produce the needed hormone in sufficient quantities. A similar issue occurs in underweight subjects, but the glands overproduce hormones and poses challenges to the signal/response chain.

    There is a clear distinction between appetite signals (desire for food) and hunger signals (actual physical need for food) - these have to be addressed and mitigation implemented for any successful weight management plan.

    Appetite signals are quick and immediate - cravings for specific foods - chocolate, coffee, sweet, salty, etc. and strongly driven by hormones. Hunger signals are much slower and non-specific. General stomach discomfort (rumblings) followed by weakness, irritability, shaking, fatigue, malaise.

    As for adaptive thermogenesis this works in the same manner as a fire. Provide more fuel in a short period of time results in a hotter flame, but quick burning. Sustained fuel over a longer time results in lower temp, but longer burn. BMR/REE operates in a similar manner in the short term. The immediate adaptive nature takes place over 24-72 hours and trending towards mean. You see this in dramatic changes such as 10,000 kcal/day challenges resulting in a dramatic increase in BMR.

    That's a great response, thank you. While I knew most of that already, the way you framed up the concepts is really helpful. Its like seeing a picture in B&W vs color - still the same picture, but wow, a huge difference.
  • aniracace
    aniracace Posts: 39 Member
    A true myth is an oxymoron
  • Wheelhouse15
    Wheelhouse15 Posts: 5,575 Member
    CSARdiver wrote: »
    Wheelhouse15 wrote: »
    jjpptt2 wrote: »
    Wheelhouse15 wrote: »
    jjpptt2 wrote: »
    I listened to a podcast once by, IIRC, Stephan Guyenet. He made the point that there is a certain body fat percentage that your body tries to maintain. If you get too far on either side of that, your body will be less or more likely to store fat, in attempt to get back to what is essentially a healthy BF level.

    That's certainly not the same thing as set point theory, at least not the way it's typically talked about in dieting circles, but it is related. Ultimately, habits and behaviors dictate if you lose/gain/maintain.

    Pretty much the case. The body has certain, limited, mechanisms that it can employ to reduce caloric expenditures and this shows up as adaptive thermogenesis, but the main strategy is to increase intake through the hunger response and behaviours driven by that. The way it's often portrayed you would think the body has some amazing abilities to just shutdown metabolism anytime it feels like it, which it can't if it wants to remain viable.

    Does it go the other way, too... If one is "too lean", the body is more apt to respond with increased hunger signals. If one is overly fat, does the body respond with fewer hunger signals?

    Assuming one has and is in tune with fairly normal hunger signals...

    When the body weight rises there seems to be some issues with various hormones that affect hunger signals such as leptin and insulin insensitivities. So this can cause issues when a person tries to diet. The body does reduce hunger signals but it doesn't mean people stop eating. We know that there are behavioural components to overeating because people are capable of eating past normal satiety, and it really doesn't take a lot of overeating, especially with highly calorific foods, to gain a considerable amount of weight over a period of time.

    If the body is too lean, yes, hunger is increased and that's easily seen in professions that diet excessively like bodybuilders, models, and actors as well as in anorexics.

    The biggest issue is really that people's eating behaviours are not strictly dictated by biological needs but by social and environmental cues as well as habits formed over time.

    Hormones are free cycling, so simply being overweight makes it extremely difficult if not impossible to maintain hormonal balance as the respective glands cannot produce the needed hormone in sufficient quantities. A similar issue occurs in underweight subjects, but the glands overproduce hormones and poses challenges to the signal/response chain.

    There is a clear distinction between appetite signals (desire for food) and hunger signals (actual physical need for food) - these have to be addressed and mitigation implemented for any successful weight management plan.

    Appetite signals are quick and immediate - cravings for specific foods - chocolate, coffee, sweet, salty, etc. and strongly driven by hormones. Hunger signals are much slower and non-specific. General stomach discomfort (rumblings) followed by weakness, irritability, shaking, fatigue, malaise.

    As for adaptive thermogenesis this works in the same manner as a fire. Provide more fuel in a short period of time results in a hotter flame, but quick burning. Sustained fuel over a longer time results in lower temp, but longer burn. BMR/REE operates in a similar manner in the short term. The immediate adaptive nature takes place over 24-72 hours and trending towards mean. You see this in dramatic changes such as 10,000 kcal/day challenges resulting in a dramatic increase in BMR.

    Thanks, this is very good background information and is even more detailed than I usually like to go and I can be really pedantic lol.

    The only thing I would point out for interest is that we do see some longer term effects with adaptive thermogenesis that seem to be more persistent, often seen years later, but not particularly profound. I'll have to go back to the long vs short term effects again but the one that stick in my mind is T3/T4 levels in the blood seem to be slightly depressed. The initial research indicated a model where BMR was supressed over the longer term around 15-20% IIRC, but there were mathematical errors and it's really somewhere around 8% lower than would be predicted.

    I think the thing that sticks in my mind the most, however, about adaptive thermogenesis and the long term effects is that I don't think there have been any studies to determine if the people who dieted to lose weight had those issues before, and thus these were already contributing factors to their previous weight issues. All of the studies I've seen on it show post hoc effects of those who have already lost weight without a corresponding baseline. So I really don't know if the long term effects are induced through diet or were already there.

  • AnvilHead
    AnvilHead Posts: 18,343 Member
    edited January 2018
    There are a lot of physiological and behavioral factors which influence weight regulation (gain/loss/maintenance). None of them have anything to do with CICO itself.

    Every person who tries to go about disproving CICO inevitably conflates it with other factors. It seems that often, it's because they don't really understand what CICO actually is in the first place - or they choose to ignore it because that's the only way they can make their argument relevant.
  • Wheelhouse15
    Wheelhouse15 Posts: 5,575 Member
    CSARdiver wrote: »
    kimny72 wrote: »
    I think some of this has already been touched on, but TBH some of the more recent posts have gone over my head LOL. But anyway, the main reason I always roll my eyes when someone says "set point!" is because it's only ever meant to explain why you can't lose weight. If your body truly had a weight it was programmed to defend, wouldn't it also fight to keep you from getting bigger? So if you think you are screwed because your body won't let you go below 180 lbs, and that must be your set point, why did it let you go 40 lbs above 180?

    Having said that, the discussion going on in here about behavior, and hunger cues, and hormones, add in societal pressure and cultural differences, can all conspire to make it difficult to maintain behaviors that will get you to a goal weight. And I think it's fair to say with a simple understanding of energy balance that there is most likely a weight range where you will be most comfortable based on all these factors, where you can stay close to effortlessly. But this isn't necessarily your body "deciding" you should be a specific weight and fighting you. It means that based on your height, musculature, bone structure, and activity level you need to eat at a calorie level that is a challenge to you due to your habits, preferences, state of mind, previous dieting habits, general health, etc. If you can bust through all that and eat the correct calories, you will lose weight.

    My thoughts exactly.

    This is where I find the concept of set point brought up - as an excuse. ...and I cannot hide my distaste for excuse makers and use facts and data to dispel and destroy these myths that set people up for failure.

    Even if this nonsense was true, then so what? Either adapt for a solution or despair and fail.

    There is always a way of overcoming, we see that here and in the Weight Loss Registry as well.

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