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how many calories do you eat when you are sedentary? Watch

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    (Original post by Angry cucumber)
    Somatotypes are bogus

    The majority of people of the same gender differ very little in their BMR per kg.

    The reason some people are like sticks vs not, is appetite

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    Somatotypes are indeed a bunch of turd in most respects, but in terms of BMR we shouldn't overlook the role of thyroid hormones in regulating the metabolic rate. Even if two women weighing 50kg have their thyroid function checked and come back within the normal range, the difference between a free T3 level of 3.5 (the low end of the range) and one of 6.5 (the high end of the range) can mean a difference of up to 1000 calories between the BMRs of both.

    Same reason why it seems like OP seems to burn more calories than myself as a BMR even though I'm 50+lbs heavier :lol: Though, yeah, must be said that a lot of people under or overeat consistently or else they wouldn't have weight problems.
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    (Original post by WoodyMKC)
    Somatotypes are indeed a bunch of turd in most respects, but in terms of BMR we shouldn't overlook the role of thyroid hormones in regulating the metabolic rate. Even if two women weighing 50kg have their thyroid function checked and come back within the normal range, the difference between a free T3 level of 3.5 (the low end of the range) and one of 6.5 (the high end of the range) can mean a difference of up to 1000 calories between the BMRs of both.

    Same reason why it seems like OP seems to burn more calories than myself as a BMR even though I'm 50+lbs heavier :lol: Though, yeah, must be said that a lot of people under or overeat consistently or else they wouldn't have weight problems.
    Thyroid hormones fluctuate daily. weekly, monthly etc. If you're always in the normal range which the overwhelming majority of people are, thyroid hormones mean sweet FA for anyone. Sure BMR varies person to person... by about 100 cals. There's studies I've posted before finding no significant differences between people of similar height, weight etc. If you're 6'5 and hyperthyroid vs 4'10'' and hypothyroid then fair enough there's going to be a hell of a difference but as the majoirty of people are young, the reason they're fat is eating too much, the reason they're too thin is because the appetite is that of a shrew.

    I've never seen any evidence showing much in the way of different T4/ 3 levels having any effect on metabolism; if you have seen a few studies, would be interested to read of course

    If we were discussing middle age women, whole different topic. Hypothyroid common and menapause effect to boot. Males to a lesser extent.
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    (Original post by Angry cucumber)
    Thyroid hormones fluctuate daily. weekly, monthly etc. If you're always in the normal range which the overwhelming majority of people are, thyroid hormones mean sweet FA for anyone. Sure BMR varies person to person... by about 100 cals. There's studies I've posted before finding no significant differences between people of similar height, weight etc. If you're 6'5 and hyperthyroid vs 4'10'' and hypothyroid then fair enough there's going to be a hell of a difference but as the majoirty of people are young, the reason they're fat is eating too much, the reason they're too thin is because the appetite is that of a shrew.

    I've never seen any evidence showing much in the way of different T4/ 3 levels having any effect on metabolism; if you have seen a few studies, would be interested to read of course

    If we were discussing middle age women, whole different topic. Hypothyroid common and menapause effect to boot. Males to a lesser extent.
    They do indeed fluctuate, but in normal people not to the extent that they're ranging from low-normal to high-normal regularly. A range of 3 might seem small, but pmol is a large measurement and a difference of 3pmol/l would be huge and would mean a difference of 500 calories at the very least. In fact, eating under maintainance for significant periods (i.e. weeks) is the only normal occurance that lowers thyroid hormone production significantly and subsequently BMR, whereas conversely overfeeding stimulates them.

    Endocrinology basics, mate. T4 is just a supplier of T3 really, however you could say that T3 is THE regulator of the metabolism and is literally the only reason that thyroid hormones exist - more T3 = higher BMR via increased heat production from increased oxygen consumption and ATP hydrolysis. There are also numerous studies to suggest that T3 plays a role in fat mobilisation, though there are other studies that suggest no correlation.

    Been working my way through The Hormone Handbook by Thierry Hertoghe for a third time as it happens, I have no idea why as it's not the most exciting book ever, but I've taken a serious interest in hormones over the past year. It's ****ing expensive to get hold of but it's a brilliant read. My aunt-in-law is letting me borrow it, she did a lot of studying from it in the last 5-odd years and has recently become a fully certified endo so I'm always digging her brains as well :lol:
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    (Original post by WoodyMKC)
    They do indeed fluctuate, but in normal people not to the extent that they're ranging from low-normal to high-normal regularly. A range of 3 might seem small, but pmol is a large measurement and a difference of 3pmol/l would be huge and would mean a difference of 500 calories at the very least. In fact, eating under maintainance for significant periods (i.e. weeks) is the only normal occurance that lowers thyroid hormone production significantly and subsequently BMR, whereas conversely overfeeding stimulates them.
    Sick Euthyroid is actually the mechanism that lowers thyroid hormone concs, it occurs in any harsh caloric deficit for a prolongued period the glossy mag STARTVATION SYNDROME!!!!1111 is that. And also if you have flu etc, because pyrexia and inflammation requires energy, your thyroid hormones reduce to prevent you losing too much weight

    Endocrinology basics, mate. T4 is just a supplier of T3 really, however you could say that T3 is THE regulator of the metabolism and is literally the only reason that thyroid hormones exist - more T3 = higher BMR via increased heat production from increased oxygen consumption and ATP hydrolysis. There are also numerous studies to suggest that T3 plays a role in fat mobilisation, though there are other studies that suggest no correlation.
    Yes I get that, but I'm not convinced at all that having normal range thyroid hormones is a reason why someone is fat nor am I convinced it's changing a BMR by 500 calories being in the normal range. If that were true we'd be blood testing everyone and dosing everyone with thyroxine -> Obesity epidemic solved.

    It's pretty widly accepted that T3/4 /thyroid hormones cause fat mobilisation directly or at least indirecty. It's what we were taught

    Been working my way through The Hormone Handbook by Thierry Hertoghe for a third time as it happens, I have no idea why as it's not the most exciting book ever, but I've taken a serious interest in hormones over the past year. It's ****ing expensive to get hold of but it's a brilliant read. My aunt-in-law is letting me borrow it, she did a lot of studying from it in the last 5-odd years and has recently become a fully certified endo so I'm always digging her brains as well :lol:
    Nice, dat contacts
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    (Original post by Angry cucumber)
    Sick Euthyroid is actually the mechanism that lowers thyroid hormone concs, it occurs in any harsh caloric deficit for a prolongued period the glossy mag STARTVATION SYNDROME!!!!1111 is that. And also if you have flu etc, because pyrexia and inflammation requires energy, your thyroid hormones reduce to prevent you losing too much weight



    Yes I get that, but I'm not convinced at all that having normal range thyroid hormones is a reason why someone is fat nor am I convinced it's changing a BMR by 500 calories being in the normal range. If that were true we'd be blood testing everyone and dosing everyone with thyroxine -> Obesity epidemic solved.

    It's pretty widly accepted that T3/4 /thyroid hormones cause fat mobilisation directly or at least indirecty. It's what we were taught



    Nice, dat contacts
    Pretty much both saying the same thing there then :lol: Thyroid hormones only fluctuate wildly under extreme physiological conditions.

    Oh absolutely, thyroid hormones are never totally to blame for someone being fat, it's their choice to eat over their maintenance and not exercise, I'd never go to say that everyone who is overweight is hypothyroid, far from in fact. Hence why we're not just handing out T4 willy nilly. However, the point that people make about people of the same weight having the same BMR is incorrect. Thyroid hormones exist purely to control the metabolism and BMR - differing thyroid hormones = differing metabolic rates. If we have someone who is diagnosed hypothyroid vs someone of the same weight who is hyperthyroid, obviously their weight problems are going to be totally opposite to each other, and that's with a difference of 3pmol. Most likely a difference of 1000+ calories in BMR.
 
 
 
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