"Higher Metabolism, Temperature And Pulse And Lower TSH Associated With Higher Mortality"

[Giraffe]

Are we to believe that every one of these studies, which all have a consistent conclusion, are so fundamentally flawed that we should ignore them. I am not so sure that many of your criticisms would support such a conclusion

I didn't ask you to ignore those studies. I asked you to read them, and decide for yourself if the assumptions made there make sense, and if the data support the claims that were made.

Studies do not "all have a consistent conclusion". If you read studies, you will find references to studies that came to different conclusions.

For example, you asked “has any of the studies controlled the participants for adrenaline levels or thyroid status (including T3)?”

People compensate for low thyroid function with high amounts of cortisol and adrenaline. Studies, that check for temperature or heart rate or oxygen consumption, but not for stress hormones or elevated FFA or whether the oxygen is efficiently used or wasted, do get some sort of results, and they call it metabolism, but stress metabolism is not what Peat means when he talks about the benefits of a higher metabolic rate.

I will let you present your concerns with incorrect covariate assumptions and covariate selections since you are making the charge. I am sure the scientists, peer reviewers, and publications would all like to know as well.

That's big of you!

For example, a common covariate is the cholesterol level. The current dogma says that high cholesterol is a risk factor for atherosclerosis, heart disease and stroke. Hypothyroidism causes hypercholerestolemia, and both can be corrected with supplementing thyroid hormones. If you introduce cholesterol as a covariate in a multi-hazard model which is supposed to describe the relation between heart disease and thyroid status, you distort the results.

 

[Queequeg]

I didn't ask you to ignore those studies. I asked you to read them, and decide for yourself if the assumptions made there make sense, and if the data support the claims that were made.

Come on, the thread is filled with one hit after another on why the thyroid papers are incorrect and the last post is filled with generic attacks on the metabolic studies. Anyone reading those posts without thinking would easily think that they should ignore the studies.

Studies do not "all have a consistent conclusion". If you read studies, you will find references to studies that came to different conclusions.

You're changing my words. I said "every one of these studies," as in the posted studies above. I obviously wasn't referring to every study out there.

That's big of you!
For example, a common covariate is the cholesterol level. The current dogma says that high cholesterol is a risk factor for atherosclerosis, heart disease and stroke. Hypothyroidism causes hypercholerestolemia, and both can be corrected with supplementing thyroid hormones. If you introduce cholesterol as a covariate in a multi-hazard model which is supposed to describe the relation between heart disease and thyroid status, you distort the results.

Big of me, not so sure, but you implied that one or more of the studies made a mistake in its multivariate analysis and I only asked you to state what mistakes specifically were made. Though you didn't do that, I do appreciate the explanation of what is a confounding variable.

Unfortunately your response stops there, and again you don't address my main point. If you don't want to discuss it, that's fine. However, just in case, you want to or someone else wants to comment, I'll briefly sum it up again.

As we all know, Ray believes that higher metabolism and temperatures lead to better health and increased longevity. To support his position, Ray cites two papers and points to the effect of mitochondrial uncoupling. Unfortunately the paper says that mitochondrial uncoupling takes place mostly in smaller animals like rodents. Nowhere does it say that enough uncoupling takes place in humans to make increased metabolism a good thing. More details are given further back in the thread.

I think this is important because many of us are working hard to raise our metabolisms. If higher metabolisms do in fact lead to a shorter life like most other scientists believe, we should probably stop doing that.

 

[Queequeg]

Maybe the metabolic rate is not so important after all. Mathematician/biologist Lloyd Demetrius suggested that the most important factor involved in duration of life is not metabolic rate or oxidative stress, but metabolic stability.
"Evolutionary biologist Lloyd Demetrius believes that life-span potential is related to an organism’s ability to maintain stable levels of critical cellular metabolites, not to its metabolic rate. The traditional theory that longevity and rate of aging are determined by metabolic rate and the rate of production of free radicals has had broad appeal as an explanation for why some animals live longer than others. But numerous exceptions to this rule (including the FIRKO mouse) have undermined the idea over time."
The Aging Enigma

Interesting paper. I looked further into this theory and found a couple other papers just on metabolic stability.

A New Theory on Longevity
What Determines Longevity: Metabolic Rate or Stability? - S. Jay Olshansky - Discovery Medicine

My understanding is that rodents being more opportunistic and having less control of their environment have a much less stable metabolism. Humans on the other hand have a higher metabolic stability so this theory doesn't do much for us since we cant really raise our stability much more. I think he is trying to explain some of the anomalies in metabolism vs longevity tests across species.

"The bad news (or perhaps good news, depending on your fondness for food) is that our already high metabolic stability means caloric restriction will not lead to dramatic life extension, as it does for mice." "A New Theory on Longevity

As I wrote above, others believe that mitochondrial uncoupling is the reason why some small animals don't follow the typical metabolism/longevity relationship.

 

[Giraffe]

Come on, the thread is filled with one hit after another on why the thyroid papers are incorrect and the last post is filled with generic attacks on the metabolic studies. Anyone reading those posts without thinking would easily think that they should ignore the studies.

You're changing my words. I said "every one of these studies," as in the posted studies above. I obviously wasn't referring to every study out there.

I genuinely believed that you were talking about published research in general and not only about a few cherry-picked studies linked in a blog-article which appears to aim at casting doubts about Peat's ideas.

Anyway, if you think that I refuse all those studies linked there as "rigged or flawed," then you misread my posts. If you read those studies you will find that some of them address some of the points I made in my last post. No "generic attacks on the metabolic studies" at all. By the way, you can read a well-conducted study and come to different conclusions than the authors!

Have a look at the Baltimore study:

In a prospective study in men with around 40 years of follow-up, a higher basal metabolic rate was independently associated with a higher mortality compared to average metabolic rates. Low metabolic rates were not significantly associated with higher mortality (Figure: Mortality plotted according to quartiles of metabolic rate). http://www.ncbi.nlm.nih.gov/pubmed/18693224

From that study:

We hypothesized that pathology and accelerated aging increase the BMR because extra energy is required to counteract wide fluctuations in the homeostatic equilibrium (6).

RMR declines with age. The paper which's theory was tested suggested that an increased RMR in geriatric patients might be a sign that something it out of whack.

 

[Agent207]

Some people around here tends to think the higher the metabolism the better, because hypothyroidism is bad.

Its like the pufa thing and almost every single thing; good/bad.

Imo, out of hypothyroidism you want a normal metabolic rate, with tsh <2 and in range thyroid levels. You don't want the metabolism the higher the better because that's as bad as the hipo and in both cases sure you will age faster.

 

[Queequeg]

Have a look at the Baltimore study.

you mean this one? High basal metabolic rate is a risk factor for mortality: the Baltimore Longitudinal Study of Aging. - PubMed - NCBI
or this one "IDEAL" aging is associated with lower resting metabolic rate: the Baltimore Longitudinal Study of Aging. - PubMed - NCBI

I have read them and agree with their conclusions. Do you have some human studies that say the opposite?
Any thoughts on the Speakman paper?

Some people around here tends to think the higher the metabolism the better, because hypothyroidism is bad.
Its like the pufa thing and almost every single thing; good/bad.
Imo, out of hypothyroidism you want a normal metabolic rate, with tsh <2 and in range thyroid levels. You don't want the metabolism the higher the better because that's as bad as the hipo and in both cases sure you will age faster.

I completely agree. I am not sure why this is so controversial as the science is pretty clear.

 

[Queequeg]

[ moderator edit: posts moved from The Benefits Of Decreased Thyroid Function ]

When I brought this subject up before, I felt as if I had walked through the looking glass or looked behind the curtain. There is an element of religious belief about this and if you dare question it you get attacked like what happened above.

I have seen little evidence that increasing thyroid hormone to get your TSH as low as possible, as RP recommends, is actually healthy for you. But I have seen a lot of evidence that it is fairly unhealthy for you. The same could be said for raising your temperatures and metabolism. The evidence in humans is that lower metabolisms and heart rates are associated with longer lifespans.

As far as the goal being an efficient metabolism, raising your temperatures and eating more is actually the sign of a less efficient metabolism.

Here is a thread were its been brought up before:
"Higher Metabolism, Temperature And Pulse And Lower TSH Associated With Higher Mortality"

 

[Queequeg]

Why would a low tsh signal something bad... it just means your body is not making it's own thyroid? Does whatever study you are referring to say inflammation happens when you get below a certain tsh level? Did it read other signs of inflammation... like estrogen.level, prolactin, vitamjn d, etc? Its pretty obvious around here just looking at one factor doesn't mean everything...

Yeah if you get your tsh low af and have low vit D and no calcium... your gonna have a bad time..

"Higher Metabolism, Temperature And Pulse And Lower TSH Associated With Higher Mortality"

 

[mayweatherking]

"Higher Metabolism, Temperature And Pulse And Lower TSH Associated With Higher Mortality"

This has got to be a joke right? Two of the last studies said old people had a higher tsh then adults. No Duh... they are over 100, magically they are going to have better performing bodies? Wtf? Lol. One study says old centurians had lower serum zinc as well as higher tsh. Ummm yes... they are over 100... so we are not supposed to have zinc now.l either if.people over 100 have low zinc? This is not evidence low tsh is bad..... some people smoke and live to 100, does it make it ok?

 

[Queequeg]

This has got to be a joke right? Two of the last studies said old people had a higher tsh then adults. No Duh... they are over 100, magically they are going to have better performing bodies? Wtf? Lol. One study says old centurians had lower serum zinc as well as higher tsh. Ummm yes... they are over 100... so we are not supposed to have zinc now.l either if.people over 100 have low zinc? This is not evidence low tsh is bad..... some people smoke and live to 100, does it make it ok?

LOL is right...you are just cherry picking what studies you happen to think have a flaw in them and then try to dismiss the other 8 studies that say the same thing. I have a novel idea; how about presenting a study that proves your theory is correct, that higher metabolism, higher temperatures and/or lower TSH are beneficial to humans. I haven't seen any.

 

[mayweatherking]

LOL is right...you are just cherry picking what studies you happen to think have a flaw in them and then try to dismiss the other 8 studies that say the same thing. I have a novel idea; how about presenting a study that proves your theory is correct, that higher metabolism, higher temperatures and/or lower TSH are beneficial to humans. I haven't seen any.

The other studies looked like they compared and contrasted tsh over long periods of time to see who lived the longest and those with higher tsh lived longer. I mean, it doesn't look like they compared anything else at all... you think tsh alone is the only important thing? We have no idea how these people are living or eating or anything, there could be many other factors at play... ray peat would never look at tsh alone... its far from the only thing contributing to problems...

 

[Queequeg]

The other studies looked like they compared and contrasted tsh over long periods of time to see who lived the longest and those with higher tsh lived longer. I mean, it doesn't look like they compared anything else at all... you think tsh alone is the only important thing? We have no idea how these people are living or eating or anything, there could be many other factors at play... ray peat would never look at tsh alone... its far from the only thing contributing to problems...

That's how science/statistics work. It can be safely assumed that if the sample is large enough then any variation in the health metrics of the sample group matches that of the population at large so you can then make conclusions about the effect of changes in different independent variables. Confounding variables can be statistically controlled for through multi-variate analysis to determine the isolated effect of each independent variable in question. Many different conclusions can therefore be drawn from the same longitudinal study. As an example the Framingham Heart Study has had over a thousand research papers written on it.

 

[mayweatherking]

That's how science/statistics work. It can be safely assumed that if the sample is large enough then any variation in the health metrics of the sample group matches that of the population at large so you can then make conclusions about the effect of changes in different independent variables. Confounding variables can be statistically controlled for through multi-variate analysis to determine the isolated effect of each independent variable in question. Many different conclusions can therefore be drawn from the same longitudinal study. As an example the Framingham Heart Study has had over a thousand research papers written on it.

Okay.... well sounds like you are convinced. ... im personally not considering rays principles far exceed outside of tsh alone.. enjoy that sugar free life. :P

 

[jaguar43]

"Higher Metabolism, Temperature And Pulse And Lower TSH Associated With Higher Mortality"

If Ray Peat argues that using TSH as a indication of thyroid function is incorrect and an unreliable way to measure thyroid function. Then why would you post a page in which most studies conclude that a higher TSH is associated with lower mortality as evidence that a low metabolism is beneficial ?

 

[Queequeg]

If Ray Peat argues that using TSH as a indication of thyroid function is incorrect and an unreliable way to measure thyroid function. Then why would you post a page in which most studies conclude that a higher TSH is associated with lower mortality as evidence that a low metabolism is beneficial ?

That's not my understanding. Ray does say that basal temperatures and symptoms are better to measure thyroid activity for an individual but he does not say that TSH tests are incorrect or unreliable, especially as used for research. If he thought TSH was unreliable he wouldn't recommend a TSH of below 0.4. Anyway since the vast majority of research on thyroid uses TSH, we don't really have a choice.

I posted the page in response to someone who asked why would a low TSH indicate something bad. The various studies in that article show that low TSH, high metabolism and high temperatures are all associated with shortened longevity.

 

[jaguar43]

That's not my understanding. Ray does say that basal temperatures and symptoms are better to measure thyroid activity for an individual but he does not say that TSH tests are incorrect or unreliable, especially as used for research. If he thought TSH was unreliable he wouldn't recommend a TSH of below 0.4. Anyway since the vast majority of research on thyroid uses TSH, we don't really have a choice.

I posted the page in response to someone who asked why would a low TSH indicate something bad. The various studies in that article show that low TSH, high metabolism and high temperatures are all associated with shortened longevity.

For diagnosing hypothyroidism, he does not recommend it. He says so in the interview with Josh Rubin.

JR: So you’ve been touching upon TSH. What are your thoughts on TSH? Because I know that a lot of the different values out there are very different and they are always changing a little so if you could touch upon you know if you even would recommend focusing on TSH that much and if you do, what would you say the value should be?

RP: Yeah, I don't recommend it as a way to diagnose hypothyroidism

The Thyroid (East West Healing Blog Talk Radio, 2011)

TSH can be used to measure thyroid functioning while on thyroid medication or to see it from a different context other than measuring the metabolic rate. But if one uses it from the medical establishment perspective, it pretty useless in the diagnosis and to say that someone who has a lower metabolic rate lives longer based on TSH levels is incorrect. TSH doesn't correctly reflect the metabolic rate. You cannot argue that those studies prove your argument of the benefits of decrease thyroid function since TSH can't accurately diagnose hypothyroidism. Apparently it can't even accurately diagnosis hyperthyroidism.

Increasingly, TSH (the pituitary thyroid stimulating hormone) has been treated as if it meant something independently; however, it can be brought down into the normal range, or lower, by substances other than the thyroid hormones.

Aging, infection, trauma, prolonged cortisol excess, somatostatin, dopamine or L-dopa, adrenaline (sometimes; Mannisto, et al., 1979), amphetamine, caffeine and fever can lower TSH, apart from the effect of feedback by the thyroid hormones, creating a situation in which TSH can appear normal or low, at the same time that there is a real hypothyroidism.

Although food intake and metabolic rate vary from day to day, an approximate calorie count for several days can often make it clear that a diagnosis of hyperthyroidism is mistaken. If a person is eating only about 1800 calories per day, and has a steady and normal body weight, any “hyperthyroidism” is strictly metaphysical, or as they say, “clinical.”

Preventing and treating cancer with progesterone.

Interestingly Ray Peat in his article specifically stated that aging can decrease TSH, making it appear that they have a low TSH. It's important to point out that the studies from that page you posted are done on elderly people. So I think your whole premise is incorrect.

 

[mayweatherking]

Exactly.... there are sooo many factors not accounted for in those studies... taking tsh ONLY out of ray peats work is an absolute insult and to only look at that one thing in studies makes no sense... even if a lower tsh was bad for the average American diet... rays lower tsh makes sense in HIS diet... slamming down 2500mg of calcium, 4700 mg of potassium, 100grams of protein, 200-300grams+ of carbs, eating ever hr or two, etc etc, the high metabolism will not push cortisol up, the body completely runs on food alone, stress hormones are specically meant to be as low as possible...

These studies, you have no idea there.eating habits or anything at all... for all we know there low tsh is pushing them to have high stress hormones. .. which is honestly why they probably dont live as long...

Is there even a reason for why the studies say a low tsh will cause a smaller span of life?

 

[Queequeg]

For diagnosing hypothyroidism, he does not recommend it. He says so in the interview with Josh Rubin.
TSH can be used to measure thyroid functioning while on thyroid medication or to see it from a different context other than measuring the metabolic rate. But if one uses it from the medical establishment perspective, it pretty useless in the diagnosis and to say that someone who has a lower metabolic rate lives longer based on TSH levels is incorrect. TSH doesn't correctly reflect the metabolic rate. You cannot argue that those studies prove your argument of the benefits of decrease thyroid function since TSH can't accurately diagnose hypothyroidism. Apparently it can't even accurately diagnosis hyperthyroidism.

Increasingly, TSH (the pituitary thyroid stimulating hormone) has been treated as if it meant something independently; however, it can be brought down into the normal range, or lower, by substances other than the thyroid hormones.

Aging, infection, trauma, prolonged cortisol excess, somatostatin, dopamine or L-dopa, adrenaline (sometimes; Mannisto, et al., 1979), amphetamine, caffeine and fever can lower TSH, apart from the effect of feedback by the thyroid hormones, creating a situation in which TSH can appear normal or low, at the same time that there is a real hypothyroidism.

Although food intake and metabolic rate vary from day to day, an approximate calorie count for several days can often make it clear that a diagnosis of hyperthyroidism is mistaken. If a person is eating only about 1800 calories per day, and has a steady and normal body weight, any “hyperthyroidism” is strictly metaphysical, or as they say, “clinical.”

Preventing and treating cancer with progesterone.

Interestingly Ray Peat in his article specifically stated that aging can decrease TSH, making it appear that they have a low TSH. It's important to point out that the studies from that page you posted are done on elderly people. So I think your whole premise is incorrect.

Exactly.... there are sooo many factors not accounted for in those studies... taking tsh ONLY out of ray peats work is an absolute insult and to only look at that one thing in studies makes no sense... even if a lower tsh was bad for the average American diet... rays lower tsh makes sense in HIS diet... slamming down 2500mg of calcium, 4700 mg of potassium, 100grams of protein, 200-300grams+ of carbs, eating ever hr or two, etc etc, the high metabolism will not push cortisol up, the body completely runs on food alone, stress hormones are specically meant to be as low as possible...
These studies, you have no idea there.eating habits or anything at all... for all we know there low tsh is pushing them to have high stress hormones. .. which is honestly why they probably dont live as long...
Is there even a reason for why the studies say a low tsh will cause a smaller span of life?

As you can see below, it's not true that all the studies focused on TSH or only on old people. These studies looked at variety of independent variables and their effects on longevity, including basal metabolic rate, heart rate, temperature and TSH. All showed the opposite of what Ray is claiming.

As I tried to explain to @mayweatherking, science works best by looking at one independent variable at a time to see its effects on a selected dependent variable. If you had to control for every variable in a human study like he seems to suggest, you could never have any human trials. Luckily you don't have to as confounding variables are dealt with either statistically or by proper sample selection. And again, just because TSH can be manipulated by other means or isn't always the best diagnostic of thyroid does not mean it can't be used as a proper measure of thyroid function. It is still strongly correlated with thyroid function and so is properly used for scientific research on thryoid.

Ray makes a very unorthodox claim that higher metabolisms, higher heart rates, higher temperatures, and/or higher thyroid function are healthful yet no one can seem to provide any scientific evidence for this. If we are just going to take his word for it and reject any study that states otherwise, than we are no longer discussing science but are debating religious dogma.

Higher metabolism, temperature and pulse and lower TSH associated with higher mortality

• In a prospective study in men with around 40 years of follow-up, a higher basal metabolic rate was independently associated with a higher mortality compared to average metabolic rates. Low metabolic rates were not significantly associated with higher mortality (Figure: Mortality plotted according to quartiles of metabolic rate). High basal metabolic rate is a risk factor for mortality: the Baltimore Longitudinal Study of Aging. - PubMed - NCBI

• In the same study, a higher temperature was associated with increased mortality compared to people with a lower temperature over 25-years of follow-up (Figure: X-axis: Survival time (yrs), Y-axis: Cumulative survival; plotted for higher or lower body temperature). Biomarkers of caloric restriction may predict longevity in humans. - PubMed - NCBI
  
• Mice that have been genetically engineered to have a 0.3 to 0.5°C lower body temperature have an increased life span compared to normal mice despite having the same caloric intake. Transgenic mice with a reduced core body temperature have an increased life span. - PubMed - NCBI
• In a prospective study in male and females with average 11 years of follow-up, a higher 24 hour energy expenditure was associated with higher mortality from diseases. Higher energy expenditure in humans predicts natural mortality. - PubMed - NCBI
• In a 16-year follow-up study, an elevated resting heart rate in men without cardiovascular disease is associated with an increased all-cause mortality, even when adjusting for cardiovascular risk factors. A lower resting heart rate wasnt associated with higher mortality (Figure: All-cause mortality according to groups of resting heart rate). Elevated resting heart rate, physical fitness and all-cause mortality: a 16-year follow-up in the Copenhagen Male Study. - PubMed - NCBI
  
• In a prospective study of 52.674 participants with median 8.8 years follow-up, a TSH under 0.45 mIU/L is associated with increased all-cause mortality, cardiovascular mortality and atrial fibrillation compared to a TSH between 0.45 to 4.49 mIU/L Subclinical Hyperthyroidism and the Risk of Coronary Heart Disease and Mortality
• In two cross-sectional studies of long lived individuals, longevity was associated with lower fT3 and fT4 and higher TSH values Familial longevity is associated with decreased thyroid function. - PubMed - NCBI A cross-section analysis of FT3 age-related changes in a group of old and oldest-old subjects, including centenarians' relatives, shows that a down... - PubMed - NCBI
• A genetic polymorphism that leads to higher TSH is associated with longevity http://www.ncbi.nlm.nih.gov/pubmed/19837933
• In a prospective study of 85-year olds with 4-years of follow-up, a TSH over 4.8mIU/L is associated with significantly lower mortality compared to subjects with average or suppressed TSH levels. Low serum T4 combined with high TSH was also associated with lower mortality. http://www.ncbi.nlm.nih.gov/pubmed/16642639
• Centenarians had a higher TSH compared to younger controls. No differences in fT4 values were found. http://www.ncbi.nlm.nih.gov/pubmed/19158193
• Italians "oldest-old (90-107 years) had a higher TSH, lower fT3/fT4 ratio and lower serum zinc and selenium than adult or elderly control subjects. http://www.ncbi.nlm.nih.gov/pubmed/10852460

 

[mayweatherking]

As you can see below, it's not true that all the studies focused on TSH or only on old people. These studies looked at variety of independent variables and their effects on longevity, including basal metabolic rate, heart rate, temperature and TSH. All showed the opposite of what Ray is claiming.

As I tried to explain to @mayweatherking, science works best by looking at one independent variable at a time to see its effects on a selected dependent variable. If you had to control for every variable in a human study like he seems to suggest, you could never have any human trials. Luckily you don't have to as confounding variables are dealt with either statistically or by proper sample selection. And again, just because TSH can be manipulated by other means or isn't always the best diagnostic of thyroid does not mean it can't be used as a proper measure of thyroid function. It is still strongly correlated with thyroid function and so is properly used for scientific research on thryoid.

Ray makes a very unorthodox claim that higher metabolisms, higher heart rates, higher temperatures, and/or higher thyroid function are healthful yet no one can seem to provide any scientific evidence for this. If we are just going to take his word for it and reject any study that states otherwise, than we are no longer discussing science but are debating religious dogma.

Higher metabolism, temperature and pulse and lower TSH associated with higher mortality

• In a prospective study in men with around 40 years of follow-up, a higher basal metabolic rate was independently associated with a higher mortality compared to average metabolic rates. Low metabolic rates were not significantly associated with higher mortality (Figure: Mortality plotted according to quartiles of metabolic rate). High basal metabolic rate is a risk factor for mortality: the Baltimore Longitudinal Study of Aging. - PubMed - NCBI

• In the same study, a higher temperature was associated with increased mortality compared to people with a lower temperature over 25-years of follow-up (Figure: X-axis: Survival time (yrs), Y-axis: Cumulative survival; plotted for higher or lower body temperature). Biomarkers of caloric restriction may predict longevity in humans. - PubMed - NCBI
  
• Mice that have been genetically engineered to have a 0.3 to 0.5°C lower body temperature have an increased life span compared to normal mice despite having the same caloric intake. Transgenic mice with a reduced core body temperature have an increased life span. - PubMed - NCBI
• In a prospective study in male and females with average 11 years of follow-up, a higher 24 hour energy expenditure was associated with higher mortality from diseases. Higher energy expenditure in humans predicts natural mortality. - PubMed - NCBI
• In a 16-year follow-up study, an elevated resting heart rate in men without cardiovascular disease is associated with an increased all-cause mortality, even when adjusting for cardiovascular risk factors. A lower resting heart rate wasnt associated with higher mortality (Figure: All-cause mortality according to groups of resting heart rate). Elevated resting heart rate, physical fitness and all-cause mortality: a 16-year follow-up in the Copenhagen Male Study. - PubMed - NCBI
  
• In a prospective study of 52.674 participants with median 8.8 years follow-up, a TSH under 0.45 mIU/L is associated with increased all-cause mortality, cardiovascular mortality and atrial fibrillation compared to a TSH between 0.45 to 4.49 mIU/L Subclinical Hyperthyroidism and the Risk of Coronary Heart Disease and Mortality
• In two cross-sectional studies of long lived individuals, longevity was associated with lower fT3 and fT4 and higher TSH values Familial longevity is associated with decreased thyroid function. - PubMed - NCBI A cross-section analysis of FT3 age-related changes in a group of old and oldest-old subjects, including centenarians' relatives, shows that a down... - PubMed - NCBI
• A genetic polymorphism that leads to higher TSH is associated with longevity Genetic predisposition to elevated serum thyrotropin is associated with exceptional longevity. - PubMed - NCBI
• In a prospective study of 85-year olds with 4-years of follow-up, a TSH over 4.8mIU/L is associated with significantly lower mortality compared to subjects with average or suppressed TSH levels. Low serum T4 combined with high TSH was also associated with lower mortality. Mortality in a complete 4-year follow up of 85-year-old residents of Leiden, classified by serum level of thyrotropin and thyroxine. - PubMed - NCBI
• Centenarians had a higher TSH compared to younger controls. No differences in fT4 values were found. Extreme longevity is associated with increased serum thyrotropin. - PubMed - NCBI
• Italians "oldest-old (90-107 years) had a higher TSH, lower fT3/fT4 ratio and lower serum zinc and selenium than adult or elderly control subjects. Blood micronutrient and thyroid hormone concentrations in the oldest-old. - PubMed - NCBI

okay... but what if the people didn't eat enough calcium? do you think that would effect their longevity at all? unfortunately, we don't have the answer to that question.

 

[DaveFoster]

Exactly.... there are sooo many factors not accounted for in those studies... taking tsh ONLY out of ray peats work is an absolute insult and to only look at that one thing in studies makes no sense... even if a lower tsh was bad for the average American diet... rays lower tsh makes sense in HIS diet... slamming down 2500mg of calcium, 4700 mg of potassium, 100grams of protein, 200-300grams+ of carbs, eating ever hr or two, etc etc, the high metabolism will not push cortisol up, the body completely runs on food alone, stress hormones are specically meant to be as low as possible...

These studies, you have no idea there.eating habits or anything at all... for all we know there low tsh is pushing them to have high stress hormones. .. which is honestly why they probably dont live as long...

Is there even a reason for why the studies say a low tsh will cause a smaller span of life?

Smoking tobacco lowers TSH.