DragonBits
Well-Known Member
I see a lot of theories about optimum thyroid levels needing to be near the top of the typical T3 range and for TSH be near the low end of the range.
But studies indicate for longevity, higher TSH levels nearer the high end of the range and lower thyroid hormone levels are indicated. I note that in the study I am posting, they say “without altered energy metabolism”. Symptoms do matter, but I doubt very many ever determine their resting metabolic rate, and subjective feelings of lack of energy can come from many things, blood glucose and TT come to mind.
There are a lot of references if you google longevity and thyroid levels, HOWEVER I suspect nearly all of them are based on one study of offspring of nonagenarians.
Since there are many threads that say optimal thyroid levels should be near the top of the range, while these longevity studies suggest lower thyroid levels are important for a longer life, I wonder two things.
What studies were done to suggest higher thyroid levels were optimal?
What do posters think about these studies on nonagenarians?
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Human longevity is characterized by high thyroid stimulating hormone secretion without altered energy metabolism
Few studies have included subjects with the propensity to reach old age in good health, with the aim to disentangle mechanisms contributing to staying healthier for longer. The hypothalamic-pituitary-thyroid (HPT) axis maintains circulating levels of thyroid stimulating hormone (TSH) and thyroid hormone (TH) in an inverse relationship. Greater longevity has been associated with higher TSH and lower TH levels, but mechanisms underlying TSH/TH differences and longevity remain unknown. The HPT axis plays a pivotal role in growth, development and energy metabolism. We report that offspring of nonagenarians with at least one nonagenarian sibling have increased TSH secretion but similar bioactivity of TSH and similar TH levels compared to controls. Healthy offspring and spousal controls had similar resting metabolic rate and core body temperature. We propose that pleiotropic effects of the HPT axis may favour longevity without altering energy metabolism.
Human longevity is characterised by high thyroid stimulating hormone secretion without altered energy metabolism
But studies indicate for longevity, higher TSH levels nearer the high end of the range and lower thyroid hormone levels are indicated. I note that in the study I am posting, they say “without altered energy metabolism”. Symptoms do matter, but I doubt very many ever determine their resting metabolic rate, and subjective feelings of lack of energy can come from many things, blood glucose and TT come to mind.
There are a lot of references if you google longevity and thyroid levels, HOWEVER I suspect nearly all of them are based on one study of offspring of nonagenarians.
Since there are many threads that say optimal thyroid levels should be near the top of the range, while these longevity studies suggest lower thyroid levels are important for a longer life, I wonder two things.
What studies were done to suggest higher thyroid levels were optimal?
What do posters think about these studies on nonagenarians?
============================================================
Human longevity is characterized by high thyroid stimulating hormone secretion without altered energy metabolism
Few studies have included subjects with the propensity to reach old age in good health, with the aim to disentangle mechanisms contributing to staying healthier for longer. The hypothalamic-pituitary-thyroid (HPT) axis maintains circulating levels of thyroid stimulating hormone (TSH) and thyroid hormone (TH) in an inverse relationship. Greater longevity has been associated with higher TSH and lower TH levels, but mechanisms underlying TSH/TH differences and longevity remain unknown. The HPT axis plays a pivotal role in growth, development and energy metabolism. We report that offspring of nonagenarians with at least one nonagenarian sibling have increased TSH secretion but similar bioactivity of TSH and similar TH levels compared to controls. Healthy offspring and spousal controls had similar resting metabolic rate and core body temperature. We propose that pleiotropic effects of the HPT axis may favour longevity without altering energy metabolism.
Human longevity is characterised by high thyroid stimulating hormone secretion without altered energy metabolism
