Human longevity is characterised by high thyroid stimulating hormone secretion without altered energ

[paymanz]

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4473605/

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.

 

[CoolTweetPete]

Hmmm, so would this imply that supplementing thyroid is counterproductive for increasing longevity? I did not read the study but the excerpt does not provide any explanation as to why that would be the case.

 

[paymanz]

i havent read entire study but it says those people with high longevity have higher TSH and lower t4 and t3 , they havent included any explaination for this.

 

[Kasper]

Hmm... That is not what ray peat is telling us...

Would love to know what ray peat things about this

 

[haidut]

Hhhm, then what about this?
viewtopic.php?f=75&t=3704

Also, TSH a well-established stress biomarker.

 

[jaguar43]

post 98801 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4473605/

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.

This study makes the same mistake as the medical profession when diagnosing hypothyroidism or metabolic rate. TSH can be lower by adrenaline and cortisol, which could be responsible for the higher core body temperature and lower TSH. Ray Peat has said that when your stress hormones are extremely high, you may actually lower your body temperature when taking a thyroid supplement. Plus they used free t3 which ray peat and other thyroid experts have said to not be as effective as using total T3 or T3 serum. Finally, even if everything checks out and comes back normal, people can still have low t3 due to the pufa in their tissues inhibiting t3

One last thought, I think it's important to control for other factors when trying to see which biomedical characteristics promote longevity. Income level, past medical history, prenatal and postnatal environmental conditions are variables that can effect longevity rather than just subscribing to the blood test done in the study. It reminds me of those health advocates who promote eating beans and nuts because they found centenarians eating beans and nuts. Without really having a objective understanding of reality.