The Association of Reduced Thyroid Function With Longevity

The thyroid gland carries out a number of important functions, responding to changing conditions by varying its production of thyroid hormones that alter the behavior of metabolism elsewhere in the body. The behavior of the thyroid changes with age, but in a sufficiently subtle and varying manner to make its role in aging a challenging thing to study. Nonetheless, there is at this point enough data to conclude that some forms of reduced thyroid function tend to associate with increased longevity in a number of species.

This also ties in with other lines of research. Calorie restriction, for example, reduces thyroid hormone levels in the course of extending life and improving health. A predisposition to low thyroid hormone levels appear to be inherited in long-lived families. And so forth.

Here is a short and very readable open access review paper that looks at thyroid function in the context of aging and longevity:

The thyroid gland and the process of aging; what is new?

The endocrine system and particular endocrine organs, including the thyroid, undergo important functional changes during aging. The prevalence of thyroid disorders increases with age and numerous morphological and physiological changes of the thyroid gland during the process of aging are well-known.

Intriguingly, decreased thyroid function, as well as thyrotropin (TSH) levels - progressively shifting to higher values with age - may contribute to the increased lifespan. [The] most striking findings concerning potential contribution of TSH and thyroid hormones to lifespan regulation, were obtained in the studies performed on centenarians (and almost centenarians). In 2009, Atzmon et al. published the results of studies on thyroid disease-free population of Ashkenazi Jews, characterized by exceptional longevity (centenarians). They have observed higher serum TSH level in these subjects as compared to the control group. [Moreover], the authors have observed an inverse correlation between FT4 and TSH levels in centenarians and [controls], and finally, they have distinctly concluded that increased serum TSH is associated with extreme longevity

The above-mentioned inverse correlation between FT4 and TSH in centenarians may suggest a potential role of decreased thyroid function in lifespan regulation, leading to remarkable longevity. Such a hypothesis seems to have been confirmed by the findings obtained in the Leiden Longevity Study, demonstrating the associations between low thyroid activity and exceptional familial longevity.

It should be stressed that reduced thyroid function with low levels of T4 is associated with extended longevity also in animals. For example, a very severe thyroid hypofunction with reduced core body temperature, as observed in Ames dwarf (df/df) and Snell mice [is] considered to substantially contribute to remarkable longevity in these rodents. [The] findings in animals are consistent with the results obtained in humans and may confirm a relevant role of thyroid hypofunction in lifespan extension.

Comments

From a personal perspective very troubling info considering I take a thyroid supplement for a condition I'm supposed to have but have none of the symptoms of.

Posted by: Louis Burke at November 30th, 2012 5:31 AM

So, let me see. High TSH is associated with longevity. High TSH is also associated with low thyroid hormones, muscle pain, fatigue, foggy thinking, overweight, fluid retention,impotence, depression even to the point of suicide. So, this study would have us believe high TSH extends lifespan--with these symptoms?! Is life worth living feeling and being like that?

This is another instance of science looking myopically at one factor: how long one lives. NOT how well one lives. The more valid endeavor is to find out how to live longer--healthier and happier! This study has nothing to do with that.

Posted by: David Dressler, BA, RMT at December 2nd, 2012 8:58 PM

I would contend that the research is in no way myopic. Now we know that high TSH extends live. So now we can try to find ways of eliminating the symptoms if the increased life span warrants the time, money and/or effort.

Posted by: Lance Chambers at December 3rd, 2012 7:49 PM

In case anyone is reading this in February, months after Lance Chambers wrote: "So now we can try to find ways of eliminating the symptoms [of low thyroid I mentioned] if the increased life span warrants the time, money and/or effort." The point is, this myopic research would imply one has to get sick to live longer. Chambers says, but that gives the time to find a solution. A solution to what? To being made sicker by deliberately lowering TSH without concern for the fact high TSH is the body's way of compensating for not enough thyroid hormone (a disease of the thyroid of some kind). The high TSH is like a fire alarm telling you the house is burning down. You don't stop the fire alarm or turn the volume down. If you do, you burn to death. High TSH is a symptom, not the condition. Smart people and smart doctors treat causes not symptoms.

Posted by: David Dressler, BA, RMT at February 4th, 2013 10:17 PM

High TSH is not necessarily associated with low thyroid hormone levels. In subclinical hypothyroidism the thyroid hormone levels are normal or only slightly lower than average with a slightly elevated TSH (range of 3 - 6).

It is also rather ludicrous to assume that increased levels of TSH CAUSE longevity. They are merely associated with it in this homogeneous population. Realistically, having lower free T4 is probably best in old age since you don't want metabolic processes ageing an already aged body so this is good, but if it was a natural mechanism instead of simply an age-related thyroid function decline, the TSH should be lower since it is secreted by the pituitary gland to signal to the thyroid how much T4 (and to a lesser extent T3) to create and/or send out into the body for conversion to free T3.

In order for this study to be meaningful, I think it needs to be replicated in other centenarian groups like Okinawans.

Posted by: ashley at June 6th, 2013 5:16 PM

To Ashley (if she is reading this half a year later): High TSH does mean low thyroid. You wrote that high TSH does not mean low normal thyroid level. Yes, it does. The reason you think it doesn't is because the range of so-called "normal" in thyroid hormone testing is too broad. This means thousands of people with hypothyroid symptoms are declared "normal" by their doctors. This is because these doctors are treating these patients' lab results and not the patients.

You also wrote: "Realistically, having lower free T4 is probably best in old age since you don't want metabolic processes ageing an already aged body so this is good." You must be kidding! Having low T4 means there will not be enough T3 quite likely. T3 is the active form of thyroid hormone. You can have lots of T4 and inadequate amounts of T3 for a variety of reasons having to do with poor conversion of T4 to T3, and also what is called reverse T3, a lack of iodine and/or tyrosine. Since the thyroid gland is the metabolic "thermostat" in the body, runs all the organs, why would anyone want a low thermostat? Why would anyone want slow digestion, poor assimilation, accumulation in the bowel and kidney,slowed heart rate, fluid retention, weight gain, sluggish energy, poor concentration, thinning hair,impotence, depression, early dementia, and the list goes on? No; adequate thyroid function, which means higher numbers than currently are considered "normal", is a foundation of health and well being. Sure, if you slow the thyroid down you slow combustion of food-borne nutrients, cutting down oxidation via free radical activity, and might live longer. But the point is, how healthy, how WELL are you living?

Posted by: David Dressler, BA, RMT at December 25th, 2013 3:04 AM

To David Dressler, about a month later: Yes, absolutely. Everything you and everyone else who posted about low thyroid symptoms I completely agree with. I also want to mention that I read the complete study that's quoted above. What I find remarkable (and not in a good way) is that this study -- and all studies I read -- never measure FreeT3, our active hormone. They've finally started measuring FreeT4, but because of conversion issues (due to elevated cortisol or low levels of selenium), or due to excess reverse T3, there's no way of fully understanding this study's results. FreeT3 is the active hormone, therefore the one that relieves low thyroid symptoms. Without knowing levels of this most important hormone, how can anyone come to any conclusion at all? I'm just now climbing out of a period of hypoT, and I agree with those who question the value of life in a hypoT state. No thank you!

Posted by: Jodi Friedlander, N.C. at January 20th, 2014 7:38 PM

Jodi, thank you for your comments and clarifying the intricacies implied in that study and for actually reading it all. There is nothing like having an actual condition to motivate somebody to get informed and confront the contradictions involved in the field of related research.

I am in Canada a few years ago, if the doctor requisitioned tests for hypothyroid, you would get back TSH, T3, and T4. These tests were covered by the provincial medical system (were free in other words). Now the same requisition gets back only TSH, even if the doctor asks for T3 and T4. Why is this? The lab will say, "computer protocol" (as if that explained anything). If TSH is high, the patient comes back and they test for T4.If TSH is in normal range, no further tests are given. As pointed out: the range of so-called "normal" for hypothyroid is too broad. People who seem to have normal TSH or normal T4 can still have hypothyroid symptoms; in other words, they are hypothyroid. The range of all values should be adjusted in order to correspond with the symptoms or lack thereof. To get all three value tested, even if the doctor requisitions them, now we have to pay privately for the ones not covered.Even then, I have experienced the lab becoming very resistant to doing so. In my perception, the medical system here is deteriorating and becoming sneakily privatized. This is not good health care but rather wealth care.

Posted by: David Dressler, BA, RMT at May 29th, 2014 7:48 PM

Who or what is the source of this "Quote"... and is it authoritative?

Posted by: CR at July 6th, 2014 12:49 PM

my TSH is pretty high and my T4 too low. Means this is good? :P

Posted by: Ann at August 20th, 2014 8:19 AM

My T3 is quite high as well btw (previous post). So only T4 is too low

Posted by: Ann at August 20th, 2014 8:21 AM

Thanks for this post^^
thyroxine is very important for the health, both hyper/hypo can disturb the balance and also shorten your life. But when you look at the normal range which is very board.For example, the free T4, it is 9-23pmol/L, if you got 10 or 21, it is still in the normal range but the difference is 2 fold higher.
The normal range is for the whole population. The best level can always discuss.
For my opinion, keep the lower end in the normal range(ie.11) may be beneficial to extend the lifespan. Since the level still in the normal range, moderate exercise and eating healthy should keep the metabolic balance well and wont cause the health problem. To understanding your whole picture of thyroid health, the TSH, Free T4 and Free T3 should measure at the same time.

Posted by: Dennis at March 16th, 2015 10:01 AM

Hahahaha hahahaha. I have hypothyroidism and have had high TSH levels with normal FT4 levels and overt hypothyroid symptoms. Without getting into a conversation about how this happens, and leaving it at the fact that if your TSH is high with primary autoimmune hypothyroidism, at some point your T4 production became insufficient, and high TSH is a sign of a struggling body and central nervouse system, I would take a shorter, high quality life over an extended, fat, bloated, futile, mindless, half dead state called hypothyroidism any day.

In fact, I don't know anyone with hypothyroidism who would give up their medication for a longer life.

Posted by: ILoveSynthroid at March 5th, 2016 12:56 AM

I would also like to say, I have longevity in my family unrelated to hypothyroidism. There is nothing you can do to significantly extend your lifespan in any meaningful way. If you live to be 75 or 110, you are elderly during that time period none the less. What you should focus on is vitality, not lifespan.

My grandfather and my great grandmother both died when they were 91 but my grandfather had the gift of vitality and was active until a few weeks before his death, and my great grandmother had the misfortune of having become bedridden due to pulmonary fibrosis, which inhibited her ability to recover from a fall she took when she was 80, and spent the next decade in bed. She was very vocal in her discontent with having lived so long, much less in that state (though she did once admonish a friend for telling her it was ok to "let go", exclaiming "What are you talking about. I'm not ready to go!"

You also have to consider the isolation factor. Both my great grandmother and grandfather out lived all of their friends and most of the close family they grew up with. My great grandmother suffered with loneliness from this, even with people around due to the generation gap, and my grandfather didn't express it so openly but struggled with the loss of those close to him. I think it's like you are the last person at a party that ended long ago.

Maybe the problem of loneliness in seniors isn't so accute in societies where older generations and younger generations live together, or in societies where older people are seen as relevant, but in our isolationist, youth oriented society, being long lived often comes with the burden of lonesomness.

I'm in my mid 30s and work with a bunch of people who are in their early to mid 20s and while it's not that big of an age gap in the big scheme of things, nor a big generational culture gap, it's a big enough gap for them that they don't think to include me in their social circle outside of work as they do each other, even though I seem to be well liked.

So wanting to live very long, in a body that is not designed for it, with a mind that is not equipped for it, in a society that is not configured for it, is a little short sighted in my opinion.

Posted by: ILoveSynthroid at March 5th, 2016 1:53 AM

All of these very strongly worded personal experiences and opinions regarding health vs lifespan are possibly interesting but it is important that the science continues. Increasing our knowledge is never a bad thing. The more we learn about extending our healthspan and lifespan the better. And you are quite wrong, ILsynthroid, there are many things that can be done to increase healthspan AND lifespan. Thanks to the science being done.

Posted by: Neil at April 27th, 2016 8:09 PM

I do not find it surprising in the slightest that very old people have failing thyroid glands and therefore high TSH, they also have very wrinkly skin and a host of other issues. Correlation is not causation.

Posted by: Guy Baker at January 15th, 2018 1:46 AM

Correct! If you are testing only centenarians (those who have reached 100), you are only getting the data for their thyroid/pituitary function at THAT AGE. Their rising TSH may well indicate that they are in decline and are nearing death, as is surely true. The only way to validate this theory of supposed increased longevity with low TSH would be to follow people from a much earlier age, say from their 50's or 60's to verify that their TSH was high the whole time before they reached 100!

Posted by: Helen Anders at September 16th, 2018 6:43 AM

I was diagnosed with Hypothyroidism at 15, I was borderline obese (BMI 29.9) and had myxoedema, I am currently 25 years old, I've been drinking levothyroxine for 10 years, I have a normal BMI (22) and barely no symptoms, however, I drink 200mg of levo daily, and even though my T4 levels are normal, my TSH has never lowered, it is borderline high..which my endocrinologist doesn't understand (disclaimer: I have not been drinking 200mg of levo for 10 years, I have had to keep increasing the dosage to lower the symptoms)...I have to say however, my face/body has not aged since I turned 17. It is the reason why Ive been searching for an explanation, this seems as a highly possible answer as to why I'm not ageing.

I would also like to address something truly interesting, I can't tan at all. I have not been able to acquire color in my skin for years, I am very pale, rosy pale and direct sunlight on summer hurts like crazy, I have been using SPF+50 for a while now. For all of you wondering why, its because melanocytes produce melanin from tyrosine, so if your body doesn't have enough free tyrosine to spare, the melanocytes won't produce melanin and in time they will atrophy. I do have to say, even if we can't tan, we have a HIGH tendency to have melasma. So keep under the shade!!!

Posted by: Mara at December 4th, 2018 2:18 PM

My TSH=5.5 am 75 year old male, resting pulse, 45 beats/min, average blood pressure 105/65, Weight 144 lbs at 5 ft 7 in BMI 22.7, DEXA scan shows very dense bones Z score=6, Bod pod - fat at 7% , take no meds, very few supplements, have not been sick in to two years and have not missed a work out 20 months.
Waist = 30 inches, chest = 42 inches, triglyceride/HDL = 1.2 plus or minus .2 past 15 years
HOMA IR = .33 to .96 past 3 years, insulin sensitive per Joe Kraft pattern one profile
Is this due to genetics of the endocrine system inaction of bone hormones and the thyroid?
Seems odd - TSH went from 4.5 in 2017 to 5.5 in 2019.

Posted by: Daniel Durante at January 19th, 2019 6:10 PM

I have subclinical hypothyroidism (TSH 6.47, FT4 within range), no symptoms, and I do not take any medication. I am very healthy and at age 31 I feel like I've biologically aged slower than my peers. If I have learned anything about hypothyroidism, it is that there is a spectrum. It is not hard to imagine that a very symptomatic hypothyroid individual would suffer from lower quality of life and reduced lifespan due to the negative effects of hypothyroidism. However, for someone like myself on the mild and asymptomatic end of the spectrum, I can't help but wonder if I'm among the category of people who will "benefit" from this lifespan/hypothyroidism association if the science bears out. Only time will tell.

Posted by: John at February 15th, 2019 1:41 PM

TSH last week was 28.45, highest ever. Didn't check hormones but low normal last January. Male, 62 and very fit and strong. Take no drugs whatever and live very clean life, always have. No symptoms of hypothyroidism.

Posted by: WeirdWolfe at July 23rd, 2019 1:36 PM

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