Does the human lifespan have a limit?
nature.com
nature.com
Um, yes. A few years ago, the city government of Tokyo sent people to visit everyone who reported an age over 100, to see what they were doing right. What they found was a lot of pension fraud. "To date, the authorities have been unable to find more than 281 Japanese who had been listed in records as 100 years old or older."[1]
[1] https://www.nytimes.com/2010/08/15/world/asia/15japan.html
https://en.wikipedia.org/wiki/Blue_zone
Only Loma Linda seems like it might not be the result of fraud — and that’s only because it’s a haven for a kooky religion.
The whole life-extension thing is funny. I wonder if people realize what the world is going to be like 70+ years from now and how miserable it’s going to be for anyone over 100 who’s not rich? I think about my 95 year old grandma stuck inside the past 2 years because of COVID. I honestly think if I was that age I would have rather died in 2019 than be alive today.
My understanding of the parent is that it is rational to break isolation because the likelihood of death from other causes is so high already. If the hypothetical 90 year old lived alone (aside from visiting family), then maybe it might adds up that way. My response is that if the person is a community dweller with other old folks and everyone adopted this individually "rational" choice, then the average risk of death from COVID would be far higher because of the increased likelihood of transmission among the most vulnerable (probably why the parent might have gotten some pushback at the suggestion). (assuming this discussion is about restrictions pre-vaccine). Alternatively, if the hypothetical 90 year old moved in with the family, things might stack things up differently.
Of course, humans are long lived by natural standards, so the effect of CR on lifespan may be much smaller than in mice or worms, but I would still expect someone-who-fasts-regularly-but-isn't-malnourished to be healthier than an average Western person. Which usually translates into living longer.
Greek islands are one of the putative Blue zones, so this was the anchor of my comment.
I mean to say, diet is often not the only thing that sets these rural populations apart from city-dwellers. Not many office jobs in the countryside, I guess.
Watching them, and also my mother struggle with health issues at 73, has really changed my perspective on aging. I am very focused on enjoying my health now (at 47). Some people are spry and enjoying life up to their early 90s (my grandparents), but some experience health declines much earlier.
The stoic idea that "there will be a last time for everything" in your life (last time you go for a jog, last hike in the mountains, last time you can move without pain, last time you can travel, etc etc) is how I think about aging. I really try to enjoy the physical health I have now, and keep in mind that it will not last forever.
Yeah, I'd rather money be put into quality rather than quantity of life.
He owns part of the company that makes patented NMN which is just another form of NR which is a another form of very cheap Niacin.
He also owns part of the company that claims he is rolling back his biological clock.
That's not science, that's marketing and profiteering.
NAD production slows down with age and illness. All he is doing is supplementing what was produced more easily by a younger body.
There are a many other factors to aging, most of which cannot be changed (yet) by science.
My impression of Sinclair is that he likes public attention too much and often reports on work in progress with too much certainty, but results like this [1] seem to be fairly impressive.
Nowadays the small pains and aches go away in a few hours, like when I was some 15 years younger. But if I stop the supplementation, the situation reverts to the old bad standard within a month or so.
I also noticed some effect on my visual acuity.
I know this is N == 1, hard to measure precisely and subject to a possible placebo effect.
The key to NAD supplementation is the people who need it are older or ill.
There are a lot of other processes in such bodies that become deficient too.
None of the supplement methods for NAD, Niacin, NR, NMN will boost levels beyond what your body will use.
This is what the NAD cycle looks like, you can see NA (niacin) vs NR vs NMN are each closer to production but the end result is the same of what ends up in the blood vs organs like liver.
https://www.lifespan.io/wp-content/uploads/2019/06/NAD_schem...
There are wild arguments, even with scientific rigor, about NR vs NMN ability to get into cells. It is more likely that genetics matters and it varies from person to person and what else is in their diet.
How are you gauging “aging has paused or is going backwards slowly”?
All of which to say: there is absolutely no way you are possibly controlling for all variables here. Things off the top of my head that could help with exercise recovery, all of which are more plausible than some poorly tested supplement:
- Changes in exercise type - Changes in exercise duration - Changes in exercise intensity - Changes in exercise form - Weight loss - Sleeping more for better recovery
I find the first 3 episodes to be absolutely stellar and was engrossed the whole hour. Pretty good takeaways.
The more recent ones are a little contentious and, as he himself admits, a little pseudosciency. He even says that these supplements are marginally helpful, and perhaps the most beneficial things is literally to just walk after a meal. Partially as a result, and partially because the recent episodes's concepts weren't explained well, I found myself distracted.
Random-- he makes a comment how the FDA often prematurely bans things e.g. peptides, which greatly hampers researchers' access to these materials.
I am willing to bet it will do more for you than taking NMN.
Peter Attia has discussed this with folks who know a lot more than Sinclair and they have concluded there is no evidence it works. The number one thing you can do to extend lifespan is exercise.
Retirement isn’t my goal. I want to work full-time until my late 70s, and die in my early-to-mid-80s at the latest. In the meantime, I’ll spend my money flying, traveling, and on my apartment and a fast car.
We'll check back in a few decades...
It's sobering and makes it really hard to continue working in middle age.
And even if the problem can be solved, evolution doesn't owe you sufficient intelligence for our species to solve it.
I would choose to give my children financial benefits instead of years of late life medicine, even if I could afford to live over 100.
- Retirement age will likely be pushed until 80-85, to avoid long pensions.
- Young people will find it harder to get a job, even harder to get a well-paid one.
So yeah, currently there's a hard limit - around 100, more or less, but with life seldom being worth living after 90. I really wish we'd start investing in breaking this. I'll happen at some point, the only question is when, and I'd think it's obvious why we'd want it earlier rather than later. But some facet of our psychology makes it very hard to think about this in hopeful ways.
- average person who dies at 80. Middle point in his life at 40. At 20 the person has already lived a 1/4 of his life.
- imagine a supercentenarian who dies at, for the sake of examples, 120. This person at his 60s is like the average person at his 40s! If we consider that for the average person his “sweet years” end at 35, a supercentenarian’s sweet years end at 51!
Then the real fun starts.
I just turned 40, and feel like I’m finally hitting my stride.
My worst day of retirement was better than my best day of working or education.
Am I going to win races against people half my age who are in peak fitness for their age group? No, of course not. But I can physically do far more at 57 than what I could do at 25 with respect to running. Many people can alter the course of their health trajectories at nearly any age but it requires consistent effort and often ignoring the messages of vested societal interests telling them otherwise.
That’s why I mentioned sports: even people who have worked out their whole lives, at the top of their sports, see declines in physical performance as they age.
Congrats on getting in shape. Relative improvements in physical fitness are beneficial and possible for many people. But it doesn’t reverse aging.
Recovery times are shortest in children - and become very significantly longer even at ages where maintaining muscle mass isn't too much of an issue. Maximum speed peaks with strength in your mid/late 20s & declines from there. Endurance seems to carry on increasing in to the late 30s & declines very slowly, plenty of ultrarunners, Audax cyclists and triathletes in their 40s/50s.
What does that end up looking like though, Logans Run? :D
I can't see a voluntary version of it working because of the very psychological issue you mention, we are inherently self preserving creatures in all but the most unbearable conditions. The other thing with these very personal choices, is that you just don't know until you get there - how do you or I really know if life is not worth living after 90, personally? we haven't experienced it.
I remember my Grandfather, when he was younger, specifically saying he'd rather die than live with a certain disease he saw some other people getting - which wouldn't seem like an unreasonable opinion to most people. Yet after gradually developing the very same disease later in life he certainly was not of the same opinion while he was still lucid... That stuck with me, it's easy to speculate about things you haven't personally experienced, and easy to be wrong about your own state of mind in that situation.
I would consider it good news if old people had to live with their decisions and problems they created instead of leaving it to the next generation.
The people inheriting the problems we started making 40 years ago before they were born even, still have very little say.
Until relatively recently when I switched to believing that there's actually a biological cause for this: sub-clinical forms of dementia. We just get old and lose capacity for meaningful change. We keep functioning, but the decisions we make are based on what we already learned about the world 20-40 years ago.
Which means it's fixable. I don't want a world where I replace my father and am replaced by my children. I want a world where my father starts acting like a valedictorian again, but with a life of experience behind it.
As we move through life, we inherit bias and experience and no longer have fresh perspective. It's possible to get wiser with age, but it's also likely we will gain experience that hold us back, such as hatred and trauma.
Here's the thing: the newer generations are also going through this process too! They are not necessarily better. They might have less trauma, but they also have less hard won experience.
Yes, basically as a fellow commenter argues. Thank you for the link.
But in reality, there's opportunity cost to trying to extend your lifespan, it's all the money and attention and other resources that could have gone to improving other much more certain-rewards problems.
In other words, your thought experiment is a fully general purpose argument for any investment. It's conclusion is that you should _always_ go for the investment no matter what the opportunity costs.
Example (1) - We should expand the data center from 80 servers to 200 servers
= Why? our loads are not high, we should instead focus on improving the product
- Well imagine if we already had 200 servers in the data center, would you scale it down to 80
Example (2) - We should invest in renewable energy
= Why? nuclear power is much more certain and mature
- Well imagine if we already had renewables, would you phase it out in favor of nuclear?
In both cases, you're completely missing the point of your opponent by the "Imagine if we already had" maneuver, we don't, that's why your opponent is against it, it's a risky investment with uncertain rewards and plenty of same-utility alternatives (in the opponent's view).
So we live 80 year lives, but with only about quarter of that really giving all we're capable of, and a fair share is being dedicated to raising children. Living an extra 20 years isn't a perk - it literally doubles our most productive years. Living an extra 40 years with most forms of dementia fixed? That's almost unimaginably more productive, and unimaginably richer. Both on an individual level (working+learning more = earning more), but as a society.
You mentioned "when it's more worth living". Not sure what context you're coming from, but life is a lot more worth living in its second half, simply because you know more about how to live it, and have the means to do it. The only problem is you're getting old and senile.
Edit: please don't downvote somebody asking questions.
After about 25,000 years or so, his brain becomes "full," and he can't remember stuff, anymore.
[DISCLAIMER: It's been a long time since I read the book, so some liberty has been taken in the Cliff's Notes version]
The implication being that when doing statistics with a large number of data points, you often see several outliers that are way outside the curve. In the case of age, the tail of the curve falls to 0 very quickly.
The average speed for an F1 race might be 250Km/h. This doesn't mean any of the cars can ever hit close to 500Km/h. Just that we eliminated most of the reasons cars were slowing down and were left with the fundamental limits of the car's speed as dictated by it's engine, grip, aerodynamics, or weight.
In a Stone Age society you would definitely find people twice as old as their group's average lifespan. But that average lifespan would be rather low.
There always are old adults present, but they are rare.
From your nickname, I gather you are a Czech. I can link an article about analysis of an early medieval cemetery in Rajhradice to you. 244 buried people, 220 skeletons were successfully analyzed for age. No one over 60, eight people over fifty (almost all women).
https://karolinum.cz/data/clanek/5704/Praehist_34_1_0007.pdf
Life expectancy at birth was around 30-35 for at least the several preceding centuries in Europe.
https://publishing.cdlib.org/ucpressebooks/data/13030/tf/ft0...
Basically, until the 19th century, between 25-35 % of people lived to be 60 or more. In the 20th century, this grew rapidly up to 90 per cent.
80 y.o.-s would be very rare even in the 19th century, while now about half of the population lives to be eighty.
Note that this is the Modern Age. In the Middle Ages, survival would have been worse. A more primitive agriculture, less developed long distance trade and fewer staple foods (no potatoes etc. in Europe prior to the Columbian exchange) would result in frequent famines that took the infirm first.
Things would be yet worse in the Early Middle Ages, the period of frequent nomadic incursions and warfare in most of Europe. At least the High Middle Ages were relatively peaceful compared to the period before.
Human mortality varies widely, but one relationship seems constant: death rate increases exponentially with age. A mortality table from 2011 shows males age 40 have a death rate of 2.1 per thousand; at age 100 the death rate is 357.9 per thousand. That's an increase of a factor of 170 over 60 years, or about 9% per year. Mortality graphs are almost straight lines on semilog plots. Different groups (men versus women, different countries, etc.) show different y-intercepts but the slopes of all these mortality curves is about the same.
From this we can deduce that males aged 104 (in this sample) have about a 50% chance of dying within the next year: another way of saying their life expectancy is 1 year. Mortality rates which increase 9% a year, will double in 8 years. So a male aged 112 will have a life expectancy of 6 months. At age 120, 3 months. And so on.
That's why we don't see many humans older than 110 or so, and why no one has lived past 130.
You won't get it until you pass a certain year, where like an old car, things suddenly start failing one at a time where everything was fine for years.
Diseases, illnesses like Covid can cause radical aging, one year you are turning 55 but Covid now makes it like you are 65 because all your organs, body and brain have been stressed and damage beyond self-repair.
And endless common problems have no cure, ie. Raynalds, Small-Fiber Neuropathy, no cures, no prevention, many people get them when they are older.
Quantity of life is meaningless without quality of life.
We may reach a point where many people live past 100 but that will be because they are genetically engineered from birth to have great health.
Doesn't help we are poisoning the water and air, willingly and openly, not in third world countries but right here in USA like Texas: https://www.fastcompany.com/90692691/this-super-detailed-map...
Take the guy with a pig heart and extend that tech 60 years out, then take the richest man on earth who will spare no expense for him and his statistically significant pool of people willing to undergo this experiment with him. The brain and circulatory system and are going to be some of the limiting factors to this approach, but in my uneducated opinion would have a good shot at creating the oldest people to live, albeit with a high dropout rate.
However, I'm skeptical that this will extend maximum human lifespans. The transplant surgery itself is extremely risky for elderly people. Consider the risks of cognitive decline caused by general anesthesia, post-surgical infections, blood clots, sarcopenia caused by bed rest, etc.
By the time we have consistent birth records we will also have better treatments for chronic diseases.
There is likely an upper limit, as I believe oxygen itself is corrosive, but even then a gradual but more comprehensive repair process should help.
'My spirit shall not abide in man for ever, for he is flesh; his days shall be a hundred and twenty years' (Gen. 6:3).
As a non Christian this always baffles me.
They were just people like us; right sometimes, wrong much more often, but in their case, lacking the tools to verify most ideas.
Now, they also believed the mind was porous and spirits could flow in and out of your head, that you could predict the future by looking at bird patterns, and other nonsense. But then again, have you talked to any Wellness enthusiasts lately?
So yeah, this is pretty cool, but it's also a warning. Everything people did a few centuries or a millennia ago is still in human nature.
No, it will prove that Biblical literalism is false, but that's a novel minority doctrine in Christianity that is already disproven by (among other things) the two conflicting creation sequences in Genesis.
“It wasn't literal [, where convenient]”
“The New Testament retcons this, ignore inconvenient or contradictory things in the Old Testament”
“It was translated wrong in ye olde English from Greek and Hebrew”
and finally conclude “it’s open to interpretation”
there, I saved you the whole conversation.
For example, in law one could fairly comment that:
1. Literalism isn't absolute - e.g the old British legal tradition of using England to refer to England & Wales
2. Laws supersede one another - new laws overriding old ones, constitutional laws taking primacy
3. Translation challenges occur - when documents like birth/death certificates, immigration papers, college transcripts, police clearances, marriage licenses, divorce decrees and etc are submitted in foreign countries for acceptance by courts and other institutions as legal record.
4. There is space for interpretation - See laws deliberately leaving room for interpretation with phrases like "reasonable force"
Despite these challenges, textual critics of legal writings are often able to successfully decide whether a given statement about a text is correct/incorrect.
On immortality, my thing is actually psychologically framing it were it to become a reality; it's entirely inconsistent with everything we have ever known. I think mortality has a purpose within the context of life. And there's literally limitless implications it would have. To me it seems like the most inhumane pursuit conceivable.
What is the difference between not investing in life extension research and just putting a pillow over the face of a million people?
On the obverse side, there's a string of unavoidable consequences and complications that are unfathomable. Once such a technique becomes available though, that culpability becomes real. And on many complex levels. It's a fools errand cartooned in the purile mind, and far more responsibility than humanity will ever be capable of justly handling.
The trolley problem would like a word.
You want people to die. I think that is horrendous. Our world views seem to be fundamentally different, is there any point continuing this conversation?
If everyone lived like the average American today, the maximum sustainable population is about 70 million humans (give or take a factor of about 2), even if they’re all mortal.
Conversely one can conceive a green tech and policy future which is compatible with having trillions of ageless humans living comfortably in what are currently deserts while the rest of the world is maintained as a nature reserve.
Gilgamesh encodes myths and lessons for human race with no technological access to 'immortality'.
I think mortality has a purpose within the context of life. And there's literally limitless implications it would have. To me it seems like the most inhumane pursuit conceivable
There is no purpose but what we make of it, and why it would be inhumane? It's inhumane to watch people you loved die.
Metaphors taken literally. Literality taken metaphorically. Esoterica interpreted conventionally. Guiding the hand of the translator. Mistranslation compounding over the iterations.
Any useful knowledge must get lost like dust in the wind.
If it is up to the reader to decide which is and which isn't a metaphor that should not be taken literally, than the text is no better than the reader's capability to distinguish metaphors from facts to be taken literally, is it?
It's a failure of the medium. It requires an expert to interpret properly.
And most of us aren't that. And some of those in charge of translation and interpretation aren't that either.
right, so if a biblical number is wrong we find some reason to excuse it.
Most religious texts can just be accepted as "good human practices summed up in 4 pages".... but instead they have to be made into movements, and groups who believe 'my team is right and yours is wrong'.
My view is that - just as there are many tongues, religion of the same Creator is presented differently to resonate with those localities.
Why isn't civilization really moving past the stories to simply focus on the main points that are being relayed?
I believe dogmatic believers miss the forest for the trees; the non-believers use the trees to disregard the forest.
Some stories can be called prettier, more compelling, more useful than others...
Most are consumed unconsciously. In childhood. And form the foundation of reality. So to mess with it can be ... disturbing.
if they're creating earth, then how could it be that they're using earth days? (allegedely, earth is just getting created)
also, what if a day is a rotation around a body's axis, then what about a solar day (the sun spins around itself once)? what about a galactic day?
Because this is a myth from thousands of years ago, and "scientific" accuracy wasn't relevant, much less possible. Read any ancient creation myth, or most ancient myth at all, it's closer to dream logic than anything remotely realistic. They meant earth days because those were the only kind of days they were aware of, and because there's no reason to believe they made the story more complex than that.
Things can be complete fantasy yet logically consistent.
> there's no reason to believe they made the story more complex than that.
you seem to be working under the assumption that because they lived long ago it must follow that they are simpler or in some sense "dumber". (i.e. I claim you believe that "in the past every man was a simpleton compared to a modern man")
alternatively, if in the past they were using dream logic (which you also seem to belive ought to be expediently discarded) couldn't they also dream about other varieties of days? or do they need to have a modern scientific outlook in order to even be able to consider days of different durations?
>alternatively, if in the past they were using dream logic (which you also seem to belive ought to be expediently discarded) couldn't they also dream about other varieties of days?
I don't know why you're being so defensive, or why it's so important to you that Genesis be justified rationally. If you want to believe the ancient Hebrews based the days of creation on galactic rotations, go right ahead. It would just be odd, given that no one back then knew what stars, planets and galaxies even were. The timeline still wouldn't make any sense
And sure, they could probably dream of other varieties of days, whatever that means, but again - why have a narrative about six days refer to that rather than just six days? And why did they never write this dream down, or mention it? Surely they would have considered that a divine revelation from God.
The story says days, it means days. Regular human Earth days. There's no reason to believe otherwise.
If you are dedicated to the idea the writer of the bible wasn't human then you might go down the rabbit hole of alternative explanations.
Look if you want to accept the Bible as true then acknowledge what it is warts and all. Old Testament God kills kids for mocking someone’s bald head (Kings 2:23-24), that’s your religious text. Feel free to believe it all happened as written, or do what almost everyone does and ignore most of it.
1 Kings 7:23
And he made the molten sea of ten cubits from brim to brim, round in compass, and the height thereof was five cubits; and a line of thirty cubits did compass it round about.
This verse is not specifying a maximum human lifespan, but the period of probation in which God's spirit would strive or plead with mankind before their judgment by the Flood. This is the period during which “the longsuffering of God waited in the days of Noah, while the ark was a preparing” (1 Peter 3:20).
Genesis records numerous descendents of Noah who lived longer than 120 years (see Gen. 11:10-25). Lifespans did decline rapidly after the Flood, however, and it was recorded in Psalms that “The days of our years are threescore years and ten; and if by reason of strength they be fourscore years, yet is their strength labour and sorrow; for it is soon cut off, and we fly away.” (Psalms 90:10).
Even today with our advanced medical knowledge and technology, life expectancy is still typically between 75-85 years.
If you're a Christian, doesn't this mean that you believe that they are both still alive and are world's oldest humans
As an athiest, there's nothing baffling here. Someone guessed 120, perhaps they even knew someone that lived that long or near that long. This sort of "they got this right!" thing happens in a lot of other religions (look up "proofs of the Koran" for examples from the Islamic perspective). Even mormons got it right that some ancient american civs discovered concrete.
It must have been obviously inaccurate even when it was written.
I don't understand how this is in any way baffling. There were plenty of humans around for people to observe when the bible was being written, and some of them probably lived to be quite old.
I have never seen a supercentenarian myself, and I have been in a lot of nursing homes. I only know they exist because of the internet to be honest.
Could it be that birth is nothing but a glorified error correction with two unrelated dna to ensure probability of damage is low. If so, can the same be done with two unrelated dna pairs again again and the result applied back to a living human.
Probably it's just survivorship bias. When a organism has trillions of cells, it can afford to have some fraction of them damaged. It just carries on with degraded function. When it has a single cell, all essential genes must be functional, or it dies before anyone knows there was a pregnancy. It's a bottleneck. The zygotes that made it to birth are the ones lucky enough to receive a minimally viable set of undamaged genes from both parents. Most couples try a lot before one successfull pregnancy.
Selection pressure plays a large part here. Waterbears (tardigrades) have exceptional DNA repair mechanisms — far superior to ours in some ways — because they must survive constant dehydration and rehydration cycles. Without the ability to repair what we would consider catastrophic DNA damage they'd have gone extinct long ago.
So, it’s probably like 250 years with intensive DNA repair effort.
Error rate during active lifespan is real. Gamma ray probably is the largest contributor of active (or even inactive) DNA being disturbed.