There's no limit to longevity, says study that revives human lifespan debate
nature.com
nature.com
The low-hanging fruits of obesity, heart disease, and diabetes are calling to public health far more urgently than this pie in the sky limitless life.
Isn't the question whether or not we can affect the odds here? If we can increase it to 75:25 at this plateau, then we also are also increasing the age longest lived of these people are predicted to live for immensely, and the last person of this example group of 1 million starting at age 105 you give would expect that last person to die not 10 years later (at 115) on average as with a 50:50 mortality, but around 48 years later, at 153. Every slight change in that mortality rate affects that long tail quite a bit, relatively speaking.
I for one believe that might have an immense effect on how people view their health and longevity. If people believe that taking care of themselves might give them many decades of additional life instead of a few years, that could lead to a wider shift.
In [2]: def reduce_pop(pop, prob):
...: if pop <= 1:
...: return 1
...: return 1 + reduce_pop(pop * prob, prob)
...:
In [3]: reduce_pop(1000000, 0.5)
Out[3]: 21
Please correct me if my math is wrong or if I'm miss interpreting how to calculate this.
I did have the wrong number of years for 50:50 though, it's not the 10 I stated. This problem is the reverse of binary doubling, and I knew 10 bits are a needed to get to 1024, and my brain just sealed out thousand and million. It takes 20 bits to get to over 1 million, so 20 halvings from exactly 1 million should get you to less than 1.
Still, it's definitely worth it to continue research along these lines and plenty of other ridiculous lines. Even if they don't come to anything. We have such a tremendous abundance of intellectual capacity as a species. If we dedicate all our intellectual capacity to solving the low-hanging fruits in healthcare (or to increasing the click-through rates of ads, among other things) it would require us to allocate many people to no task at all, just because there was already an excessive abundance of resources already dedicated to the tasks.
It's a little fun and encouraging to think about, but the more people there are alive, the more important unimportant things become, because with more people there are more problem solvers.
I really appreciate this perspective. More people is fundamentally a good thing. Some would vehemently argue otherwise, but I believe the problems they bring up come down to a calculus that depends first on other things, like profit vs. environmental stewardship, etc., not primarily the birth and death rates.
Seriously, until we don't reach 100% of well-fed educated people, demographic growth will be more of a problem than a solution to anything.
- What do you consider a bullshit job?
- What level of education would you prefer everyone in the world have? Basic literacy, high school, college?
- What problem will be solved once everyone is educated (at the aforementioned level)?
In Bullshit Jobs, American anthropologist David Graeber posits that the productivity benefits of automation have not led to a 15-hour workweek, as predicted by economist John Maynard Keynes in 1930, because of "bullshit jobs": workers who pretend that their role isn't as pointless or harmful as they know it to be. Graeber contends that more than half of societal work is pointless, both large parts of some jobs and, as he describes, five types of entirely pointless jobs:
- flunkies, who serve to make others feel important, e.g., receptionists, administrative assistants, door attendants
- goons, who act aggressively on behalf of their employers, e.g., lobbyists, corporate lawyers, telemarketers, public relations
- duct tapers, who fix problems that shouldn't exist, e.g., programmers repairing shoddy code
- box tickers, e.g., performance managers, in-house magazine journalists, leisure coordinators
- taskmasters, e.g., middle management, leadership professionals
Graeber argues that these jobs are largely in the private sector despite the idea that market competition would root out such inefficiencies. In companies, he credits "managerial feudalism" as employers need underlings to feel important.
In society, he credits the Puritan-capitalist work ethic for making the labor of capitalism into religious duty: that workers did not reap advances in productivity as a reduced workday because, as a societal norm, they believe that work determines their self-worth, even as they find that work pointless. Graeber describes this cycle as "profound psychological violence".
Graeber holds that work as a source of virtue is a recent idea, that work was disdained by the aristocracy in classical times, but inverted as virtuous through radical philosophers like John Locke. The Puritan idea of virtue through suffering justified the toil of the working classes as noble.
As a potential solution, Graeber suggests universal basic income, a livable benefit paid to all without qualification, which would let people work at their leisure
If we're allocating a portion of production to all people, but have finite energy resources (e.g. current state), then there exists a range of population (and demographics therein) where this is practical.
In that in non-communist allocation systems, if one does not produce value (somewhat arbitrarily defined, but usually semi-attached to actual value) then neither one nor one's children eat.
UBI fundamentally changes this, in that hypothetically people could do nothing (and reproduce), thereby eventually exhausting available energy resources.
If your point is that everything has an absolute carrying capacity, then agreed. But here I'm assuming UBI is implemented before resource scarcity is truly eliminated by technological progress.
Thereby leaving the equation in an "It balances, but only if these percentage of people work, age demographics don't get too out of whack, and population growth falls in range" state.
The level education people should have is the one that allows them to become useful problem solvers. Depends on character and domain of problems considered.
I am not saying reaching 100% education will solve a problem. I am saying that before that point, population growth will feed more problem making than problem solving
"Fundamentally," perhaps. In all other cases, not so much. Having more people in my house or even in the city where I live would be a bad thing.
Vastly more people die each year of age-related causes than obesity, heart disease, and diabetes combined. It's an unrecognized holocaust inevitably terminating the potential of all humans on this planet, and it is going entirely unrecognized because if you work on solving aging you are a crackpot, whereas "obviously" obesity, heart disease, and diabetes are more deserving of our time and grant money.
I would agree with you if the common experience of old age was positive and healthy; but it seems to me that the priority for research should be to alleviate the problems and suffering we will all face should we be lucky enough to get there, especially now that the majority of people are lucky.
Perhaps healthier older people will live a lot longer as well?
It’s not positive and healthy because you age. You fix aging and people will have a physical age of 25 forever and do all sorts of fun things with perfectly capable bodies. That’s the point.
I don’t know what sort of counter factual world you are describing where we have “alleviated aging” but people still age...
My daughter would say "ew"
Oncology + new genetic tools (just sequencing, not even CRISPR/CAS9) is making amazing progress.
Things that would have been a death sentence 20 years ago now have reasonably hopeful mortality rates.
No, it's not. Cancer is just a form of malfunction of cellular machinery, and as such, can certainly be mitigated or cured at some point. There's already lots of promising research in eliminating it, such as by re-purposing viruses to program the body's immune system to recognize and eliminate the cancerous cells.
It might require artificial intervention, but I believe cancer will be mostly eliminated before too long. And artificial intervention shouldn't be a problem: we have to do this on all our other machines too, we just call it "repair" or "maintenance". There's no such thing as a machine which never needs maintenance from an external source.
Is it just me, or is this just bad logic?
It just sounds dumb because it doesn't take into account any physical limitations that would make the curve reach zero.
People have a 50% chance of dying each year over 105 translates to there is no limit to longevity?
Also, the critic in me makes me want to see the actual distribution because I would think there is a tail effect going on and a small group of people are just genetically living much longer.
That being said, it seems that reading just about an scientific study these days makes you wonder if those doing the publishing understand data analysis, statistics, etc. It seems that too often they find some date, retro-fit a conclusion, ignore the flaws and holes, but still publish because they know the "journalists" won't figure it out either.
And then science complains about the public not buying into ever word science mutters? I don't get it.
Death rates increase every year due to naturally occurring mechanisms in the body. Consider those mechanisms as a function with the body as a parameter and the output as a more aged body (or rather a body with higher probability of failure).
If the body reaches a point where the death rate ceases to increase year per year, it would suggest that those same naturally occuring mechanisms, thought of as a function, approaches some asymptote.
Note this doesn't necessarily mean you stop aging (in appearance), just that your body's rate of failure no longer increases. This suggests that if the reasons for failure can be treated properly, perhaps the body can remain in that equilibrium state indefinitely.
This study provides some preliminary evidence that such an asymptote may exist in the body's natural mechanisms. Both controversial and exciting. Worth exploring further.
Because there are essentially two things that kill you. Either you die of something you get, or you die because your body wears out (as others have pointed out, we know body systems wear and become less effective with aging).
Therefore, if mortality stops increasing with respect to age at a certain point, but we know the body is accumulating additional wear that makes it less resilient, there must also be a corresponding decrease in mortality risk with respect to random things killing you.
So essentially, if you're 100 already... you might have a statistically smaller risk to die from heart disease, cancer, etc than someone who is only 92.
Agreed. I assume older people are receiving higher levels of care, and therefore have a lower risk of dying from random things.
For example, someone age 100 has a small chance of falling and receiving a life threatening injury when they go to get a glass of water from the kitchen. Someone age 115 might have a smaller risk, because they're more likely to be in a wheelchair, and therefore will not stumble and fall. Do they need to change a light bulb? The 100 year old might try to stand on a chair and risk falling. The 115 year old will probably have full-time care, and push a button to alert someone else about the light bulb. Older people usually travel less often, so their chance of dying in a car crash starts to decrease. They're no longer diving with sharks, so shark attack deaths decrease. They're less likely to be outside in a thunderstorm, so lightning related deaths decrease.
Some of those examples are a little silly, but I think the idea is right. When you go from 100 to 115, you decrease your risk of dying from random things (usually because you're no longer doing those things), but you increase your risk of dying from age related factors. These two cancel each other out, and the chance of dying on any given year appears equal. This would mean the study is wrong, and there is a limit to longevity.
So sooner you start the "treatment" the better as it is more fun to stop aging around 30 than 70 (which currently is already a thing, people aging a lot better than their parents).
One of two things may be true:
1) As we age, mortality rate increases until certain
2) As we age, mortality rate increases, and then levels off at some point
The latter doesn't mean you'll live forever: you're still already rolling the dice at the highest handicap every year. But it does mean there's no fundamental age everyone MUST die by (aka "live forever", if you're one in a billion).
The more interesting differentiation between the two, and the reason biology is interested in the question, is as an answer to "If we want to maximally prolong life, what do we do?"
If the flattening risk (option 2) model is correct, then we could extend life very far indeed by simply preventing people from dying of things that normally kill them by age 85 (e.g. disease, cancer) and then provide them with high quality medical support (to best fight the risk of their expiring from "normal" causes, e.g. accidents).
On the other hand, if it's ever-increasing risk (option 1), we should instead spend our effort at untangling the microbiology mysteries at the root of aging, and see if we can instead re-engineer systems to not work the way they currently do.
Or as my father (PhD in pathology) quips on the whole matter, "At some point, old folks are past the point that all of things that normally kill people would have killed them. And by virtue of still being alive, it's probable they're more resistant. We say they've reached escape velocity."
The "mortality rate" increasing then flattening out is just this curve reaching its peak then declining. The math of this is easy enough to figure out so not sure why there is a mystery amongst biologists about it.
I guarantee that once you understand how universal and simple the phenomenon is that's going here on you will be stunned at the ridiculousness of this "lifespan controversy".
Obviously, there are a lot of "ifs" here but the result seems interesting and suggestive.
Once you get to 117 years old, there are only a few people worldwide that can be used to determine that survival rate, and those people are already subject to a selection bias of people that are exceedingly long-lived.
By analogy, is a continually trained neural net the same as a previous version of itself? Is it a different one, especially after a long time? Did the old version end/die by continuous accumulation of changes?
Looking at the Wikipedia list of longest-lived people (https://en.wikipedia.org/wiki/List_of_the_verified_oldest_pe...) I get the impression that the top two (Jeanne Calment and Sarah Knauss) don't fit, though I know that the case of Jeanne Calment is very well documented.
Even if the chances of surviving another year did stabilise around 50% after the age of 100, say, you still wouldn't have enough people living beyond 130 for you to be able to measure with reasonable accuracy the mortality rate of people aged over 130. So the hypothesis that a person aged 140 would still have a 50% chance of surviving another year would be totally untestable.
If you think about it, there's also no hard limit for how tall or how short an adult human could be. Except the limit of zero for the height. Again, beyond a certain point there will be, in practice, no data available for testing any hypothesis about the distribution.
I content that there are no limits: however old you are, you have a non-zero chance of surviving another picosecond. The product of a finite number of non-zero real numbers is non-zero, therefore...
Some people may wish to retort that at some point these numbers become so small that they are no different from zero in practice. Those people are probably not mathematicians. They're not wrong, either, of course, but they're not making a valid argument for there being a limit.
There's no limit for the number of successive heads you can get when tossing a coin, either, though you won't in practice see more than a hundred if it's a reasonably fair coin. If there's no limit in that simplified, mathematical situation, does it make sense to hypothesise that "there is a limit" in the case of highly complex biochemical processes?
This is all very philosophical. It doesn't help us to estimate the chances of a given person who is alive and 115 years old today (there seem to be about five of them) one day breaking Jeanne Calment's record of 122. Are any bookmakers taking bets?
The fact that chromosomes get shorter during DNA replication is a scientific fact. Chromosomes have padding at the end called telomeres that provide a buffer from the 'useful' DNA. There is an enzyme that can lengthen telomeres, and its of great interest to scientists interested in extending human life.
There is almost no chance that mutations:
a) regularly occur in such a way that makes the chromosomal DNA longer, especially in a way that offsets the base pairs lost during every transcription.
and b) occur in the telomere area of the genetic code, after all the useful bits of DNA.
If mutations did occur at a rate that would counteract the shortening of the telomeres, the rest of your genome would be mutating so quickly you would almost certainly die rather quickly.
There are a whole host of other reasons why what you wrote is nonsense, and I don't have the time or the space to address them all. There is literally no fact to what you have written. It is clear you don't have even a rudimentary understand the biology of genetics. An understanding of math doesn't preclude the need for understanding the actual mechanism of how things work.
The following articles are a useful primer to understanding the flaws in your reasoning:
Okazaki Fragments: https://en.wikipedia.org/wiki/Okazaki_fragments
Telomeres: https://en.wikipedia.org/wiki/Telomere
Telomerase: https://en.wikipedia.org/wiki/Telomerase
DNA Polymerase: https://en.wikipedia.org/wiki/DNA_polymerase
DNA Replication: https://en.wikipedia.org/wiki/DNA_replication
> almost no chance
That's my point, really. It might not be a terribly interesting point, but you're conceding it, not refuting it.
Does genetics actually provide a useful estimate of the probability of someone reaching the age of 123 years? I mean: something a bookmaker could use? Is there any evidence that telomeres are practically relevant to the longevity of humans in particular, as opposed to organisms in general, some of which live very much longer than humans?
I humbly suggest that you turn down the pomposity a tiny bit. Read what you wrote there:
> There are a whole host of other reasons why what you wrote is nonsense, and I don't have the time or the space to address them all.
What kind of impression do you think you're making?
I provided resources for you to educate yourself. If you believe that it isn't a good use of your time, that's exactly how I feel about addressing the points you made beyond broadly saying 'this won't work, here are resources that address this on a level which you can understand.'
In this case 'almost no chance' is somewhat analogous to shuffling a deck of cards and finding them in order by suit and value, and then shuffling them again and finding them in reverse order by suit and value, and repeating that feat 10 times over.
The length of a human's telomeres when they are born is about 11k base pairs. Chromosome 21 is the shortest chromosome, and has 46.7 million base pairs. That means with random chance a mutation is 4200 times more likely to occur in the coding region of the chromosome than in the telomere.
Due to the way DNA Polymerase works, you will lose 20 base pairs of DNA on every replication. Ignoring everything about rate of mutations and the likelihood of insertion mutation, this means your chance of lengthening your chromosome through mutations is (1/4200)^20, or 1 in 2.6x10^72.
The odds of shuffling a deck of cards and having it come out in suit and value order is somewhere around 1x10^68.
That's using a best-case scenario as an example. Chromosome 1 has more than 5 times as many base pairs as chromosome 21, and you'd literally need to have this happen on every single chromosome every single time you had cell division.
There are a few caveats:
1) The non-coding region appears to be less useless than previously assumed. There are still 'highly preserved' areas in non-coding regions. If a section of the genome is highly preserved, it means that a mutation in that region probably results in death/non-viability of the organism.
2) We know the rate of mutation of the genome. If random mutations were really adding enough base pairs in the telomere region to lengthen it, the genome would be growing at an incredible rate.
There are a lot of reasons why it's also implausible, but they have to do with the amount of energy in a bond, etc. and other biochemistry stuff that I'm not qualified to comment on.
That being said, the shortening I am referring to is the simple mechanical fact that we know with absolute certainty that your chromosomes shrink by 6 base pairs at each division. This is a simple biological fact.
"Not being mathematicians" is exact what you want when making predictions about the real world.
In the terms of probability aging distribution becomes memoryless for very old people. This would mean that the remaining lifespan for really old people would follow exponential distribution. Just like with radioactive decay, you could determine their half life. The half life could be as short as one year.
>At that point, the researchers say, the odds of someone dying from one birthday to the next are roughly 50:50
It does in flies, and there is very clear evidence for that. The evidence in humans to date is very sparse, and where people have done good work on the numbers, they have not seen signs of a plateau. So in that sense, that people have found a larger data set that shows it, that is fuel for the fire.
No-one has the slightest idea as to how you can balance the fundamentals of reliability theory with a late life mortality plateau. If damage is accumulating, and no-one really believes it stops accumulating, then your risk of mortality should keep on going up. What sort of mechanisms in a highly damaged biology could buffer that underlying reality? And why in very late life versus other times?
None of this, of course, has anything to do with efforts to treat aging or extend human life. It is an academic debate that will likely fade out before answers are found, made irrelevant by the advent of ways to treat aging and its causes. Methods of extending life will work by putting off or repairing the very damaged state. There will likely never be a large multiple of the present count of exceptionally physiologically aged individuals. Rejuvenation therapies are just around the corner.
If it's true for things, it makes sense it might be true for humans.
Obviously, this kind of treatment wouldn't at first be widely available even if it worked. So how do we decide who gets it?
In general, I think the economic incentives for medical tech are fucked up.
Being 40 is pretty alright. I'd rather live in the body of a 40 year old for 40 years than the body of a 25 year old for 25 years.
Humanity needs to fundamentally change the way it consumes goods if we want to sustain populations that cannot die. There is also the question as to who would get such treatments? The rich? Everyone?
Kim Stanley Robin's book Red Mars deals with a lot of these issues in a fiction future where human colonize mars. It's a really good book.
Doesn't mean it can't be done, but it's hard to change an economic system that is embedded into our culture.
http://www.pewresearch.org/fact-tank/2016/04/21/worlds-cente... claims there are about half a million centenarians now. At 50% mortality/year, half of them should be between 100 and 101 years old, but chances are it’s higher because the world’s population was growing fast a century ago.
That would give us one or two 118 to 119 year olds 18 years from now. I wouldn’t rule that out.
1. there are few, as the world has 7billion++ people today and 120 years ago it was around 1 billion. You certainly are not going to meet them.
2. Someone that is still sane past 100 years will not care about bragging his age to us younglings.
3. Finally, we don't ask these people their age. And when we do, we don't believe the answer.
There are some histories of people with more than a hundred year. Li Ching Yuen[1] was a Chinese herbalist that lived more than 250 years.
Ah! Clearly the human age register is only 8 bits and when it overflowed his body crashed.
Try to plan ahead a little better when designing human 2.0 God!
This skepticism is borne from living a life of being gaslighted and conned in a high-demand religion, and breaking away. I don't doubt there are occasionally a few long-tail events that skepticism causes one to miss its reality, but as far as seeking mysticism or a hidden reality (hidden by whatever underlying power, be it gods or billionaires, pick your poison) I find life much less stressful and more fulfilling with a healthy dose of skepticism.
That kind of statement begs for a story.
Just in case you want to try it out for yourself.
So even if there is no upper limit to the human lifespan, and mortality doesn't increase after 100, it would be very rare to see people older than 120.
Everlasting youth is going to be humanity's greatest accomplishment, and its biggest weakness.
Consensus created not by people with experience de facto. At least not the majority.
This just indicates a failure of imagination on the part of the author.
Suppose you are an immortal working on some long term goal, some plan that will take a few hundred years to complete. It is a complicated plan and you will need to keep it all in your mind, along with its history as it progresses, in order to guide it to success.
If you try to lead an active life throughout all this, perhaps your brain will acquire too much irrelevant information, interfering with your ability to carry out your plan.
So you sleep for decades at a time, just waking up long enough to check on the plan, learn about changes to the world since your lest check, and make adjustments. Then back to sleep.
The article is much less optimist than you seem to be interpreting it. It's basically "is there a hard cap on the age you'll die, or is it just random and independent of age past a certain point".
It says nothing about the aging process. Being older than 90 still sucks for the most part, and this article says nothing about quality of life.
It also is a very minor point, in a practical sense: is it impossible to live past 120, or is it possible with then odds of 1:10^9?
Even if we perfect the art of 3d printing new body parts and using gene-targetted cancer treatment, that may not make you spry, less forgetful, or less wrinkly