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Does the human lifespan have a limit? (nature.com)
94 points by feltsense on Feb 13, 2022 | hide | past | favorite | 221 comments



And hundreds of people reached the rarefied ranks of the supercentenarians — aged 110 or older — although demographers have validated the records of only a fraction of them.

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


The whole Blue Zones thing is pretty funny.

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.


Oh man, you wouldn't believe the flak I got for arguing that 90+ year olds wanting to see their family during COVID restrictions was actually a rational decision for them. They had a much higher annual risk of dying anyway than they did of catching and dying from COVID given the prevalence rates at the time and assuming standard family gathering sizes. I'm not even sure their risk was strictly greater given the affects of isolation on humans, but I can't make that argument numerically since the needed stats aren't quite there. But omg no one wanted me to argue for elderly autonomy.


Not all forms of death are necessarily equivalent. By all accounts, covid seems like a relatively long and painful one, slowly suffocating to death.


I think dying alone is much worse than dying with your family suffocating to death.


There are portions of the world where we don't have our older family members off living on their own.


I definitely meant in the context of the US where we throw away our elders once we have our own families. lol


at 90+, i really don't think its ethical to make someone suffer a miserable slow covid death against their will. The US has a weird relationship with people ending their lives on their own terms.


It's only rational if you ignore the secondary effects on others. It could increase community spread and ICU usage and thus increase the risk of death for others who didn't make that choice. The other likely causes of death (heart disease, cancer, and stroke) do not spread.


The people doing most community spreading weren't the 90 year olds.


Statistically, there are more people younger than 90 than older, so I don't dispute your statement, but I don't see your point. Is this to justify them breaking isolation?

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.


From my experience the 85+ year olds were mostly isolating at home, the 0-50 year olds out and about in schools, shops, restaurants etc. I'm not sure you needed regulations on the 85+ at all as most are not party animals and the risk of dying for them probably outweighs potential government fines.


Rural Greek Orthodox tend to have a lot of fasting days (IIRC about 200 in a year), and caloric restriction (CR) is a well known mechanism that slows down aging in many animals.

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.


Fasting is one thing. Living in a rural environment is another. In the old days Greeks didn't have cars (there weren't even any roads) so they had to walk - a lot. 20 kms a day maybe. The people of the Aegean island of Icaria are famous for their long lives, but in the past they would walk from one village to the next over mountainous terrain, where today there are tarmac roads and cars. This according to my grandmother's boyfriend who died in his late 90's. He was active until the end, never able to sit unoccupied after a lifteime of hard work- and he was sound enough of mind to teach me backgammon.

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.


Did you mean to reply to me or a different comment?


To you, but I was too short and I should have introduced my comment better.

Greek islands are one of the putative Blue zones, so this was the anchor of my comment.


My grandparents are now 95 and 96 (just shy of their 75th wedding anniversary). They are wonderful people, but it is clear that life is hard for them now. They have chronic pain and nothing can really be done about it. They have very limited opportunities for enjoyment or activity.

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.


My parents are like that in their 80s. They now respond to things like, "time is short, if there's anything you wanted to do, do it" with "that time has passed for us." It struck me as characteristic of their accidental lifelong stoicism.

It's sobering and makes it really hard to continue working in middle age.


I was surprised at the step down in quality at 59. Definitely worried about other lower qualities of life and thinking about how long it could last.

Yeah, I'd rather money be put into quality rather than quantity of life.


There's no reason you can't have both.


I have a gut feeling that as physical medicine has advanced faster than neuro or psychiatric medicine, people will live long enough to want to die, and euthanasia (self or pre arranged) will become acceptable, even normal.

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.


If you’re as good a parent as your comment suggests, I bet they’d trade the money for more time with you.


I would love for quality of life to improve so you could enjoy until, say 100, and then euthanize. The two problems i see are:

- 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.


That would be waste to remain healthy enough to live to 100, then kill yourself. Mental health is a part of living that long in the first place. Anybody who has the mentality that they'll just kill themselves once they reach that age, probably won't live that long anyway.


Dr. Sinclair's book Lifespan (https://www.amazon.com/Lifespan-Why-Age_and-Dont-Have/dp/150...) talks about extending the health span of people. I've been personally taking 1g/day of NMN for almost 3 years now, and I feel like aging has paused or is going backwards slowly.


I am willing to wager that Dr Sinclair is just peddling nonsense to make his million bucks and exit quickly.


considering he leads a research group at Harvard that publishes in high profile journals, you could actually look at the peer reviewed research, instead of relying on your "hunch"


It's old news but did you know, He did fuck GSK for 750 million? Basically no one could ever replicate his study. GSK should have done thier homework so boohoo for them but still all is not what it seems.

https://www.youtube.com/watch?v=JAFnD27ffqE


Well at least he isn't exiting quickly after having made his million bucks. I sometimes take NMN. I have no idea if it works or not.


How old are you?

How are you gauging “aging has paused or is going backwards slowly”?


Mid 30s. Gauging by how my joints feel and how quickly I recover from physical exercise and injuries.


I’m 38. I’ve beaten the hell out of my poor aging frame. And then fixed a lot of those injuries to my poor aging frame by not playing rugby any more.

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


He's also launched a podcast-- https://www.youtube.com/c/DavidSinclairPodcast/videos

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'm going to save you some money. What really works well and better than taking NMN orally(), eat a natural clean whole food diet (no pufa's or processed food), no alcohol or smoking and walk or do some sort of light exercise for about 30-60 minutes a day.

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.


but what if I do all of the above?


You would get healthy and waste money on NMN.


Where can you get NMN?


Don't bother. Sinclair is considered a quack by even some life-extension enthusiasts.

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.


I am doing some experiments with NR (no Sinclair in the business chain AFAIK) and pterostilbene and my ability to exercise has improved noticeably. I am 43 and I used to be fairly sore after a strenuous 60 minute exercise - especially my sinews were bad. This wasn't getting any better with more exercise, actually it was slowly getting worse with age, to the degree that I wasn't able to exercise in two consecutive days and sometimes I had to wait until the third day to go to the gym again. (To be clear, I am neither fat nor riddled with any serious disease.)

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.


I had a similar response doing a mostly vegan calorie restricted low protein diet. I was blown away because I had always been told protein = recovery, calories = recovery, but I have been able to rock climb pretty hard 6 days a week for the past 4 months now. Keto, general healthy eating, tons of supplements and all the other things I have tried have resulted in maybe 3-4 hard sessions a week and achy joints.


Note I am not disputing NAD supplementation, only the limits of what it can do and who can benefit from it.

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.


Why disregard someone simply because they own a piece of a company that also supports the goal? I think any rational person would do the same - you believe in something so you start, invest in, or advise a company.


I think the comment also said that this person’s views aren’t taken seriously in the aging research community. So the combination of their ideas and a desire to profit from them raises flags.


I don't think Harvard would let Sinclair have a lab with some 35 people and publish articles under their name if he was a total fraud/quack.

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.

[1] https://www.nature.com/articles/s41586-020-2975-4


Counterpoint from someone more educated (with a more precise conclusion that he is "not evidence based")

https://threadreaderapp.com/thread/1492902239312039938.html



There is no evidence it works taken orally. Save your money.


That's where my grandparents are right now. They retired in their early 60s, and they have a solid income between ss, pension, and 401k, but their healthcare takes up more-and-more of that money and they still struggle with their health. And just what have they done with their 30-odd years since they retired? They didn’t travel, pick up new hobbies, or finish their educations.

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.


"I want to work full-time until my late 70s, and die in my early-to-mid-80s at the latest."

We'll check back in a few decades...


An old guy driving a car very fast would be a sight to behold. Most have slow reflexes and vision problems.


My 70 year old father-in-law driving his Tesla s plaid would like a word


A lot of retired people I know have essentially taken on second careers as professional medical patients.


Lmao. So says the 20 something.


Eventually we will fix all these issues. The only deaths will be freak accidents or killings/suicides. Youth forever. We're less than a hundred years away from that kind of tech, I believe.


That is essentially a religious belief with no scientific basis.


It may be excessively optimistic, but it’s hardly unscientific or without foundation. There are animals whose biology does not age in the sense ours does, and we have done some incredible work increasing the healthy lifespan of lab rats/mice.


No, it's not. We are machines, we can be fixed. Just a matter of when, not if.


The laws of physics don't owe you a solution to any problem you wish to solve, including eternal life.

And even if the problem can be solved, evolution doesn't owe you sufficient intelligence for our species to solve it.


Any within the bounds of physical laws and resources available.


I remember my grandpa in the hospital after it was deemed surgery was unlikely to succeed and he decided to try to sit up which seemed to be quite difficult/painful and he says “well that’s the last time I sit up”. And he was correct.


There's an old quip that the greatest correlation for a country to have supercentenarians is them not issuing proper documentation at birth 120 years ago.

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.


> with life seldom being worth living after 90. I really wish we'd start investing in breaking this. I'll happen at some point

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.


Uh, I meant it the opposite way :) Unaliving yourself at 90 is a personal choice which I of course support, but I'm mostly talking about making sure we can live healthy lives over the current limit. The psychological issue is that even though we as individuals cling to life (sometimes too much), trying to rouse support for life extension sometimes feels like urinating in public.


whoops, I guess I misinterpreted what you meant by "breaking this".


There will be people who comes out to say we shouldn't do this because it means dictators will live longer or that old people will remains in power longer, as if old people are a blight on society.

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.


Change of generation is a thing that used to stump me. It's a valid problem, from older people having weird political choices to scientific research counting on fresh blood (yes it does).

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.


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.


No, no, I'm not talking about psychological baggage, but a very concrete biological mechanism. Take a look at this for a good description: https://scholars-stage.org/public-intellectuals-have-short-s...


Do you think psychological bagged is not real and not ultimately rooted in some physical mechanism (s)?


They'd still leave the problems to the next generation. The next generation just wouldn't be in charge.


This is something we've basically already witnessed with how society is operating right now.

The people inheriting the problems we started making 40 years ago before they were born even, still have very little say.


Yes, and if people are able to live forever I don't think that would be a change for the better. The 'haves' would at some point become aware that the 'have nots' have the potential to threaten them if they manage to live just as long, and I'm pretty sure I know how that would end.


I don’t think the point of living beyond 100 years old is the years that come after you are 90 (pretty bad years), but that one has more “nice” years to live. Example:

- 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!


I beg to differ. In my opinion, life doesn’t really start until you’re 25 or so, maybe even 30. The first 18 years are generally spent at home, following other peoples rules, and learning how to get by. The next few years you get your independence and start finding your place in the world. If you went to college, then you enter the workforce and are probably getting by, still finding your footing.

Then the real fun starts.

I just turned 40, and feel like I’m finally hitting my stride.


A significant percentage of kids are also hampered in their development while growing up by abuse, miseducation or neglect, so they may need even more time to recover from this and 'find their footing'. Many 25 year olds are still processing childhood trauma and playing catch up with their less disadvantaged peers.


This is a great viewpoint emotionally, but physically you can’t do at 50 what you could do at 25. There’s a reason pretty much every sport (even golf!) has a “masters” class for older players.


This is incorrect or at least incorrectly stated with respect to the word "you". I didn't start running regularly until my late 40's and I loathed nearly every step for the first year but my fitness and enjoyment levels slowly improved especially after discovering trail running. I started participating in ultra trail races after a couple years and found a wonderful community of people enjoying an activity all around me I didn't even know existed. Now, 10 years later, I'm the fittest I've ever been and far more fit than the vast majority of 25 year olds.

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.


If you had followed the exact same fitness regimen when you were 25, you would have seen better results: higher speeds, more endurance, shorter recovery times, etc.

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.


Speed and recovery? 100%. Endurance, not so much.

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.


Obviously had I started from an earlier point, I may have achieved a higher overall peak performance level but that isn't the point I was addressing. Nothing reverses entropy that we know of but that isn't the point either. The point is that saying "you can’t do at 50 what you could do at 25" is patently wrong. I point this out simply because many people have an incorrect perception of their ability to alter their fitness via lifestyle changes.


I’m in my 50’s and I’m a much better golfer than I was in my 20’s. Partly club technology has enabled me to hit the ball more consistently and partly I now don’t try and hit the cover off the ball each shot :)


I don't think the post is talking about golf. If you look at physically demanding sports, most players don't last past 40 unless they're an incredible athlete.


This only applies to professional athletes. Plenty of older people play sports as talented enthusiasts.


I actually see that as the other way. If humanity's best athletes and most incredibly gifted people physically can't make it, who can?


I retired shortly after my fortieth birthday, and it's been a godsend!

My worst day of retirement was better than my best day of working or education.


That's quite an assumption. Plenty of examples exist of people with decay starting later than average that eventually went through a short "off-ramp" earlier, plenty of examples of people who experienced significant decay very early but then dragged it out very long, seeing their "still seemed so young ten years ago!" peers disappear one by one.


Please explain to me and try to convince me why we should. I’m serious, I just can’t understand why extending our individual lifespan should be a goal of our age, instead of focusing on making our life much better when it’s more worth living.


They go hand in hand. In most professions you need to be about 40 to be competent. When you're young this doesn't seem likely because you don't see many competent middle aged people: that's because they're up in management actually running things. Unfortunately we start aging mentally around the same age, and at 60 we're not really capable of creative work anymore.

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.


Suppose, right now, normal life expectancy was 200 years. How would you feel about a new program being rolled out to impose disease and death on everyone over 80?


This seems fallacious to me, the scenario you describe has zero opportunity cost for being alive till 200, it's free. Assuming no afterlife, you gain nothing by artificially limiting your lifespan to less than half its amount.

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).


If opportunity cost means anything at all, “not extending one’s life” must have a truly dizzying opportunity cost.


Good argument, in the spirit of the reversal test https://en.m.wikipedia.org/wiki/Reversal_test


> Alfred Nordmann argues that the reversal test merely erects a straw-man argument in favour of enhancement.

Yes, basically as a fellow commenter argues. Thank you for the link.


16 billion people stacked on earth?It's a pointless hypothetical because violence would have prevented that scenario long before. And what grand violence it would be! So much easier sending great-great-grandsons into battle than sons and grandsons.


It seems much easier and more feasible than inventing an FTL space drive. If you could live to be 10,000 or 100,000 years or more you could visit interesting places.


It can, and should, be both.


If you haven't experienced it yet, I highly recommend you check out 17776: What Football Will Look Like in the Future [0]. It explores what happens if humans stop aging/dying/being born, narrated by a few cheeky, sentient space probes.

[0] https://www.sbnation.com/a/17776-football


I love this series, and most stuff by Jon Bois.


so good. thank you for reminding me this exists


In a Wondrium lecture on genetics and evolution, this question was also discussed. A compelling (but unproven) explanation for our “age limit” is that any genetic trait that improves your chances before reproduction at the cost of your chances after reproduction (and raising your offspring) will benefit your genes and thus will “win” in the long run. If this is an important effect, it will be very hard to defeat.


It's pretty intuitive to also consider limits on lifespan as a function of conserving resources on a family or tribal level. At a certain point, the utility a population could gain from labor or knowledge of older members is outweighed by the burden of taking care of them and providing for them.


Yes but from what i recall, evolution doesn't work like that at the level of population.


That is a good point that it is not like many other factors that affect evolution. I think there could be an evolutionary impact if the high cost of resources for one tribe, in tribe versus tribe competition, or a family, in family versus family competition, put the tribe or family at a disadvantage.


I doubt longevity was an evolutionary force way back.


I remember reading a book (Protector, by Larry Niven[0]), in which the protagonist (a "proto-Belter"), eats a sweet potato, turns into an ugly-ass duck, and lives forever.

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]

[0] https://en.wikipedia.org/wiki/Protector_(novel)


I’ve read Protector many times over the years, and this summary misses only one thing: he’s a superstrong duck.


It also misses that it's not an _ordinary_ sweet potato.


If I remember correctly, it also needs thallium to grow. So the plant doesn’t grow on earth.


<puts down fork>


If we consider the average lifespan as say 80 years old, I find it quite interesting that no single human ever has achieved even close to twice that age.


>> find it quite interesting that no single human ever has achieved even close to [160 years].

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.


If we consider the average height as say 160 cm tall, I find it quite interesting that no single human has achieved even close to twice that height.


Well that is interesting too. The same does not appply to weight. But for some reason I find the age distribution more curious.


1ft off is pretty close in my books


Well, we already have a lot of medical interventions that skew our species' "normal", pre-civilizational population tree towards something never seen in nature.

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.


Didn't most people live to their 60s if they survived childhood and pregnancies?


The bones from old burial sites up to and including the Middle Ages indicate that most people didn't live into their 60s. Not even those who reached 30 in good health.

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


The child (<5 years) mortality rate in the US in 1800 was 46.29%. I can't seem to readily find US life expectancy at birth for 1800, but most places seems to have been 30-35, which would correspond to life expectancy at 6 years of age of at least 51-60.

Life expectancy at birth was around 30-35 for at least the several preceding centuries in Europe.


This is a nice graph from the Modern Age (mid-1500s to late 1900s) in England.

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.


This is a very fascinating chart! It seems that over the five centuries the healthspan (probability of survival within the lifespan) increased drastically but the lifespan itself is more or less fixed at 90-100 years. The healthy plateau is much longer now but the following drop is much faster.


Yeah it depends whether you count all of the infant deaths in the average.


Why?


I think the GP just means that the tail of the age bell curve seems (surprisingly) short to them.

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.


We've done a lot to shift this away from a normalized curve, which feels very unfair to us as humans, to one where more people have a chance to live to a longer age. We've spent much less effort trying to extend the longest lifespans. This seems totally rational to me.


It seems strange for some people because they imagine this "average" as a classical mean and the intuitive shape of the bell curve - the biggest chunk must be in the middle ("for every child that dies at birth someone must live to be 160 to have the 80 years average where most people should be") rather than a statistical life expectancy. We substantially reduced a lot of the external factors killing us early (disease, war, accidents, etc.) and we're hitting the real limit of human lifespan. We haven't addressed this because we don't have the tools yet. So all the work was to push the curve to the right because that benefits most people and it has a lower threshold to achieve this, without actually pushing the tail end further right because it benefits very few and it seems like an impossible task today.

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.


Extending life is a fantasy of the middle-aged who are still feeling great and imagine it forever.

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...


We've only had organ transplants for 60 years. I'd like to know how far we could push it in a world where we have a donor organ pool grown to order and a preventative approach to organ replacement.

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.


Keep in mind that transplanted organ recipients must take immunosuppresants for life and that transplanted orgrans eventually fail, usually within a decade or so. Being on immunosuppressants means even a common cold can kill you without medical care. This is probably more of a limiting factor for long-term survival by continuous transplants than the availability of donors.


The next big step in organ transplantation will be custom grown personalized organs which don't trigger an immune response, and thus don't require immunosuppressants. This might be available in a limited form for some organs in our lifetimes.

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.


Yup, best to die young to avoid these issues!


This is just a waiting game to resolve.

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.


Whenever this topic comes up, I’m always reminded of the fact that the bible knew of this long before any statistician.

'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.


Funny, because there are many bible characters older than 120 years. One of many contradictions, https://www.youtube.com/watch?v=RB3g6mXLEKk


The Bible is a loose collection of different books written by different authors over a period of thousands of years. We shouldn’t be surprised that some of them say different things.


[flagged]


Neither commenter was advocating for having it both ways. I don't even find them at odds with one another. I happen to agree with both assertions.

OP: "millenia old book makes claim about life that is empirically uncontroverted in 2022" – i agree

Parent: "the bible is a collection of stories and contradictions should be expected" – i also agree

The first half of your comment could indeed be relevant in the right discussion, but this thread was not it. The rest then falls terribly flat and comes off needlessly aggressive and snide.

> Christians are easily confused

I would be embarrassed writing such things in a public forum.


[flagged]


Nobody in this subthread even claimed to be Christian, so I don’t know what your point is.


Are you serious? You’ve left behind petty stereotyping and are boldly venturing into bigotry here.


Save your incredulity. There is no shame in judging a fool. Bigotry is based on prejudice. That is to say strongly held beliefs not based on reason or evidence. Does that sound familiar to you?


Check out the book of Genesis. There is a specific point at which God changes the maximum human lifespan to 120 years, after which this does not occur.


So this is the definitive proof that Jeanne Calment is a fake!


The Bible is many different books combined. Some contain practical advice for living, others have philosophical rules of thumb, allegories, etc.


An alternative interpretation is that 120 years is the period of reprieve before the Flood.


Antediluvian lifespans were order of magnitude greater. Methuselah was, I think, over 900 years. After the flood the lifespans became significantly shorter.


or maybe they used lunar calendar, 900 years are actually months...


Then you have people becoming daddies at the ripe old age of ... 5.


Didn't this actually happen somewhere in Peru in between two worlds wars?


> As a non Christian this always baffles me.

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.


How many 120 year olds do you think the average person would be exposed to several thousand years ago? Especially in an age where birth certificates did not exist.

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.


Personally, probably not very many. But traditions of information sharing and story telling between humans have been strong long before the internet. This isn't some obscure information about space or DNA or something. This is something that would have been relatively accessible without technology.


How many numbers are in the Bible, and how many of them are wrong (which we conveniently gloss over). The world was made in 6 days?


My favorite is of Pi being 3.0:

  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.
Although in fairness, 1) if you round both the diameter and the circumference to the nearest cubit, it can just about work (the numbers are rather narrowly constrained to 9.66 and 30.34 cubits), 2) the nearest multiple of 5 or 10 cubits might have been considered sufficiently precise for a rough description, and 3) the bowl was "a handbreadth" thick, and if we assume that they measured "brim-to-brim" on the inside and "compass it round about" on the outside, and that a cubit is 18 inches and a handbreadth 4, Pi comes out almost exactly right.


Asimov had a possible explanation for 6 days: http://www.sumware.com/creation.html


Good read - thanks for sharing


why assume that they meant earth days?

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?


>if they're creating earth, then how could it be that they're using earth days? (allegedely, earth is just getting created)

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.


logically plausible and "scientific" and/or "realistic" are different things.

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?


I'm not claiming that ancient people were dumber, I'm claiming the cultural and spiritual purpose of a creation myth isn't served by realism or logical consistency. God creating day and night before creating the sun and moon is par for the course for these stories. The Babylonian myth some people believe Genesis is based on - the Enuma Elish, says the god Marduk killed his nemesis Tiamat, cut him in half and made the sky out of one half and the Earth out of the other.

>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.


Any attempt to be logically consistent runs into issues. If you assume the first six days where the equivalent of geologic time then so was the 7th. Thus God would still be resting and not doing anything else biblical in the rest of the good book. Give up on consistency and that problem goes away.

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.


If the bible was written by humans before humans knew about carbon dating and evolution I would assume humans meant 6 days. I mean, why wouldn't they believe it was 6 days? That was just as plausible as anything else.

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.


It’s all fiction and fantastical accounts of history anyway, I wouldn’t read too much into any of it.


Maybe that 6 days is a metaphor.

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.


You hit on the 'specifics' of religion that I've always found funny in humantiy. Why does it matter to most people if it is 6 days or 15 billion years? How does that change anything in actuality?

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.


I think that reality is largely a story-based thing for many of us. There are as many stories as there are authorities. Science offers a story. So do the various religions. So do various other cultures.

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.


> Maybe that 6 days is a metaphor.

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?


Well, yes.

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.


Hah. I wonder what of experts you have in mind


> Maybe that 6 days is a metaphor.

right, so if a biblical number is wrong we find some reason to excuse it.


If it's a metaphor then it might not be wrong.


Current scientific models lack a robust cause of origin of life. We don't know the beginning. If we do know the origin, how likely would it change our estimations of age of things? You have to realize that these numbers are linear extrapolations(educated guesses) and more importantly, they are not tested like vaccines or medicines(neither can be tested).


current scientific models are far more robust than "In the beginning, God made the Heavens and the Earth."


My recommendation to you would be to not read ancient sources. Secular sources are not any more rigorous.


Consider another translation: “And the LORD said, My spirit shall not always strive with man, for that he also is flesh: yet his days shall be an hundred and twenty years.” (Genesis 6:3, KJV).

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.


Doesn't the Bible also state that Enoch and Elijah never died?

If you're a Christian, doesn't this mean that you believe that they are both still alive and are world's oldest humans


Yes, and Moses as well who was resurrected. But they are in heaven where the Tree of Life is. We cannot live forever without eating from that tree (see Gen. 3:22-24).


Then go read Psalms 90:10 and realize the bible has contradictions.

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.


Gilgamesh did it first.

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.


Gilgamesh did it first.

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.


Where as to me, not pursuing it is condemning people to countless years of not existing. Which seems far more cruel than choosing to have a limited life span.

What is the difference between not investing in life extension research and just putting a pillow over the face of a million people?


Because it's the default nobody is morally implicated in electing to avoid it. There is no smothering.

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.


>Because it's the default nobody is morally implicated in electing to avoid it. There is no smothering.

The trolley problem would like a word.

https://en.m.wikipedia.org/wiki/Trolley_problem


You're effectively switching the track to "Strangulate the whole planet with humans and their downstream effects!", very cool, or y'know any other disasterous permutation. We've already got population issues if that isn't compelling enough for you.


Because an immortal human won't change their thinking re long term impacts on the planet. Sure buddy.

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?


You're allowed to impute whatever you may wish. My aims are the maintenance of the single rock in the known universe capable and currently sustaining life, and intelligent life at that.


Environmental impact is not even on the same axis as longevity.

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.


The verse you quoted doesn't say our maximum age is 120, it literally say we live to 120.

It must have been obviously inaccurate even when it was written.


So if we get a single human who, without dispute as the oldest woman has some controversy as to the validity of her age, lives past the age of 120 will that be proof the bible is untrue and all it’s writings are false? Because I have a funny feeling now that people are much more documented we will pass the 120 year mark any time.


> So if we get a single human who, without dispute as the oldest woman has some controversy as to the validity of her age, lives past the age of 120 will that be proof the bible is untrue and all it’s writings are false?

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.


Goalposts, if you want to know what they will move to:

“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.


Most of those are valid responses in textual criticism.

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.


Not really. Because it wasn't a hard limit. Even after the Bible records that God said this, it records people living to 450, 175, 120 years and so on. After God said, the span gradually reduced to well below 120. So, a case could be made that it wasn't a hard limit.


Well, the chapter prior to that one describes humans living for hundreds of years, so I don't think someone living past 120 will really introduce any more theological problems.


Figure this: If I come up with a theory that people can grow older than 120 years because of a golden teacup whizzing about somewhere in the Oort cloud, and we find a person older than 120 years, does that mean the golden teacup exists?


You've convinced me. Where can I learn more about this golden teacup of eternal youth? Does it answer prayers maybe?


No one would care. We already have a 122 year old, no one's tossing their bible out over it. Conflicts in religious texts are common and always resolved one way or the other.


Perhaps it will just mean we are drifting further from god.


Many of the numbers in the Bible are not literal. Partly due to translation and cultural meanings of various phrases.


Bible fans should really study up on how Noah lived 950 years. Maybe ark building is good for health?


That’s an incredible verse: we underestimate the wisdom of the ancients sometimes.


On the contrary, it's incredibly common for people to want to believe that the ancients were somehow better or wiser than we are, or marvel over supposedly impossible feats (see: pyramids, Greek fire, occasionally semi-correct guesses about the nature of the universe).

They were just people like us; right sometimes, wrong much more often, but in their case, lacking the tools to verify most ideas.


This is downvoted but it's also true. It's really impressive what they were able to build and figure out with the tools available too them. (This isn't a great example, but let's put that aside.)

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.


lucky guess i'd say


In Hinduism the age a person lives to changes in each Yuga or cycle before it all starts again

https://en.m.wikipedia.org/wiki/Yuga_Cycle


Doesn't DNA have a halflife of like 512 years? I imagine if every cell in the body affected by that there isn't a way to prevent it all from destabilizing by that point.


Presumably that doesn't apply if your cells are continuously reproducing creating new copies of DNA. In some sense your DNA comes from your parents and extending back through those lineages has lasted vastly longer than 512 years.


Wow that's actually quite insightful. There are theories on cell death after some generations, dna damage etc. But I'm not sure how they explain the refresh during birth/zygote formation.

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.


There are clonal trees that have lived much longer than 512 years too with the same DNA.

https://en.wikipedia.org/wiki/List_of_oldest_trees


Trees in general live longer probably because of their tougher cell walls? Or may be their error correction mechanisms happen during cell division? (just guessing)


No, cells have active DNA repair mechanisms working all the time. They also have transcription ECC that attempts to detect and/or correct transcription errors. Some critical protein coding sequences are arranged to make some errors harmless, or are duplicated, etc.

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.


> But I'm not sure how they explain the refresh during birth/zygote formation.

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.


I think it was in Lynn Margulis' book What is Life that I read that sexual reproduction occurs more where there are more parasites, which gives strength to the idea that sex is error correction.


DNA is continually regenerated.


Doesn't that mechanism degenerate in seemingly an innumerable number of ways



If you believe in many-worlds, then some future yous will probably live indefinitely long and be the really weird outlier in their respective worlds.


The half-life of a DNA strand is purportedly to be about 542 years.

So, it’s probably like 250 years with intensive DNA repair effort.


Aren't cells constantly being replaced, including their DNA?


Cells are self-replacing under the control of their own DNA; not pumped out of a factory. Slowly accumulating errors in the DNA can compromise the ability of cells to make good copies of themselves, potentially leading to cancer calls instead.


Maybe intermittent fasting autophagy can be the key to elongating life through that continual repair.


Right, that makes sense, but that's not really relevant to what I assume is the half life of a specific strand of DNA, right?


Half-life of 542 assumes to mean without an active mitochondria engine to keep its strand largely intact.

Error rate during active lifespan is real. Gamma ray probably is the largest contributor of active (or even inactive) DNA being disturbed.


Doctors think, but are not sure, that a human can live to 106. 106 is the absolute limit.




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