21 ms·
Your Body Wasn’t Built To Last: A Lesson From Human Mortality Rates (2012)
- icebraining 11y ago"Ignoring, of course, the upward shift in the lifetime distribution that will result from future medical advances."
- zkhalique 11y agoThank you. Yes, that makes a lot of assumptions. Let's also not forget future dietary advances.
- hughes 11y agoHave we made even a single advancement that can increase the age to which humans are capable of living? We've made lots of progress on stuff that kills us early, but I can't think of anything that makes our bodies actually last longer.
- Retra 11y agoThe distinction you are making is a bit artificial.
- ars 11y agoNot really. At a certain age people die of "nothing", they just die, without any specific reason. It's not the same as curing something that kills people early.
- kbenson 11y agoI was under the impression that wasn't the case, there's always something, or more accurately, many somethings working together that cause degradation of the system to the point of failure. Are you saying at some point some major organ like the heart just decides to stop beating?
- JoshTriplett 11y agoIt's not that there isn't a cause. But at some point, humans start dying of multiple systemic failures, and whatever proximate cause happens to lead to death, the root cause is aging.
- kbenson 11y agoSo, similarly to AIDS, the proximate cause is a specific problem, the root cause is AIDS and a reduced immunodeficiency system. The question is, do we treat aging as this unavoidable and untreatable condition that will kill us, or do we treat it as a condition to be managed or cured like anything else?
- JoshTriplett 11y ago> The question is, do we treat aging as this unavoidable and untreatable condition that will kill us, or do we treat it as a condition to be managed or cured like anything else? Exactly. We need to do the latter, rather than just treating the symptoms. Aging is not untreatable, it's just hard. But it's by far the most worthwhile, because fixing it would fix so many other problems at once.
- smeyer 11y agoPeople don't die of "nothing". When it's said that someone dies of old age, there's still some actual medical cause (although no one is demanding an autopsy to find it when an 85 year old dies peacefully in their sleep).
- deleted 11y ago[deleted]
- morcheeba 11y agoPeople don't just die of "nothing" ... it's just that the death is natural and we don't bother investigating. But, usually, it's one of these that kills old people: http://seniorhealth.about.com/od/deathanddying/tp/cause_death.htm http://seniorhealth.about.com/od/deathanddying/tp/cause_deat...
- rfrey 11y agoIt's not artificial at all. Lifespan is a distribution, what OP describes is moving the distribution around a bit without moving the bounds.
- kbenson 11y agoWhat if there are no upper bounds, and all there is to work with is the distribution?
- ska 11y agoDo we have any evidence for that view? There is at least some evidence for the converse.
- kbenson 11y agoWhat evidence is that? What single thing is absolutely sure to kill us by age X? Specifically, I don't think "aging", which is really a root cause of other things which cause us to die counts. If the problems aging causes could be reversed or cured, then aging no longer would cause death.
- ska 11y agoTelomere shortening would be one example which, if there is no mitigation possible (and we don't have one or know that one is possible) is a pretty hard limit. That's why I said "some evidence" not "strong evidence", we haven't proven that there is an unavoidable hard limit, but a) we have no evidence that there isn't and b) we know of several mechanisms that look like they may be hard limits.
- kbenson 11y agoI'm aware of telomere shortening, but my understanding is that the theory is not as widely accepted as you imply. I could be wrong though, so feel free to support that,I'm open to new information. That said, it's a limit we may need to overcome at some point if we wish to prolong our lives past a certain point. It's a good candidate for an upper bound on life expectancy, but we still aren't even sure it works as we think. I think that's a good reason why we haven't directly worked on increasing the bounds of life expectancy, we are still definitively identifying them. Note: I may have come across a bit sharply in my prior comment, but my intent was literally to just ask for the evidence you were referring to and supply criteria I thought needed to apply.
- pavel_lishin 11y agoArtificial hearts is the most obvious example.
- JoshTriplett 11y agoNot really, though it's more in the direction we'd need. At around 120, humans seem to die of "systemic failure of the everything". Replacing one part won't suffice; to live past about 120, you either need to replace biology completely, or repair some of its fundamental systemic mechanisms.
- pavel_lishin 11y agoI guess you're right in the sense of "some people live to 100 without artificial hearts", but that sort of focuses on outliers. Many people died of heart attacks as they aged.
- Nagyman 11y agoYou mean advancements as in in practice on humans? There certainly seems to be research and progress in areas that affect lifespans (neurdegeneration). https://en.wikipedia.org/wiki/Calico_(company) https://en.wikipedia.org/wiki/Calico_(company)
- tired_man 11y agoYou can have all the organ replacement you want. Once your drive train (feet/ankles/knees/hips, which ultimately impact on your spine) is shot, all you're gonna want to do is lie in bed.
- pavel_lishin 11y agoI'm instantly reminded of Lucas Garner, a character in Larry Niven's novels. His spine has atrophied due to advanced age, but he still gets around quite well in a wheelchair. I think a lot of actual real-life wheelchair-bound humans would object to your presumption of what they want to do.
- tired_man 11y agoIf they're up for the pain, they have my support. I presumed nothing. Have you ever experienced sciatica or back pain from herniated discs so intense you piss yourself? When even breathing hurts? If you are able to zing happily along in your Rascal Scooter and ignore the pain, my hat is off to you.
- Symmetry 11y agoGiven things like hip replacements and anti-inflammatory drugs it might be that we're better at keeping people mobile in advanced old age then we are at keeping them alive.
- tired_man 11y agoReport back when you have first hand experience with that hip. I think you'll be unpleasantly surprised. There's a lot of chicken counting going on when the future is discussed. We have very effective pain medicines right now that many people can't have because of their potential for abuse. I wouldn't count on anything until you see actual meds on the market that some group of "We Know What's Best For You" people hasn't declared evil.
- tired_man 11y agoDid you catch this: http://www.sciencedaily.com/releases/2015/08/150831001112.htm http://www.sciencedaily.com/releases/2015/08/150831001112.ht...
- crusso 11y agoThat doesn't make sense unless you have knowledge of what our specific maximum age should be. "Last longer" is a fairly equivalent way of saying "wasn't killed early".
- reasonattlm 11y agohttp://dx.doi.org/10.1186/1478-7954-8-18 http://dx.doi.org/10.1186/1478-7954-8-18 Background The ongoing increase in life expectancy in developed countries is associated with changes in the shape of the survival curve. These changes can be characterized by two main, distinct components: (i) the decline in premature mortality, i.e., the concentration of deaths around some high value of the mean age at death, also termed rectangularization of the survival curve; and (ii) the increase of this mean age at death, i.e., longevity, which directly reflects the reduction of mortality at advanced ages. Several recent observations suggest that both mechanisms are simultaneously taking place. Methods We propose a set of indicators aiming to quantify, disentangle, and compare the respective contribution of rectangularization and longevity increase to the secular increase of life expectancy. These indicators, based on a nonparametric approach, are easy to implement. Results We illustrate the method with the evolution of the Swiss mortality data between 1876 and 2006. Using our approach, we are able to say that the increase in longevity and rectangularization explain each about 50% of the secular increase of life expectancy.
- clamprecht 11y agoBut if you multiply that 0.000001% by 7 billion people, what do you get?
- mikeash 11y agoThe wording of "no human" implies that the total population is already accounted for.
- richmarr 11y agoI agree, the article's assumptions are lined up to stretch to an attention grabbing headline, but... "99.999999% certainty that no human will ever live to the age of 130" is not the same as "99.999999% chance of an individual reaching 130". Sorry, just my statistics pedantry for the day.
- isp 11y agoIt's definitely not the same: I think you're missing a "not" in "99.999999% chance of an individual reaching 130". :-)
- hueving 11y agoYou're mixing up confidence vs probability.
- schoen 11y agoIt's not phrased as a "probability that an individual human will live to 130", but as a "probability that any human will live to 130" (although I'm not sure whether that's the calculation that the original author intended to do or whether it was correct). ... but I think it was (if you assume the unlimited validity of that law as ages increase, and its validity to everyone in the population), because I tried to use that formula and my bc crashed (!), the first time I've ever seen that. It was trying to compute e to the power of -1196855871164164755229127183619028619603176.29243358214210581124 which was the probability of a particular individual surviving to 130 according to the formula. That is a super-small number, which dwarfs the human population of 7 billion, so probably the original author did mean to say the thing about anyone-ever, and was probably correct within these assumptions about exponentials and their applicability.
- maaku 11y agoAlso ignoring animals that do have indefinite natural lifespans...
- pixl97 11y agoEh, might as well compare apples and oranges and expect it to describe a banana. Most animals that live well over 100 years have a very low metabolism. For example turtles and tortoises. Other living organisms that have biological immortality are generally simple creatures. As in all the components of the creature can be replaced and the creature doesn't change in function. Fish, for example can live hundreds of years, but their biology is considerably different than a mammals. That said, whales and alligators can have extremely long lives. It may be that water acts as sunblock and reduces the amount of UV damage allowing life to continue much longer than most land animals.
- maaku 11y agoRight, but it puts a lie to many of the theories that involve mortality being an inevitable result of biological chemistry -- e.g. that cells can only divide so many times before they MUST die. The reality is that for just about every aging related failure mode, there is an example of some animal somewhere that is able to fix or otherwise defend against that very form of damage, a proof by example that such damage is not inevitable or irreversible.
- murbard2 11y agoThat title is literally the dumbest sentence in the entire article, which is an outlier in an otherwise interesting piece.
- sctb 11y agoWe reverted the submission title from “99.999999% certainty that no human will ever live to the age of 130” to the article's.
- thomasfoster96 11y agoIn other words, John Citizen statistically won't live to age 130. Someone who is better off health wise and is less of a risk taker than the average American - I bet given a lifetime of modern day medicine or better, you've got a great shot at 130.
- pixl97 11y agoThe key is 'or better'. And no, even with the best modern (as in today) medicine you have no chance of 130. The convergence of accruing damage along with DNA that is not optimized for such long life puts a lot of pressure on the older body. It is very likely that the solution to the age 'problem' will occur at a much younger age with genetic manipulation to avoid or prolong the issues that occur at old age. The question then becomes, if you manipulate your DNA, are you human, or a human subspecies?
- JoshTriplett 11y ago> The question then becomes, if you manipulate your DNA, are you human, or a human subspecies? That doesn't seem like a particularly interesting question. It wouldn't change the conclusion that humans can't naturally live past 120. And that conclusion itself becomes unimportant if we can reliably work around it.
- thomasfoster96 11y ago> even with the best modern (as in today) medicine you have no chance of 130. We don't know that. Nobody has lived an entire life with modern medicine. So many things such as organ transplants, vaccines, antibiotics, discouragement of smoking, awareness of carcinogens, etc, have been developed since many of the people aged 100 or above were born, or in many cases, were middle aged. > The question then becomes, if you manipulate your DNA, are you human, or a human subspecies? That's mostly irrelevant - there is plenty of longevity-related DNA variance within Homo sapiens as it is.
- colin_mccabe 11y agoI'm sorry, but that conclusion is not supported by the article (or by other data). No human being has a "great shot at 130" no matter how modern the medical care is. The longest documented human lifespan is 122 years. Living past 110 years puts you in a VERY exclusive list: https://en.wikipedia.org/wiki/List_of_oldest_living_people https://en.wikipedia.org/wiki/List_of_oldest_living_people Why this is true is one of the great medical mysteries of our times, which we haven't solved yet.
- quinndupont 11y agoAhh, yes, the fallacy of using history to predict the future, with math. This is a fun kind of math problem, but it completely ignores a huge wildcard, namely, human ingenuity and technology. These kinds of predictions have been toppled many times before simply because they aren't about reality (biological or physical properties), rather they are just calculations about ethereal things. Sometimes mathematics maps on to the physical world in startling good ways (the "unreasonable effectiveness of mathematics"), but biology isn't physics, and human life span is as much social and technological as it is biological. Of course, history is probably our best tool to make such estimations (we don't have any better guides)... until it isn't (that day some new wonder drug is invented, or some new artificial body, etc)
- andrewstuart2 11y ago> The fallacy of using history to predict the future, with math. You say that as if we have anything aside from the past that we can use to make predictions.
- cookingrobot 11y agoYou can look at the mechanics of the thing you're studying and make predictions based on what's possible. Like if you were watching the development of the space program you could make a prediction about when we'd get to the moon, without just looking at the historical top speed of airplanes we'd built before.
- murbard2 11y agoYes but that's still using the past. All we have to work with, in order to formulate scientific theories, are correlations and patterns detected at some point in the past. Of course, some correlations and patterns are much stronger than others, and we can be more confident in the predictions they yield. So really the fallacy is about using too weak a model to predict the future.
- quinndupont 11y agoYeah, we don't really (other than, perhaps, physical experiments as cookingrobot's reply suggests). I think such investigations are fun, but also presuppose a very misguided concept of the human and sociality.
- jpstory 11y ago"So...you're saying theres a chance!"
- powertower 11y agoI'm 99.999999% certain I would not want to live that long.
- EC1 11y agoReally? All I can think about is how to not die. The thought terrifies me. It got to a point where it's my main motivator in what I do. I used to be lazy and play video games all day and when I realized how finite and easy destructible our lives are, I get crazy scared and work like crazy so I don't waste my time. There's so much I want to learn and do. The only problem is the limit of time. Death is incredibly terrifying. I don't understand it and I don't want to, I just want to live. Forever preferably.
- noir_lord 11y agoIt's strange how different people's attitude to death are, I don't fear it at all, I'm going to enjoy life for as long as I can then check out in the least painful way possible. Maybe it comes from been atheist (I'd find proof of life after death a lot more scary), the universe was around 14 odd billion years before I was and it'll be around long after I'm gone.
- DarkTree 11y agoYeah I have a similar attitude as you. Death itself does not really scare me. I often use the analogy, "It is like before you were born". It just doesn't exist or concern you after you die. What does scare me a bit is the idea of aging, losing physical ability, and mental faculties. I am afraid that once I am old I will always looking back at "better times" with nothing but death waiting for me in the future. I'm 23 now, so it is inevitable that my mindset will change. Also, aging happens slowly. You don't just wake up and realize you have no physical ability anymore. Thankfully.
- noir_lord 11y agoI was diagnosed with a serious condition this year, the prognosis is very mixed (luck of the draw) so the idea of losing physical ability became very real very quickly. The annoying thing is that prior to that at 34 I was physically better than I'd been in my entire life (even when I was a gym rat) so having to give up many of the physical activities I really love was a shock. Even that doesn't scare me as much as losing my mental agility though, that worries me, the medication I'm taking has a marked effect on cognitive function.
- matheweis 11y agoAll religious aspects aside, it's amazing that this was documented back to at least 2nd century BCE to within 2.5 years or so. "... they are mortal; their days will be a hundred and twenty years." https://www.biblegateway.com/verse/en/Genesis%206%3A3 https://www.biblegateway.com/verse/en/Genesis%206%3A3 ... with the longest living person in modern times documented as being 122 yrs, 164 days: https://en.wikipedia.org/wiki/Jeanne_Calment https://en.wikipedia.org/wiki/Jeanne_Calment
- javajosh 11y agoDoes living 2 years and 164 days over the deadline (so to speak) count as a sin?
- krapp 11y agoKnowing the Old Testament, probably. You live until God kills you, but it's still a sin to live too long.
- Nadya 11y agoThe Bible isn't a good prediction of age. Seth lives to be 912 years of age. (Gensis 5:8 ) Enosh lived to be 905 years of age. (Gensis 5:11) Reu had a son at 32 then lived another 207 years living to be 239 years of age. (Gensis 11:20-21) Abraham lived to be 175 years of age (Gensis 25:7) Also the passage you noted, Gensis 6:3, is often seen as referring to the amount of time from when God determined to destroy mankind to when God sent a global flood and not the lifetime of humans mandated by God.
- pugio 11y agoActually, the Jewish tradition is that Moses lived 120 years, and that, after him, 120 years was the approximate cap on human life. Many Jewish well-wishings end with something like "may you live until one hundred and twenty".
- nicholas73 11y agoIn middle school (Christian) our religious studies teacher told us that ancient Jews used "40 years" as an expression of a generally very long time period. So 120 years might be an extension of it, not an actual prediction. I did always find it interesting that it happens to be about right though. But of course it's easy to just record who lived to be the oldest.
- jancona 11y agoRelated: http://slatestarcodex.com/2015/08/20/on-overconfidence/ http://slatestarcodex.com/2015/08/20/on-overconfidence/
- alejohausner 11y agoThe article addresses Gompertz' law: the probability of dying in any given year increases exponentially with age (older people have ever higher death rates). This is an EMPIRICAL FACT. As you live longer, this probability accumulates exponentially, so the probability of being alive falls super-exponentially: p(being alive) = aexp(-exp(bt)). I'm pretty sure there ain't nothing you can do about this. Why not? Because evolution built it pretty strongly into our genes. Here's how I see it: if an organism arose which had this "death gene" turned off, it would not adapt to sudden changes in the environment. It might be susceptible to a novel infectious agent which wipes out the whole species. Thus evolution tends to weed out immortal or very long-lived organisms. Don't forget how natural selection works. It's not single creatures that adapt; it's about whole species. The only way for a species to adapt is for some of its individuals to die and be replaced by their offspring which differ genetically from their parents. Evolution needs death to work. Hence death is built-in. Look at this scary graph (with a logarithmic y axis!): https://en.wikipedia.org/wiki/Gompertz%E2%80%93Makeham_law_of_mortality#/media/File:USGompertzCurve.svg https://en.wikipedia.org/wiki/Gompertz%E2%80%93Makeham_law_o... and then tell me that medical advances will do anything to make you live to 200. Go on, I dare ya.
- alejohausner 11y agoThis also gets me thinking about pesticides in apples, of all things. I read Michael Pollan's "The Botany of Desire" a while ago, and was really struck by the story of Johnny Appleseed. For those of you who didn't grow up in the USA, he travelled through the country planting apple seeds, so that later settlers would find whole apple orchards in place when they moved in. The interesting thing is that apples don't "spring true" from seed. In other words, an tree that bears sweet apples will almost certainly have seeds that lack the gene for sweetness. Apple trees grown from seed will certainly bear crab apples. They are sour, and are only good for fermenting and making alcoholic apple cider. Settlers were certainly happy to have crab apples, because cider is fun and easy to make. But they certainly didn't eat those apples. If you want sweet apples, you have to use grafting: if you are lucky enough to get a tree with sweet apples, you will probably immortalize it, but taking cuttings from its branches, and grafting them onto ordinary crab-apple root stock. The part of the tree above ground will be genetically different from the part below. If the root stock nears death, you'll take cuttings from the part above ground and graft them onto new roots. This is all very nice, but it sidesteps evolution: you've created an immortal organism, which won't be able to fight off insects, fungus, and bacteria that attack apples, and which are constantly evolving to overcome a plant's defenses. Since the tree can't generate new chemicals that kill or repel these attackers, humans have to invent fungicides and insecticides to do it for them. That's why apple farming relies so heavily on spraying scary chemicals on the trees. Any war you declare on time and change is a war you will lose.
- bane 11y agoYou know, I'm okay with this body not lasting. I'm not too terribly fond of it anyway. I just want a good and working migration plan.
- tim333 11y agoYeah, I second that. In most religious belief your soul or some part of you lives on. And some people think you can contact them with seances and that the spirits can influence what happens here. I don't see why we can't build an electronic version of that in the future.
- Symmetry 11y agoIn terms of mechanisms for aging I think Nick Lane has some pretty good arguments that it mostly has to do with evolution in your body's population of mitochondria. The evidence with the unexpectedly long lives of hummingbirds is at least suggestive. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1483179/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1483179/
- norea-armozel 11y agoFor me, death is just another fact of life but I don't think dying from old age will be one of those facts that will be around for much longer (in terms of a century). Yet diseases, accidents, and murder will still be there to cut life short to be sure. I just think it's odd that there's a great many essays on the matter of death where people argue it's preferable to accept it than to fight it even if it's futile. I'd rather go out with a bang than a whimper. At least then I know I tried and I didn't let death off too easy.
- douche 11y agoI don't remember where I originally picked this up, but I recall reading that generally, for warm-blooded mammals, there is a pretty strong correlation between resting heart rate and lifespan. Except that humans are a huge outlier. Ah, here's the graph, possibly not from the most reputable source, but it's what the googles found me first http://www.runnersworld.com/sweat-science/how-many-heart-beats-do-we-get http://www.runnersworld.com/sweat-science/how-many-heart-bea... I do sometimes wonder if the delaying of child-rearing has some effect on lifespan. Historically, it's not uncommon to find mothers and fathers in their mid teens, and adulthood was commonly understood to start at something like 16 or 18. In western countries, we're deferring child-rearing into the late twenties, early thirties, and full adulthood keeps creeping upwards as well.
- dang 11y agohttps://news.ycombinator.com/item?id=9414176 https://news.ycombinator.com/item?id=9414176