8 ms·

Your body wasn’t built to last: Math of human mortality (2009)

88 points by lighttower 9y ago

GarvielLoken 9y ago
Another useless scientific article about obvious things. Yes, you have a higher chance of dying when you get older, is this really a "news" we need on HackerNews? Notice that the article doesn't even offer new facts, only statistical observations.
- dang 9y ago
  Please don't post snarky dismissals of other people's work. This breaks the HN guideline which asks: "Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize." That principle applies as well to articles as to persons, and there's clearly more in this piece than you reduced it to. But even if you were right, the combination of an empty comment and an acidic pH makes for a sourer website, and the internet is hostile enough already. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
- ACow_Adonis 9y ago
  Statistical observations are new facts to those who did previously have knowledge of them.
- golergka 9y ago
  > Yes, you have a higher chance of dying when you get older, is this really a "news" we need on HackerNews? The nature of this connection can be different. This is what discussed in the article. > Notice that the article doesn't even offer new facts, only statistical observations. Statistical observations are facts.
dingo_bat 9y ago
Your body was also not built to travel to the moon and drive a buggy on the surface. Didn't stop us though.
mamon 9y ago
It is quite obvious that living organisms are not build to last - we are supposed to live just long enough to produce and raise some offsprings.
- golergka 9y ago
  We are not supposed by anyone. We just happen to be as result of chaotic natural process.
  - wantstosaysome 9y ago
    I think it is like that for the survival of the species..
  - deleted 9y ago
    [deleted]
jankotek 9y ago
Isaac Asimov wrote in The Caves of Steel, that human body could last 300 years. But on special diet, in sterile environment...
- HiroshiSan 9y ago
  Jehoshaphat!
- AnimalMuppet 9y ago
  That was fiction, though. It wasn't actual science.
onurcel 9y ago
The Gompertz–Makeham law the author uses, actually allows also to modelize the accidental death rate. I don't know how hard it is to fit this additionnal parameter with real-world data though.
hacker_9 9y ago
In my opinion death is simply explained by the human body not having reached it's final form yet. We are constantly evolving, but evolution has been concentrating on short term survival for a millenia. It's only recently, in evolutionary terms, that long term life has become viable. I would say our healing abilities point to the fact that we are evolving along this path, and that it is also an obtainable goal, just look at the immortal jellyfish.
- julian55 9y ago
  Why would we evolve to love any longer than we currently do? We obviously need to live long enough to breed (i.e. to about 40) and probably having reasonably healthy grandparents may be an advantage but I can't see why we would be evolving to live any longer than that.
  - lqdc13 9y ago
    It might be that people enjoy living without children for as long as possible in the current western economic/cultural climate. This age might keep increasing because those who try too late won't reproduce. So it's passive selection for longevity.
    - golergka 9y ago
      I think it's passive selection for reproducing in your late teens or early twenties out of bad luck. Even a century ago, your wealth level had a tremendous impact on whether or not your prodigy will survive, so there was an evolutionary selection for social success; with modern welfare state, I don't think that there's any selection bias towards the wealthy.
    - philwelch 9y ago
      Or passive selection for not being part of an infertile and decadent culture.
  - k__ 9y ago
    Creating new humans is costly and risky. Maybe immortal humans give you a better bang for the buck.
reasonattlm 9y ago
Some other items worth considering in the context of why mortality rates look the way they do: https://doi.org/10.1006/jtbi.2001.2430 https://doi.org/10.1006/jtbi.2001.2430 "Reliability theory is a general theory about systems failure. It allows researchers to predict the age-related failure kinetics for a system of given architecture (reliability structure) and given reliability of its components. Reliability theory predicts that even those systems that are entirely composed of non-aging elements (with a constant failure rate) will nevertheless deteriorate (fail more often) with age, if these systems are redundant in irreplaceable elements. Aging, therefore, is a direct consequence of systems redundancy. The theory explains why mortality rates increase exponentially with age (the Gompertz law) in many species, by taking into account the initial flaws (defects) in newly formed systems." https://doi.org/10.1073/pnas.1714478115 https://doi.org/10.1073/pnas.1714478115 "For many cancer types, incidence rises rapidly with age as an apparent power law, supporting the idea that cancer is caused by a gradual accumulation of genetic mutations. Similarly, the incidence of many infectious diseases strongly increases with age. Here, combining data from immunology and epidemiology, we show that many of these dramatic age-related increases in incidence can be modeled based on immune system decline, rather than mutation accumulation. In humans, the thymus atrophies from infancy, resulting in an exponential decline in T cell production with a half-life of ∼16 years, which we use as the basis for a minimal mathematical model of disease incidence. Our model outperforms the power law model with the same number of fitting parameters in describing cancer incidence data across a wide spectrum of different cancers, and provides excellent fits to infectious disease data. This framework provides mechanistic insight into cancer emergence, suggesting that age-related decline in T cell output is a major risk factor." And of course the SENS synthesis of the compelling evidence for aging to be the consequence of accumulated damage of various sorts: http://www.sens.org/research/introduction-to-sens-research http://www.sens.org/research/introduction-to-sens-research "Many things go wrong with aging bodies, but at the root of them all is the burden of decades of unrepaired damage to the cellular and molecular structures that make up the functional units of our tissues. As each essential microscopic structure fails, tissue function becomes progressively compromised – imperceptibly at first, but ending in the slide into the diseases and disabilities of aging. Decades of research in aging people and experimental animals has established that there are no more than seven major classes of such cellular and molecular damage, shown in the table below. We can be confident that this list is complete, first and foremost because of the fact that scientists have not discovered any new kinds of aging damage in nearly a generation of research, despite the increasing number of centers and scientists dedicated to studying the matter, and the use of increasingly powerful tools to examine the aging body. In its own way, each of these kinds of damage make our bodies frail, and contribute to the rising frailty and ill-health that appears in our sixth decade of life and accelerates thereafter."
KasianFranks 9y ago
Google wants to use naked mole rats to conquer death https://www.popsci.com/naked-mole-rat-aging https://www.popsci.com/naked-mole-rat-aging + Recent advances in computational epigenetics https://www.dovepress.com/recent-advances-in-computational-epigenetics-peer-reviewed-article-AGG https://www.dovepress.com/recent-advances-in-computational-e... + End-to-end guide design for CRISPR/Cas9 with machine learning https://www.microsoft.com/en-us/research/project/crispr/ https://www.microsoft.com/en-us/research/project/crispr/ Will require new math.
YeGoblynQueenne 9y ago
Could someone send a link to that blog post to Ray Kurzweil? It's just because he loves exponential growth graphs so much. Just yesterday he was talking about the exponential growth in biotech that, within 10 years, will allow the entire population (of Silicon Valley? California? The US? The world?) to reach "longevity escape velocity" and live to see the coming century: https://youtu.be/9Z06rY3uvGY?t=27m20s https://youtu.be/9Z06rY3uvGY?t=27m20s
- wetpaws 9y ago
  Kurz is a nice guy, but he seems to be scared shitless of dying and getting more and more desperate with his estimations.
  - YeGoblynQueenne 9y ago
    To be honest, I'm scared shitless of dying also. I don't know why that is a reason to abandon reason and embrace bad statistics. I would even say that losing my ability to think clearly and arrive at probably approximately almost not completely ridiculously wrong conclusions is at least as terrifying as dying (or at least as terrifying as dying young in a horrible manner). Death is really scary shit and I get that someone with the money and connectionts of Kurzweil can convince himself that it won't happen to him, but we must all realise that, at this point, that's just a pipe dream.
    - wetpaws 9y ago
      I don't mind him toying with an idea of immortality within his lifetime if it takes an edge from the pain. You can even argue that it can be considered as a some kind of a personal religion, albeit more scientific. What I'm not happy is so many folks calling him a prophet and jumping this magic-nanothech-30year-singularity bandwagon.

88 points by lighttower 9y ago

Another useless scientific article about obvious things. Yes, you have a higher chance of dying when you get older, is this really a "news" we need on HackerNews? Notice that the article doesn't even offer new facts, only statistical observations.

dang 9y ago
Please don't post snarky dismissals of other people's work. This breaks the HN guideline which asks: "Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize." That principle applies as well to articles as to persons, and there's clearly more in this piece than you reduced it to. But even if you were right, the combination of an empty comment and an acidic pH makes for a sourer website, and the internet is hostile enough already. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
ACow_Adonis 9y ago
Statistical observations are new facts to those who did previously have knowledge of them.
golergka 9y ago
> Yes, you have a higher chance of dying when you get older, is this really a "news" we need on HackerNews? The nature of this connection can be different. This is what discussed in the article. > Notice that the article doesn't even offer new facts, only statistical observations. Statistical observations are facts.

dingo_bat 9y ago

Your body was also not built to travel to the moon and drive a buggy on the surface. Didn't stop us though.

mamon 9y ago

It is quite obvious that living organisms are not build to last - we are supposed to live just long enough to produce and raise some offsprings.

golergka 9y ago
We are not supposed by anyone. We just happen to be as result of chaotic natural process.
- wantstosaysome 9y ago
  I think it is like that for the survival of the species..
- deleted 9y ago
  [deleted]

jankotek 9y ago

Isaac Asimov wrote in The Caves of Steel, that human body could last 300 years. But on special diet, in sterile environment...

HiroshiSan 9y ago
Jehoshaphat!
AnimalMuppet 9y ago
That was fiction, though. It wasn't actual science.

onurcel 9y ago

The Gompertz–Makeham law the author uses, actually allows also to modelize the accidental death rate. I don't know how hard it is to fit this additionnal parameter with real-world data though.

hacker_9 9y ago

In my opinion death is simply explained by the human body not having reached it's final form yet. We are constantly evolving, but evolution has been concentrating on short term survival for a millenia. It's only recently, in evolutionary terms, that long term life has become viable. I would say our healing abilities point to the fact that we are evolving along this path, and that it is also an obtainable goal, just look at the immortal jellyfish.

julian55 9y ago
Why would we evolve to love any longer than we currently do? We obviously need to live long enough to breed (i.e. to about 40) and probably having reasonably healthy grandparents may be an advantage but I can't see why we would be evolving to live any longer than that.
- lqdc13 9y ago
  It might be that people enjoy living without children for as long as possible in the current western economic/cultural climate. This age might keep increasing because those who try too late won't reproduce. So it's passive selection for longevity.
  - golergka 9y ago
    I think it's passive selection for reproducing in your late teens or early twenties out of bad luck. Even a century ago, your wealth level had a tremendous impact on whether or not your prodigy will survive, so there was an evolutionary selection for social success; with modern welfare state, I don't think that there's any selection bias towards the wealthy.
  - philwelch 9y ago
    Or passive selection for not being part of an infertile and decadent culture.
- k__ 9y ago
  Creating new humans is costly and risky. Maybe immortal humans give you a better bang for the buck.

reasonattlm 9y ago

Some other items worth considering in the context of why mortality rates look the way they do: https://doi.org/10.1006/jtbi.2001.2430 https://doi.org/10.1006/jtbi.2001.2430 "Reliability theory is a general theory about systems failure. It allows researchers to predict the age-related failure kinetics for a system of given architecture (reliability structure) and given reliability of its components. Reliability theory predicts that even those systems that are entirely composed of non-aging elements (with a constant failure rate) will nevertheless deteriorate (fail more often) with age, if these systems are redundant in irreplaceable elements. Aging, therefore, is a direct consequence of systems redundancy. The theory explains why mortality rates increase exponentially with age (the Gompertz law) in many species, by taking into account the initial flaws (defects) in newly formed systems." https://doi.org/10.1073/pnas.1714478115 https://doi.org/10.1073/pnas.1714478115 "For many cancer types, incidence rises rapidly with age as an apparent power law, supporting the idea that cancer is caused by a gradual accumulation of genetic mutations. Similarly, the incidence of many infectious diseases strongly increases with age. Here, combining data from immunology and epidemiology, we show that many of these dramatic age-related increases in incidence can be modeled based on immune system decline, rather than mutation accumulation. In humans, the thymus atrophies from infancy, resulting in an exponential decline in T cell production with a half-life of ∼16 years, which we use as the basis for a minimal mathematical model of disease incidence. Our model outperforms the power law model with the same number of fitting parameters in describing cancer incidence data across a wide spectrum of different cancers, and provides excellent fits to infectious disease data. This framework provides mechanistic insight into cancer emergence, suggesting that age-related decline in T cell output is a major risk factor." And of course the SENS synthesis of the compelling evidence for aging to be the consequence of accumulated damage of various sorts: http://www.sens.org/research/introduction-to-sens-research http://www.sens.org/research/introduction-to-sens-research "Many things go wrong with aging bodies, but at the root of them all is the burden of decades of unrepaired damage to the cellular and molecular structures that make up the functional units of our tissues. As each essential microscopic structure fails, tissue function becomes progressively compromised – imperceptibly at first, but ending in the slide into the diseases and disabilities of aging. Decades of research in aging people and experimental animals has established that there are no more than seven major classes of such cellular and molecular damage, shown in the table below. We can be confident that this list is complete, first and foremost because of the fact that scientists have not discovered any new kinds of aging damage in nearly a generation of research, despite the increasing number of centers and scientists dedicated to studying the matter, and the use of increasingly powerful tools to examine the aging body. In its own way, each of these kinds of damage make our bodies frail, and contribute to the rising frailty and ill-health that appears in our sixth decade of life and accelerates thereafter."

KasianFranks 9y ago

Google wants to use naked mole rats to conquer death https://www.popsci.com/naked-mole-rat-aging https://www.popsci.com/naked-mole-rat-aging + Recent advances in computational epigenetics https://www.dovepress.com/recent-advances-in-computational-epigenetics-peer-reviewed-article-AGG https://www.dovepress.com/recent-advances-in-computational-e... + End-to-end guide design for CRISPR/Cas9 with machine learning https://www.microsoft.com/en-us/research/project/crispr/ https://www.microsoft.com/en-us/research/project/crispr/ Will require new math.

YeGoblynQueenne 9y ago

Could someone send a link to that blog post to Ray Kurzweil? It's just because he loves exponential growth graphs so much. Just yesterday he was talking about the exponential growth in biotech that, within 10 years, will allow the entire population (of Silicon Valley? California? The US? The world?) to reach "longevity escape velocity" and live to see the coming century: https://youtu.be/9Z06rY3uvGY?t=27m20s https://youtu.be/9Z06rY3uvGY?t=27m20s

wetpaws 9y ago
Kurz is a nice guy, but he seems to be scared shitless of dying and getting more and more desperate with his estimations.
- YeGoblynQueenne 9y ago
  To be honest, I'm scared shitless of dying also. I don't know why that is a reason to abandon reason and embrace bad statistics. I would even say that losing my ability to think clearly and arrive at probably approximately almost not completely ridiculously wrong conclusions is at least as terrifying as dying (or at least as terrifying as dying young in a horrible manner). Death is really scary shit and I get that someone with the money and connectionts of Kurzweil can convince himself that it won't happen to him, but we must all realise that, at this point, that's just a pipe dream.
  - wetpaws 9y ago
    I don't mind him toying with an idea of immortality within his lifetime if it takes an edge from the pain. You can even argue that it can be considered as a some kind of a personal religion, albeit more scientific. What I'm not happy is so many folks calling him a prophet and jumping this magic-nanothech-30year-singularity bandwagon.