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Comment by icebraining | Hacker News Reader

"Ignoring, of course, the upward shift in the lifetime distribution that will result from future medical advances."

Have 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.

The distinction you are making is a bit artificial.

Not 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.

I 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?

It'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.

So, 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?

> 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.

People 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).

People 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_deat...

It's not artificial at all. Lifespan is a distribution, what OP describes is moving the distribution around a bit without moving the bounds.

What if there are no upper bounds, and all there is to work with is the distribution?

Do we have any evidence for that view? There is at least some evidence for the converse.

What 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.

Telomere 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.

I'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.

Artificial hearts is the most obvious example.

Not 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.

I 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.

You 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)

You 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.

I'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.

If 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.

Given 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.

Report 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.

Did you catch this:

http://www.sciencedaily.com/releases/2015/08/150831001112.ht...

That 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".

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.

Thank you. Yes, that makes a lot of assumptions.

Let's also not forget future dietary advances.

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