No Cap On Life Expectancy?

Samarkind writes "An article over at Science Daily (no registration req'd) talks about the average life expectancy for people going up all over the world by an average of 3 months per year. They also say that the somewhat pervasive idea that people can only live so long just isn't true. The kicker that I got from the article was that the average life expectancy for men is 65... isn't that about when I'll retire?" Remember the life expectancy includes all the people who die at age 2 or 15 or 21. If you make it past 25 or so, you've got good odds to make it to 80.

Comments

we need to get that up...

[Polo]

We need to get that up to over 1 year per year.

Cause not stated

[crow]

One shortcoming of the article is that the cause for the increase is not stated. Many causes for increasing life expectancy have no implications regarding a maximum lifespan. If all we're doing is reducing early deaths through improved vaccinations and safety, then we've made no progress in disproving the idea of a maximum lifespan.

Another way of looking at it would be: The life expectancy for people born today is higher than for people born twenty years ago. That doesn't mean that the life expectancy for people who are 60 today is any better than the life expectancy for people who were 60 twenty years ago.

Re:Cause not stated

[mlinksva]

I suspect the life expectancy for people 60 today is significantly better than life expectancy for 60 year olds 20 years ago, otherwise we wouldn't be seeing an explosion of 65+ year olds (and 80+ and 100+). For there to really be "no cap" on life expectancy though, the maximum human lifespan needs to increase. AFAIK there are no documented cases of humans living much beyond 120. However, at only 3 months/year increase in life expectancy, we won't hit that barrier in this century. By that time (well before it) we'll have figured out how to significantly increase biological human lifespan. If you don't want to count on any such progress, calorie restriction seems to be the only current method we have of possibly extending maximum lifespan. At the other extreme, you could just wait for the singularity to obviate the need for biology.

Like I've always said...

[stienman]

...I plan on living forever.

So far, so good.

-Adam

Oldest living human?

[crow]

So if the conclusions of this study are true, not only should we see life expectancy continue to rise, but we should be frequently setting new records for the oldest living human.

A few years ago, the oldest person in modern history died in France at an age something like 122. Will that record be 150 in a hundred years?

Unfortunately, accurate age information was not available for the general population until the previous century, so we don't really know what the change in that record has been for a statistically-valid period of time. (Besides, when looking at one in billions, it's hard to say you're being statistically valid.)

Something seems off here...

[realgone]

From reading the article, it looks like this claim is based only on statistical analysis of life expectancy data. More specifically (from the article):

In their study, Vaupel and Oeppen reviewed longevity data from developed countries, including Australia, Iceland, Japan, the Netherlands, Norway, Sweden, Switzerland and the U.S. They found that life expectancy in such countries is steadily increasing by three months a year, per year.

"The key issue for policymakers to understand from our study is that there appears to be no finite limit to life expectancy," says Vaupel

Somehow, reaching that conclusion from that data seems incorrect. Just because a value is increasing at a steady rate doesn't mean it will continue to do so. Simple example: a dropped object will accelerate for a time then hit terminal velocity (in a real-world situation).

The fact that our life expectancy continues to increase may simply indicate our lifespans haven't yet hit their "terminal velocity" (as determined by biological/environmental factors).

In other words, they ain't dropping us from high enough yet. =)

Re:Something seems off here...

[nucal]

Exactly - from the article: The researchers emphasize they are not saying there is no limit to the rise in life expectancy. "There may or may not be some limit at some advanced age -- it is impossible to tell given current empirical data and theoretical knowledge," added Vaupel. "What is clear is that there is no limit that we are about to bump up against."

In other words we're a long way from reaching the limit to life span - which is important for policy makers and actuaries. But, this does not mean that there is no limit to life span, in the absence of other interventions. In fact, life span has a significant genetic component which has been studied in a lot of different organsms, like fruit files and worms where lifespan is controlled by the daf gene family.

In the worm case, it's not the accumulated insults of living that cause death, instead it's like throwing a switch. Alter the switch and you alter life span without changing quality of life. What causes the daf genes to get activated is still not well understood, but it might relate to the timing of having progeny ... after the worms reproduce they tend to die off, while mutant long lived worms tend to put off reproduction. Here are some labs working in aging research)

The old problem

[quantax]

Its good that our lifespans are increasing, however with the current over-population issues, this is a definate double-edge sword. With increased lifespans, we'd have to rework retirement since theres no way that the workforce can support a massive increase in elderly people. The current age for retirement is suited for the current 'normal' lifespan, but would fall apart if we started living 80+ years on average. The economy works because a majority of your population is either working or going to be working. If that balance shifted, where the non-working force was greater than that of the current working force, the problems would be endless. With increased lifespan must come increased retirement. But as we know, most people are definately ready for retirement by 60, and their bodies (and their state of being) is what determines this. If we could both increase lifespan *AND* reduce the aging of the body over that period of time, we would have the best of both worlds. This is by no means impossible, but will really determine if long-living en-mass is a real possibility or not.

For Discover subscribers...

[pythorlh]

There is an interesting article in the current issue of Discover magazine. It's not on the website yet, since that's still last month's issue.

Anyway, apparantly some species of turtle do not age. The only apparent change in their physiology is that the lay more eggs as they grow older. They apparently get smarter, as well. The enzyme that prevents cancer cells from dying of old age seem to give the turtle cells a boost when they are young, but they still don't get cancer, or other age-related diseases. We might break the 1-year/year barrier, yet! :)

Longevity is all well and good...

[Anonymous Codger]

...but what is more important is maintaining a decent quality of life as we age. There's a Greek myth about the goddess Eos, who falls in love with a mortal and asks Zeus to make him immortal. Alas, she neglected to ask that he also stay youthful. He continued to age but death could not reach him.

I have several friends who are caring for parents with Alzheimers and other diseases that don't kill right away but that destroy life in the most fundamental way. I know other elderly people who have suffered heart attacks and strokes and are all there mentally, but are in constant pain and have to severely restrict their activities. A few decades ago these diseases would have killed their victims. Now they wound them and often leave them in a state like poor Tithonus, lover of Eos.

I certainly wouldn't wish an earlier death on any of these people, rather I hope that the medical establishment can come up with ways to help people stay active, lucid, and happy as their bodies age beyond the point that most people reached in the past. This is as important as, perhaps more important than, extending life.