Antiaging Research Priorities [was Re: Major Criticisms of
james at nospam.com
Fri Sep 18 19:27:16 EST 1998
> > In humans the maximum lifespan observed in the
> > wild without researcher intervention is 122 years.
> (Technically, some would argue that anyone living beyond 115
> is a statistical "outlier," but that's a minor point.)
> > In your examples if the treatment used allows a
> > person to live significantly longer than 122
> > years then the treatment has altered the basic
> > genetic control of the aging process and you
> > will probably be receiving a Nobel Prize.
> This is where I don't get your reasoning. It's almost as if
> you're ruling out "nurture's" role in aging, or ruling out
> the existence of a broad range of environmental conditions
> under which different genes can find expression. Why
> couldn't it be the case, for example, that 1) as a response
> to conditions of food scarcity, mammals (and perhaps all
> living things) evolved the ability (i.e., developed the
> GENETIC changes necessary for the ability) to retard aging
> until more food is available, and 2) humans who have lived
> to 115-120 haven't had these genes expressed (or haven't had
> them expressed in the right way) consistently enough to live
> beyond ~120?
> In other words, I see no evidence to rule out the follow
> theory: Humans on fairly strict CR started in early
> adulthood could live 20-35% longer than the maximum life
> span as we've defined it. Some would argue that those living
> being 105 or so actually did practice a mild, inconsistent
> (and inadvertent) CR. (Call it a mild, inconsistent
> "researcher intervention".) If so, than we could expect CR
> to get us only to 126-142 or so. If not, CR could get us to
> 146-162. Either way, I'd call that an extension of maximum
> life span.
I have to agree with Tom's interpretation of the human numbers, though I
think it's not really the point of the discussion. We have a LOT of
data on humans, because there are so many of them and we've been
watching them for so long. I don't think ~120 is going to be broken by
CR. Obviously the more observations you make the closer your observed
maximum lifespan is going to get to the absolute genetic potential.
We've observed so many humans that a least a few of them must have
approximated CR pretty well. I think that we have seen the limits of
genetic potential in humans.
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