>> In article <3602A142.514CD024 at notarealaddr.ess>, bmdelaney at notarealaddr.ess> says...
> >Thomas Mahoney wrote:
> >> In article <36021FF5.2CF95D48 at notarealaddr.ess>,
> >> bmdelaney at notarealaddr.ess says...
> >>> Thomas Mahoney/ Excelife wrote:
> >>>> Quite correct. Mice in the wild undoubtedly
> >>>> encounter periods where food is scarce and the
> >>>> effects seen in CR are likely an adaptive
> >>>> response to these conditions. Thus the actual
> >>>> life span of the mice is that seen in CR.
> >>>I'm not sure how this way of looking at it is helpful.
> >>>Take another example. Say we had evolved a mechanism whereby
> >>>eating a certain substance found in a now rare plant turns
> >>>on telomerase in enough cells, in the right way, to slow
> >>>aging. No one has been known to eat the substnce because our
> >>>dietary habits over the last few centuries have precluded
> >>>its consumption. But suddenly we discover it, and people
> >>>start taking it and living to be 140 years old. Since this
> >>>ability to age slowly under the conditions of the presence
> >>>of this substance is an evolutionary adaptive response,
> >>>would you say people living to 140 by means of this
> >>>substance aren't extending their life span?
> >> Here you changed the premise. By stating that
> >> they lived to 140 you have, by definition,
> >> increased the maximum life span in humans.
> >I don't get it. You seem to be operating with two
> >definitions of maximum life span: 1) the longest an animal
> >(of a particular species) can live under conditions like any
> >of those which originally selected for an adaptive
> >anti-aging response (see your quote, above); and 2) the
> >longest any member of a species has lived.
> >If we adopt (1), then you are wrong that I've changed the
> >premise. The point of the example was to show just that.
> >As for (2), I can't see how this definition ever would be
> >useful. If I invent a drug that lets people live to 180,
> >then, under this definition, I can't say that the drug
> >extends human maximum life span after the first person has
> >taken it. Doesn't seem helpful. Wouldn't we want to say the
> >second and third people taking it are also living beyond the
> >human maximum life span? The second and third aren't
> >BREAKING RECORDS, sure, but that's something different.
>> The definition of life span provided by James, "maximum lifespan observed in
> the wild without researcher intervention", is appropriate and very close to
> what I've been trying to say.
>> Some mice in the wild undoubtedly encounter conditions very close to that
> achieved by calorie/dietary restrictions. Full laboratory controlled CR may
> provide a slight incremental increase in life span for mice but that's more
> an artifact of the experiment than any fundamental break through.
>> In humans the maximum lifespan observed in the wild without researcher
> intervention is 122 years.
>> 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
>> If, however, the treatment only improves the likelihood of living up to 122
> years in a healthier body then you are increasing life expectancy and
> improving the quality of life. You'll probably get rich but forget the
>> James and others feel that we should prioritize and concentrate our efforts
> on the latter research areas in the hopes that by increasing life expectancy
> by 20 or more years we might then be around when the the research into the
> genetic control of life span finally achieves results.
>> I think the genetic control of aging and lifespan has already been described
> and that research efforts to develop therapies based on this discovery should
> be our number one priority.
>>>> Thomas Mahoney, Pres.
> Lifeline Laboratories, Inc.
I'm only a layman, so please excuse my naivety, but it sounds to me like
the fundamental question in this debate might be stated as follows:
If a person alive today is 120 yrs. old, is it because their
environment, lifestyle, genetic heritage, etc., has allowed them to
simply avoid the causes of death that normally limit life span, or is it
actually due to a slower rate of aging, which would, from my neophyte
perspective, simply delay the usual causes of death?
If a 120 yr. old person alive today is really 120 yrs. old (according to
some generally agreed upon set of aging biomarkers), then, everything
else being equal, CR, if it had been applied over a significant portion
of this persons life span, would have slowed down the aging process, and
120 yrs. may have become 160 yrs., right?