X-Message-Number: 10615
Date: Mon, 19 Oct 1998 23:42:43 -0700
From: Brian Manning Delaney <>
Subject: Calorie Restriction
References: <>

Thomas Donaldson <> wrote:

> You are wrong in your statement that only
> Deprenyl has shown an increase in maximal
> lifespan.

(Just to be clear: that wasn't my statement, but from what you
say below I think you know that.)

> I will say, though, that a lot depends
> on just how you define it.

Yes, even among researchers, there are different operative
definitions of maximum life span. But the one you give here, and
the way you apply it, does not seem useful to me:

> IF we define maximal lifespan as the maximum
> lifespan of any animal in the drug versus the
> control group, then L-Dopa,melatonin,dilantin,
> and CoQ10 all show curves with the maximum
> lifespan reached by the treated animals.

I may not understand you, but you're describing a mortality curve
"squaring" effect, yes? I was referring to studies that an
intervention SURPASSESS maximum life span of control animals, not
just REACHES it.

Again, to stress: a drug which "squares the curve" is by no means
worthless. Such a drug, however, cannot (on the grounds of the
mortality changes produced alone) be argued to slow the aging
process. I don't know which studies you're thinking of above, but
the ones I'm familiar with on those substances show that
particular diseases don't strike at as early an age with the
drugs you mentioned. This is why more of the experimental animals
approach the maximum life span (and why average life span is
increased). An individual would need to ask whether or not s/he
is likely to get the particular disease, or diseases, affected by
the drug, before deciding to take the drug. (And there's a second
question: are these disease processes operative in the same way
in humans?) A drug that slowed aging per se, on the other hand,
is one that would confer a longevity benefit to anyone.

But if you think there are well-conducted studies that increase
maximum life span (relative to that achieved in controls) in
post-embryonic animals, please cite them. I know of none, with
the possible exception of the Deprenyl studies, as I mentioned.

I disagree with what you say here in elaborating your definition
of maximum life span:

> [...]As for defining "maximal lifespan",
> especially when the number of experiments on a
> drug or treatment is small, I find it difficult
> to work out any clear definition other than the
> one I gave. NO one keeps statistics on the
> lifespan of every lab mouse in existence, and
> such statistics are unlikely to mean very much
> anyway.

Actually, EXTREMELY careful data is kept on rodent life spans.
The mortality data on each commonly used strain has been charted

> As for the maximal lifespan of any lab
> mouse involved in an experiment with drug X,
> there are problems, too. The conditions in each
> experiment are unlikely to be identical, either
> in the strain of mouse or in their treatment and
> the treatment of controls.

Of course. That's why researchers use the same strain for a given
study, and will only VERY cautiously compare the mortality data
they get to that found in other studies, even studies using the
same species. (But, since such careful data is kept for most
strains, when a dramatic gain in life span is found, a comparison
with the record for the strain is usually noted, at least.)

Regardless, nothing you've said supports your earlier claim that
there are drugs which produce an effect ~equal to that of CR
started in adulthood. (But if I've misunderstood, please clarify,
and of course cite -- even roughly -- the studies. By the way,
you are probably a much better judge of what belongs on this list
than I, so feel free to email me the citations, if you think
others here are bored with/annoyed by this topic.)

I thus will again stress: No one should decide, right now, not to
practice CR solely out of the belief that we know that there is
some other regimen that can achieve the same longevity benefits
-- for such a belief currently has zero support.

> I will be blunt, not about what you say but
> about the current state of aging research: I
> think that the emphasis on calorie restriction,
> with little attempt to work out exactly why and
> how it has its effects, simply won't get us very
> far.

I don't know anyone who would disagree with you, as far as
research priorities go. Moreover, I don't know any researcher who
ISN'T doing precisely what you (along with, again, many people)
advocate: trying to find out how it works.

But in the sphere of advocacy of CHOICE of particular
life-extension regimens -- today, given the limits on our
knowledge -- I think CR hasn't been stressed ENOUGH.

A quick anecdote. I became seriously interested in life-extension
six years ago. I went to the medical library to learn more, and
was astonished to find that there weren't any studies supporting
the widespread claims about the effects anti-oxidants could have
on aging. Yet there were tons of studies on CR, showing dramatic
increases in maximum life span, even when started in adulthood.
Why, I wondered, was Roy Walford the only one seriously
advocating that people try this? (I've been told the Life Ext.
Foundation also pushed CR fairly heavily years back.)

I started Sci.life-extension partly to correct this problem.
Unfortunately, after a year or two, the group was so heavily
bombarded by ads that most of the serious researchers were driven

In the last year or so there's been an even more insidious
development in Sci.life-extension. At least two supplement
companies -- and I suspect several others -- pay people to
participate regularly, and frequently, in discussions in
Sci.life-extension and a few other health-oriented newsgroups.
That by itself, of course, wouldn't have to be a problem,
depending on the mandate given these employees. Yet, as it's
turned out, Sci.life-extension is becoming like an infomercial --
or rather "disinfomercial", as it seems to be. (Notable
non-disinfomercialists, among the frequent posters, include
Aubrey de Grey, James Ryley, and Steve Harris -- there a few
among the newer participants, too.) Instead of the spam we had
three or four years ago -- a one-line pointer to a URL about
"super-antioxidants" -- we now have people posting actual claims,
even with loosely connected Medline abstracts appended to give
the appearance of a scientific basis for the claim (an appearance
which is of course accurate in some cases, as with all
well-crafted infomercials -- though I'm not sure the proportion
of relevant abstracts exceeds that which one would expect from
random posting of merely keyword-matched abstracts).

It's astonishing.

Thus, until research comes up with something better than, or even
equal to, CR, I think CR should be stressed MORE. Most people
will not want to be on strict CR, but some will, and plenty of
people would be willing to be on moderate CR (so goes my
experience with CR advocacy). Making it widely known that CR is
more likely, by FAR, based on what we know now, to add years to
life than any other purported life-ext. regimen will save lives.
(Alas -- it won't make money, though!!)

This doesn't mean that we shouldn't also be pursuing research to
find something that can equal or surpass CR. Indeed, we very much
should be pursuing such research. Fortunately, many, many people
are doing just that. I hope success comes soon (if only to quiet
my inner Homer Simpson: "Choooooocolate...").

Best wishes,

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