CR vs Brain Cancer

Tom Matthews tom at
Sat Jun 29 15:06:01 EST 2002

Please learn to respond "inline". That method is preferable because one can 
clearly see to what each of your responses is related, and is it also less 
possible for you to skip past some part of the previous response without 
addressing important points. Sometimes this may be unintentional and innocent, 
but often it is deceitfully used as means of "escaping" a point that cannot 
effectively be answered.

Kenneth Collins wrote:

> admitting that i should've quoted what was said in the original post, which
> is what you said in your reply to my post, i stand on what i've posted.
> i've yet to see any experiment design that cannot be improved.

Granted. But CR experiments have been done and redesigned for several decades 
now. Many improvements have taken place during that time and many deficiencies 
have been corrected.

> it could be that something like the requirement for minimal-feeding has the
> 'inadvertant' effect of diminishing contamination relative to the
> all-you-can-eat subjects' food-in-abundance that just sits-there, absorbing
> air-born pathogens, chemo and decay factors, etc. in the lab. anyone can
> sense this possibility by just taking a wiff of the air in an animal lab.
> supplying minimal food, always from a relatively-fresh supply, =might= have
> an impact.
> it could be that there're nutrients in the food, which in small
> concentrations, is 'good', but in larger concentrations, is 'bad'. there're
> many such substances. it could be that the minimal-feeding just 'hits the
> mark' with respect to such substances.
> and it's a =certainty= that the relative-ease of being in an all-you-can-eat
> environment results in an artificially-imposed TD E/I-minimization 'state',

It would help if you defined "TD E/I-minimization".

> and that this 'reverberates' throughout correlated nervous systems,
> impacting all manner of neurally-mediated processes.
> artificially-imposed relative-ease 'dulls' everything else, including
> immune-system function [which, itself constitutes a nervous-system-mediated
> form of 'cognition']. could be that the all-you-can-eat rats just die from
> 'boredom'.

These are excellent points and are all possible. Whether some of them have been 
looked at I don't know. Perhaps Michael Rae who is much more thoroughly familiar 
with CR research could answer that question.
However, the CR animals have multiple mechanistic differences with the ad lib 
fed controls (of controls are *not* ad lib fed but are on 10% restriction just 
so that over-feeding is not a factor) which could all contribute to the 
longevity effect. Furthermore, recent studies have shown that a gene expression 
change takes place very quickly after CR is begun, long before some of the 
processes which you have mentioned above would be likely to have an effect.

> it goes =on-and-on= like this.
> because of any individual nervous system's inherent tight-integration,
> =every= such problem is tightly-coupled to everything else that's going-on
> in-there.

Again, I agree. Unfortunately it is not possible to do fully "placebo" CR.
Still the effect has been so robust that it is unlikely, IMO, that any major 
extraneous factors are the reason for its existence.

> there're loose-ends aplenty.

 From my reading, I don't agree. There are very few of any likely significance, 
IMO. The major one, IMO, is the fact that all animals tested so far have rather 
short lifespans and the mechanisms of the effect may already be so much more 
optimized in a longer lived species such as humans, that CR will not accomplish 
much additional longevity, even though it will still be a highly beneficial 
anti-morbidity/mortality agent (ie. it will likely extend the years of robust 
health of those practicing it except for the ones who would have lived to a very 
old age anyway).

> it's the essence of Science to eliminate them, in all experiments [this,
> too, is 'just' TD E/I-minimization].

Again, I don't know what you mean by the last abbreviation.


> Cheers, Tom, ken [k. p. collins]
> Tom Matthews wrote in message <3D1DE589.3020802 at>...
>>Kenneth Collins wrote:
>>>there are a lot of 'loose-ends' in what, i agree, is a general approach
>>> that needs to be explored.
>>>the first thing that needs to be kept in mind is that simple
>>>calorie-restriction doesn't prolong Life [Africa, North Korea],
>>You are confusing calorie restriction (restriction of calories *only*) with
>>dietary restriction (restriction of the end spectrum of dietary nutrients.
>>Furthermore, the diets of some of the peoples in the regions that you
>>mention are additionally restricted in many of the essential nutrients such
>>as protein for example. So this confusion does not occur some people practicing
>>calorie restriction call it CRAN (calorie restriction with adequate nutrition)

>>and some even call it CRON (calorie restriction with optimal nutrition).

>>However, I think
>>the last is rather pretentious because no one currently even knows what is
>>optimal nutrition much less is able to achieve it.
>>With respect to calorie restriction, there really are no "loose ends".
>>>so, perhaps
>>>what's happening is that calorie-reduction induces an organism to
>>>range-more-widely with respect to what it will accept as 'food', and that
>>>it's such wide-ranging-ness that results in bringing micronutrients into
>>>a system that would've, otherwise, taken-the-easy-route with respect to
>>>'food'... just eat what's there-in-abundance, missing the micronutrients
>>>that're not-there, within the abundance.
>>No. All calorie restriction experiments are done under controlled
>>conditions on
>>laboratory fed animals. No "ranging more widely" is possible.
>>>lab subjects, for instance, might ingest wood-shavings stuff, for
>>>and there might be something in-there that is what makes the difference.
>>Not likely, and they are not always housed with anything which is in any
>>edible. The researchers are not so stupid not to have thought of such
>>>i'm not saying that the ingestion of wood-shafvings stuff =is= what's
>>>i just wanted to point out all the loose-ends stuff that needs to be
>>That they have been controlled is proven by multiple repeated experiments.
>>>for instance, it's a virtual certainty that humans who choose to
>>>calorie intake do not just restrict calorie intake. they simultaneously
>>>choose better foods, containing a wider range of nutrients.
>>Not all of them, but they mainly do so in order to *maintain* their intake
>>all nutrients *except* calories. To the extent that they select even better
>>foods and nutrients they should get effects additive to simple CR.
>>--Tom Matthews
>>MoreLife for the rational -
>>Reality based tools for More Life in quantity & quality

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