[ExI] Does caloric restriction work for humans?

[Alejandro Dubrovsky]

On Fri, 2009-12-11 at 10:10 -0600, Max More wrote:
> I've been skeptical about drastic CR for humans for years. One 
> reason, mentioned in the following article, is that we don't live in 
> cages in a lab. Lacking any spare muscle or fat makes us highly 
> vulnerable to traumas of various kinds. (Many of us know of -- or are 
> -- people who have lost 30 pounds or more in hospital due to 
> illness). Recently, Aubrey has given a specific reason (also 
> mentioned in the article) why the life extension from even severe 
> caloric restriction is likely to be very small.
> 
> So, here's the article. I would like to hear your thoughts on it, pro 
> and con. If CR advocates have directly addressed all the points, I'd 
> appreciate a pointer.
> 
> Calorie restrictive eating for longer life? The story we didn't hear 
> in the news
> http://junkfoodscience.blogspot.com/2009/07/calorie-restrictive-eating-for-longer.html
> 

While total mortality didn't reach statistical significance at p 0.05,
the numbers look highly sugestive to me. There's been 21 deaths in the
control group and 14 in the CR group.  ie total mortality was a third
lower in CR but because the sample is tiny, it's hard to reach 0.05.
Those non-aging deaths were 7 in control vs 9 in CR (included in totals
above). 

4 cases of cancer in CR v 8 in control.   Later onset age of disease.
Researchers claim the CR monkeys look in much better shape. Seems like a
pretty decent effect to me, and you'd have to be a strict frequentist to
call this a null study.   If you were expecting CR to be completely
useless, I'd think this should point at it being of some effect.  If you
thought that it'd extend lifespan by 30% like it does in some mice
breeds, then this should probably point you in the other direction.  I
expect most people here expect it to be somewhere in between, and this
seems like confirming those expectations.