Chill out, live longer? How do VLC & caloric restriction factor in?

I've been working on a related post when I came across an interesting study that I thought was worth a blog  post on by its own and was more timely for other studies I've been looking at more recently. A sidebar of looking into the claims of L.Ron Rosedale is that he's really all about longevity and believes his diet will deliver on that promise.  What I'm about to say may shock  some of you, but, there's some evidence out there that he might just be right!   The Catch 22, however, is that where he's correct it flies in direct conflict to the claims and theories espoused by the other ardent evangelists of carbohydrate restriction.  

Any research into aging and longevity these days inevitably lands one into a sea of studies on teeny tiny worms known as C. elegans.   I have some stuff in the pike on these worms, but basically, two ways of  "naturally" extending the lifespans of wild type C. elegans are (1) growing them under lower temperature conditions, and (2) forcing the worms through a dauer state (essentially dormant) developmental phase as larva through "starvation".  Both of these manipulations have the effect of producing adult worms with reduced metabolic rate.  (Worms are not intended to be the topic of this post, but here is one review on metabolic rate and longevity for those interested).  The other popular species for longevity experiments is mice.  Caloric restriction in mice has resulted in extended lifespan coupled with a reduced metabolic rate.  At first glance, run hotter/faster, burn out, run cooler/slower ... fade away?

In any case, with worms, the body temperature is easily controlled by manipulating the environmental temperature.  But what of warm blooded animals?  You put a warm blooded animal in a cold environment and their metabolism increases.  In the case of small animals like mice, they are blessed with relatively (to total fat and body mass) large amounts of brown fat (BAT) which is the thermogenic fat in such animals.  As an aside, the original uncoupling protein (UCP1) is that which generates heat in BAT.  Warm blooded animals have a vested interest in keeping their body temperatures within a relatively narrow operating range.  So ... you put a worm in a cold climate and it's metabolism goes down, you put a mouse in one, and it goes up.  A transgenic mouse to the rescue!

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