Leanness & Aging

A number of studies suggest that permanent calorie restriction (which isn't healthy and isn't something I recommend) can help extend the lifespan.  Yet researchers haven't been sure whether the effect was due to the subjects eating less or the resulting leanness of the subjects.

Some neat research has separated out the effects and shown that leanness does in fact extend the lifespan (at least in animal subjects).  Scientists were able to flip a genetic "switch" that let mice eat all they want yet still remain lean.

I have been curious about this for some time, speculating that being overweight accelerates the aging process.  People who are older and lean often look younger than someone in their 20s who is overweight.

I have also been wondering what the "optimal" degree of leanness is.  Hunter-gatherers have between 8 - 11 percent bodyfat from what I've read.  I don't what my bodyfat it is, it's normal - maybe 15 percent.  I think after the summer is over here in Vegas I will embark on a mission to get my bodyfat in the 8 to 11 percent range.