My grandmother used to say that if you only ate foods you didn't really like, you'd never get fat. My grandmother wasn't a very happy person. She was, however, thin.

I like tourist's answer, especially the last part.

  At 28 I find myself just beginning to shift my focus into making Ashtanga a regular part of my life.  That being said I have spent some time looking at the consept of spiritual developement and diet.  I do consider the journy of Ashtanga a spiritual one.

  I've recently read through a book called 'The Genotype Diet', it theorizes that each of us fit into one of 6 Body types.  Each body type has an optimal diet.  There are certain foods each should have.. also ones that certain types shoudln't.  Its possible that as we age we become more sensible to our genotype.  If we practice Ashtanga on a consistant basis.. we are infusing our bodies with an energy that is transformative in nature.  Our hunger could be the result of our bodies craving certain things we are not getting.  We may thing that we simply need to eat more.. when in a sense we just need to eat differently.

  Another one of my callings I resonate hightly is Reiki.. any of you that are curious.. just WIKI it... as I do not want to become side tracked from my point... My Theory is... as our bodies obsorb more of what they need from an etheric source... we require less food stuffs to maintain ourselves because of what we are getting from the etheric sources.  There is further evidence of this from those who practice Sungazing.  There are people who claim to require no food at all, having obsorved enough energy from the sun to sustain them.  I do not vouche for the credibility of these individuals... but I do feel that it offers some food for thought...