Not sure if anybody else caught this episode of the food programme on Radio 4 today but it touches on fasting - well it more than touches to be honest and some interesting perspectives. The religious elements are not for me though but here's the link, not sure for how long it will be available.
http://www.bbc.co.uk/programmes/b01rl1dl
http://www.bbc.co.uk/programmes/b01rl1dl