No. It's not absolute fasting, although I do that some times. I've been doing alternate-day fasting or a 3/5 diet, for around 6-8 months at a time, for the last several years because it makes me feel better.

There was a great program on the BBC[1] about "fasting-like diets", which generally consist of extreme caloric restriction for some time -- where what counts as "extreme" and "some time" varies from programme to programme -- and when it got to Michael's own experiments with fasting, the description of the feelings are what encouraged me to give it a try.

[1]: http://www.dailymotion.com/video/xvdbtt_eat-fast-live-longer...