I actually found the documentary after it was mentioned on here somewhere but was wondering if you PB's have tried it and how it went?

In short it seems to be a matter of "fasting" for 2 days a week but where the fast consists of very low calories, rather than none at all. In the program he seems to do very well on around 600 calories a day during his fasting days.

Eat, Fast & Live Longer (BBC Horizon Documentary). 720p - YouTube

The 'potato diet' seemed to work OK for me for 2 or 3 days. This seems to be the same kind of thing but without the restriction to spud starches, instead just restricting calories.

Sez you lot?