"Michael Mosley has set himself a truly ambitious goal: he wants to live longer, stay younger and lose weight in the bargain. And he wants to make as few changes to his life as possible along the way. He discovers the powerful new science behind the ancient idea of fasting, and he thinks he's found a way of doing it that still allows him to enjoy his food. Michael tests out the science of fasting on himself - with life-changing results."
I used to fast, when I was younger, as part of meditation exercises - it does have quite an effect, mentally. Still have a few books on it in my library.
Neat video, and an even neater concept.