I watched it. I have to say, interesting, but I do take some of it with a pinch of salt.
Take for instance, when they put a healthy person on the 'bad' diet. They always feel c**p, but then don't we when we first give up caffeine, or go on to a VLCD?
They have the right idea though, but there's just bits that I think are a bit weird.
Sometimes I wish I wasn't so cynical, and I could just enjoy.........