A friend of my sons went on a Chocolate Diet that he'd read about in a magazine.
He was allowed to drink water, tea & coffee but was allowed to
only eat chocolate for one week (he chose cadbury dairy milk)
then stopped for one week to eat normal food,
then went back on it for another week etc.. alternating eating chocolate every second week until he was happy with his weight loss.
After he had done it for 3 weeks, which is 2 weeks of chocolate eating, he had lost 5 kg He said he was allowed to eat day or night as much and whenever he wanted.
I thought wow I love chocolate I can do this!
So I set off to eat chocolate. Well after 2 days of merry munching, I gained 2 kilograms. I figured guys must have a good metabolism or something and I promptly quit that weird fad diet.