Just read an article about Matthew Mcconaughey losing a ridiculous amount of weight for a film role - by just surviving on a very small amount of food a day.
I lost a stone in 2 weeks because it was an extremely hectic time and I just didn't get chance to eat properly.
Yet so many people say starving yourself doesn't make you thin, it slows down your metabolism and you won't lose any weight.
(I don't and would never recommend that anyone starves themselves to lose weight as its obviously not healthy)