2. Christian Bale
In order to play an industrial worker suffering from chronic insomnia in The Machinist, Christian Bale lost more than 60 pounds.
Producers forbade him from losing the additional 30 pounds Bale thought was necessary to do the role justice due to health concerns.
This shows incredible commitment that later resulted in his “sudden” rise in Hollywood. If you saw the movie you can remember just how skinny he was.