4. Jared Leto
Before playing murderer Mark David Chapman in the 2007 flick Chapter 27, Jared Leto put on a staggering 67 pounds. The actor appeared almost unrecognizable on the big screen.
He says that he ate almost everything he can get his hands on. As a secret ingredient he added chocolate that he consumed in every possible way.
It’s a shame that the movie didn’t fare well in the theaters, and generally receieved negative critics. It takes more than a weight loss to make a good movie.