Actors Who Went Through Extreme Body Transformation For a Role

 Christian Bale, The Machinist

In The Machinist (2004), Christian Bale plays the role of Trevor Reznik, a machinist with severe insomnia. The lack of sleep leads to severe weight loss, so Reznik becomes extremely thin. To be fit for the character Bale needed to look drastically thin, so he had to lose a lot of weight. He went from from 173 pounds to 110 pounds. To lose these 63 pounds, the actor followed a draconian diet: for almost four months he ate only one can of tuna fish and one apple per day.