It's no secret that dramatic transformations help take an actor or actress' role to the next level when it comes to eyeing that Oscar.
In fact, many stars who have had to gain or lose a shocking amount of weight not only have nabbed a major nomination but also have taken home the beloved golden trophy—just look at Anne Hathaway in Les Misérables or Matthew McConaughey in Dallas Buyers Club. Yes, both of those stars lost a dramatic amount of weight for their respective movies, but actors have also been forced to either gain weight or build muscle to fit their characters' needs.
Michael B. Jordan worked out all day every day to gain the muscle he needed for Creed (which ended up being about 24 pounds). "I hated it. You know, at first you feel like s--t, you're hurting," he told Men's Fitness last year. "When things start getting a little easier, when you start lifting weight you never lifted before, when you start bench-pressing 225 pounds 10 times and it ain't nothing, and then you start giving hugs to girls and they're, like, feeling you up a little and you think, 'What's this?'—then it's, 'This is all right.'"
On the other hand, those having to lose weight probably have an even worse experience! Click through our gallery to see stars who have had to gain or lose weight for roles.