For his new movie.
Quotet isn't uncommon for an actor to lose weight, gain weight, or otherwise alter their appearance for a movie. Tom Hank's lost weight for Castaway, Christian Bale lost weight for The Machinist, Matt Damon lost weight for Courage Under Fire, and 50 Cent lost weight for the upcoming, Things Fall Apart.
The difference, major actors in major roles.
50 Cent's drastic weightless could all be for nothing if Things Fall Apart doesn't get picked up. But then again, it could be the role that makes people take 50 Cent seriously as an actor.
Things Fall Apart is about a college football player who has cancer.
50 Cent's weight loss was achieved by walking three hours a day on a treadmill, and living off of a liquid diet for 9 weeks.
I hope 50 Cent's acting abilities in the movie, Things Fall Apart, can keep up with his dedication and desire to be a serious actor.