The rapper, real name Curtis Jackson, said he lost the weight with a liquid diet and strict exercise regimen that lasted more than two months, People magazine reported Thursday.
He also removed his collection of tattoos for the role.
Besides "Things Fall Apart," due next year, 50 Cent is co-starring with Chace Crawford in the drama "Twelve." He also kicks off his U.S. tour Friday in Cleveland.
Celebrity Couples of 2014 [PHOTOS]