New Year, New You in 2014

Hollywood's Weight-Loss Winners

See which stars transformed themselves – Jessica Simpson! Jennie Garth! – with a whole new look and attitude

KELLY CLARKSON

Along with a new man, Clarkson got a new look in 2012. "I do cardio. I run. I strength-train using my own body weight," she told Redbook, adding, "[I try] to be healthy and happy."