Natalie Portman Is Back on the Carbs After Black Swan

Natalie Portman had to change her eating habits significantly to play a prima ballerina in Black Swan, but once filming ended, so did all the dieting.

"It was just pasta and bread and pizza all the time," Portman told PEOPLE of her post-Swan diet at the film's Tuesday premiere at New York's Ziegfeld Theatre.

While filming the psychological thriller, though, a change of eating habits was key. "It wasn't really giving up [food]," Portman, 29, says. "It was just smaller portions ... It was more quantity than a particular thing.Another challenge: the grueling yearlong dance training it took to get into character.

"Working five to eight hours a day fo...