Mila Kunis Says She Barely Ate During Prep for ‘Black Swan’ Role

Mila Kunis is opening up about her grueling preparation for her role in Black Swan.

Speaking with Vogue in a new interview to mark the 2010 film’s 15th anniversary, the actress — who was joined by costar Natalie Portman and director Darren Aronofsky — shared how she transformed herself to portray a professional ballerina on-screen.

“My prep was a lot of dancing and very little eating — which I know you’re not supposed to say, but it’s the truth. I drank a lot of broth and danced for 12 hours a day,” she told the outlet.

“We were only supposed to have three months of prep before filming started, but we lost some financing, so that got extended to six months while Darren tried to find money,” Kunis, 42, continued. “It sucked for Darren, but Nat and I were so happy because we had three extra months to dance.”

The Luckiest Girl Alive star also recalled how she sustained painful injuries while filming the movie’s many dancing scenes.

“We would shoot those dancing scenes for hours, and I had bruises all over my ribs just from being lifted over and over again,” she told Vogue. “I also dislocated my shoulder pretty early in the production and thought I was completely screwed, but Darren sent me to an acupuncturist and I somehow came out totally fine.”

During the interview, Portman, 44, shared the surprising story of how Kunis came to be cast in the role of Lily, the seductive rival of Portman’s character, Nina.

“We had been friends for years, and I remember being at the Rose Bowl Flea Market with her, talking about this ballet movie I was making with Darren. Mila said, ‘I remember when I would take off my pointe shoes…’ and I was like, ‘Wait, you did ballet?’ I immediately called Darren and said there was this amazing actress with ballet experience who would be perfect for Lily,” she recalled to Vogue.

The only problem? Portman had oversold Kunis’ experience on pointe.

“I think I said, ‘I danced once,’ and that got twisted into me having taken pointe,” Kunis said, prompting Portman to reply, “I may have exaggerated on your behalf!”

The film, which had a modest budget of $13 million, went on to pull in nearly $330 million worldwide at the box office. Portman won the Best Actress Oscar for her mesmerizing performance.

Fans can catch the movie on the big screen once again for a limited time this month. On Aug. 21 and Aug. 24, a newly remastered version of Black Swan will be shown on IMAX screens across the country.

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Reflecting on the movie’s 15th anniversary, Portman told Vogue that seeing the final movie for the first time all those years ago was an “exhilarating” experience.

“I didn’t quite understand the tone of the movie while we were shooting, and was pretty surprised by what it ended up being. That first time watching it was shocking and exhilarating in a really wonderful way. I had no comprehension of the scope of Darren’s vision while we made it,” she said. “The success was incredible.”