Natalie Portman has a lot on her plate right now, which is a big shift from when she was filming the highly acclaimed Black Swan, which has earned her a Golden Globe nomination for Best Actress and has received much Oscar buzz.

The 29-year-old actress might be preparing to show off a baby bump, following the announcement of her pregnancy and engagement to Black Swan choreographer Benjamin Millepied, but it wasn't always so. Portman recently opened up about what it took to shed 20 lbs. from her already slight 5' 3" frame.

"There were some nights that I literally thought I was going to die," Portman told Entertainment Weekly about the psychological strain of the thriller coupled with the pressure of attaining a skeletal appearance. The year-long dance training was brutal. "Working five to eight hours a day for a year … it's what real dancers live through," she told People. "It was an amazing experience, but definitely a difficult one." Thankfully, her fiance-to-be was patient and flexible on the choreography. "He knows how to change when things aren't working well. Sometimes I just couldn't do something. No matter how hard I worked, I couldn't do it. He would fix it to make it something that I could do."

Of course the petite actress had to change her eating habits to slim down so drastically. She had to exercise strict portion control and carb intake while playing the prima ballerina, which was "very challenging physically," she revealed to Access Hollywood at the movie's premiere. After filming wrapped and she was free to pile on the carbs again, Portman admitted, "I was like, pasta, pasta, pasta! No working out!" Her reaction "was pretty immediate. I was ready to leave the ballet life." She only had one minor concern. "I was like, 'Please don't let there be re-shoots for this [film] because I don't think I could get back into the costumes!'"

Black Swan director Darren Aronofsky testified to his leading lady's dedication, saying she "took [the role] very seriously. At a certain point I looked at [Natalie's] back, and she was so skinny and so cut – I was like 'Natalie, start eating.' I made sure she had a bunch of food in her trailer."

Speculation is surfacing over whether Portman's talked-about weight loss will give her a boost during awards season. The Golden Globes airs on January 16. You can also see a more filled-out Portman in the upcoming No Strings Attached with Ashton Kutcher, hitting theaters on January 21. —KIMBERLY STEELE

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