'The Fighter' and 'Black Swan' seem like strange bedfellows, but they have more in common than it initially seems. Respective stars Christian Bale and Natalie Portman are gathering plenty of critical attention for their strong performances, as well as the stunning changes both made to their bodies to fit their roles. However, while this is practically par for the course for Bale, Portman is much more the subject of concern and criticism for her performance.

For 'The Fighter,' Christian Bale dropped an alarming amount of weight to play former boxer Dicky Eklund -- not so he could be in top-notch shape for sparring but because Eklund was addicted to crack. Bale has modified his body this way in the past in both directions -- in 'The Machinist,' he looked even more skeletal, having dropped over 60 pounds for the role, and then the actor bounced back almost immediately for 'Batman Begins,' where he fills out every inch of his bat-suit with rippling muscle.

On the other end of the scale, so to speak, Natalie Portman also subjected herself to rigorous training and weight loss to play prima ballerina Nina Sayers in 'Black Swan.' Portman, a former dancer, went back to the barre with a vengeance for this role, which probably will pay off in an Oscar nomination at the very least. Both Portman and costar Mila Kunis lost 20 pounds off their petite frames to play ballerinas, and Portman put in hours of ballet training on top of other exercise regimens and eventually the choreography for the film's dance scenes as well to perfect her performance.

Perfect is the key word here; Nina's desire to be perfect warps her entire world; it's also one of the things standing in her way when it comes to embodying the more sensual Black Swan, according to the ballet director ballet director Thomas Leroy (Vincent Cassel). Her bulimia and self-mutilation are established at the beginning of the film, as is her claustrophobic, boundary-less relationship with her mother, and under the pressure of her new role, Nina's questionable mental state crumbles with a quickness.

The real horror behind the beauty of ballet -- disfigured, bloody toes; ruined joints; disordered eating; lives given over to demanding teachers and endless rehearsals -- are ripe for the basis of a horror movie, which is, after all, what 'Black Swan' is. Nina is just a few grand plies away from David Cronenberg's car 'Crash' set. The marketing team at Fox Searchlight created an innovative and equally creepy campaign for the movie, with a Twitter account for Nina Sayers who "writes" things like, "I can feel the evil force pulling me. It's out of my control..." and the website I Just Want to be Perfect, as well as swag bags that include scissors and nail files (you can imagine how Nina abuses those implements in the movie). Many sports require unbelievable commitment from professionals, but few put such a spotlight on the intersection of body image, perfection, and stunted sexuality as ballet does; although 'Black Swan' cranks it up to ten, there's no denying that the terror it effects, especially on its female viewers, is because it's based in that reality.

Portman told NBC New York, "We were probably doing eight hours a day... and the physical discipline of it really helped for the emotional side of the character because you get the sense of the sort of monastic lifestyle of only working out that is a ballet dancer's life. You don't drink. You don't go out with your friends. You don't have much food. You are constantly putting your body through extreme pain and you really get that understanding of the self-flagellation of a ballet dancer."

Writers at sites like Jezebel and Crushable have taken issue with the language surrounding the training and performances of Portman and Kunis. Lauri Apple at Jezebel writes, "Portman had to do so much to her body to create her performance, so the line separating real-life and work became blurred. She had to pretty much live the part of her character in certain key respects. And now it seems like people are celebrating that fact, when instead they should probably be celebrating that she didn't suffer any apparent physical harm. Because BREAKING: when women undereat and overexercise, harm happens." Meanwhile, Meghan Keane at Crushable notes, "It's clear that Nina's story is a horror tale, but there's definitely a gray area of this film that heightens the depravity: and that's the fact that it both condemns and thrives on a very unhealthy approach to eating."

On the other hand, Christian Bale has been praised for the same level of discipline and uses language that indicates an even deeper sort of masochism in his method. He told the New York Times that his weight loss for 'The Machinist' required "a commitment level which I discovered I greatly enjoyed" and "I needed that... I'd felt a real staleness in the work and that rejuvenated me."

It would be impossible to interview people involved with 'The Fighter' or 'Black Swan' and not mention these physical transformations. However, the language surrounding how Portman and Kunis lost weight is more salacious and girl-talky. The title of the NBC New York interview I linked above is "Natalie Portman & Mila Kunis Confess: We Pigged Out After Ballerina Film Wrapped." The two actresses indulged the interviewer with tidbits about what they ate as soon as filming was over, describing pasta and In-and-Out burgers and the like. Similarly, Bale's costar in 'The Machinist,' Jennifer Jason Leigh, told People, "When [Bale] started to eat again, we warned him, 'Start slow. Eat poached eggs and raw foods... We watched in horror as he started with donuts.'" However, the title of the article isn't "Christian Bale Pigs Out" but "5 Things You Gotta Know About Christian Bale."

No one will look at Bale's emaciated figure onscreen and want to emulate him. Plenty of women already want to emulate Kunis and Portman, and some might even aspire to balletic proportions. (ELLE has posted a 'Black Swan' workout.) Kunis has been more blunt about the process; in her interview with Nylon (via PopEater), she said she looked like "Gollum," later telling E! Online, "I could see why this industry is so f--ked up, because at 95 pounds, I would literally look at myself in the mirror and I was like, Oh my God!... I had no shape, no boobs, no ass... All you saw was bone. I was like, This looks gross." Then she added, "In real life, it looked disgusting... But in photographs and on film, it looked amazing."

Bale doesn't look at all attractive in 'The Fighter,' even when his character is sober, and yet even when they're both under 100 pounds, Kunis and Portman both look stunning. At the same time, I find myself wary of sounding some sort of alarm over 'Black Swan' and not over 'The Fighter.' Although the context is different, to presume that the effects of 'Black Swan' on its cast or its viewers is more dangerous or irresponsible than 'The Fighter' implies that female viewers or actors are somehow less capable of separating film from reality or otherwise taking care of themselves.

Kunis also told E! Online, "My mom freaked out... Everybody started panicking. She was like, 'You have to promise me this isn't going to affect you.' I was like, 'I promise it won't, but it might take me a little time to be OK with having a little more fat on me.'" That's a statement that saddens and disturbs me, but it doesn't shock me, because disordered eating is an addictive behavior; actors are definitely playing with fire when they do these sorts of roles, both physically and mentally. But how come no one is quite as concerned about Christian Bale's mental or physical health after 'The Fighter?'

What's your take on the matter? Talk back in the comments!

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