At the movie’s outset, Brittany’s problem isn’t that she’s unhappy with her weight specifically; she’s unhappy with her life. Brittany, played with compassion and wit by Jillian Bell, is a 27-year-old working at a low-paying, dead-end job at a theater. Her social life is a string of late nights and heavy drinking with her New York City roommate, a self-centered Instagram influencer. (Is there any other kind?)

Brittany is boisterous and outwardly cheerful, and friends tell her that she’s the funniest person they know. But Bell’s subtle cues—a flinch after her roommate’s callous comment, a flash of vulnerability in her eyes when a guy flirting with her at a bar turns lewd—let the audience know that Brittany’s humor is a form of self-defense. Like so many people who struggle with insecurities, Brittany cracks jokes at her own expense so that others don’t get there first.

Brittany’s weight emerges as a central plot point when she pays a visit to the doctor in an attempt to get an illicit Adderall prescription. Instead, the doctor declares that he’s worried about her BMI (an oft-criticized measure of health, for what it’s worth), as well as her high blood pressure and elevated resting heart rate. He instructs her to lose between 45 and 55 pounds. “That’s the weight of a Siberian husky,” Brittany notes wryly. “You want me to pull a medium-sized working dog off of my body.”

The movie is careful to have the doctor acknowledge that some people are fat because of genetics or thyroid issues, and that it’s possible to be both fat and healthy. Brittany, however, hasn’t been prioritizing nutrition and exercise. And so, with genuine, relatable fear—working out in public can be intimidating, particularly when you have a body that tends to be the target of scrutiny and criticism—Brittany starts jogging.

The allure of metamorphosis 

From the moment Brittany’s sneakers first touch the pavement, good things happen. She joins a running group, where she finds friends who actually care about her. They decide to train for the New York City marathon together, a goal that becomes increasingly meaningful to Brittany as a symbol of her ability to take control of her life. Since she’s got to wake up early for runs, she cuts back on the drinking and starts getting more sleep. And to earn more money for cross-training at the gym and other marathon-related expenses, Brittany gets a house-sitting gig—which leads her to a guy she’s first aggravated by and then, inevitably, attracted to, a directionless charmer named Jern (Utkarsh Ambudkar).

Exercise makes our heroine feel stronger, healthier, and more optimistic: So far, so uncontroversial. But Brittany also becomes visibly slimmer over the course of the film, which features a recurring motif in which her bare feet appear on a digital scale with numbers heading ever-closer to her goal weight. (Bell trained for a marathon in order to prepare for the role, and lost 40 pounds herself in the process; she wore prosthetics for Brittany’s earlier scenes.)

In some scenes, Brittany stares in a state of quiet, pleased shock at the image of herself in a top that’s now too large for her, stretching out the extra fabric. In others, she drops the laundry she’s holding to gaze at her mostly-naked body in the mirror, or sits in front of her laptop with her chin tilted to the side, taking selfies of her newly altered jawline.

These stand in stark contrast to shots of Brittany looking at herself at her heaviest. When she first tries to go for a run, Brittany catches a glimpse of her distorted reflection in a hot-dog cart, and is so repulsed that she turns back. In another scene, she flips through photographs of herself at a race, repelled by the sight of her double chin.

These moments give the audience insight into the depths of Brittany’s self-judgement. But because we’re seeing Brittany through her own unforgiving eyes, the camera also seems to urge us to scan Brittany’s body for flaws—to feel her disgust vicariously when she deems herself unattractive, and to feel a sense of victory when she looks in the mirror and takes satisfaction in the changes to her body.

Not only does this reinforce the biases that already prompt many people to struggle with physical and mental health issues, many women watching the film will see themselves more in the “before” version of Brittany than the “after” one, as NPR’s Mary Louise Kelly and New York Magazine’s Madison Malone Kircher point out. Since Brittany feels awful when she looks at the heavier version of herself, and since the movie never offers a corrective to her self-perception, plus-size women watching the film may feel that the movie expects them to experience that emotion when they look at themselves, too.

Body positivity in Brittany Runs a Marathon

Brittany Runs a Marathon, seemingly aware of how its central weight-loss plot could be perceived, tries to address the issue of fat phobia head-on. At some point, Brittany’s focus on changing her own body tilts over into judging the bodies of others, leading her to drunkenly humiliate a fat woman she meets at her brother-in-law’s party. Afterward, she sends the woman, Jasmine, flowers and a note of apology: “The truth is, I want what you have.” (Exactly what Jasmine has that Brittany wants is a bit undefined—an apparently loving and stable relationship? Confidence? Perhaps all of the above.)

The exchange provides the film with the opportunity to give Jasmine a monologue more in keeping with a newer, more enlightened way of thinking about body image. The character, played by Sarah Bolt, explains how she decided that, rather than waiting for her life to begin on some far-off day when she finally looked the way the world told her she ought to, she’d opted to be happy in the present. “And I am,” she says simply. In a related heart-to-heart, Brittany’s brother-in-law Demetrius tries to snap Brittany out of focusing so much on her body. “You changing your life was never about your weight, it was about you taking responsibility for yourself,” he says. And in another scene, Jern tells Brittany—trying to hint at his own attraction to her—that when it comes to sex and dating and body types, “people like all kinds of people.”

Jasmine, Demetrius, and Jern are talking sense, and it’s clear that the movie buys into the idea that weight loss alone won’t fix Brittany’s unhappiness. (“It’s important for us to see that Brittany has only worked on her outsides and not her insides,” Bell told NPR.)

What’s less clear is whether, within the film’s logic, Brittany could have transformed her life without losing weight—a realistic scenario, as Kircher points out, given that many runners don’t wind up dropping pounds. “There’s a whole community of proud, fat runners out there,” Kircher writes. “We’re not running to lose weight or fix something about ourselves.” The benefits that Brittany experiences when she starts running—a sense of empowerment, the satisfaction of working toward a goal, improved fitness, the joy of belonging to a supportive community—are all accessible to fat people, too.

The ethics of making a movie about weight loss

Is making a movie about a woman who wants to lose weight tantamount to capitulating to fat-shaming culture? Is it a betrayal of feminism to prefer the way you look at a certain size, and acknowledge that openly? Marisa Meltzer explored the subject for Elle back in 2013, discussing the guilt and sense of secrecy with which she’d undertaken a new diet and exercise regime. “I fear that instead of fighting for a world where all bodies are admired, I’m pandering, reshaping my body to make it acceptable to the world around me,” she wrote. Gabriella Paiella has also discussed the taboo around diet talk for New York Magazine, observing that while many women still want to change their bodies or maintain a certain weight, they’re hesitant to admit to it because “we worry about the possibility of offending others or losing our ‘feminist card.’”

On one hand, it’s quite reasonable to recognize that talking about diets and weight loss can hurt people who deal with eating disorders, bias, and body-image issues. As the writer who goes by the pseudonym Your Fat Friend explained in a Medium post about listening to thin people complain about their bodies: “I do not understand choosing to ignore the eating disorders you may be triggering, the trauma you may be causing, the harm you have been told you are causing.” Despite the inroads being made by fat-positivity activists like Tess Holliday or Naomi Watanabe, popular culture already provides incessant commentary about the importance of weight loss and the unacceptability of fat bodies. Talking about your own efforts to get to a smaller dress size can just seem like adding more unnecessary, unhelpful fuel to the fire.

But it’s also true that it’s not a moral crime to want to lose weight, whether for health reasons or for appearance-related ones. Meltzer asked Naomi Wolf, author of the foundational feminist text The Beauty Myth, if she was a bad feminist for dieting. While Wolf is no fan of diet culture, she was nonjudgmental about Meltzer’s choices. “I don’t think there’s anything wrong with taking care of your body,” Wolf said. “I just want to know you’re feeling beautiful and important at whatever weight you want.”

While there are always differences of opinion within any group, Wolf’s thinking is consistent with the general messages of the fat acceptance and body positivity movements. These are primarily focused on challenging the toxic cultural messages that suggest there’s an ideal body type, and helping people of every shape feel that they deserve love, happiness, and respect. Within the scope of these projects, there’s room to work on developing healthy self-esteem while also attempting to drop pounds. As Kelly deVos wrote for The New York Times: “I’ve come to feel that loving yourself and desiring to change yourself are two sentiments that should be able to peacefully coexist.”

Should is the key word here. But it’s already hard to love yourself when you’re a woman who’s been primed from birth to feel insecure about your appearance—let alone to thread the needle of loving your body while also trying to change your body and trying to push back against the unjust social conditions that led you to feel bad about your body in the first place.

Perhaps it’s too much to ask that one specific movie, about one specific protagonist, manage to strike this balance perfectly. Heck, perhaps it’s too much to ask of ourselves. Meltzer has also written that for some people, body neutrality—which involves learning to be less judgmental about your body without self-flagellating when you experience dissatisfaction with it—may be a more attainable goal than body positivity. Unfortunately, whatever our body size and shape, few women move through the world feeling entirely comfortable with their appearance, and it’s hardly shameful to acknowledge that.

The problem with Brittany Runs a Marathon, then, isn’t that it takes weight loss as its subject, but that it places so much emphasis on Brittany’s weight loss that it becomes impossible to separate her new size from her happy ending.

“We think that people lose weight, and then their life is just perfect,” Bell said of the problems with traditional weight-loss stories. But that’s pretty much exactly what happens to Brittany, too. By the film’s end, she’s got a new gig in her chosen field, advertising, which apparently allows her to afford the enviable apartment, packed with expensive-looking furniture, that she now shares with Jern. She finally runs the marathon, with her dedicated friends cheering her on; Jern wants to get married. The last shot of the movie is Brittany brushing him off, albeit jokingly, with a smile on her face, and heading out on a run.

She’s happy, and the audience is happy for her. But it seems likely that part of the reason she’s happy is because she’s changed her body to more closely adhere to mainstream beauty standards, which means she’s less likely to deal with the prejudice that many fat people face on a day to day basis. Losing weight literally made her life easier.

When NPR’s Kelly asked Bell what she wants women to take away from the film, Bell, who’s launched a body positivity campaign on Instagram, responded that she wants people to feel that they can be “happy and beautiful at any size.” The character she plays in the movie would probably agree with that statement—but for other people, of course; not for herself.

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