Good evening, you're about to meet a woman battling a dangerous obsession, it is one 8 million Americans share, many suffering in silence, for them, food is the enemy. And if you think overcoming an... See More
Good evening, you're about to meet a woman battling a dangerous obsession, it is one 8 million Americans share, many suffering in silence, for them, food is the enemy. And if you think overcoming an eating disorder is a matter of willpower then this young woman's journey may shock you. To me, this will be really cute. Reporter: Jenna loves fashion, she has style and grace, a seemingly secure and confident young woman. But 22-year-old Jenna has a dark secret. I do a lot of emotional eating. I use it as a crutch. To feel better, almost like a drug. Reporter: She desperately wants to be thin, and idolizes the bodies of stars like Rihanna and beyonce. Black women are shown to be confident about their curves, but at 5'9" and 235 pounds, she says she feels ugly and heavy. Feelings that push her to extremes. I eat, not even joking like a half gallon of ice cream. Reporter: Binge eating is a common disorder that affects black women but it is rarely talked about. I am heading out to class right now. Reporter: A few months ago we gave her a camera to document her struggle. I wish my stomach was flat, I wish my thighs were slimmer. Every time I use the scale to lose weight I become very obsessive about the number, and that is when I end up -- that is when I end up purging. Reporter: She succumbs to frequent eat iing sprees, and from time to time she forces herself to throw up. How long do these binges last? Is it hours, days? Sometimes it is months, sometimes it is only a week or a few days, or maybe just a couple of hours. Reporter: What does it mean? What does it look like? Eating when I'm not even hungry, I don't have a candy bar, I'll have like three candy bars and like a half a gallon of ice cream. There is no point where I'm like I need to stop. Especially when I feel like I'm in that dark place. Reporter: It is aifficult topic to talk about in any family, but often in black families eating disorders are not seen as a real issue. I don't understand why she can't see she is beautiful, she is a beautiful black woman. Reporter: We visited Jenna at home on the south side of Chicago, she lives with her parents but somehow she has managed to keep her secret from her whole family. And she keeps everything inside, even though I ask, she doesn't tell me. I don't really deal with it, you know, like my mom said. Reporter: But today, Jenna has finally worked up the courage to tell her mom. I mean, that is not something that I do often, but when I feel really bad and I'm eating a lot that I know I should not. I guess I'm in an emotional state so I get rid of it, pretend like I didn't eat it. I'm learning something here too, today, because I understand it. We've all done it. I have done it. You know you have used food to soothe yourself or make yourself feel better. You know you have eaten way more than you should and you want to get it out. I have done it. Reporter: Because women of color don't talk about it doctors often ignore the signs. There is this assumption that black women are expected to be overweight. That you know we like our curves. That it is not an issue. And unfortunately what happens if a black woman walks into an office and she is obese, obesity will be evaluated. They're not going to ask if you're depressed, do you use food to cope, do you feel like you're eating is out of control? Reporter: Black women often go undiagnosed and that makes the statistics inaccurate. Are you bulimic again? No. Reporter: From TV to music, the media often perpetuates the stereotype that black women embrace their curves. And Nicki Minaj discusses it in her song. Reporter: Even beyonce questions the standards in her musical video "Pretty hurts" the video sparked a social media conversation with fans asking, hash tag, what is pretty? It seems that the world's perception of black women is that they all want a big booty, black is beautiful, big is beautiful. Reporter: Do you think that is true? The noise we are fed? I think in media we still have a ways to go because whether what you see is on television, really is a thin or overweight black woman, is either the comedian. Reporter: The funny black women. I see some of you skinny Nervous. Y'all looking right here, baby, this is a Leg. We have insecurities just like every other woman, we may put on that act because we have to be the strong black woman, no, we have insecurities just like everybody else. And it gets hard because you have to sort of put on the face like oh, no, I'm fine. Reporter: So just tell me again why you like her figure. She has the ideal black woman body. Exactly. Reporter: For Jenna, images of curvy black women she sees on line and even in magazines often makes her feel even worse about her own body. What is that dark place for you? Just insecurity. Self-doubt. Just feeling hopeless like I wouldn't be able to achieve my goals. Reporter: Does the food give you -- does it help? It helps me feel better, but immediately afterwards I am in a worse place than I was before. I wish I could wear something like that. Reporter: Jenna has yet to seek therapy in part because she can't afford it, but for now she is hoping to get better on her own. For me, I don't really want their life or anything. I just want that for my life. Reporter: For "Nightline" ABC news, Chicago.
This transcript has been automatically generated and may not be 100% accurate.