Megan Fox and Kumail Nanjiani struggle with body dysmorphia — and they're not alone. Here's what it means.

Several celebrities have spoken out recently about struggling with a mental health disorder that makes people obsess over their bodies.

Actor Kumail Nanjiani recently talked to Vulture about getting incredibly muscular for his role as a superhero in Eternals, and how the aftermath made him think constantly about his body. "The way I look has been way too important to me," Nanjiani said. He ended up seeing a therapist regularly, learning that he had developed body dysmorphia at some point, which made him think he looked different from the way the world perceived him. Nanjiani said that, at one point, he fixated on so-called problem areas with his body to the point where he would spend hours scrolling through photos of bodybuilders for inspiration.

"I know exactly what I weigh every day, and if I could change something, I would love to not have to think about that," he said.

Ninjiani's interview was released right around the same time as a British GQ cover story with Megan Fox and her boyfriend, Machine Gun Kelly. In that interview, the 35-year-old actress also said that she has body dysmorphia. "I have a lot of deep insecurities," she explained. "We may look at somebody and think, 'That person's so beautiful. Their life must be so easy.' They most likely don't feel that way about themselves."

Body dysmorphic disorder (BDD) is a mental health issue in which someone obsesses over one or more perceived flaws in their appearance that are usually seen as minor or aren't even noticed by others, according to the Mayo Clinic. People with BDD can feel so ashamed and embarrassed about their perceived imperfections that they may even avoid certain social situations as a result.

"Some characteristic activities of someone with body dysmorphia include compulsively checking oneself in the mirror, avoiding social situations or taking photographs with others and always comparing oneself with others," Dr. Uma Naidoo, a psychiatrist and author of This Is Your Brain on Food, told Yahoo Life. "Other red flags may include wearing clothes to hide their body, constantly exercising, dieting or grooming oneself or having an opinion of one's own appearance that far contradicts what most others, especially trusted friends and family, perceive."

"People with body dysmorphia do not really see themselves as the world sees them," Thea Gallagher, a Philadelphia-area psychologist and co-host of the Mind in View podcast, told Yahoo Life. "They tend to use a lot of negative language about their body and compare themselves a lot to others in a way that can be problematic."

People with BDD may do things like work out excessively, analyze their bodies in their mirror for hours or seek out plastic surgeons to try to change something about their bodies that they find undesirable, Gallagher said. She's quick to point out, though, that wanting plastic surgery doesn't automatically mean you have BDD. "You need to think about how negative the language is that you're using to speak to yourself about your shape and weight, and how much time you're spending thinking about a particular body part or parts," she said.

Body dysmorphic disorder is more than feeling insecure about a particular body part or area, clinical psychologist John Mayer, author of Family Fit: Find Your Balance in Life, told Yahoo Life. BDD "is a diagnosable mental disorder characterized by a preoccupation with a perceived body deficit or flaw that is not perceived by others. Essentially it is not real," he said, noting that the disorder "causes an impairment in the person's functioning in social, work and personal areas of their life."

Simply feeling self-conscious about your body "has none of the seriousness of the disorder or intensity and is extremely common in the U.S.," Mayer adds.

Body image researcher David Frederick, an assistant professor of psychology at Chapman University, agreed. "There are many people who are unhappy with their appearance," he told Yahoo Life. He points to a recent national study he published in the journal Body Image, in which his team of researchers found that 27 percent of men and 39 percent of women are dissatisfied overall with their appearance, and 36 percent of men and 49 percent of women are, to some degree, dissatisfied with their weight.

"Body dysmorphia is a particularly severe manifestation of body dissatisfaction, affecting about 1 to 2 percent of the population," Frederick said. "People with body dysmorphia become excessively preoccupied with a perceived flaw in their appearance, and it creates substantial distress that it impairs their ability to do their jobs or to be social with others."

People with BDD "may also feel that others are judging them or mocking them due to their appearance," Adelle Cadieux, psychologist at the Helen DeVos Children’s Hospital, told Yahoo Life. While many people may have some minor symptoms of body dysmorphia from time to time, "someone with body dysmorphia has behaviors and thoughts that are persistent and ongoing and take up a significant amount of time each day that it is impacting their ability to function," Cadieux says.

One thing Gallagher likes to do in therapy is to have patients make a pie chart of how much time they think people should be focused on things like friends, family, work, leisure activities and their shape and weight, and then have them do a realistic assessment of how much time they spend on those things. "Yes, it's good to exercise and be healthy, but to what extent are you focusing on those things and how badly do you feel about it?"

Gallagher pointed out that we live in an image-conscious society, and it can be difficult to feel positive about your body if you're constantly seeing digitally altered images on social media. If you suspect that you have BDD, she suggests reaching out to a mental health professional for help. "There are treatments, including cognitive behavioral therapy and pharmacological treatments," she said. In therapy, a mental health provider will help work with you to learn how to challenge your own negative thoughts about your body and learn tricks you can do to reduce the urge to constantly check your appearance, Gallagher explained.

Medications like selective serotonin reuptake inhibitors (SSRIs) can also help control negative thoughts and behaviors, she says.

If someone you care about is showing symptoms of BDD, there are ways you can help too. "It may help to listen to their concerns in an empathetic and nonjudgmental way," Megan Mikhail, a psychology researcher at Michigan State University, told Yahoo Life. "Rather than commenting directly on a person's body, even to offer reassurance, it may help to acknowledge their emotions." Mikhail suggests saying something like, "I can see that this is really upsetting for you to think about." Then, if you feel comfortable, Mikhail said, it's a good idea to encourage them to seek help from a therapist.

It's also possible to spend a lot of time thinking negatively about your body or a certain body part without meeting the clinical criteria for BDD. If you think this describes you, Gallagher recommends taking steps like talking with friends about your body concerns, curating whom you follow on Instagram to weed out posts that tend to feature unrealistic or digitally altered bodies and working overall "to not have your happiness be based on your appearance."

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