None of us has any idea what we’re about to eat, until a paper plate appears on a long wooden table.

On it, we see three equal-size portions of General Tso’s chicken, white rice and broccoli. Next to it sits a small container of ice cream.

If we were somewhere else, a mystery meal might not seem a big deal. But we’re not. We’re not at a pop-up restaurant. We’re not at someone’s home. We’re on the 11th floor of an office building in Arlington on a Sunday, and for about half of the people in the room, unexpected foods can prove unsteadying, even terrifying.

Of the 13 people who will sit together on this night and share a meal, five have an eating disorder.

For them, this is not just dinner. It’s also therapy.

For the rest of us, it is a chance to see the hold that eating disorders can have on otherwise successful, smart people and to gain a better understanding of a psychological disorder that remains largely misunderstood, even as more people seek help for it.

“There are more people suffering than there are treatment options,” says Diana Gaydusek, a clinical psychologist who oversees the unique shared-meal program offered by Rock Recovery, a nonprofit that allows people to pay for its services on a sliding scale.

“We’ve had clients who have come in and have not eaten chips in 15 years, and then they have chips in group and are like, ‘Wow, that was not so bad,’ ” Gaydusek says. “We are exposing people to food that they would not be willing to try outside of the group.”

The goal, she says, is to get them comfortable enough with different meals so they don’t feel the need to avoid social situations or miss out on other aspects of their lives. One past participant in the program wouldn’t eat her own wedding cake, causing a fight with her groom. Others won’t walk into grocery stores.

That night, before we all scoop Chinese food onto our plates, Gaydusek asks people at the table to share how they’re feeling now that they know what’s on the menu.

A 25-year-old woman confesses that the ice cream is causing her some stress because she has already had ice cream once that week.

A 23-year-old woman says she has some “pretty bad memories of Chinese food” and is feeling “anxious.”

“My anxiety is through the roof because of the rice,” a 48-year-old woman says. “I will be present. I’m not going to guarantee how much I will eat, but I won’t check out.”

Usually, these meals are private. But this time, each of the women has brought a guest. Two women invited friends. One brought her girlfriend.

A 23-year-old came with a woman who has given her a home, makes meals for her and, in a motherly way, still wonders whether she’s doing not enough or too much.

The 48-year-old woman sits next to her husband. When his turn comes to share how he feels about the food, he pauses, takes a thoughtful breath and then admits how different this entire experience is for him.

“I’ve never psychoanalyzed food before,” he says. “Okay. Yeah, I like Chinese food.”

Everyone at the table laughs. In this way, there are moments of levity during the meal. People talk about planned vacations, work drama and new pets. The woman who took in the 23-year-old just bought her a therapy kitten. She passes around her cellphone to show everyone a photo.

Christie Dondero Bettwy, the executive director for Rock Recovery, says the organization has tripled its capacity to help people in the past few years. In its first seven years, it was mostly run by volunteers and could serve up to only 10 people each week. As a result, it had a year-long waitlist.

Bettwy recalls how frustrating and unfair it felt to tell people who needed support that they didn’t have space for them. She remembers one particularly painful call. When she tried to reach a woman to tell her that she was finally off the waitlist, Bettwy found out she had died by suicide.

“The problem is much bigger than anyone knows,” Bettwy says. When people find out about her work or her own past struggles with eating disorders, she says it is rare for them not to say: “Oh, me too.” Or “my sister,” or “my mom,” or “my best friend.”

Earlier this year, the group opened its first real office in Rosslyn, and between that space and a borrowed room at a D.C. church, it now serves 30 people a week. It also plans to start an adolescent program in the next few months. The goal, Bettwy says, is for the organization to have the ability to help 50 people a week by 2020, and eventually, to move into a townhouse with a real dining room.

The organization is Christian-based but has served men and women who practice different religions or who identify as gay or transgender. The sliding pay scale also allows people who wouldn’t otherwise have access to these services to afford them. The program has drawn college students, law enforcement officials, government workers, teachers, nurses and, in one case, a nun. The youngest person was 18. The oldest, 70.

“You can always sit with us,” reads a sign on the wall next to the table in the Rosslyn office.

The 25-year-old woman who worried about having ice cream twice in the same week sits with her back to the sign on that Sunday. She has brought with her a friend who has plans to soon get married and has asked her to serve as the maid of honor.

That night, the maid of honor doesn’t say much about the wedding, but when we talk the next day, she confesses that it will pose some challenges for her. She quickly ticks off three: She hates to be photographed. She dreads getting her dress altered. And then, of course, there is the wedding meal and dessert.

“There is an element of happiness and joyousness that I don’t think I’m fully going to get to experience because of this underlying worry and fear,” she says. “What people don’t realize is how much an eating disorder takes away from your life.”

At age 10, she went on her first diet after her pediatrician recommended she lose weight. By seventh grade, she says, she was struggling with depression and anxiety. By 10th grade, she was fasting for days at a time.

She says no one noticed she had an eating disorder in high school because she performed well in her classes, taking AP courses and earning scholarships. Similarly, while attending a college in the District, despite days in which she worked off more calories than she took in, she participated in Greek life, served as a resident assistant and led campus tours, all while graduating with two degrees in four years.

“I was that heavily involved person who would go to my room every night and feel like I was not going to make it through to the next day,” she says.

She describes the Rock Recovery program as providing her with a “sense of community,” “support” and “accountability.” That night of the shared meal, it also gave her something else. She says it allowed her best friend and her to talk about things they had “never really put words to.”

Toward the end of the night, Gaydusek asks everyone to write anonymous questions on index cards. She then reads each aloud.

How can I ask for support without crossing the line into being overbearing?

How do you know what type of support is needed?

As a friend, how do you balance being supportive and holding your friend accountable for their recovery?

“Is it okay to say, ‘I noticed this behavior?’ ” the bride-to-be asks. “Am I overstepping?”

“I don’t think it’s overstepping,” the maid of honor assures her. “It just shows you care.”

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