A woman who played Gwyneth Paltrow's body double in a comedy about physical beauty is opening up about the ugly side of her big-screen moment.

Ivy Snitzer, a then 20-year-old acting student, was cast as Paltrow's body double in the 2001 film "Shallow Hal," which starred Paltrow alongside Jack Black and Jason Alexander. In the film, Paltrow played Rosemary, a 300-pound woman whom Black's character falls in love with after being hypnotized to only see people's inner beauty.

Snitzer's role was having her body filmed for closeups of Rosemary's arms, torso and thighs, while Paltrow wore a fat suit for scenes that featured the character's face.

In an interview with the newsletter The Waiting Room, republished by The Guardian on Tuesday, Snitzer said she had a positive experience working on the film despite its weight-centric premise.

"At that point, if you saw someone obese in a movie, they were a villain," Snitzer told the British outlet. "Out of all of the fat people in the world that they could have hired for that job, they hired me, because of my personality. Before, I had to fight really hard to be seen as a personality and not just my size."

However, Snitzer said she didn't anticipate the scrutiny of her physical appearance that came with being part of a major film.

"It didn’t occur to me that the film would be seen by millions of people," Snitzer said. "It was like the worst parts about being fat were magnified. And no one was telling me I was funny."

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Snitzer, who struggled with disordered eating as a teen, said she continued to battle body image issues and strive for weight loss after the making of "Shallow Hal." "I hated my body the way I was supposed to," she said. "I ate a lot of salads. I had eating disorders that I was very proud of."

Snitzer's weight-loss journey reached a dangerous climax after undergoing gastric band surgery in 2003 at the recommendation of a doctor. Gastric band surgery is a type of bariatric surgery in which a silicone band is placed around a person's stomach to reduce its capacity and slow the passage of food, according to Cleveland Clinic.

But a complication in Snitzer's surgery led her to "technically starving to death." The band placed on Snitzer's stomach slipped, causing her to be unable to consume solid food for months.

"I was so thin you could see my teeth through my face, and my skin was all grey," Snitzer recalled. "I kind of alienated a lot of my friends. My mother was also dying; it was bleak. Humans shouldn’t have to experience how very bleak that particular time in my life was."

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Snitzer eventually began to rehabilitate her body after doctors performed a gastric bypass operation to remove part of her stomach. She said the experience helped curb some of her disordered eating. "Because I couldn't consume anything, my mindset became more about how much I could manage to consume, not how little," she said.

Looking back, Snitzer doesn't regret her work in "Shallow Hal," though she now acknowledges the impact the role's public reception had on her.

"I love that it's a cool thing I did one time," said Snitzer, adding that it’s "a fun story she tells over drinks." "It didn’t make me feel bad about myself. Until you know, other people started telling me I probably should have felt bad about myself."

If you or someone you know is struggling with body image or eating concerns, the National Eating Disorders Association's toll-free and confidential help line is available by phone or text at 1-800-931-2237 or by click-to-chat message at nationaleatingdisorders.org/helpline. For 24/7 crisis situations, text "NEDA" to 741-741.

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