Camila Mendes on Dealing with an Eating Disorder During Riverdale Season 1: 'I Was So Insecure'

Rob Latour/Shutterstock

Camila Mendes is getting real about dealing with an eating disorder, which she says hit a peak during the first season of The CW's Riverdale.

Speaking on Thursday's episode of the Going Mental podcast, the 28-year-old actress revealed to host Eileen Kelly that she'd gone back and forth dealing with body image issues since childhood. However, she said, it was during the filming of the series's debut season that her insecurities reached new heights.

"I would watch every episode and be like, 'Oh my God, my stomach there…' " she said. "I was, like, so insecure, and it really fueled my eating disorder."

RELATED: Camila Mendes Says She 'Started Having Panic Attacks' While Filming Riverdale amid COVID Pandemic

"When you're in your early 20s, like, your body is fluctuating...my body hadn't settled into itself yet," she added. "I was looking at myself, taking myself apart. My stomach, you know, my arms, my chin, anything — I would obsess over."

Mendes noted that the preoccupation with picking her appearance apart even interfered with her work as a whole. "It kind of got in the way of my acting because when I was acting on camera … it really f---s with your process," she said.

She also revealed that she sought the help of a nutritionist to help her get over her fears of certain foods, such as bread.

RELATED VIDEO: 'Riverdale' Star Casey Cott Marries Nichola Basara Before Costars and Friends

"I was really afraid of eating carbs, and what would happen is I would avoid it for a long period of time, and then I would binge and eat a bunch and then purge," she recalled. "So it was this, like, terrible cycle. She helped me overcome that by reintroducing bread into my life to be like, 'See, it's not going to kill you.' "

Mendes additionally brought up some triggers that set her back in her recovery. Hearing the phrase "you look so good" following weight loss was a particular hurdle.

"When I don't hear that, I think I look terrible," she confessed. "When no one's commenting on how thin I look."

RELATED: Riverdale's Camila Mendes Says Bond with Lili Reinhart, Madelaine Petsch Grew After Their Breakups

Mendes has been previously open about her eating disordered behavior, telling SHAPE in 2018, "I realized that I have this platform, and young women and men who look up to me, and there is a tremendous power to do something positive with it."

Despite her experiences grappling with self-image, however, Mendes said Riverdale has worked to force her to confront her own experiences to bring her emotionally complex character of Veronica Lodge to life.

"It's hard because sometimes you reach into those deep dark places of your past or your present in order to play that emotion authentically," she said last year. "But then you find yourself, once they call 'cut,' still stuck in that mindset. It's like you opened a wound, and now you have to see it through."

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

She continued, "I've had moments where the scene is over, but I can't stop crying. And I have to walk out of the room for a few minutes to catch my breath and compose myself and then come back. Because that can be dangerous, to pull from personal experience."