Amanda Seyfried's Raw Food Diet Secret

(CANVAS STAFF REPORTS) - Wonder what actresses such as "Mamma Mia" star Amanda Seyfried do to keep in such great shape? In the new issue of Esquire magazine Seyfried tells all.

"I'm on a raw-food diet," she revealed during an interview with the magazine, as she munched down on some tabbouleh. "It's intense. And sort of awful. Yesterday for lunch? Spinach. Just spinach and some seeds."

The blonde bombshell showed off her svelte physique when she posed in some revealing photos, wearing lingerie, in the April issue of Esquire.

And there isn't much left to the imagination in her new movie "Chloe," which has her baring all for a part as a call girl who is hired to seduce Julianne Moore's character's husband, played by Liam Neeson.

The scenes get so steamy, according to OK! Magazine , Seyfried didn't want her dad to attend the New York movie premiere on Tuesday.

"My mom's seen it," the 24-year-old said. "She came back for seconds [makes face]. But my sister [came to the premiere]. I did not let my dad come 'cause I'm not allowing him to see it. He's very proud of me, and he wanted to see some good work, but I can't."

According to Contactmusic.com Seyfried recently admitted that in addition to healthy eating, she works hard on her figure.

"If I didn't run and work out, there's no way I would be this thin," she said. "But I have to stay in shape because I'm an actress … If I'd been bigger, I don't think they would have cast me for 'Mamma Mia!'"

And the in-demand star hasn't ruled out turning to cosmetic surgery when she gets into her 30s and 40s – she told Contactmusic.com she may get a breast lift someday.

But for now, according to New York Magazine , Seyfried will enjoy her youth, continue to put on catsuits and look sexy.

"This is not acting, it's pretending," the actress told the magazine about her Esquire shoot. "I pretend I'm looking at a man who is looking right at me, a man who sees me as exceptionally clever and adventurous."