Keira Knightley Keira Knightley

Keira Knightley says that being called anorexic over the years has taken a toll.

"The anorexic stuff — It's always going to have an impact, so I think it did hit pretty hard," the 27-year-old actress told Allure magazine in the December issue, according to E! Online. "Because you go, oh, maybe that's right! I knew I wasn't anorexic, but maybe my body is somehow not right." (Knightley won nearly $6,000 in libel damages after suing Daily Mail for saying that she suffered from anorexia in 2007.)

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Although Knightley says that she's comfortable with her thin frame, one thing she's not OK with is the way her body is PhotoShopped on movie posters. "They always pencil in my boobs," the actress tells Allure magazine. "I was only angry when they were really droopy ... For King Arthur, for a poster, they gave me these really strange, droopy t--s. I thought, well if you're going to make me fantasy breasts, at least make perky breasts."

Although Knightley, 27, appears on the cover and in the magazine in various states of undress, she says has limits for her roles. "I'm quite rigorous about what gets exposed," she said. "No bottom half! I don't mind exposing my t--s because they're so small — people really aren't that interested!"

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But, she adds, she sometimes finds her sexual exposure confusing to her morals: "I am a feminist, but I clearly objectify myself — so that right there is a total contradiction to feminist principles."

Read the full interview in Allure's December issue.