Knightley 'Doesn't Mind' Going Topless

Keira Knightley has been battling eating disorder rumors since her Love Actually days, but that didn't stop the Anna Karenina star from posing topless for Allure magazine.

"I'm quite rigorous about what gets exposed. No bottom half!" Knightley says of her nudity rules. "I don't mind exposing my t*ts because they're so small -- people really aren't that interested."

RELATED: How Does Keira Choose Her Sexy Roles?

She adds, "For King Arthur, for a poster, they gave me these really strange droopy t*ts. I thought, 'Well, if you're going to make me fantasy breasts, at least make perky breasts.'"

So, how much skin is too much skin for this British beauty? "I think it's much easier as you get older," the 27-year-old actress admits. "You can say, 'No.' 'Yes.' 'No.'"

RELATED: Inside the Anna Karenina Wardrobe

As for the criticism about her small frame, Knightley confesses that the eating disorder gossip does bother her. "The anorexic stuff -- all of that -- it's always going to have an impact, so I think it did hit pretty hard. Because you go, 'Oh, maybe that's right!' I knew I wasn't anorexic, but maybe my body is somehow not right. Or my face is not right. Or the way I speak is not right. When you're going through a period where you're really getting a lot of criticism, you go, 'Maybe all this is right! You just kind of want to hide it all.'"

The acclaimed actress will take on yet another period piece when Anna Karenina hits theaters Friday, Nov. 16.