"When all that blew up, I felt terrible," the actress, 22, tells the British edition of Elle in its June issue.
"It appeared that I were promoting something when I absolutely was not. I am thin because that's what I am, and I was thinner at that point because of the work I do. Nothing else."
In January, when the photos were taken, Keira Knightley had just finished filming the final installment of the Pirates of the Caribbean trilogy, At World's End.
"I had lost weight," she says.
THG NOTE: Noooooooooo kidding.
"We were filming in searing temperatures and shooting fight scenes in which you were wearing a wetsuit underneath a load of corsets, fighting with heavy weights in the water. Can you imagine a more advanced cardio workout than that done hour after hour?"
In January, the Love Actually star sued Britain's Daily Mail tabloid for implying she lied about having anorexia.
"I was completely devastated by all that," she tells Elle about the anorexia rumors, adding that she even visited her doctor for advice on how to put on weight. "Whatever people say about my weight they are all wrong."
"He told me that for someone of my body type to get to a [European] size 12, I would have to eat a lot of sh!t food, stop exercising and drink loads," she says.
THG NOTE: In other words, become Britney Spears, circa 2004-2006.
"But I don't want to have to go 'round eating crap and being really unhealthy in order for people to stop having a go at me."
She's also learning to get past her own insecurities about her body. "I wish I had longer legs, but I haven't," says the porn comic babe. "What I have does its job. Ironically, I'm learning to become more happy with myself as a result of this."
"I can see myself in five years or whatever just giving the whole thing up. I made a decision recently that I want a life instead."