11/14/2008 AT 11:00 AM EST
appears naked in her upcoming film The Reader
. She doesn't use a body double and disputes weight-loss claims. What's her secret?
"My mantra is 'keep it simple,' " the five-time Oscar nominee tells the U.K.'s Daily Mail
in a new interview, revealing that she cooks at home and she eats anything except pasta – "it gives me a stomach ache."
She's also a Pilates person!
"I have a mat and little hand weights and I do a stomach thing and a bum thing. It's very simple – you barely break into a sweat," she says of practicing to a DVD "on the living room carpet."
"Here's what's so great about it: no one's looking at you, no one's telling you what to do or work harder or anything like that," says Winslet, 33. "I know it seems slightly tragic but it's my way of exercising in a time-efficient way."
Winslet – who says she does not employ a trainer or a chef – adds: "My body's different. It has settled into what it is now. None of this different diets lark. I can't remember the last time I tried some new fad."
"Nobody is perfect. I just don't believe in perfection. But I do believe in saying, 'This is who I am and look at me not being perfect.' I'm proud of that."
So what does the mother of two, whose "boobs are worse for wear," try? "I do whatever I can just to stay healthy," she says. "I don't go to the gym. I mean, I go through phases where I think: 'Oh, I really should go and do a class.' "
Of the Vanity Fair
shoot, which sparked a flurry of digital retouching claims
, the actress says she was just in character. "I feel like I was playing the part and not me – it doesn't feel like me. It took six hours to set up the lighting and the hair and makeup, because I obviously don't look like that all the time."
Who's your Favorite Star Under 35? PEOPLE.com and the People's Choice Awards are counting your votes! Click here to vote now!RELATED ARTICLE:
2001: Kate promises to remain 'the curvy Kate that everybody knows' RELATED GALLERY:
Read about more curvaceous celebs on the covers of PEOPLE!