Kim Kardashian Strips down to Her Underwear

'My reality is never going to be stick-skinny,' she says. 'I want to be fit for the long term. That’s why I’ve never even tried a cigarette in my life.

'I only started to drink last year when I turned 30. I occasionally have a Midori sour but I’m not a big drinker. I can have fun without it.'

And, unlike many other Los Angeles based stars, Kim isn't interested in being a size zero.

'It’s just a number. Your best measure is to look in the mirror. I always say you shouldn’t weigh yourself. I don’t even have a set of scales in my house.

'Personally, I’ve always loved the curvy look. Even when I was a little girl and all my friends would be like, "Oh, my god, your butt’s so big." And I’d say, "I love it."'

The star also acknowledges the role her famous sisters, Khloe and Kourtney and her family have played in giving her a healthy self body image.

'Having a bunch of sisters is like built-in best friends,' she says. 'We pump each other up and compliment one another.

'Me and my sisters all have such different body types.Khloé is super-tall, with great legs; Kourtney is tiny with a great stomach. We embrace the fact that no one is really alike.

'Our parents always made us feel like, "This is who we are, we’re all beautiful and this is exactly how we’re supposed to be." We never had any pressure to look different and I think that’s why we’re so confident about it today.'