The Observer Why it's playtime for Natalia Vodianova

She looks like the girl who has it all, but supermodel Natalia Vodianova is still haunted by the poverty of her early life. Now she plans to build 500 playgrounds in her native Russia

Although it's 12 years since she left Russia, Natalia Vodianova still gets homesick, especially when she hears the language. "It's odd because I even think in English now – though I sometimes dream in Russian, depending on who's in the dream and what's going on. But Russia has made me who I am: romantic, generous and a little melancholic."

The 27-year-old model grew up in the grimly industrial city of Nizhny Novgorod, Russia, in the sort of poverty that saw her single mother hold down four jobs while Vodianova raised her two sisters, one of whom, Oksana, has cerebral palsy. She was spotted at 15 by a model scout and taught herself English in just three months. She moved to Paris at 17, and by 22 she was a British Vogue cover star, married to property magnate Justin Portman and happily settled in the UK with their first-born, Lucas (who's since been joined by siblings Neva and Viktor). At this point, when most of us would have settled back to enjoy life's good fortune, Vodianova set up her own charity.

Unlike celebrities who blunder good-naturedly into complex political situations or try to solve global warming with a charity single, Vodianova's Naked Heart Foundation has a simple and personal goal. Founded in response to the tragic Beslan school siege in 2004, the charity provides playgrounds for Russian children: 39 have been built so far, and the target is 500. "I see the importance of play in my own children and the lack of it in me," Vodianova says. She estimates that, due to her family situation, her own childhood ended when she was six. "I would have loved somewhere to go when I was a little girl, somewhere I felt secure and that made me feel like a child. We adults have worries, but we forget that the little ones have them, too."

While Vodianova understands the plight of poor Russian children, life on the fashion circuit means she also knows how to get rich people to help them. She's one of the models who truly deserves the prefix super. She's appeared in more than 175 catwalk shows and was ranked the seventh highest-earning model in the world by Forbes magazine last year. "It's funny, though, I'm like an actor – actors use so much emotion on screen that they're almost drained of them in real life. It's the same for me. I've never coloured my hair; I don't have a beauty routine."

She says the secret to good modelling is all in the eyes. "You can't just think you're a body in a dress. When you look at someone and their eyes are shining, you can see they're engaged in the present and you want to talk to them."

Bodies are important, though, and you can see Vodianova's – all of it – on the cover of the latest issue of Lovemagazine. "Ah, yes. They are very daring pictures – I was surprised, as I thought they'd be more censored – but they look good and I have nothing to be ashamed of. I look after my body and I love it."

At the moment, though, she's more interested in the Naked Heart Foundation than nakedness in general – specifically the latest Love Ball, a fundraiser which is to be held in London this Tuesday, co-hosted by Harpers Bazaar editor Lucy Yeomans, with a fairground theme dreamed up by artist Dinos Chapman, and a charity auction featuring a Jeff Koons artwork.

Not all her good work gets a positive reaction, though. "One of my close friends asked how much money I made from the foundation," she says. "Is she insane? That's not philanthropy, that's robbery! While most people are very supportive, some can be very cynical; they think I'm doing it to raise my profile – though why would I need to do that?" Which is a very fair question, coming from someone whose modelling contracts with Calvin Klein, Louis Vuitton and L'Oréal have made her not only a millionaire (she earned £3.5m last year) but also one of the most recognisable faces on the planet.

But if you think she sounds a bit earnest, she really isn't. One of her many accomplishments: "I can flick and catch 52 beer mats with one hand. How did I learn to do that? Drinking beer, of course."