Jessica Stam wanted to be a dentist, but fate (and fashion) intervened. Walking into the studio dressed in a sweatshirt, jeans and beaten-up trainers, she looks more like she is headed for the sixth-form common room than a fashion shoot, but then models these days are not the big personalities they once were. Naomi’s rages, Kate’s partying, Claudia’s babies, Cindy’s business empire — these women are celebrities. With Jessica Stam, one of the biggest girls in the new wave of models, it’s all about the looks.

In just two years, Stam (as she’s known) has become one of the most sought-after faces in the fashion world. Something about her fragile beauty seems to have struck a chord with the times: the strong women of the supermodel-obsessed 1990s have made way for gentler, more delicate faces.

It was the photographer Steven Meisel who made Stam who she is today. “He changed me,” she says. Before she met Meisel, Stam was just another 16-year-old model struggling to make ends meet in a flat share in New York. “The only place I had to myself was a top bunk and my suitcase.”

Eighteen years ago, Meisel discovered another Canadian schoolgirl, and his obsession turned her into one of the world’s most famous faces. Her name is Linda Evangelista. As soon as he set eyes on Stam, Meisel pounced, casting her in every ad campaign he did. He made her dye her hair often — at one point she was changing the colour every week — and the effect, as with Evangelista, was an intriguing chameleon-like quality.

Campaigns for Versace and Prada led to shoots for Italian and American Vogue, and suddenly Stam was a star. “I guess I’m his muse,” she says of her mentor, but the admiration clearly goes both ways. “He brings out the best in me. He’s inspired by works of art, old movies and paintings. If you work with him, you learn about the same things.” Not bad for a girl who grew up on a farm in the Canadian coastal town of Kincardine. “I didn’t know what modelling was,” she says in her soft, unassuming voice. Stam was raised in a God-fearing family alongside six boisterous brothers. The biggest influence on her young life was the church. “I had a religious upbringing,” she says, and describes how she sang in the choir and performed plays in front of the congregation.

One day, while returning from a trip to an amusement park, Stam was spotted in her local coffee shop by the model scout Michèle Miller. “Her hair was a disaster. She had a perm and had been dyeing it blonde. It was this awful yellowy orange,” Miller says. “Boys ignored me,” agrees Stam. “I never thought I was gorgeous.”

Surprisingly, Stam’s pious parents wholeheartedly approved of their daughter’s career choice. “They told me that this was my moment. They believe this opportunity was given to me and I have to go with it.”

In between cover shoots, catwalk shows and interviews, Stam studies by correspondence and is about to complete her Canadian high school education, but church has fallen by the wayside. “It was a good base to grow up on, but I’m not so religious any more,” she explains with a hint of guilt. Nevertheless, for a successful 18-year-old living alone in New York, she has so far resisted the sinful temptations of the industry. “There are tons of parties,” she says, “but I’m not really into it. You can have fun and not get caught up in drugs and alcohol.”

Despite her success, there’s nothing of the diva about her, and she displays a sage attitude to her chosen profession. “With modelling, you are judged on your looks. It’s easy to take that personally, but you have to realise that it’s only your appearance that’s being judged, not you as a whole. If you didn’t, you’d be destroyed.” Watch this face.

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