When anyone talks about Natalie Portman, much is made of her intelligence. After all, she is one of the few young actresses in Hollywood who not only went to college, but to Harvard no less. She's also renowned for being mature beyond her 26 years, an attitude honed via a childhood spent on grown-up movie sets.

When you meet Natalie, however, and hear her talk, you realise that reading a celebrity profile really gives you nothing more than a superficial snapshot. Individuals are, hopefully, more than a couple of witty and/or brow-furrowing soundbites.

Yes, she is articulate and well-spoken, informed and possessed of great beauty. But blink your eyes and look again and you'll see a kid, a girl in her mid-20s who looks 16, and who peppers her conversation about poverty in Africa and her charity work with dozens of "likes" and "whatevers".

It's refreshing that in the battle-hardened world of Tinseltown, where tweens have business managers, she hasn't forfeited her youth.

"It makes me feel better about being inside all day," she says, looking out the hotel window at the rain pelting down on New York City, before pondering the origins of the celebrity press junket, at which she is present to discuss her new movie, Mr. Magorium's Wonder Emporium.

"I thought it was such a wonderful thing to put out into the world," she says of the film. "It's so positive and in such a unique way."

Unique indeed. Natalie is the shop assistant at a magical toy shop run by the impossibly-old Dustin Hoffman, who finally decides to pass on the business, Willy Wonka-style, to her.

"I could really relate to the character too," she admits. "It was something I could really understand - that transition into adulthood."

Ah yes, the old passage from child actor to bona fide movie star. It's something that Natalie continues to grapple with, ever since making her debut aged 12 as a precocious wannabe hitwoman in Leon. Her role as Queen Amidala in the second Star Wars trilogy straddled the divide between youth and grown-up, but by semi-abandoning films and focusing on her studies, it seemed for a while that she wasn't interested in being a woman in Hollywood.

"I feel like there's two categories of women's roles. One is like, the muse, where it's literally the muse of some sort of artist, or you're the girl who makes the guy change," such as her recent flick Garden State, "or it's stripper/prostitutes," cue her role in film Closer. She laughs: "There are this many strippers and prostitutes? Because every script I get is one or the other."

It's no wonder she has expressed interests in pursuing other careers. She has a degree in psychology, speaks fluent Hebrew and her work has appeared in several scientific journals. Nonetheless, she now says it would be tough to give up acting and instead: "I try to pursue my interests as far as I can. I'm always taking a class in something."

Maybe she fancies herself as the new Angelina Jolie? Natalie works closely with the charity Finca and lights up when talking about her work with the organisation. Nonetheless, she is acutely aware of the potential danger of waxing lyrical about her extra-curricular passions.

"It's weird, because people criticise it a lot, when you have a cause or whatever," she explains. "'Oh yes, another celebrity with a cause.' But no-one's ever, like, 'Why does she keep talking about what designers she likes?' It's fully acceptable for a woman to talk for two pages of an article about, 'Buy this dress', but if you say, 'Go to this website and check out this charity, people are like, 'Oh, she thinks she's so great'."

Her comments make a lot more sense when you understand that she takes what she does and doesn't tell the public very seriously. For a start, Portman isn't even her real name, it's her grandmother's maiden name, taken on to protect her privacy at school.

Then there are the boyfriends, or at least the supposed ones. Natalie doesn't discuss who's she dating or dated, but names like Jake Gyllenhaal, Hayden Christensen and Gael Garcia Bernal have all come up.

"From a young age, my parents taught me not to talk about private stuff because as soon as you start putting it out there, it's like fair game," she says. "A lot of attention is focused on me for no good reason, it's the culture we live in."

Asked if she wants kids, seeing as how she's in a family movie, she abruptly says, "I would love to, I would love to," before making it pretty clear that the subject is done and dusted.

But as for why she hasn't fallen into the trap of Britney and co. (she once understudied for the troubled popstar while they were at a theatre camp as children), she says: "I think the press branded me as one thing. They branded me as the good kid. But none of us are all good or all bad. The kids who they're saying are party animals are not either.

"In some ways, it's a self-fulfilling prophecy - they follow you less, so they catch your mistakes less."

In other words, she's more than happy to continue as she is without making it into the pages of Heat. Next up is the period drama The Other Boleyn Girl, in which she plays doomed queen Anne Boleyn with Scarlett Johansson as her sister.

She's also currently shooting a remake of the Danish hit Brothers, alongside alleged former beau Gyllenhaal. Prestigious, arty projects for sure, but to float Natalie's boat it's got to be something she is passionate about, because since shooting a couple of Japanese adverts for shampoo and coffee when she was 19, money is the last thing on her mind.

"I really, really did not like it," she remembers. "I felt really bad, because I don't want to sell people things. I want to push things I believe in and I don't need more money.

"At the time, you're young and everyone's telling you you can make all this money and no-one will ever see it," she continues. "You're like, OK, I guess this is what everyone does. Brad Pitt does it!" She pauses, before laughing. "But if I do that for money, what else am I going to do for money?"