Dizzee Rascal is sitting on the edge of the bed in a West London hotel bedroom, sounding like a young man who can't quite believe how he's got this lucky, this spectacularly successful, this young. And then the 23-year-old bestselling hip-hop star lifts his T-shirt and I glimpse a pale grid of scars that mark the spot where, five years ago, he was stabbed in an attack that almost cost him his life.

We're here to discuss his latest single, Dean, which Rascal - Dizz to his friends, though his real name is Dylan Mills - has written in memory of a school friend, Dean Munroe, who, at 19, threw himself off a tower block in East London four years ago, leaving behind a girlfriend and baby. Rascal talks fast and with intensity, and it's clear, despite the bravado, and the man-to-man joshing about weed and girls, that the death of his friend affected him deeply; and he wants to do all he can to focus attention on the problem of suicide among young men. With three young men in Britain taking their lives every day, it's a message that could not be more timely.

Despite his youth, Rascal is already a big star. His debut album, Boy in Da Corner, scooped the Mercury Music Prize in 2003 from under the noses of Radiohead and Coldplay. But, as he speaks, it's clear that this success came against the odds: he lost his father when he was only 2 and grew up surrounded by gang-related violence in Bow, East London. And yet, as he opens up on religion, the counselling he had as a child, his relationship with his mother, and the help he derives from the spirituality of the late martial artist Bruce Lee, it feels increasingly unfair to tar him with this tired bad-boy cliché. Here, for all his macho front, is a young man struggling, in his words, to be “real”.

Hungry for a role model

When Rascal's father died, he found himself gravitating towards men he felt he could look up to. He acknowledges that being without a father made him hungry for male role models, and says that he has had a few mentors. “When I was younger I was really close to [Watford FC footballer] Daniel Shittu. He grew up in my area and was like my big brother at one point, when I was fighting and all that. I was really close to him. Because there were things I couldn't tell my mum, you know?”

His Ghanaian-born mother Priscilla, though, who raised him on her own, did the best she could for her rebellious son. He says: “I had issues as a kid. I was violent and disruptive. The way my mum helped was by finding me a different school every time I got kicked out, always fighting to keep me in the school system.” He certainly didn't make it easy for her, being expelled from four schools before, at Langden Park Comprehensive in Poplar, finally finding a subject he liked: music. As a 15-year-old, he was moonlighting as a DJ in local clubs, was signed by XL Recordings and, at the age of 16, released his first single, I Luv You.

His startling success at such a young age speaks of inner strength. Rascal says that he draws on religious faith. “I was raised in the Church and, yeah, I pray sometimes. But I talk to God in my own way, and my own time.”

For relaxation, he opts for “going to hot countries and jet-skiing, drinking nice alcohol with a nice pretty girl, you know? But I might go and sit with my friends in a council estate and smoke weed, too,” he adds, adroitly ducking my question about his current romantic life.Drink and drugs, though, he adds quickly, are in moderation. “I smoke a bit of weed for stress. But I'm not the kind of person who overdoes it. I don't go on three-day drug binges. I don't fall out of clubs drunk.”

Judging from the impressive six-pack he displays when he hoists his shirt he takes his fitness seriously. Specifically, martial arts and the jeet kune do of the late Bruce Lee, though he admits that with the pressures of his career “it's hard to keep everything up, so it ends up being a hobby, really”. Currently, it would seem that he has more time for Lee the writer. “He is more than a martial artist. He's a philosopher, a deep guy. I've been reading Lee's autobiography, Artist of Life and there's a lot of insight into the soul, the world, life in general. It's not overly intellectual, but it's the kind of deep that people don't always feel comfortable going on about around other people.”

Doing his bit for a suicide charity

When Rascal first heard about Munroe's suicide, he says, he was shocked: “It must have been super-rough for him to have killed himself. I still don't know quite what drove him to it. We have all been there, felt really low, back against the wall, as if the world is definitely against us.” Had he known how profoundly depressed his friend was, he'd have “tried to ask him about what was going on”. The problem with men, Rascal observes, is that confronted by emotional difficulties “they kind of feel that you need to hold sh*t in, suck it up, just firm it, get on with it. What a lot of young men don't realise is that if you've been through a lot of things you kind of need to talk. The more you bottle up, the more it'll beat you up”.

These are the themes of Dean, the proceeds of which Rascal is donating to the Campaign Against Living Miserably (CALM), a charity that works specifically with young men in danger of suicide. It is a mournful, measured song, tinged with anger and sadness.

Unlike some of Rascal's other work, which manages to combine comedy - “My name is Rascal, listen to my flow/ I socialise in Hackney or Bow/ I wear my trousers ridiculously low” - with thinly disguised menace - “We used to fight with the kids from the other estates/ Now eight millimetres settle debates” - Dean aches with longing and vulnerability, and regret that he could not have done more to help. “To this day I can't relate to how you must have felt inside. I can only get the impression it was horrible,” he sings. Rascal may speak movingly of the difficulty young men - in particular, young black men - often have in admitting their vulnerability, but it is a conflicted message, not least coming from a rap artist.

It's a genre, after all, that has long been associated with the bravado-filled, menacing world of gangs, guns and drugs. And Rascal's music has never exactly shied away from the connection, an impression further strengthened in July 2003 when he was pulled from his moped in the Cypriot resort of Ayia Napa and stabbed, allegedly by members of a rival rap group, just weeks before Boy in Da Corner won him the Mercury.

Saved from the street by his creativity

Rascal didn't seek revenge. Indeed, he seems to have surrounded himself with the kind of people whose first impulse has been to protect him, not to strike belligerent poses. After he was released from hospital, stitches in his chest and backside, his producer sensibly took him out of circulation for a while so he couldn't get caught up in recriminations.

It seems that this skill at finding the right mentor is not new. And yet, growing up in Bow, he was in gangs and not the only one of his peers to lack a father. “That's what the gang thing is about,” he says. “Roaming about in packs of boys up to no good. A lot of those boys come from single-parent homes, just trying to find their way. It's misguided; that ain't how to be a man. You're just causing havoc, but at the time it's what you feel.”

In the end, he believes that what saved him from ending up on the street - or, even, ending up in the kind of desperate straits that caused Dean to take his life - is his creativity. “Even when I was getting kicked out of school I still made music. I found a way to channel my energies into being creative instead of destructive.” And these days, faced with the kind of frustration that in the past might have triggered a violent outburst, he tries “not to be around anyone long enough to have a disagreement and, if I do, I just walk away. I just try to let it go”.

Dean by Dizzee Rascal is released on Monday. All profits will go to fund CALM's helpline, 0800 585858. Visit www.thecalmzone.net

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