Five years ago, when Lily Allen was 16, she was not far from being a teenage waster with the in-built tendencies of a 50-year-old bum down the bookies.

‘I’d get up in the morning and didn’t have anything to do,’ she says, cheerily, in her measured way, ‘so I thought, “fuck it, might as well smoke a joint”. Then I’d sit on the bed and probably go to sleep for a couple more hours. Wake up. Neighbours. Listen to music in the afternoons: ragga, drum’n’bass, jungle. Sometimes I’d get The Racing Post in the morning and sit in my bed watching Channel 4 Racing smoking weed all day.

‘The thing is, I had loads of money ‘cos I’d had a record deal that came to a standstill and I took them to court so I had this bank account full of cash.’

Two months shy of her 22nd birthday and life is looking very different for Lily Allen. The incorrigible Londoner has spanned the globe, several times, performing in Europe, Japan, Australia and America since her ska-pop debut single ‘Smile’ took the UK No 1 spot in the summer of 2006. While other artists struggle for years to crack America, Allen’s album went straight into the US top 20. She recently appeared on Saturday Night Live with Drew Barrymore and is designing her own clothing line for New Look which will be stocked in 312 stores worldwide.

Whatever your opinion of the privately-educated singer with the chav image, it is not hard to see her commercial appeal. Here, at last, was brains, sarcasm, spectacular honesty and a permanently withering gob. Her carnival-kissed debut album, Alright, Still announced the most pithy chronicler of the world around her since the conquering Arctic Monkeys. She might have left the Brits empty-handed after being nominated for four awards but there’s no stopping the internationally beloved export, described by the New York Times as ‘a cross between Oasis in its trash-talking heyday and a beef-starting American rapper’.

Below the cursing controversies and the highly-opinionated, self-annihilating and profoundly chaotic image, Allen represents unwavering principles of old-school social justice. ‘If I was Prime Minister I would make it law that you can’t buy more than two properties,’ declares the Myspace pioneer. ‘People just buy more and more and rent them to students who get in more debt.’

We’re in her management office in west London, Allen in grey tracksuit civvies, fag in place, sprawled semi-horizontal on a spongy sofa much like she did, evidently, for most of her teenage years.
‘I feel sad for my generation,’ she laments. ‘There’s more to life than what we’re sold. I don’t believe anything that I read anymore and everything’s about branding and money and what you look like and impossible images and Kate Moss in a £3400 coat and it’s all bullshit. But I think that’s why it’s an exciting time, now, for music, because in youth culture we’re angry again. And that’s why bands like myself and the Arctic Monkeys are being listened to because we’re unhappy with the life that’s been built for us now. We’re not stupid.’

Allen was born into chaos in 1985, to mum Alison Owen, a punk turned film producer, and dad Keith Allen, actor, invincible libertine and best mates with Damien Hirst, Bez and Joe Strummer. ‘Joe really inspired me,’ says Allen. ‘We’d always be at Glastonbury together. I kind of made a speech at his wake saying, “I’m really gonna give this music thing a chance because I think Joe would want me to”. It’s really sad he died, before it all happened.’

Allen’s parents divorced when she was four and her mum later moved herself and the children in with her boyfriend, the comedian Harry Enfield, who was then at the peak of his fame. A loose-cannon growing up, Allen was expelled from 12 private schools, (‘I just didn’t wanna be at school, I wanted to be in London, having a laugh’). But she remained close to her dad despite bouts of profound embarrassment, most memorably when he recorded the Fat Les unofficial 1998 England World Cup theme-tune ‘Vindaloo’. ‘It was horrible!’ she wails of seeing her dad on Top of the Pops.

Post-school, aged 15, with no qualifications, the chemically-inclined Allen also discovered acid and ecstasy alongside her gift for acerbic songwriting and moved, temporarily, to Ibiza. There, she created musical contacts and sold E to her mates to make money so she could take MDMA. Back in Britain, she saw her beloved dance culture decline as the crack explosion took over.

Then, aged 19, her life literally fell apart. A long-gestating record deal with Warner Brothers fell through (‘my dream was gone’), and simultaneously her long-term boyfriend broke up with her. She was suicidal.

‘I took about 35 sleeping pills at my mum’s,’ she says, plainly, ‘and woke up in hospital. I’d just thought, “I don’t wanna be here tomorrow, when nothing else is ever gonna happen”. I was coming down off all the drugs I’d been taking for years and felt really alone. I remember thinking, “I just don’t have the energy anymore to . . . try”. I’d fallen in love, that was holding me together and once he left me I was like, “well this is just the end now”. But it triggered me to sort my life out.’

Today, Allen is ‘happy to be busy’ (it keeps her out of trouble), her chaotic past leaving her with a fundamental need for future stability, a not-so-far off emotional serenity where she can rear, naturally . . . championship chickens?

‘Championship chickens and grow my own vegetables,’ she nods. ‘All this is part of my life now but it won’t last forever. I want to enjoy it and try and gain some stability out of it. A house. So I can relax a bit in my late 20s and have a house in the country, quad bikes, bit of land, arrange flowers, keep pigs, a family. I’ve had enough noise and chaos. I think coming that close to giving up on life maybe you appreciate what life should really be about and it’s about love and children and that’s about it, y’know?’

Lily Allen, Carling Academy, Glasgow, Thu 8 Mar.