Mind games

PAUL McKenna is giving me permission to flirt. I'm sitting on his couch, eyes closed, fingers pressed into my palms. It's all a bit excruciating. But already he's identified a conflict in my love life. One part of me wants to be more proactive; the other is making damn sure I don't get hurt again.

"Even though they are taking you in opposite directions, they both want the best for you," he advises. "Is it possible to unite these two guys? Place your palms against your chest, integrate it all at the unconscious level and don't be surprised by all the delightful changes that happen over the next two days." Blimey.

Multi-millionaire McKenna, 44, is the UK's top motivational coach. His clients include Geri Halliwell, Sophie Dahl and Robbie Williams. He helped David Walliams with the psychological aspects of his Channel swim. "I taught him a method of time distortion so it speeds up. I use it myself on plane journeys." But it's not just celebs: the chattering classes are queuing up to attend McKenna seminars, which sell out at £250 a time. Go to any dinner party and you're likely to meet someone he's helped quit smoking, lose weight or mend a broken heart.

McKenna insists he's not a guru or Svengali. But through neuro-linguistic programming (NLP) – the positive thinking and visualisation process that underpins his work – he says he can help us to reprogramme our brains. He compares it to rewiring a computer.

We meet at his Kensington Mews house. Interviewers always mention his silver Bentley, Brioni suits and gleaming Rolex. But today McKenna is in jeans and a simple sweater. He looks normal. But then, it seems he has undergone a Pauline conversion. Yes, he enjoys "nice toys", but now he's on a mission to heal people.

In a sense, January is McKenna month. We all yearn to change our lives after Christmas excess, and cannily he's just republished his 2005 bestseller I Can Make You Thin, with an extra chapter. So far, so obvious. But he's also determined to blow his old enemy – the diet industry – out of the water.

"I am on a quest to close down the hate-your-body industry," he declares. "Seventy-five per cent of people put on more weight than when they started. The reason half the country is overweight is because we've been dieting for the past 40 years. It's not just that diets don't work: they are the problem, cynically profiteering out of people's misery. I couldn't sleep at night knowing that, but these f***ers can. There is a better case for banning diets than banning smoking. Over 20 million people are putting themselves at risk because they're overweight."

McKenna claims his own weight-loss programme has a 71 per cent success rate (compared with nine per cent for diets). "There's an army of doctors right behind me who want to get this on the NHS." His system is simple. There are four golden rules. One: when you are hungry, eat. Two: eat what you want, not what you think you should. Three: eat consciously, and enjoy every mouthful. Four: when you think you are full, stop eating. The key is understanding the difference between "emotional hunger" – where we shovel in food because we feel bored or upset – and true physical hunger.

The funny thing is, McKenna has always been thin. So what's his motivation? "Most of my family is overweight. I'm contrary, I think. My parents would say: 'Eat up, there are starving kids in India', and I'd go, 'I can't see how me being overweight helps them.' The more someone tells me to do something, the more it makes me question it."

The dedication in his 2004 book Change Your Life in Seven Days reads: "To my parents, who gave me more than I realised". Was he a tricky son? "Oh, I don't doubt it, probably still am," he laughs. "We weren't that sort of family where we have big emotional outpourings, although my mum and dad have said some nice things to me in recent years." McKenna grew up, the elder of two sons, in Enfield, north London. His father was a builder, his mother a home economics teacher. He watched them lurch between times of plenty and times when they had to "batten down the hatches" – "I would see my parents' ups and downs and I thought it would be nice not to have that pressure."

From 11 he attended a Catholic school in London run by Jesuit priests who, he claims, specialised in guilt. He was told he was worthless (a school report said: "If he carries on like this, he'll never amount to anything"). When he published his first book he sent a copy to his old English teacher, with "F*** off" written inside. Childish but satisfying. "I spent years in a Catholic school so I understand from the kings of mind manipulation how human beings work," he says.

He left school at 17 with two O-levels and an A-level in art and became a DJ, making his way from Topshop, via Radio Caroline and Capital, to Radio 1. He also moonlighted as a hypnotist, having been impressed by a practitioner he interviewed on his radio show. He started practising on friends. At first it was a party trick where he'd turn people into washing machines, but soon he was selling out theatres. In 1993 ITV launched The Hypnotic World of Paul McKenna, on which volunteers were hypnotised into performing funny tasks. Viewing figures reached 13 million.

He could have been another Paul Daniels. But he wasn't happy. He cut down on the stunt TV and began using hypnosis to help individuals with problems or phobias. He met Richard Bandler, the Californian co-founder of NLP – a form of psychotherapeutic counselling developed in the 1970s. They started running seminars together and Bandler became his mentor, helping him to reprogramme his mind: "In the past I used to be quite controlling, almost robotic."

Today, Paul McKenna Training is the biggest hypnosis and NLP training centre in the world. But he has his detractors. In 1994 a participant on his show said he had developed schizophrenia as a result of being hypnotised. His claims were taken up in the national press – McKenna sued and won the libel case.

But another accusation pursued him. In 1996 he earned a PhD in hypnotherapy from LaSalle University in Louisiana, which turned out to be unaccredited. The Daily Mirror claimed McKenna knew the qualification was bogus. McKenna won damages. He went on to get what he calls a "proper" doctorate from a UK-based business school – and turned his PhD thesis into Change Your Life in Seven Days.

What's the worst thing people have said about him? "That I'm a fake, a fraud, that it's all pyramid selling; that I don't really care about other people, which I find hurtful. If I was interested in making money, I'd be in banking or oil." Stop worrying about hypnotists, he says bluntly, the real people to fear are cult leaders, politicians, lunatic religious leaders, salesmen – "all of whom coerce and manipulate people".

There is something endearing about McKenna, as easy as it is to represent him as part Wizard of Oz (small man, large megaphone), part Princess Di. A self-confessed geek, he describes his own life as a work in progress. Although he meets your gaze with authority, he is incredibly fidgety. He worries about going bald; he worries about his beaky nose. "Until a few years ago, I wasn't the major shareholder in my feelings," he has admitted. "I thought I needed a bigger house, more cars, more beautiful girls, more money, more fame. Then I tipped the other way. I realised I had everything I wanted and began to make peace with aspects of myself I hadn't wanted to admit to."

In fact, these days he and the psychological community are reading from the same page. Members attend his seminars. McKenna, once rabidly anti-therapy (he believes it takes too long), is working with positive psychologists, Jungian therapists, philosophers, you name it. "It's about training your brain to spot which moments you felt happy in and to search for more happy moments." And it's not enough to just have "slick skills"; compassion is everything, he insists.

There's no denying McKenna is a workaholic. He relaxes with trashy TV and going out to dinner: "I'm very sociable." Most days he practises Big Mind meditation, which encourages you to integrate the serene and shameful parts of yourself.

He accepts that people are fascinated by his love life. "People have a right to know if I walk my talk: whether I'm authentic and consistent." He has talked about being a commitment-phobe but admits: "I've had my heart broken, I've been trashed a few times." (past girlfriends include GMTV presenter Penny Smith and model Liz Fuller, who dumped him live on her cable TV show). His book I Can Mend Your Emotional Heart came from experience: Richard Bandler helped him recover with a technique developed for abused women. "Out of my pain came a resource for other people – and profit," he says, with a glint.

He says his girlfriend of 18 months, Niki Roe, a dog trainer, hates the limelight. "She doesn't like public events but does it for me, which I appreciate." On the walls of his flat he has silver-framed photos of his Great Dane, Mr Big. At 44, does he want children? "At the moment, I'm not sure, I don't think so. Although a friend said, 'Look how much you love your dog: imagine that for a child!' "

McKenna once boasted he'd be a millionaire by 30. His last book, 2007's I Can Make You Rich (based on talking to gurus from Philip Green to Richard Branson) was deliberately controversial – "it's meant to piss people off". He thinks the British are still encouraged to feel guilty about success. And actually there's an egalitarian streak. He thinks working people have been tricked into thinking poor by the ruling classes. "If you think money is bad, you will unconsciously sabotage your attempts to create more of it."

He's our top-selling non-fiction author and is about to go global. For the next year McKenna will be based in LA, where he's working on an interactive self-improvement television show. "It will be digital, downloadable. Clearly books will always be around but we'll be able to reach millions more. For a rich man he is working his butt off, but when his LA project is launched he says he may "nearly retire". I doubt it – he's too much of an evangelist. "I do want to help the person in front of me but at the same time I want to do a damn good job," he says. "So sometimes it's my outrageous ego. I won't stop until they're fixed."

Am I fixed? Two weeks on I'm not exactly embracing the postman but there's optimism. I like McKenna; he doesn't patronise and he understands wariness. He'd like to see me "open up enough for something good to happen", to take "evaluated" risk. He even diagnoses some self-sabotage. I'd go back. And I appreciate his honesty. "I've been asked to do books on relationships," he laughs, "and my own response is: if I can stay in one for long enough, I'll do one."

Paul McKenna's revised I Can Make You Thin is published by Bantam Press, priced £10.99.