Karma Cookbook by Boy George and Dragana G. Brown published by Carroll and Brown, priced £12.99.

Back in the mid-1980s when Boy George was a pop star at the height of fame, lunch at his home would have been unlikely.

He used drugs while "generally living a life of debauchery", and could barely open a tin of baked beans. But like a chameleon, George has transformed into a clean-living DJ who can cook, loves healthy macrobiotic food and has co-written Karma Cookbook, published on Thursday, June 14 - on his 40th birthday.

When I arrived at his 19th century, Gothic-style mansion in leafy Hampstead, north London, George led me through an imposing hallway with mosaic floor into the kitchen - a cook's dream, with acres of pale-coloured fitted units, terracotta floor and a huge wooden table. The whole house has been decorated with the help of a Feng Shui expert - George has given up pink frills and a jacuzzi in his bedroom, for a huge wooden bed and an ensuite bathroom with a glass ceiling and brass bath.

The newly domesticated star cheerfully accepts he is heading towards middle age, and is proud of his new culinary skills.

"I can cook pretty well," he says. "One of my best friends, Amanda, is from a Spanish-Indian family and we often spend a few hours in the kitchen. She'll come round with one of her mum's recipes and I'll say, 'We'll do it this way, but we'll miss out the sugar'."

Deciding to eat macrobiotically requires some major adjustments.

As we sipped caffeine-free bancha twig tea, George and his co-author Dragana Brown explained that meat, dairy products and sugar were to be avoided. The diet - from the Greek words "macro" meaning great and "biotos" meaning life - revolves around grains, vegetables, beans and soy products. Oh, and you are supposed to munch vegetables at breakfast.

George explained: "If you eat a bowl of porridge, you just have some steamed broccoli with it. Some people who see me eating vegetables for breakfast think it's appalling, but if you have Japanese breakfast in a hotel, you get vegetables. So it's not that weird."

Dragana, one of George's closest friends since 1989 when he met her at a macrobiotic centre, dropped another bombshell: When you eat this way, you are supposed to chew each mouthful of food at least 30 times, ideally 50 times, before you swallow.

As I used chopsticks to tuck into soba noodles, lettuce with sesame oil and blanched broccoli and carrots, I decided macrobiotic cooking was worth trying after all. Though suspiciously healthy, the food was delicious. The sugar-free apricot dessert even tasted sinful.

George thinks the diet gives him more energy - useful on his deejaying tour of the States. He's working on a musical, planning a solo record in the autumn, and also considering becoming a TV chef. It seems he and Dragana have been offered their own show.

Astounding changes, but the old, flamboyant Boy George hasn't vanished - 700 guests attended his birthday party in the West End as dandies or courtesans.