You might not have heard of Josephine Fairley, but I suggest you start feeling grateful to her immediately. Without her, there would be no Green & Black’s. You can forget Maya Gold, the nation’s top selling, and first, Fairtrade product; we’d be back with Kit Kats and bad teeth.

Chocolate apart, Fairley has published several books showing us how to be beautiful and, more recently, championed alternative health. But don’t expect a green goddess, here is someone who is just as fond of the high life as she is of her organic vegetable patch.

Fifteen years ago, Fairley, 50, recognised the potential in making chocolate with a low-sugar and high-cocoa content. The hitch was that she needed to persuade her husband and business partner, Craig Sams, to come on board.

Sams was the founder of the macrobiotic food company Whole Earth and a health food fanatic. He had never sold anything that contained so much as a sprinkle of sugar. Later he described his conversion as “not unlike turning around an oil tanker”. Sweetened by his wife’s enthusiasm, the two of them set up Green & Black’s in 1991.

There’s another reason to thank Fairley. She has just published a new edition of her bestselling health and beauty manual giving women a handle on the booming beauty industry. Feel Fab Forever, co-written by the journalist Sarah Stacey, is a modern version of their previous international blockbuster The Beauty Bible (1996), which has sold nearly half a million copies in the UK. If the last one’s anything to go by, this compendium of reviews and tips, dealing with subjects from the superficial (eyebrow plucking) to the serious (beating depression), will be a Christmas bestseller.

And then there’s her bakery, Judges, in Hastings, East Sussex, where the couple moved four years ago. The products are traditional and include Eccles cakes and Scotch eggs, but organic. And an integrated health centre for the town is in the pipeline. Opening next year, it will have a GP to steer customers towards the right treatment. From Pilates to reiki and cranio-sacral therapy, Fairley says the aim was to bring the region’s many therapists under one roof.

It is little wonder that the two of them have been called Britain’s greenest (and richest)couple. Something Fairley tells me is not far off since the only non-organic product in their cupboards is Marmite. When we decide to meet for lunch, I wonder if she will choose a salad bar or Soil Association-certified pub. In fact, she plumps for the Wolseley, one of London’s most chichi eateries. It’s where she holds her London meetings. Not what I expected from a paragon of organic living. But then there isn’t a whiff of worthiness about Fairley. Wearing a smart black suit, she is blonde and poised, and looks as if she’d enjoy a good cocktail party.

At 23, she was the UK’s youngest female national magazine editor, first running Look Now and then Honey, later writing a column on the environment for The Times. “I’m not a sack- cloth and ashes kind of girl,” she says. “Nor do I think you have to be. When I lived in London, I’d be at the Groucho Club twice a week, then I’d eat organic food at home the other five nights. I don’t believe you have to lead a dull life to be green.”

I can’t help wondering whether her husband, who is now chairman of the Soil Association, is responsible for steering her away from London’s media circus towards a purer, more ethical existence (she hooked up with Sams after being sent to interview him about organic food).

“Not at all. I was the one to encourage him to recycle,” she says. “When I was 15, my first boyfriend gave me a guide to saving the planet. After that I used to bully my mother into driving her gin bottles to the village bottle bank, and I got into trouble for putting bricks in the school loo cisterns to save water.”

Fairley is keen to talk about the relationship between climate change and organic farming. “If you use organic methods, you lock carbon dioxide into the soil,” she tells me. But when I press her on exactly how and why this is different from conventional farming, she falters, saying: “Craig’s the expert; you’d have to ask him.”

I detect in Fairley a journalist’s ability to keep a finger on the pulse of what interests the public without necessarily knowing an awful lot about it. She doesn’t deny her beauty writing provides a stable income so that she can take on less financially predictable projects such as the bakery. But then, after Cadbury-Schweppes bought up Green & Black’s last year for £20 million, it is unlikely that she has to worry about where the next organic food delivery is coming from.

On alternative health, she admits that neither she nor Sams is an expert: “To run our health centre, we’re going to have a team of advisors on board.” But she’s had plenty of experience as a patient. She has regular massage, reflexology and acupuncture to de-stress and ward off annual bouts of bronchitis. A lifelong yoga fanatic, such is her belief in complementary (she prefers the word to “ alternative”) medicine that she has visited a GP only once in the past 18 years, and that for a skiing-related knee injury. “Health is a proactive thing and we all have to take charge of our own, before something goes wrong, not after,” she says.