James Duigan has made his name sculpting the bodies of some of the world’s most successful supermodels, from Elle Macpherson to Rosie Huntington-Whiteley. But the Australian expat remembers being star struck just once. “I met Leonardo DiCaprio a few years ago in LA. I couldn’t stop smiling,” he admits. “That’s the only time.”

Duigan launched his training business in London in 2000, four years after arriving in the city essentially penniless. Now, the Adelaide-born entrepreneur presides over a fast-growing wellness empire that encompasses the exclusive celeb-friendly Bodyism gyms; a best-selling series of Clean and Lean recipe books; and much-sought after ranges of workout wear, supplements and tea.

Surprisingly, underpinning his popular health philosophy is the notion of kindness. “Clean and Lean is about being kind to yourself. It’s understanding that you do deserve a happy and healthy life,” he says. “It’s about valuing yourself enough to choose foods that are going to make you feel good.” Take the right approach to health, Duigan says, and weight loss is easy. “It takes care of itself,” he shrugs.

Adding weight to Duigan’s words is his long list of satisfied celebrity clients, including Bodyism ambassadors Huntington-Whiteley and Macpherson, several Victoria’s Secret angels, and Nigella Lawson. Their testimonials help explain the rapid expansion of Duigan’s empire in recent years. Bodyism clubs in Turkey, Capri and now the Maldives have followed the flagship gym in London, –– where Duigan lives with his wife and business partner, Christiane – and their two children, Charlotte (three) and Leo (one). A new Clean and Lean cafe in Notting Hill serves nutritional snacks to health-conscious clientele. In 2016, standalone Bodyism wellness clubs, complete with a suite of luxury services such as air purification, UV lighting to provide Vitamin D and vitamin infusions, will open in LA and Miami. A concept store is planned for Paris, and Duigan’s books, supplements and clothing range are scheduled to launch in the US.

Australia is part of the plan, too. “Australia’s a huge part of our business, and it’s very much in our hearts,” says Duigan. Bodyism Active Wear will be available directly to Australian customers for the first time thanks to a partnership with Stylerunner. His latest book, Clean and Lean for Life: The Cookbook, lands in bookshops in December, and in 2016 Bodyism retreats will be offered in a, “beautiful nine-bedroom house” in Byron Bay.

He is highly critical of the trend that sees people turn to Instagram for serious health advice. “There’s a lot of insanity on social media,” he says. “Completely unqualified people with 4 million followers [are] giving out advice that’s dangerous and harmful, and playing into people’s insecurities. It’s really scary.” With over 100,000 fans following his own various social media accounts, Duigan acknowledges that social media is not bad in itself. “It’s been a huge part in the rise of wellness, but it also creates a lot of insecurity and unhappiness.”

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While Duigan acknowledges the difficulty of sorting through the mass of conflicting advice about health currently in circulation, he entreats people to exercise common sense. “Don’t give into crazy fads,” he warns, citing the marketing “con” of the gluten-free tag. While many people truly do have sensitivity to gluten, many gluten-free products are far from healthy. “Gluten-free things like muffins are generally full of sugar, and if it’s not refined sugar, it’s the pretend sugar like dates, brown rice syrup, and coconut unicorn fairy dust. It’s all the same.”

Duigan talks a lot about kindness and blessings, but it’s hard not to see his success as anything but the product of hard work and discipline. He epitomises the clean-eating ethos, eschewing “toxins” such as caffeine, alcohol and sugar.

Clean & Lean for Life: The Cookbook is in bookstores now.