Pierre Dukan has been struck off the medical register in France for commercialising the high-protein diet that bears his name.
The national medical board took the decision on the grounds that the nutritionist, who retired in 2012, had "promoted his slimming diet commercially" and had suggested there should be an "anti-obesity" test in the national baccalaureate, French medical agency APM reported on Saturday.
The regulations of the Order of Doctors bar medical practice from being a commercial venture.
The Dukan diet, similar to the Atkins low-carb diet, has been hugely successful around the world since it was launched in France in 2000 with the publication of Dukan's book Je Ne Sais Pas Maigrir (I Don't Know How to Lose Weight).
Celebrity followers reportedly include the singer Katherine Jenkins and the actor Penelope Cruz.
Dukan's empire includes a coaching business and online shops.
Weight loss in phases
The diet comprises four phases: slimmers move from a pure protein "attack" phase, in which rapid weight loss occurs, to "cruise", which allows 28 selected vegetables on some days so that dieters reach their "true weight".
The third phase, consolidation, permits additional starchy foods to be added before the final phase, permanent stabilisation.
But the calorie-crunching regime has recently been criticised in the academic press over potential health risks.
In a study by Granada University in Spain, experiments on rats found that high-protein diets like the Dukan regime may increase the chance of developing kidney stones and other renal diseases.
Dukan asked to leave the medical profession voluntarily when he retired in May last year.
In addition to looking into how he was promoting the Dukan diet, the order's disciplinary committee focused on his call for schoolchildren to learn about "weight equilibrium" and be regularly weighed and given points depending on progress.
The education ministry accused the doctor of "unconscious physical discrimination" against pupils, but Dukan refused to back down and sent his proposals to all the presidential candidates in France's 2012 elections.
Dukan was subsequently barred from practising medicine for a week by the medical board in October last year and ordered to pay €6 000 to a former patient for breaching ethical rules. – © Guardian News and Media 2014
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