But those fad diets would never last more than a few weeks, and his weight would rebound.

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They also published a health newsletter, including recipes and a critique of fad diets, and distributed it to co-workers.

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Rick Miller, a clinical dietician and spokesperson for the British Dietetic Association, said fad diets could cause major issues.

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Equalities minister Jo Swinson wrote an open letter asking magazines to "shed the fad diets and fitness myths" in their January editions.

BBC: Magazine 'miracle' diets should be 'dropped'

Experts have known for decades that extended crash diets can be dangerous -- especially when the diets become a fad.

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Some diet experts say that even the best diets are unlikely to be successful, either because people are unrealistic in their goals or because "diets"--fad or otherwise, falsely advertised or not--tend not to work.

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Are low-carb diets like Atkins a passing fad?

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