大象传媒

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The theory behind detox diets is that you can get rid of toxins by increasing liver and kidney function. In the third of his 'How to stay young' films, Michael Mosley met Andy and Ally.

For seven days, Ally followed Ursula Arens' detox diet plan while Andy continued to eat his usual diet. For seven days Ally ate no wheat (bread and pasta) dairy or chocolate, but drank lots of water and ate lots of nuts, seeds, fruit and vegetables. Both men drank no alcohol for seven days.

After one week, Dr David Goldsmith, a consultant nephrologist, compared Andy and Ally's livers and kidneys.

And the results? The diet made no difference to Ally's kidneys. But both men's livers improved slightly, which Dr Goldsmith put down to the absence of alcohol.

Dr Goldsmith suggests that a detox diet makes little difference in the short term, but may be healthier if followed over a longer period of time.

Do detoxes work? What diet do you recommend for good health? Add your comment.