He advised that people should eat a balanced diet with plenty of fruit and vegetables.

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However he said it had been established that eating a balanced diet, which was high in fibre plus plenty of fruit and vegetables, lowered the risks of developing many forms of cancer.

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He said humans generally have plenty of carnitine in their diet, which also is found in small amounts in nuts, beans, vegetables and fruit, and don't need to take it in supplement form.

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