A leading cancer expert has warned that taking vitamin supplements might do ‘more harm than good’.

The Daily Mail reports that Professor Martin Wiseman – medical and scientific adviser for the World Cancer Research Fund – has warned that high doses of some vitamins and nutritional supplements could actually cause harm.

Recent stories int he press may have encouraged many people to step up their intake of antioxidants such as vitamin C, in the hope that it will cut their risk of developing cancer and other serious illnesses.

However, Prof Wiseman says that the impact of such measures cannot be estimated nutritionally – and recent research has actually linked the development of cancer with some vitamins and supplements, including beta carotene, which can increase the risk of lung cancer in those who smoke.

Prof Wiseman said:

‘Many people think they can reduce their cancer risk by taking supplements, but the evidence does not support this. Just because a dietary pattern that provides a relatively high level of a particular nutrient might protect against cancer, it does not mean that taking it in tablet form will have the same effect.

‘In fact, at high doses the effect of these micronutrients is unpredictable and can be harmful to health.’

Prof Wiseman also advised that vitamins and supplements in tablet form would not contain other essential nutrients found in food, such as fibre.

‘The best advice is to have a healthy, plant-based diet with lots of fruits and vegetables, rather than relying on supplements,’ Prof Wiseman added.

© 5r1 Limited 2009