Do antioxidants help prevent cancer?
Over the last several years, a body of evidence has been growing, showing that antioxidant supplements do not help prevent diseases. A recent study in the British journal Lancet (v 364, p1219, 2004) reviews a large body of data - 14 randomized trials, with 170,525 participants. They find that vitamins A, C, E and the element selenium, show no significant mitigation of risk compared to taking a placebo. The overall risk reduction was found to be 0.96, with a range of 0.88 to 1.04 at the 95% confidence level.
Morever, in seven high quality studies, their analysis shows an increased mortality (risk ratio of 1.06, with 1.02 to 1.10 at the 95% confidence level)!
Additional details are available at our antioxidant study site.