Antioxidants may not fight cancer, according to research

the Oncology Nurse Advisor take:

A research meta-analysis suggests that the anti-cancer properties of antioxidants may have been overstated, and that, in some cases, antioxidants could even have an adverse effect with regard to cancer.

Researchers based at Cold Spring Harbor Laboratory, New York, conducted a review of previous studies addressing the effects of antioxidants, molecules that help prevent cell death by removing free radical intermediates, on cancer and cancer prevention. Although a number of early preclinical studies appeared to show that antioxidants can help fight cancer, they found that dietary antioxidants did not reduce the incidence of carcinoma in prospective human clinical trials. One surprising finding was that, in some studies, antioxidants seem to show an adverse effect on patients; one such example the researchers cited was the the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Trial, wherein smokers taking a 20-milligram antioxidant supplement (in this case beta-carotine) actually showed a 18 percent increase in lung cancer incidence and an 8 percent increased mortality when compared with the non-supplement group. Another study, published published in early 2014 in the journal Science Translational Medicine, found that lung cancer was accelerated in mice when they were given vitamin E and N-acetylcysteine (both antioxidants).

The researchers think that antioxidants may not be effective in combating cancer because they are not targeting the correct cell sites. Future studies examining the exact pathways of antioxidants within cancer cells are needed, the researchers said.