Antioxidant Supplementation in Cancer: Potential Interactions with Conventional Chemotherapy and Radiation Therapy

The use of supra-dietary doses of chemical antioxidants has attracted increasing interest as a possible primary and secondary cancer prevention strategy. It is possible that some cancer patients have an inherently impaired capacity to contend with oxidative stress because of genetic or environmental factors. Specifically, higher levels of intracellular antioxidants may protect against chromosomal injury induced by UV radiation and xenobiotic induced oxidative stress. Vitamin A and carotenoids, vitamin C, vitamin E, selenium, and glutathione may alone or in combination afford protection. Chemotherapy and radiation therapy result in depletion of tissue antioxidant stores. Antioxidant supplementation may be an important part of recovery from conventional therapy and perhaps have impact on secondary prevention.