Meta-analysis finds antioxidant supplementation safe during cancer therapy

April 20, 2007
Meta-analysis finds antioxidant supplementation safe during cancer therapy
The January/February and March/April 2007 issues of the journal Alternative Therapies published a two part article by a team at the Simone Protective Cancer Institute in Lawrenceville, New Jersey, which concluded that, contrary to long-held beliefs, antioxidant and other nutritional supplementation during chemotherapy or radiation does not interfere with these treatments.
"A single, front-page interview in The New York Times in 1997, which was not based on published scientific work, and a single research paper involving mice, along with a press release by its author in 1999, led to the erroneous notion that vitamin C interferes with chemotherapy and radiation in humans," the authors write. "This notion soon applied to all antioxidants as physicians, patients, the media, the American Cancer Society, and scores of websites took the same position without reviewing the scientific evidence."
For their meta-analysis, oncologist Charles B. Simone, MD, and colleagues identified 50 human studies that included a total of 8,251 participants involving the use of chemotherapy and/or radiation concurrently with dietary supplements. They discovered that antioxidants and other supplements failed to interfere with the treatments and were actually found to enhance them. In 47 of these studies, supplements were associated with protection of normal tissue and a reduction of side effects, and in 15 studies, 3,738 subjects experienced increased survival.
The authors explain that, due to a loss of the homeostasis control mechanism for the uptake of antioxidants, cancer cells accumulate large amounts of the nutrients, while healthy cells do not have this membrane defect. This accumulation decreases the oxidative reactions needed for the generation of the cells' energy. Additionally, the nutrients elicit other effects on cancer cells unrelated to their antioxidant activity.
The authors concluded that "Antioxidant and other nutrient food supplements are safe and can help to enhance cancer patient care."