In order to check the activities of ROS/RNS your body evolved antioxidant systems that consist of biological antioxidants (e.g., vitamin C, vitamin E, and glutathione) and antioxidant enzymes (e.g., super-oxide dismutase, catalase, and glutathione peroxidase). However, under times of duress, these systems get easily overwhelmed and free radicals run rampant.
When you undergo chemotherapy or radiation high levels of ROS/RNS typically remain in the body even after treatment. When this happens they may contribute to increased nervous system inflammation. In fact, research has shown this process may be the driving factor in memory and cognitive issues commonly seen after chemotherapy and radiation (1).
Giving antioxidants such as vitamin C, vitamin E, alpha lipoic acid and glutathione has been controversial in cancer treatment, because many think that antioxidants neutralize the actual intended free radical damage effect of radiation and some chemotherapy in the killing of cancer cells.
Others think that these anti-oxidants are useful in cancer treatment, because they neutralize oxidation which in turn supports the proliferation of malignant cells thus adding to cancer. This view maintains that antioxidants may counter the harmful effects of oxidation in the malignant process and thereby increase the effects of drugs or radiation therapy to the benefit of the patient. Moreover, they note that some evidence suggests that antioxidant supplements offer patients protection from the toxic effects of therapy, “mopping up” the collateral damage done by these treatments.
An article published in 2007 supports this view. Researchers form the Simone Protective Cancer Institute in Lawernceville, NJ (2) “looked at 280 peer-reviewed studies, including 50 human studies involving 8,521 patients, 5,081 of whom were given nutrients have consistently shown that non-prescription antioxidants and other nutrients do not interfere with therapeutic modalities for cancer. Furthermore, they enhance the killing of therapeutic modalities for cancer, decrease their side effects, and protect normal tissue. In 15 human studies, 3,738 patients who took non-prescription antioxidants and other nutrients actually had increased survival”.
More recently, the epicenter of dual treatment of cancer with conventional treatments (chemotherapy and radiation) AND vitamins C has been The University of Kansas Hospital. Dr. Qi Chen has conducted several human trials showing the effectiveness of High Dose Vitamin C as an oxidant alongside chemotherapy. For an FAQ of their 10-chair integrative IV cancer infusion clinic click here.
Dr. Weil’s summarized the answer to the question of antioxidant use in cancer in 2006 this way:
“As things now stand, we need more research before we can confidently advise patients one way or another. However, I posed (this question) to Donald Abrams, M.D., an integrative oncologist at the University of San Francisco and a graduate of the associate fellowship at the Program on Integrative Medicine here at the University of Arizona. Dr. Abrams told me that questions about antioxidants are the most frequent ones he gets. In the absence of strong evidence, he now advises patients as follows:
- For those being treated for a possible cure (meaning that their tumors have been removed and that the goal of chemotherapy or radiation is to destroy any remaining cancer cells): Don’t take antioxidant supplements on the day before, the day of, and the day after chemotherapy. Otherwise, it is okay to take supplements.
- For patients undergoing radiation therapy: no antioxidant supplements throughout the course of treatment.
- For patients with advanced cancer who are being treated in order to prolong survival and relieve symptoms: it is okay to take antioxidant supplements. Because chemotherapy agents differ in their mode of action, it would be helpful to know whether the particular drugs being used work by an oxidative (free-radical-generating) mechanism. Ask the medical oncologist treating you for that information.
By the way, there is no justification for telling patients undergoing chemotherapy or radiation therapy to avoid antioxidant-rich foods.”
Ultimately the decision to use antioxidants as an adjunct to alleviate cancer treatment and side effects is a personal decision which should be arrived at with careful consideration of risk and benefits with one’s oncology doctor.
References
- Ahles TA, Saykin AJ. Candidate mechanisms for chemotherapy-induced cognitive changes. Nature Reviews Cancer, 7(3), 192-201.
- Simone CB, Simone NL, Simone V, Simone C B Antioxidants and other nutrients do not interfere with chemotherapy or radiation therapy and can increase kill and increase survival, Part 2. Alternative therapies in health and medicine, 13(1), 22.
- Ma Y, Chapman J, Levine M, Polireddy K, Drisko J, Chen Q.. High-dose parenteral ascorbate enhanced chemosensitivity of ovarian cancer and reduced toxicity of chemotherapy.Science translational medicine, 6(222), 222ra18-222ra18.