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Vitamin C is a Call for Complementary Care in Cancer
Nutrition is perhaps the most fundamental aspect of health. At the most critical level, oxygen starvation can lead to death within minutes; the effects of sub-optimal dietary habits are more subtle and occur over the course of many decades. Adequate nutrition is so vital that it goes without saying that health is more important than disease.
It surprises me then, that in some of my cancer patients with near end-stage disease, nutritional aspects of therapy are overlooked. In fact, any nutritional intervention outside of keeping a patient’s weight up is often seen as counter-productive to conventional cancer therapy. Conventional physicians will often say that there is a danger that the anti-oxidant compounds in natural medicines and supplements will negate the effects of either radiation therapy or chemotherapy. This has been a valid concern in the past, as studies were definitely lacking as to whether or not antioxidant compounds interfered with the oxidative killing mechanism of radiotherapy and chemotherapy. In current research though, the usual finding is that moderate to high doses of natural compounds, including some antioxidants, actually potentiate the effect of chemotherapy and radiation while allowing the patient to be healthier during treatment (a naturopathic physician or holistic medical doctor should be consulted during conventional therapy though). It is obvious to most that if we keep the nutritional status of patients up, they will be healthier and be able to tolerate their conventional treatments much more comfortably.
In no better situation has the safety and potential efficacy of nutritional treatments in cancer been shown than for vitamin C. A review of the literature for vitamin C use in cancer and its supportive nutritional use in chemotherapy and radiotherapy should serve as a wake-up call to all physicians. Nutritional treatments such as vitamin C, even in the massive doses used by naturopathic physicians in adjunctive care for cancer patients, do not interfere with conventional treatments and in fact have documented positive effects.
Linus Pauling was the first to popularize the concept that vitamin C can be used in cancer treatment.# Controversy stirred and most conventional physicians believed the question was definitively answered by a Mayo Clinic study that showed no benefit for vitamin C in cancer.# This Mayo Clinic study used only oral dosing of vitamin C (ten grams) and showed no difference in survival times compared to placebo. Of note is that in order to achieve therapeutic blood levels of vitamin C, intravenous dosing needs to be used. This was definitely shown and published last year.# The study showed that intravenous levels of vitamin C were able to act as a pro-drug in order to deliver hydrogen peroxide to tissue.
The Canadian Medical Association Journal published this year a report that followed 3 well-documented patients who had undergone intravenous vitamin C therapy.# The case reports showed that survival was clearly prolonged in those patients. In the same journal, two doctors reported that they were instituting a trial of vitamin C therapy in their hospital - they noted that spontaneous remission has been previously recorded in other cancer patients, and rightly that 3 case reports can disguise a far lower success rate if many other patients were treated unsuccessfully.# These doctors are to be commended for taking the step of investigating the vitamin C therapy further. I doubt that any physician would suggest intravenous vitamin C or nutritional therapy as the only treatment for a patient with cancer, but I do believe that this information suggests that nutritional therapy can offer benefit to patients without interfering with conventional therapy.
In fact the issue has been studied before. One study in non-small cell lung cancer patients showed that a combination nutritional treatment with beta-carotene, vitamin C, and vitamin E did not interfere with the effect of chemotherapy.# A test tube study showed that vitamin C increased the anti-cancer activity of the chemotherapeutic drug 5-FU,# and vitamin C alone may increase breast cancer cell susceptibility to 3 other chemotherapeutic drugs.# Overall, the research seems to indicate that the best course of action is a combination of complementary and adjunctive therapy (including things like optimizing nutritional statues, and more aggressive measures such as intravenous vitamin C) along with conventional therapy. When done under professional supervision by a physician (naturopathic doctor or holistic medical doctor), I can see only benefit for the patient. The age-old idea of drugs and surgery being exclusive of naturopathic and nutritional medicine should clearly be discarded.
Dr Eric Chan, ND
# References:
# Cameron E, Pauling L. Ascorbic acid and the glycosaminoglycans. An orthomolecular approach to cancer and other diseases. Oncology. 1973;27(2):181-92. Review.
# Creagan ET and others. Failure of high-dose vitamin C (ascorbic acid) therapy to benefit patients with advanced cancer. A controlled trial. New England Journal of Medicine 1979 301:687-690.
# Chen Q, Espey MG, Krishna MC, Mitchell JB, Corpe CP, Buettner GR, Shacter E, Levine M.
Pharmacologic ascorbic acid concentrations selectively kill cancer cells: action as a pro-drug to deliver hydrogen peroxide to tissues. Proc Natl Acad Sci U S A. 2005 Sep 20;102(38):13604-9.
# Padayatty SJ, Riordan HD, Hewitt SM, Katz A, Hoffer LJ, Levine M. Intravenously administered vitamin C as cancer therapy: three cases. CMAJ. 2006 Mar 28;174(7):937-42.
# Assouline S, Miller WH. High-dose vitamin C therapy: renewed hope or false promise?
CMAJ. 2006 Mar 28;174(7):956-7.
# Pathak AK, Bhutani M, Guleria R, Bal S, Mohan A, Mohanti BK, Sharma A, Pathak R, Bhardwaj NK, Prasad KN, Kochupillai V.
Chemotherapy alone vs. chemotherapy plus high dose multiple antioxidants in patients with advanced non small cell lung cancer.
J Am Coll Nutr. 2005 Feb;24(1):16-21.
# Nagy B, Mucsi I, Molnar J, Varga A, Thurzo L.
Chemosensitizing effect of vitamin C in combination with 5-fluorouracil in vitro.
In Vivo. 2003 May-Jun;17(3):289-92.
# Kurbacher CM, Wagner U, Kolster B, Andreotti PE, Krebs D, Bruckner HW.
Ascorbic acid (vitamin C) improves the antineoplastic activity of doxorubicin, cisplatin, and paclitaxel in human breast carcinoma cells in vitro.
Cancer Lett. 1996 Jun 5;103(2):183-9.
