Call for Stronger Recommendations About Supplement Use During Chemotherapy

December 1, 1999

The article by Drs. Labriola and Livingston is the first written collaboration of which I am aware between a doctor of naturopathic medicine and a professor of medicine at a major state university. The authors present a thorough review of the available information on interactions between dietary antioxidants, both natural and supplements, and chemotherapy.

The article by Drs. Labriola and Livingston is the first written collaboration of which I am aware between a doctor of naturopathic medicine and a professor of medicine at a major state university. The authors present a thorough review of the available information on interactions between dietary antioxidants, both natural and supplements, and chemotherapy.

Of necessity, the review relies heavily on interactions observed in the laboratory and animals, since little, if any, human data appear to be available. In fact, the only reference cited that seems to bear directly on this issue in humans, by Erhola et al, was published in the fairly obscure journal Free Radical Biology and Medicine. Even this reference contains no clinically useful information, however. Also, it provides no data to justify the assertion by Labriola and Livingston that “such a reduction in concentration of free radicals generated by chemotherapeutic agents has the same effect as a reduction in dose.”

Nonetheless, the authors raise grave concerns about the possibility that cancer patients may jeopardize their ultimate chance of cure and survival by taking various dietary supplements with antioxidant activity during chemotherapy programs. If this may be a potentially major public health issue, however, the authors’ remedies are surprisingly low key. One would have expected that, given that there is proven scientific evidence of the value of chemotherapy and no evidence for the value of dietary supplements, the authors would have recommended against dietary supplements entirely!

Drs. Labriola and Livingston are very well known to the medical community, as well as the press in the Northwest. Their article received wide coverage in the local media. One would have hoped that such prominent authors, whose opinion carries great weight with both their professional peers and laypeople, would have made a stronger statement against the use of dietary supplements during chemotherapy. Media coverage of such a recommendation might have saved lives.

Charles M. Bagley, Jr, MD
Northwest Cancer CenterSeattle, Washington

The Authors Respond

In questioning the interactions between dietary antioxidants and chemotherapy, Dr. Bagley emphasizes the Erhola et al study (our reference 23), which, he feels, does not provide “clinically useful information.” Dr. Bagley further suggests that we should have made “... a stronger statement against the use of dietary supplements during chemotherapy.”

Our article describes the interactions between dietary antioxidants and certain chemotherapeutic agents with applicable citations. The Erhola et al reference is a human study that actually measures the interaction, in vivo, between anthracycline-generated free radicals and plasma total peroxyl radical trapping antioxidant parameters (TRAP), including their main antioxidant components. The study clearly demonstrates the interaction between reactive oxygen species generated by the chemotherapeutic agents and TRAP. It is included in our article as a credible, novel, additional method for demonstrating these interactions.

In writing this article, our objective was to provide more knowledge to support, not to usurp, the physician’s clinical decision-making process. Many responsible clinical oncologists, including peer-review physician Dr. Mark Ratain, take the position of excluding utritional supplementation during cancer treatment to protect their patients.

Eisenberg et al (our reference 1) suggest that some patients may not comply with this advice from their oncologist. However, this is only one of several clinical options described in our article. In our view, this decision belongs in the hands of the clinician. Given today’s environment of scientific and public interest in the use of antioxidants in oncology, combined with suggestive new research being published, a blanket statement eschewing the use of dietary supplements is neither appropriate nor realistic.

Qualifications of Naturopathic Doctors Vary

Dr. Bagley’s comments regarding collaboration between naturopathic doctors and medical physicians has clinical significance for medical oncologists. Many of today’s cancer patients are seeking out alternative medicine practitioners, including naturopathic doctors. This can create a dilemma for physicians who are concerned about the qualifications of those who are giving their patients advice. Although some licensing entities have taken reasonable steps to protect the public (and patients’) interest by controlling who can offer health care, others have not yet addressed this issue.

For example, in Washington State, arguably among the most competent and advanced licensing jurisdictions for health care providers, a naturopathic doctor must complete a physician-level training program from an approved accredited institution, pass national board examinations, and then be subject to rigorous licensure, enforcement, and regulation. Contrast this to Washington, DC, where an individual with a weekend mail-order diploma (or even less formal training) can register to practice naturopathy. We all recognize that licensure does not offer a guarantee of performance for any profession. However, the standards and regulatory scrutiny afforded by a regulated environment provide patients with at least some basic protections. Until stringent protections, such as those in Washington State, are uniformly in place in other jurisdictions, physicians and patients will have to take extra care in selecting nonconventional providers.

Both alternative and complementary medicine are now facts of life in western culture. When patients indicate an interest in utilizing nonconventional treatments, many medical specialists insist that their patients use providers in whom they have confidence. In some cases, this can mean a long-distance consultation, which, admittedly, may not be an ideal solution. However, at the very least, it can prevent the situation in which, unbeknownst to the physician, the patient receives uninformed, possibly dangerous advice that could adversely affect the outcome of treatment.

Dan Labriola, ND
Robert Livingston, MD