Vis Medicatrix Naturae or Medicine? An Evaluation of Naturopathy and the Healing Power of Nature
By: Benjamin Mora
Scientists and physicians alike would be very naïve to ignore the increasingly obtrusive elephant in the room: Naturopathic or Complementary and Alternative Medicine (CAM). Much to the author’s chagrin, the use of CAM in the USA has virtually doubled, from approximately 34% in 1990 to 62% in 2002.(1) The 2007 National Health Interview Survey (NHIS) estimated that 38% of adults use CAM.(2) Patients are increasingly seeking out alternative medical therapies, either as a complement to traditional medical treatments, or as a replacement.
CAM is an umbrella term encompassing medical products or practices that are not part of standard care, that is, not used by conventional health professionals. The National Center for Complementary and Alternative Medicine (NCCAM) defines CAM as “a group of diverse medical and health care systems, practices, and products that are not generally considered a part of conventional medicine [i.e. “Western” or “Allopathic”]”.(2) CAM therapies include dietary supplements, botanicals, meditation, acupuncture, tai chi, hypnotherapy, spinal manipulation, massage, qi gong, iris diagnosis, magnet therapy, light therapy, and Reiki, among many others.
While naturopathy has its formal origins in the 19th century “natural living” movement in Germany,(3) it began in the USA in 1902 with medical doctor Benedict Lust, who himself was taught by the Nature Cure practitioner Father Kneipp in Europe.(4) Naturopathic medicine today, as taught at the Canadian College of Naturopathic Medicine (CCNM) in Ontario, primarily utilizes Asian medicine, acupuncture, clinical nutrition, botanicals, and homeopathy.(5) Though formally trained in these modalities, the Naturopathic Doctor (ND) is afforded the autonomy and freedom to utilize any CAM therapy, as long as it is deemed safe and “effective,” of course. An ND is trained as a primary care provider (comparable to a family physician) in a four-year program designed to parallel the curriculum of an allopathic medical school. In order to complete the program, students must pass the Naturopathic Physicians Licensing Examinations (NPLEX).
NDs are guided by six fundamental healing principles, a few of which include: Tolle Causam (identify and treat the causes); Tolle Totum (treat the whole person); and Vis Medicatrix Naturae (the healing power of nature). As for the last principle, Natura Medica, it should be obvious that nature is not always healing. From an evolutionary perspective, a sort of Darwinian Medicatrix Naturae seems intuitive. Evolution only selects for traits that are advantageous at the time. These traits may lose their purpose in the future or even develop into a hindrance when coupled with additional traits. With all the chicanes and detours in evolutionary history, the mechanics of the human body have evolved for survival advantage, not for optimal health per se. Medicine is to be guided by science—rigorous evidence-based science—not by philosophy or by ancient wisdom. Naturopathic medicine seems to exhibit a sort of respect or adoration for “ancient wisdom,” but is it not exactly the rise of modern science and modern medicine that have freed us from the non-evidence, superstitious-based “wisdom” of the ancients? Naturopathy should not have guiding philosophical principles but evidence and evidence alone as a guiding principle.
Often, Naturopathic medicine identifies simplified theories to explain the causes of disease, such as ubiquitous “toxins”; widespread food allergies; dietary sugar, fat, and gluten; vitamin and mineral deficiencies; epidemic candidiasis; vertebral misalignments; intestinal “dysbiosis”; or imbalances of Qi, to name a few.(3) The evidence for the theories and modalities utilized by NDs ranges greatly in quality and quantity, from relatively sufficient, to extremely inadequate and poor. Many CAM therapies are by definition inadequately researched, and are thus not utilized by medical doctors (MDs). Nevertheless, some therapies are evidence-based. For instance, a significant amount of evidence exists for many of the nutritional guidelines that NDs prescribe to their patients. It is well established in the medical literature that a diet high in fruits and vegetables, whole grains, nuts and seeds, and low in saturated fat, processed foods and meats, and refined sugars is conducive to health and longevity. Moreover, this diet has been shown to decrease the incidence of numerous chronic diseases such as cardiovascular disease, heart disease, obesity, type 2 diabetes, metabolic syndrome, and various cancers. Utilization of dietary interventions, micronutrients, vitamins and minerals (where evidence to do so is substantial), seems very helpful for patient health and for decreasing the burden of numerous chronic diseases on the health care system. MDs can learn from NDs in their use of diet, nutrition and lifestyle interventions.
Some of the modalities used by NDs suffer from lack of evidence and efficacy.
One of the cornerstone modalities of Naturopathic medicine is homeopathy. Founded by Samuel Hahnemann in the late 18th century, homeopathy is a philosophy-based medicine, centered on the principle of similia similibus curentur (like cures like), or the Law of Similars.(5) A substance which would produce symptoms of illness in a healthy individual is believed to cure similar symptoms of illness in a sick individual. Homeopathic remedies are prepared with thousands of serial dilutions in alcohol or distilled water. Many of the remedies often used are diluted beyond the dilutional limit, well beyond the limit of Avogadro’s number. With literally no active substance left in the actual tincture of water administered to the patient, the only explanation left is some convoluted theory in quantum mechanics or string theory; or some sort of “water memory” effected by changes in pressure, epitaxy, and/or nanobubbles brought about through the successing process.(6)
Theory aside, the clinical evidence for the effectiveness of homeopathy is wanting, with much of the data presenting conflicting or null results. In 2002, an analysis of eleven systematic reviews found that homeopathic remedies are not clinically different from placebos.(7) In 2005, a Lancet review of 110 homeopathy trials concluded that when analyses were restricted to large trials of higher quality, there was no convincing evidence that homeopathy was superior to placebo.(8) In 2010, an evaluation of six Cochrane reviews concluded that homeopathic medicines do not show effects beyond placebo.(9) It is hard to say which is more surprising: the fact that these absurd dilutions have been used by practitioners for over 200 years, or that research efforts and government funds continue to be invested in trying to validate this pseudo-scientific quackery. Normally it would be appropriate to raise concerns over safety or inspection, and lack of regulation by the FDA or external agencies, but then again, it is only water being administered anyway.
Each of the modalities used by NDs need to be evaluated in its own right. Evidence exists to suggest that many of the botanicals used by NDs may provide some benefit. However, knowledge of drug-herb interactions is limited and often preclinical data evaluating botanicals is erroneously generalized to human situations haphazardly.10 Another major modality utilized by NDs is Asian medicine and acupuncture. Traditional Chinese Medicine is based on ancient folk wisdom with yin yang, Qi, five elements, meridians, etc. Acupuncture should only be used where a sufficient number of properly conducted clinical trials exist. Problems arise in designing properly controlled studies, with difficulties in blinding and creating adequate placebo groups.
Perhaps even more interesting than the evidence or lack of evidence for naturopathic medicines and CAM therapies are the sociological questions, such as why are people attracted to CAM; why are young, intelligent students drawn to the field of Naturopathic medicine; and why does the field of naturopathy continue to thrive in a society that increasingly stresses science, evidence and rationality? Health-care consumers are drawn to this holistic, “natural” alternative, repelled and dissatisfied by Western biomedicine, perhaps due to lack of successful treatments, failed therapies, or fear of exaggerated side-effects of pharmaceuticals. Many patients are put off by the disease-focused, technology-driven biomedical model. Often, use of CAM is coupled with conspiratorial thinking regarding the unreliability of, and supposed biases present in scientific research. The blatant lack of concern of patients for the inadequacy of reliable evidence, and the implicit trust in folk wisdom, is alarming. But of course, it is probably the case that most patients seeking CAM are ignorant of the scientific evidence—they seek treatment from NDs on ideological grounds. The pseudoscientific components aside, to the credit of Naturopathic medicine, at least it emphasizes healthy lifestyle, values prevention, and uses less-invasive intervention.
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2. National Center for Complementary and Alternative Medicine (NCCAM). [homepage on the internet]. Health Info. What is Complementary and Alternative Medicine?[updated 2011 July; cited 2013 January]. Available from: http://nccam.nih.gov/health/whatiscam
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