Note: This is an inordinately long post: there was so much I wanted to say! If you don’t have the time or inclination to read it all, I hope you will read the conclusion and dip into the rest enough to appreciate that the conclusion is justified.

I recently had the opportunity (perhaps I should say the misfortune) to spend many days perusing the major textbook of naturopathy, the 4th edition of Textbook of Natural Medicine by Joseph E. Pizzorno and Michael T. Murray with input from more than 90 other contributors. Pizzorno is President Emeritus of Bastyr University, the premier school of naturopathy, and Murray is on the Bastyr faculty. A 1,944-page tome, the Textbook’s list price is $252.00. It is advertised as “the gold standard in natural medicine,” and as a scientific presentation that “includes the science behind concepts and treatments, and discusses Western medical treatments and how they can work with natural medicine in a comprehensive treatment plan.” On the Amazon website it says “More than 10,000 research literature citations show that the content is based on science rather than opinions or anecdotes.”

Arnold Relman MD is Emeritus Professor of Medicine and of Social Medicine, Harvard Medical School and Editor-in-Chief Emeritus of The New England Journal of Medicine. In 2001, while serving as a representative to the Massachusetts Special Legislative Commission on Complementary and Alternative Medical Practitioners, he reported on an earlier edition of this textbook. His conclusion:

…the licensing of naturopathic medical practitioners as independent providers of primary health care would endanger the health and safety of the public and would not result in health benefits commensurate with its risks.

While some updates and minor improvements have been made, the 4th edition only confirms Relman’s opinion. In some respects, its content has gone downhill. This edition includes a whole new chapter on Unani medicine. More about that later. The book is divided into several sections. I’ll address each of them.

The Preface

At the very beginning, the Preface raises concerns. It claims that scientific support for naturopathy has evolved, and that it will cite 10,000 peer-reviewed research studies; yet in the next breath it lists homeopathy as one of the common modalities of natural medicine. This does not compute. The evidence does not show that homeopathy is effective for any condition; moreover, homeopathy is incompatible with our basic knowledge of physics, chemistry, and biology. It not only doesn’t work, it couldn’t possibly work. Homeopathy is fantasy, not science.

Section 1: Philosophy of Natural Medicine

Section 1 addresses the history and philosophy of natural medicine. It offers these seven fundamental principles of naturopathic medicine (which I have debunked before):

  1. The healing power of nature (vis medicatrix naturae)
  2. First do no harm (primum non nocere)
  3. Find the cause (tolle causam)
  4. Treat the whole person
  5. Preventive medicine
  6. Wellness
  7. Doctor as teacher

These are laudable principles, but (1) they don’t serve to distinguish between NDs and MDs because they are essentially the same principles that characterize the best conventional medicine, and (2) the rest of the book demonstrates that NDs don’t do a good job of following their own principles.

Also of concern: the introduction to this section introduces what will be a continuing theme, criticism of “the dominant school of medicine”. The first of many false accusations is that MDs have only a superficial understanding of health and disease. Ironically, the Textbook demonstrates that NDs have only a superficial understanding of what constitutes good science.

They assert that naturopathic medicine focuses on restoration of health rather than treatment of disease. Chronic disease arises when a disturbing factor persists (like a poor diet), the body’s reactive process is disturbed (usually by drugs) and the vitality of the system is insufficient or has become too overwhelmed to mount a sufficient reaction. NDs avoid suppression of symptoms and use unscientific terminology like “harmonize with your life force”.

Naturopathy embraces vitalism, the theory that the origin and phenomena of life are dependent on a force or principle distinct from purely chemical or physical forces. Vitalism has been refuted by empirical evidence and has been discarded by both scientists and philosophers – essentially by everyone except proponents of naturopathy and some other forms of alternative medicine.

The Textbook asserts that vitalism is based on observable scientific phenomena. It asserts that homeostasis, entropy, and evolution require vitalistic rather than mechanistic explanations. This is simply not true; it demonstrates their poor understanding of science.

They say the body’s self-healing mechanisms can be stimulated by constitutional hydrotherapy (alternating hot and cold towels), homeopathy, acupuncture, and “exposure to appropriate rhythms, patterns, and forces of nature”. Weakened organs can be supported by homeopathic medications that act “nutritively”, that stimulate specific organs and “detoxify” them (which is bunk). Weakened organs are also supported by organ-specific Qi Gong and yoga. They have no references to support these assertions, and this is not the language of science.

They say the approach of diagnosing and treating pathology is less satisfying than the naturopathic model of practice and “less productive of the most elegant outcomes and the long-term continued health of the patient”. They offer no references, and there is no evidence that this is true. I don’t know of any study comparing objective outcomes from treatment by NDs to treatment by MDs.

A chapter on placebos is very misleading. It misrepresents the power of the mind, asserting that intention has been observed to affect machines and remote biological systems. It interprets quantum physics to mean that it is impossible for a doctor to observe a patient without the observation’s affecting the health of the patient!

To illustrate the power of placebo, they gullibly accept unverified anecdotes from Third World countries as evidence of the power of taboos and curses to kill strong healthy men and women. To illustrate the power of prayer, they cite the Byrd study of intercessory prayer in a CCU as showing “a dramatic result”. It did not. It was a fatally flawed study that reached a conclusion not supported by the data. It measured 29 endpoints: 23 of them were negative, and the six that were positive were not independent variables. The authors of the Textbook fail to understand the problem of multiple endpoints and the need for statistical corrections. Throughout the book, there are many examples like this where they demonstrate their inability to distinguish between good and bad clinical studies, and they also unquestioningly accept poor studies that support their beliefs and make excuses for good studies that don’t.

They say the placebo response means healing. Placebos don’t produce healing in any objective sense: placebo responses are subjective. By definition, placebos have no objective therapeutic effect. They say the consciousness of the patient determines the effectiveness of any therapy. That is demonstrably untrue: antibiotics work just as well in unconscious patients.

Section 2: Supplementary Diagnostic Procedures

This section covers a number of tests described as “on the cutting edge of our understanding of the assessment of the physiologic function of metabolically unique individuals”. Some examples: apoptosis assessment, cell signaling analysis, hair mineral analysis, the rapid dark adaptation test, biomarkers for stool analysis, etc. It also covers some standard tests and advocates using them in non-standard ways. For instance, it says the erythrocyte sedimentation rate (ESR) is a marker for cancer, coronary artery disease, infection, etc. and it provides “invaluable feedback” on the effect of therapies for rheumatoid arthritis. Rheumatologists do not find it reliable when used alone; they have better methods of monitoring disease activity.

MDs don’t order these tests because they have not been shown to be clinically useful.

A section on food allergy testing includes bogus “Energetic Methods” such as Vega testing, applied kinesiology, electrodermal screening, etc. It correctly says that these tests are unreliable and not supported in the scientific literature; but then it says, “some practitioners have reported good success,” and “some practitioners may still find these techniques to be useful tools.” What are we to make of this? Aren’t they telling us to disregard science and rely on anecdote? How is this any different from saying “antibiotics don’t work for the common cold, but you might want to use them anyway”?

Section 3: Therapeutic Modalities

This section is damning. It shows that naturopathy is anything but scientific. The very fact that it includes a chapter on homeopathy is enough to discredit it, but there is much more that is worrisome. They explain,

Although this textbook is strongly oriented to the scientific method and the use of the peer-review literature for documentation of the efficacy of a therapy, these modalities’ widespread clinical use and long history of patient satisfaction demand that they be given a place here even though the mechanisms of action of several have yet to be elicited.

The logical fallacies here are glaring. Neither widespread use nor patient satisfaction are reliable guides to efficacy. Nor are they reasons that “demand” that unproven and disproven treatments be given a place in a science-oriented clinical practice or textbook. And when a modality has not been shown to work, or has been shown not to work, it is pointless to speculate about “how” it works. I will just comment on some of the 19 modalities that are presented in separate chapters.

Acupuncture is presented as an effective treatment modality. Qi, acupoints, and meridians are imaginary pre-scientific concepts with no basis in anatomy or physiology; yet here they are presented as facts. This chapter uncritically asserts things like “Rebellious Qi manifests as belching, burping, and vomiting, a reversal of the normal downward movement of Qi digestively”. This is mythology, not science. A rigorously scientific examination of the claims and evidence for acupuncture has led to the conclusion that it is a theatrical placebo. The chapter does not acknowledge such criticisms.

Ayurveda is presented in the chapter title as “The Science of Life and the Mother of the Healing Arts”. Like acupuncture, Ayurveda is a pre-scientific belief system. It is based on a religious philosophy of creation, and posits cosmic consciousness, five basic elements (ether, air, fire, water, and earth), three doshas (Vat, Pit, and Kaph) that allegedly control all biological, psychological, and physio-pathologic functions of the body, mind, and consciousness; and a lot of other imaginary nonsense. Ayurveda makes complicated diet recommendations based on these concepts, and it employs all sorts of natural remedies, only a few of which have been scientifically tested and shown to have some benefit. The book claims that Ayurveda has “a consistent and logical framework” and is “quite succinct and relevant to modern life”.

Botanical medicine was the foundation of modern pharmacognosy. Around half of today’s prescription drugs were developed from plants. The scientific approach is to identify the active ingredient, purify it, standardize it, synthesize it, and when possible, improve on it by developing a related compound that is more effective or has fewer side effects. Naturopathy wants to turn back the clock and return to whole plant derivatives. They disparagingly refer to active ingredients as “so-called” active ingredients. They insist that the FDA should not require the same standard of proof as for pharmaceuticals; they advocate a lesser standard of evidence for botanicals based on the advice of experts rather than on scientific studies. In my opinion, this makes no sense. A drug is a drug whether it is produced in a plant or a lab, and the same standards should apply to all.

They assert that “the mechanism of action of an herb often corrects the underlying cause of a disorder. In contrast, a synthetic drug is often designed to alleviate the symptom or effect without addressing the underlying cause.” They have no evidence to support that assertion, and it doesn’t even make sense.

They repeatedly claim that research has shown that the whole plant or crude extract is much more effective than isolated constituents. I don’t think that’s true, and they don’t offer any supportive references. The whole plant might contain a synergistic compound, but it might just as well contain a compound that acts against the active ingredient or that causes unwanted effects. And blanket statements are meaningless. Each plant must be tested against its active ingredient.

They say the advantages of herbal medicines are threefold: lower cost, fewer side effects, and medicinal effects that tend to normalize physiologic function. Using a less effective or ineffective medicine because it costs less is false economy. And if a medicine doesn’t have effects, of course it is less likely to have side effects. And there is no reason to expect that an herbal medicine would be more likely to normalize physiologic function than a synthetic medicine. And of course, they offer no supportive evidence for this claim, either.

They think the original use of plants as medicine was a result of “instinctive dowsing”. Animals instinctively eat plants that heal them, and presumably humans once possessed the same instinct but have now lost it. I doubt that.

The doctrine of signatures said that the appearance of a plant indicated its therapeutic use. One of the examples they give is that blue cohosh has branches arranged like limbs in spasm, indicating its usefulness as a treatment of muscular spasm. They assert that this use has been confirmed by recent research. The Natural Medicines Comprehensive Database disagrees. I have found the NMCD to be the most complete, most reliable, science-based source of information on natural medicines. They say there is insufficient reliable information about the effectiveness of blue cohosh for any use, and they rate it as “likely unsafe.”

Environmental Medicine is a questionable area that they accept without question. They assume multiple chemical sensitivity (MCS) is real. MCS is not recognized by any reputable professional medical organization. They exaggerate the importance of environmental exposures, even suggesting that they are the underlying cause of diabetes. For this claim and others, they rely on flawed studies that showed correlations but did not establish a causal relationship. For treating presumed chemically-induced illnesses, they recommend avoidance, dietary support, nutritional supplementation, and depuration.

Depuration, or cleansing, can supposedly be accomplished by rice bran fiber and by chlorophyll, a “blood purifier,” as well as by fasting and saunas. They say this is supported by the literature, but the published studies are all in rats, not humans. They cite Scientology’s “Hubbard Purification Rundown” and unpublished information from William Rea’s Environmental Health Center. Neither Scientology nor Rea are reliable sources. For fasting, they admit that there is only one published study where fasting reduced symptoms – but it raised the level of toxins in the blood. The author of this chapter offers his own comprehensive Crinnion Depuration Protocol for treating environmentally poisoned individuals. It consists of exercise, saunas, constitutional hydrotherapy (alternating hot and cold towels with sine wave stimulation), colonic irrigation, constitutional homeopathy (said to be most beneficial for individuals who need a boost for their vital force or who are stuck in emotional issues), body therapies (massage, Shiatsu, craniosacral, visceral, chiropractic), and counselling. He claims an 83% success rate overall, and a 100% success rate for several chief complaints. But this is his own report of his own series of patients; he has not published anything about it and has not done any controlled studies. Crinnion is asking his patients to follow a complicated, onerous protocol based only on the skimpiest preclinical evidence and his own anecdotal experience.

Homeopathy is covered in a long chapter that repeats the usual flawed arguments for homeopathy. These have been adequately rebutted elsewhere. While positive studies do exist, the scientific consensus based on the totality of published evidence is that homeopathy is not effective for anything. The chapter insists that it is effective and says, “Homeopathy is representative of a principle found throughout nature and its role in bringing forth concepts of resonance, constitution, and holism are shared throughout fields of science and healing”. If this means anything, it is not science.

Nontransfusion Significance of ABO and ABO-Associated Polymorphisms is a chapter that endorses D’Adamo’s Blood Type Diet, citing popular books and self-reported consumer satisfaction. It does not see fit to mention that a recent systematic review of the published studies concluded that no evidence exists to support benefits of blood type diets. Its conclusion that ABO blood types are “worth factoring into the everyday algorithms of a nutritional practice” is not justified.

Nutritional Medicine includes this: “The recommendation to drink at least 48 oz of water per day is valid.” It is not. That is a myth that has been debunked too many times to count.

Peat Therapeutics and Balneotherapy was something new to me. The author recommends peat therapy for a variety of conditions including arthritis, headache, ankle sprain, hypertension, scleroderma, herpes, HPV, infertility, and immune stimulation. His evidence is mostly anecdotal, and it’s not clear that peat has any significant advantage over other mud pack and mud bath treatments. A Cochrane review of balneotherapy for rheumatoid arthritis concluded:

Overall evidence is insufficient to show that balneotherapy is more effective than no treatment, that one type of bath is more effective than another or that one type of bath is more effective than mudpacks, exercise or relaxation therapy.

Spirituality and Healing is covered in a long chapter whose language is more appropriate to a religious service than to a scientific treatise. They call illness “the gift of spiritual healing”. They repeat bogus claims about the non-local activity of consciousness. Consciousness is recognized by science to be an emergent property of the brain. There is no evidence that it can exist outside the brain or have non-local effects.

They uncritically describe studies that have been discredited elsewhere for their fatal methodological flaws. They claim that “a substantial body of research published in diverse journals documents the efficacy of faith and prayer, both for those praying and those prayed for, in longevity, recovery from surgery, prevention of disease, and improvement in lifestyle and behaviors.” Others have examined that body of research and reached this very different conclusion:

Prayer has been reported to improve outcomes in human as well as nonhuman species, to have no effect on outcomes, to worsen outcomes and to have retrospective healing effects. For a multitude of reasons, research on the healing effects of prayer is riddled with assumptions, challenges and contradictions that make the subject a scientific and religious minefield. We believe that the research has led nowhere, and that future research, if any, will forever be constrained by the scientific limitations that we outline.

Unani Medicine is one of the most disturbing chapters to me. The ancient Greek concept of the four humors might deserve a brief historical footnote as representing medicine’s earliest fumbling towards understanding illness. What it does not deserve is a long chapter explaining how Greek thought was perpetuated in the Arab world and persists today as the system of Unani medicine. Surely there is no need for the 21st century healthcare provider to learn the details of ancient descriptions of the four humors, for instance that an individual with a phlegmatic temperament is cold and wet, with a round face, heavy frame, light hair, a pale complexion, slow digestion, and inefficient kidneys, with “metabolic water drowning out metabolic fire,” etc. Or that an individual with a choleric temperament is hot and dry, with a broad jaw, curly hair, a sharp appetite, scanty dark urine, violent dreams, etc. etc. More than two full pages are devoted to lists of such details.

The author says:

This gift from the East, along with Ayurveda and Traditional Chinese Medicine – will reveal itself to serious seekers as a very real health care option offering natural, safe, and effective approaches to healing.

That’s his opinion, but it’s not science. The effectiveness of those approaches is not substantiated by the evidence, and superstition and religion do not belong in a modern medical textbook. Jann Bellamy has extensively criticized this chapter. She comments, “there is no richer source for argument against CAM practices than the CAM literature itself. And this is a perfect example”.

Section 4: Syndromes and Special Topics

The introduction to this section offers a big insight into naturopathic thinking. “Careful study of the various diseases to which humans are heir indicates that a limited number of underlying problems either cause or significantly contribute to most diseases.” Poor diet + unhealthy lifestyle + toxin exposure leads to nutritional deficiencies and toxicity which leads (in the context of genetic susceptibility) to metabolic dysfunction + subacute disease, which leads to clinically recognizable diseases that are apparently unrelated to the underlying causes. In other words, they believe that there is essentially one underlying cause of disease; that diet, lifestyle, and toxin avoidance can prevent most disease; and that correction of those factors can cure existing diseases. That’s what they say, but then they find it necessary to also throw a whole slew of dietary supplements and botanicals at every problem.

These beliefs are immediately undermined in the first chapter in this section, on cancer, which reveals, “When the author first began to learn more about the actions of natural agents and cancer cells, he became optimistic that with the proper combination of agents, most patients would need little or no conventional therapy. Unfortunately, despite a few remarkable successes, for the majority of patients, natural therapies alone were unable to completely control the disease process”. That doesn’t stop him from recommending melatonin and green tea to improve the effectiveness of conventional cancer treatments and all sorts of other natural remedies to use along with chemotherapy and radiation – with no supporting evidence that they affect patient outcomes.

Chronic candidiasis is a fake illness that nevertheless gets its own chapter. They believe it is real. They even offer an unvalidated Candida Questionnaire in an Appendix, where you can answer a series of questions to determine the likelihood that you have the disease. They pontificate about its causes, diagnosis, and treatment, recommending a complex regimen of tests, diet, dietary supplements (propolis, tea tree oil, garlic, berberine, and much more), probiotics, detoxification, and promoting a positive mental attitude. This is all nonsense, since chronic candidiasis doesn’t exist.

Homocysteine is covered in great detail. They demonstrate how to lower homocysteine levels with natural remedies but finally have to admit that there is no evidence that lowering homocysteine levels has any impact on actual health outcomes.

Immune support is covered in a chapter that allegedly shows how to reactivate and support the immune system with lifestyle, supplements, nutrients, botanicals, and promoting optimal thymus gland activity. The need for all this is not substantiated by good scientific evidence, and there are no good studies showing that such treatment produces better clinical outcomes.

Detoxification doesn’t get a chapter of its own, but it is mentioned repeatedly here and elsewhere throughout the book. It is a favorite trope of alternative medicine practitioners who offer all kinds of detoxification diets, supplements, and other treatments. Except in special cases like alcohol withdrawal and heavy metal poisoning, the idea that we need “detoxification” is a myth. The body has its own detox system that works very well without any outside help.

Other topics in this section include dietary fiber, “functional” toxicology, hyperventilation syndrome, intestinal protozoan infestations, maldigestion, sports nutrition, and stress management.

Section 5: Pharmacology of Natural Medicines

They say this section is intended to revive the appreciation for botanical medicines and to promote the use of whole plants rather than isolated active ingredients. It stresses that botanical medicine should not be used simply as a substitute for the drugs commonly used to treat disease; but should be used along with them, to remove the causes of disease and promote health, always with awareness of possible interactions. Eighty botanicals are covered in individual chapters. A few examples will illustrate the general pattern of the entries.

Sarsaparilla will serve as a good example of the textbook’s questionable fact-checking and its willingness to accept inadequate evidence. In a section on the history of botanical medicine, it says syphilis was responsible for opening the door to new herbs from the Americas and contributing to herbal medicine’s displacing Galenical medicine. It says in 1812, Portuguese soldiers suffering from syphilis who used sarsaparilla recovered much faster and more completely than their British counterparts who were treated with mercury. (Not surprising, since mercury is so toxic.) Despite the initial enthusiasm, the sarsaparilla treatment fell into disfavor, probably because the cure also required confinement to a warm room for 30 days followed by 40 days of abstinence from both wine and sexual intercourse. It says clinical observations and blood tests in China demonstrated that sarsaparilla is effective in about 90% of cases of acute syphilis and 50% of cases of chronic syphilis. I find that very hard to believe! That chapter does not provide references for those claims, but a later chapter on Sarsaparilla does. It references a 1996 encyclopedia of common natural ingredients used in food, drugs and cosmetics, a 1981 history of herbal medicine, and a 1986 book on Chinese herbal medicine. I have no access to those books, so I can’t check where those books got their information. I couldn’t find any confirmation on the Internet.

The chapter on Sarsaparilla attributes sarsaparilla’s medicinal action to its binding of bacterial endotoxins in the gut, which reduces absorption, “greatly reduces the stress on the liver and other organs”, and is “probably the reason that sarsaparilla is effective in many cases of psoriasis, gout, and arthritis.” In a later chapter on psoriasis, they say individuals with psoriasis have been shown to have high levels of circulating endotoxins. I could only find one reference to support that: a 1982 study of a mere 11 patients with psoriasis. As evidence for the effectiveness of sarsaparilla, they cite a single 1942 study from The New England Journal of Medicine, volume 337: 128-133. They got the citation wrong: the study was in volume 227. After considerable sleuthing, I was finally able to track it down. It is best categorized as a preliminary or pilot study, the kind of study that requires further investigation before the treatment can be recommended for clinical practice. It studied one specific sarsaparilla compound, sarsasaponin, so its results may not apply to the sarsaparilla remedies available today. There were 75 subjects and 17 controls. Various topical treatments were used concomitantly. The study was not blinded, not randomized, and not placebo-controlled. There are no entries in PubMed or Google Scholar for sarsasaponin. There has been no replication or follow-up in all the decades since 1942. Pretty thin gruel, indeed.

The Natural Medicines Comprehensive Database says, “There is insufficient reliable information available about the effectiveness of sarsaparilla”. The Textbook says no adverse effects have been reported, but the NMCD says GI irritation and temporary kidney impairment have been reported. Curiously, the NMCD’s reference for side effects is the same 1996 encyclopedia referenced by the Textbook. They both read the same reference but disagreed about what it said.

In the chapter on Psoriasis, it recommends sarsaparilla along with goldenseal “if indicated by impaired digestion or liver function”. Why do they recommend goldenseal? The Natural Medicines Comprehensive Database says there is “insufficient reliable information about its effectiveness” for any indication, and the Textbook doesn’t even mention it in its section on the pharmacology of natural medicines.

Allium cepa (onion) is an example of “let food be your medicine”. They say onions have antimicrobial activity, cardiovascular effects, hypoglycemic action, anti-asthmatic action, antitumor effects, and hair tonic effects. They offer only a few published studies dating as far back as 1969. They recommend its use in cardiovascular disease, diabetes mellitus, and inflammatory conditions, at a therapeutic dosage of 50 to 150 g/day of raw onion. They offer no evidence showing meaningful clinical benefits from adding it to the conventional treatments for those conditions. The Natural Medicines Comprehensive Database lists onion as “possibly effective” when applied topically for scarring, and “insufficient reliable evidence to rate” for alopecia, diabetes, hypertension, or any other use.

Artemisia absinthium (Wormwood) is claimed to have digestive, hepatic, anti-parasitic, and neurologic effects. They cite a few preliminary studies, uncontrolled trials, and one randomized, double-blind clinical trial in Crohn’s disease that found it more effective than placebo. The NMCD entry on wormwood says there is “insufficient reliable evidence to rate” for effectiveness for Crohn’s disease or IgA nephropathy, and it doesn’t even address any other use.

Bromelain, according to the Textbook, has been “proven effective” for angina, arthritis, athletic injuries, bronchitis, burn debridement, cancer, cellulitis, circulatory disorders, dermatologic conditions, digestive disorders, dysmenorrhea, ecchymosis, edema, infections, pancreatic insufficiency, phytobezoar, pneumonia, scleroderma, sinusitis, staphlococcal [sic] infection, surgical trauma, and thrombophlebitis. The Natural Medicines Comprehensive Database looked at the same evidence and came to the conclusion that bromelain is “possibly ineffective” for exercise-induced muscle soreness and that there is insufficient reliable evidence to rate its effectiveness for any other condition.

The pattern of these entries can be seen in these examples. They pick a natural medicine and describe everything that is known about its function. They search the literature for anything and everything they can find. Animal studies, test-tube studies, irrelevant studies, preliminary and pilot studies that have never been replicated or followed up, uncontrolled studies, methodologically flawed studies: it’s all “evidence” to them. In contrast, the Natural Medicines Comprehensive Database has a more rigorous scientific concept of evidence and finds that most of the studies listed in the Textbook amount to “insufficient reliable evidence to rate” the effectiveness of the remedy. Once they have identified their “evidence”, the Textbook speculates that the natural medicine “might” have some benefits for human illnesses, and recommends trying it along with other speculative remedies. They are usually unable to cite the kind of randomized, placebo-controlled studies that might be able to determine whether their recommendations are valid. All in all, the chapters in this section serve as an excuse for NDs to try anything they imagine “might” help, and to make things up as they go along. Their patients are essentially being used as guinea pigs in an uncontrolled, unmonitored experiment. I doubt whether their patients realize this; whatever happened to informed consent?

Section 6: Specific Health Problems

The Textbook authors are conflicted about this section. They offer it as a useful guide to the origins and causes of disease and as a therapeutic handbook. But they are concerned that it might “promote the disease orientation of the current dominant medical system”. They remind readers to always treat the patient, not the disease; and to consider the psychological and spiritual reasons people may have for being sick.

In this section, they claim to find the cause of a disease when they are really only identifying all the possible risk factors. We see the same pattern here that we saw for natural medicines: they scour the literature to find any study that might conceivably have some relevance; and they offer multiple recommendations for supplements, botanicals, and other treatments based only on the skimpiest evidence and the personal opinions of the authors. They frequently include acupuncture and homeopathy in their recommendations, treatments that have not been proven to work and that have been proven not to work. Some of the advice they give is potentially dangerous, and there are glaring omissions. I will just make a few comments on things that jumped out at me.

Acne. Despite their claim to cover “Western medical treatments and how they can work with natural medicine in a comprehensive treatment plan”, the entry on acne mentions effective conventional treatments only to dismiss them. They say, “Success can be obtained only by the rigorous, comprehensive application of dietary, nutritional, and botanical interventions.” Dermatologists would disagree; they treat acne successfully without such interventions, relying instead on over-the-counter and prescription medications and other measures that have been tested and proven to work. Instead, the Textbook recommends eliminating various foods from the diet, taking seven dietary supplements, using physical measures like light, and using five topical treatments including daily washing with calendula soap (no supporting references). They recommend tea tree oil even though elsewhere the Textbook reports a study showing tea tree oil was less effective for acne than conventional treatment with benzoyl peroxide. Far from demanding scientific evidence, they are content with testimonials (“In the author’s experience, vitamin A 150,000 IU daily in an emulsified form has prove [sic] to be a reliable and safe means of bringing acne under control.”) Note: that amount of vitamin A is well above the Tolerable Upper Intake Level.

Asthma attacks can kill. The Textbook recognizes this, but it gives dangerous advice. It says, “If intravenous magnesium cannot be administered, the patient should be referred to an emergency department immediately”. Intravenous magnesium is used in treating an acute asthma attack treatment only as an adjunct to conventional treatment. Treating the patient with IV magnesium before or instead of referral to an ED could have fatal results.

Atherosclerosis. Here they acknowledge that statin drugs are the mainstay of treatment. They offer the standard recommendations of conventional medicine to reduce risk factors, but they indulge in speculation about botanical remedies and they recommend supplements that are not supported by good evidence.

Cervical dysplasia. Astoundingly, they manage to spend 8 pages on cervical dysplasia without once mentioning the HPV vaccine, which is the most effective way to prevent this disease. They recommend dietary measures, 10 nutritional supplements, and green tea extract. They recommend escharotic treatment instead of LEEP (the Loop Electrosurgical Excision Procedure), without divulging that LEEP has the valuable advantage of providing tissue samples to determine whether the lesion has been completely removed. They recommend a “vag pack” to apply various botanical remedies via tampon. They admit that no controlled studies of its clinical efficacy have been published, but “it has a long, and apparently successful, history of use”. So did bloodletting to balance the humors.

Cataracts. They acknowledge that surgery is usually needed, but they think cataracts can be prevented with diet, eight supplements, and two botanical medicines (no supporting studies). They helpfully advise that “Patients should avoid rancid foods”.

D-mannose for cystitis. “Although there are no clinical trials available to support the use of D-mannose powder, a handful of research articles explaining its function strongly support its use”. No, explaining function does not support use, not even weakly. This is purely wishful thinking.

Diabetes. They don’t make it clear that insulin is essential for Type 1 diabetes. They don’t provide any guidance about insulin therapy or the oral hypoglycemic drugs that have been proven effective. Instead, they mix conventional diet and lifestyle recommendations with unconventional recommendations for meditation, ear acupuncture, and a long list of dietary supplements and botanical medicines that may help reduce blood glucose but won’t control it as effectively as conventional treatment.

Epilepsy. They don’t even mention the drugs that have been proven to control seizures except to say, “epileptic patients who are not controlled with natural therapies require drug therapy”.

Hepatitis B. They acknowledge the value of the Hep B vaccine, but fail to recommend its use in all newborns, instead recommending it only if the mother tests positive. Early protection is essential because the younger the age, the greater the risk that hepatitis B will persist as a chronic infection that leads to liver cancer and death later in life. They claim to emphasize prevention, but here they are rejecting a valuable, proven preventive measure, denying it to the most vulnerable patients who would benefit the most.

HIV/AIDS. This chapter properly recommends referral to a specialist for conventional treatment with anti-retroviral drugs. But it also recommends supplementing the drugs with natural medicines and diet, and it recommends acupuncture and homeopathy. It says, “The use of constitutional homeopathy should be considered an essential aspect of the care of all HIV+ patients considering the amazing potential, minimal side effects, and overall affordability”. That’s nonsense.

Hypertension. Relman criticized the earlier edition for saying nothing about the diagnostic workup needed to rule out curable causes of high blood pressure. This new edition still doesn’t mention it. A particularly glaring omission when one of naturopathy’s main principles is to find the underlying cause.

Other omissions. There are many other omissions. For instance, there is no mention of arrhythmias or the need for anticoagulants to prevent stroke in patients with atrial fibrillation. Sexually transmitted diseases are not covered. There is no mention of opioids, an essential treatment for intractable pain. Students relying on the Textbook will not learn about many things they need to know to care for patients, to recognize serious illnesses, and to ensure that essential conventional treatments are being used.

Hyperthyroidism. A statement in this chapter directly contradicts naturopathy’s claim to not just treat symptoms. For Graves’ disease, “Mild cases should be treated symptomatically”.

Hypoglycemia. “A strong yet controversial link exists between hypoglycemia and aggressive or criminal behavior”. No, if it were strong it wouldn’t be controversial.

Hypothyroidism. “Invigorating activity such as water sports, avoidance of overheated environments, and cold hydrotherapy can stimulate thyroid function”. Really? The only reference supplied for that claim is a 2001 book published by the author. (“It’s true because I say it’s true”?)

Infectious diarrhea. The section on Rotavirus fails to mention that we now have a safe, effective vaccine to prevent it. It says infectious diarrhea can be prevented by avoiding undercooked meat or seafood, unpasteurized milk, or soft cheese. It doesn’t mention the standard recommendations for travelers to avoid tap water, ice, salads and other raw vegetables, fruits that can’t be peeled on the spot, etc.

Migraine. Recommendations include “Acupuncture to balance the meridians”. Meridians don’t exist.

Streptococcal pharyngitis. They downplay the complications of strep throat and the need for antibiotics, mentioning rheumatic fever and glomerulonephritis only to say “the attack rates after a streptococcal infection are 0.4% to 2.8% for rheumatic fever and 0.2% to 20% for glomerulonephritis. Obviously such a wide range of reported sequelae makes accurate evaluation of the risk difficult”. It may be difficult to quantify the true incidence, but it is crystal clear that the risk is real. And they don’t mention other sequelae of strep throat such as meningitis, pneumonia, toxic shock syndrome, and peritonsillar abscess.

Enough is enough! I have provided enough examples to show a consistent pattern. There are similar problems with almost every chapter of the Textbook.


A number of egregious errors were overlooked by the editors and proofreaders. A table of Common Illness Mediators lists electrons and ions under the category Subatomic. Ions are not subatomic. References are sloppy: for example, the reference for a study on aloe vera for dandruff is actually a study of the topical application of pyridoxine ointment.

Chapter 6 repeatedly uses prima non nocerum for primum non nocere and tollem causum for tolle causam. And these are the names of two of their seven basic principles!

The section on condylomas gets everything backwards. Condyloma lata is a manifestation of syphilis. The Textbook says it is caused by human papillomavirus (HPV). It is not. Condyloma acuminata (venereal warts) are caused by the HPV virus, but in the section on condyloma acuminata they don’t mention that, and they don’t mention that the great majority of these genital warts can be prevented by the HPV vaccine. So much for their alleged emphasis on prevention!

Conclusion: Not good science

It is hard for me to fathom how such a textbook could exist in the 21st century and how anyone could characterize it as scientific. Despite the plentiful citations, the content is a bizarre, uneven potpourri of good science, bad science, pseudoscience, vitalism, philosophy, ancient history, superstition, gullibility, misrepresentations, metaphysics, religion, hearsay, opinion, and anecdotes. (Note: I used the word potpourri intentionally; its original meaning in French was rotten pot.) Right alongside good conventional evidence-based medical information and advice, it recommends using treatments that are purely speculative and even treatments have been proven not to work. It is a travesty. If this is what NDs are taught, if this is what NDs believe, they are deluding themselves and doing their patients a disservice.

Revisiting the 7 principles:

  1. The healing power of nature (vis medicatrix naturae): MDs recognize that the body has well-understood real physiologic processes that produce healing, that doctors don’t heal the body but provide measures that allow the body to heal itself. NDs believe in an imaginary vitalistic force that heals.
  2. First do no harm (primum non nocere): This doesn’t mean never do anything that might possibly be harmful; it means be sure a treatment is more likely to help than to harm. Most of the remedies recommended in the Textbook have not been adequately studied. We don’t know if there is any risk of harm, and even a hypothetical risk is not justified if there are no real benefits.
  3. Find the cause (tolle causam): MDs find and treat the real underlying cause whenever possible. NDs find risk factors, hypothetical causes, imaginary causes, and nonexistent diseases. They believe that poor diet + unhealthy lifestyle + toxin exposure underlies most chronic illnesses.
  4. Treat the whole person: MDs are taught to treat the whole person, to take a complete history with a review of systems and an evaluation of psychosocial factors that might have an impact on the illness or its treatment. NDs do that but also address imaginary aspects of the “whole” person, like acupuncture meridians, qi balance, and universal consciousness.
  5. Preventive medicine: MDs invented preventive medicine; they offer effective prevention based on evidence. NDs offer all sorts of preventive measures whose effectiveness has not been established, and they omit many proven conventional preventive measures like HPV vaccines.
  6. Wellness: How do you measure wellness? Does naturopathy really do a good job of promoting it? Or do they just load healthy people up with a lot of supplements they don’t need and complicate their lives with other recommendations?
  7. Doctor as teacher: MDs share their scientific knowledge with their patients; NDs do that, but they also teach them about speculative and imaginary ideas and make claims that are not supported by acceptable evidence.

In short, the things that NDs do that are good are no different from what good MDs do; and the things they do that are different are not good.

I suspect if the legislators who voted to license NDs and the patients who chose to consult NDs rather than MDs had been aware of the serious problems with the naturopathic approach that are demonstrated by this Textbook, they might have had second thoughts. I like to think that they would have.



  • Harriet Hall, MD also known as The SkepDoc, is a retired family physician who writes about pseudoscience and questionable medical practices. She received her BA and MD from the University of Washington, did her internship in the Air Force (the second female ever to do so),  and was the first female graduate of the Air Force family practice residency at Eglin Air Force Base. During a long career as an Air Force physician, she held various positions from flight surgeon to DBMS (Director of Base Medical Services) and did everything from delivering babies to taking the controls of a B-52. She retired with the rank of Colonel.  In 2008 she published her memoirs, Women Aren't Supposed to Fly.

Posted by Harriet Hall

Harriet Hall, MD also known as The SkepDoc, is a retired family physician who writes about pseudoscience and questionable medical practices. She received her BA and MD from the University of Washington, did her internship in the Air Force (the second female ever to do so),  and was the first female graduate of the Air Force family practice residency at Eglin Air Force Base. During a long career as an Air Force physician, she held various positions from flight surgeon to DBMS (Director of Base Medical Services) and did everything from delivering babies to taking the controls of a B-52. She retired with the rank of Colonel.  In 2008 she published her memoirs, Women Aren't Supposed to Fly.