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CAM Conversion–From Skeptic to Believer

Posted on September 4, 2011 by skeptvet

I frequently find that advocates of alternative medicine present themselves as converted skeptics. Of course, many came to veterinary medicine with a preconception that alternative methods were beneficial. But quite a few veterinarians or MDs who promote alternative methods tell stories about coming from a position of doubt or even outright antagonism towards unconventional practices to a position of strong belief.

These narratives have the effect of establishing the doctor’s credentials as a hard-nosed, critical thinker, which presumably makes the methods they are selling seem more legitimate. Such “spin” is necessary only because many people recognize that some alternative practices are highly implausible and require an element of faith without evidence to accept. So promoters of such methods wish to present themselves not as excessively credulous but as skeptics won over by the undeniable strength of the evidence.

I have no doubt that these folks tell these narratives honestly. I am fairly sure they are genuine, though I am less convinced they are accurate. It is clear from extensive research in psychology that such biographical narratives, and human memory in general, are seldom accurate factual reproductions of the past. Rather, they are stories continuously revised to fit into the current structure of our beliefs about the world and ourselves (for more detail, see Don’t Believe Everything You Think, On Being Certain, and Mistakes Were Made: But Not By Me). Neat parables about one’s conversion from skeptic to believer seem a perfect example of how such unconscious revisionism sevres to reinforce our beliefs and self-concept.

Such conversion stories are remarkably consistent thematically, though of course there is variation in the details. Often, the practitioner relates how they initially practiced conventional medicine but became frustrated by the limitations of scientific care. They also frequently describe miraculous individual cases, or even experiences involving their own health, that convinced them there was real validity to alternative methods.

Obviously, there are diseases we don’t understand and cannot treat very effectively, and it is natural for any caring doctor to be frustrated by suffering they cannot relieve or illness they cannot prevent. Unfortunately, this understandable emotion born out of compassion and empathy becomes harmful when it leads us away from a sound, scientific pursuit of better understanding and interventions and towards a comforting but mistaken faith in unproven, ineffective, or even entirely magical treatments. And while individual experiences are very psychologically compelling, they are not reliable as proof that a therapy is safe or effective. So if they lead us to believe that ineffective practices work, they may be relieving our frustration while not actually doing a better job of treating our patients.

This example of such a conversion narrative illustrates both the frustration with the limitations of medicine and also the experience of having come to believe in alternative therapies through a perceived benefit for one’s own health. Since the conversion was to a belief in homeopathy, which is about as magical and unscientific a therapy as one can find, it is also a clear example of how one can be mislead by emotion and experience into rejecting useful practices for useless ones.

“Homeopathy is one of the rare medical approaches which carries no penalties – only benefits”
— Yehudi Menuhin, Violinist

Yehudi Menuhin’s statement reflects an important reason that I became interested in homeopathy. After practicing traditional Western medicine for roughly ten years, I became disenchanted with chemical drugs as being the only approach in dealing with disease. I was frustrated with the lack of effective treatments for chronic disease, behavior problems, and the epidemic of allergic conditions. During my search for alternatives, my personal health was greatly improved with homeopathic treatment, leading me to the study of homeopathy and the incorporation of this great system of medicine in my veterinary practice.

These stories often have an implicit, or even explicit, religious tone to them, illustrating an opening of the mind to realms of healing beyond the physical body, which is where medicine traditional directs its efforts. For example:

[I] practiced traditional veterinary medicine for 16 years. Gradually I became frustrated at the limitations of these methods and went abroad to Europe and South America to study healing methods practiced by holistic medical doctors. I incorporated these methods of natural healing in my own practice and found I could do so much more for my sick and painful patients… Why? It has to do with the philosophy, cause and effect of the two different methods of diagnosis and treatment of the patient…

Cure CANNOT be achieved in the physical body alone. Cure cannot be achieved by focusing on symptoms but on CAUSE, the true nature of symptoms exhibited. It is as if there is a dirty spot on a lens of a slide projector that is projecting an image on a screen. The traditional doctor works away on scrubbing the spot off the screen, while the holistic doctor cleans the lens, the cause of the spot on the screen…

Holistic medicine benefits Body, Mind (Emotional) and Spirit and recognizes these are also interdependent in maintaining health. Traditional medicine mainly concentrates on the body.

Some of these conversion stories do claim that the transition from skeptic to believer was brought about by thoughtful consideration of real scientific evidence. Here is one example. It manages to read like a pure religious conversion, with a series of miracle stories and even fainting brought on by the power of the revealed truth, and yet it claims to be an awakening based on a scientific approach to knowledge:

Before I knew about integrative medicine, it was easy to tell someone that nothing else could be done… There was truth in the statement and in knowing that “we had done everything we could,” but there was also sadness and loss in the failure that burned quietly at the core of my being.

In the 80s a series of crazy life changing events lead me to discover something wonderful.

… a mutual friend told me that her lovely Golden retriever had lymphoid cancer and she was being ripped off by a “quack alternative medicine doctor…” I decided that this “quack” should not be practicing and became determined to end his professional career.

I flew to New York to spend a week investigating the doctor, and found things that literally made me faint… I simply passed out rather than face the fact that the man I thought was a crook was actually a gifted healer…

One of the “snake oils” used to treat that dog for cancer was a mixture called Poly-MVA… After 30 years of testing over 20,000 products, Dr Garnett discovered Poly-MVA. His discovery created an entirely new field called electrogenetics, which is the study of electrical activity on the DNA. Poly-MVA appears to shuttle electrons in such a way that the susceptible cancer cells die while normal cells continue to survive.

… Gradually, scientific investigators began looking at Poly-MVA… The first major clinical veterinary study of its kind looked at 800 animals treated for various cancers and showed a clear improvement in quality of life.

…I began my quest into integrative medicine so many years ago to prove that this substance was quackery because I “knew” that there was no such solution. Through my scientific training and through common sense investigation, we found that it was useful and began treating patients with Poly-MVA over 15 years before further study demonstrated its usefulness. And now through proper scientific method, we are understanding that the dose needs to be further evaluated.

This narrative represents a skeptic as one who arrogantly rejects ideas they know nothing about. It illustrates how watching seemingly miraculous events should convince the open-minded skeptic that the things they believe are nonsense are actually true. And it claims that 15 years after seeing the truth, the revelation has been validated by science.

Unfortunately, skeptics are not those who judge things as false based on ignorance, but those who reserve judgment until reliable, scientific evidence is provided. Anecdotes, testimonials, and individual “miracles” do not constitute such evidence, because they are frequently misleading. And in this particular case, Poly-MVA is still an unproven nostrum based on questionable theory and without sound scientific validation.

Here’s what the American Cancer Society says about Poly-MVA:

Available scientific evidence does not support claims that Poly-MVA is effective in preventing or treating cancer….reports of Poly-MVA’s effectiveness are anecdotal or small studies that have not been confirmed or published in scientific journals.

No studies of Poly-MVA in humans have been published in peer-reviewed medical journals...

The potential risks and side effects of Poly-MVA are not known, as no results from human studies have been reported. Palladium compounds have the potential to cause allergic reactions in some people. Because lipoic acid is a powerful antioxidant, Poly-MVA may make radiation therapy or chemotherapy less effective. While this concern is based largely on theories of how cancer treatments work, it is supported by some recent studies.

And here’s a comment from Dr. Andrew Weil, who certainly cannot be accused of not being open-minded and friendly to alternative medical therapies:

I have seen no scientific evidence demonstrating that Poly-MVA either prevents or effectively treats cancer. Indeed, I have found no reports of any well-controlled scientific studies. Most of the “success stories” cited by promoters are simple testimonials or come from studies that have not been published in scientific journals. Poly-MVA may not be dangerous in and of itself, but when you’re dealing with a life-threatening illness such as cancer, it is always ill advised to substitute an unproven treatment for one that has been scientifically demonstrated to help. At best, Poly-MVA would do no harm. At worst, by using it as an alternative cancer treatment you could lose valuable time that might be better spent fighting the disease with therapy that has some medical merit.

Poly-MVA may or may not have benefits in cancer patients. At this point, no one really knows since there are no controlled research studies on the question. If poly-mva played a role in converting this doctor from a skeptic to a believer in the promise of alternative medicine, it is not because the scientific evidence proved his skepticism unfounded.

Obviously, people do sometimes experience profound shifts in their world view. And there is nothing inherently wrong with sharing these experiences with others. However, these medical conversion stories are frequently held up as examples of the flaws of science and skepticism and as paradigms for how a skeptic should, if they are really open-minded, become a believer in some deeper and more effective approach to medicine simply because of a few seemingly miraculous cases. They make nonsense seem scientific and legitimate and rejection of nonsense seem dogmatic and closed-minded. And they are ultimately examples of circular logic since they only make sense if we accept that “truth” discovered by the storyteller is actually true, which it often is not.

Posted in General | 2 Comments

Celebrate (or Mourn?) National Holistic Pets Day

Posted on August 31, 2011 by skeptvet

Oops, looks like I just missed the party! Apparently, yesterday was National Holistic Pets Day. This holiday was created by Colleen Paige… I was going to give a brief description of who exactly Ms. Paige is, but I don’t think I can. Her website describes her this way:

Colleen Paige is one of America’s premier Family & Pet Lifestyle Experts…She is also an Animal Behaviorist, Best Selling Author, Interior Designer for both people and pets, Artist, Gourmet Cook, Beauty Expert, former Paramedic, Child & Pet Safety Expert, Family Crisis Counselor, Wellness Aficionado and Publisher of Pet Home and Style & Bliss Magazines.

Wow! She also apparently likes to create holidays, usually to raise awareness and money for some animal-related cause; 19 holidays according to her foundation website. She sounds like a remarkable person, and browsing through her various web sites, I am impressed by her energy, creativity, and the depth of her commitment to her vision of animal welfare. She is undoubtedly doing a lot of good things for pets and people.

Unfortunately, as is so often the case, sincerity and a commitment to doing what is best for pets don’t always correspond with a deep or accurate understanding of what actually is best, at least in the area of healthcare. Her description of National Holistic Pets Day includes all too many of the usual myths and misconceptions and fuzzy thinking that characterize the meaningless buzzword “holistic.” Ms. Paige dedicates this holiday to a companion she lost to cancer, and her description of the experience is both touching and representative of the mixed up thinking behind the idea of holistic medicine:

After the Feb. 2010 death of my fur child Tinkerbelle, from a brain tumor…I began to think about her diet and health regimen and wondered if somehow I could have done better in terms of her health care. I gave her filtered water, fresh filtered air at home and only all-natural food and treats void of corn, wheat, sugar and chemicals.

I didn’t however, give her vitamins and supplements. Could the addition of these have fought against free radicals and other toxins in her body that caused this tumor? Maybe, maybe not, but it made me really uneasy to know that there were other things I could have done that would have at least left me with the surety that I did everything I could.

Already committed to the belief that illness is caused by mysterious “toxins,” despite the lack of evidence for most specific chemical suspected to be harmful and ignoring the role of genes, age, and simple random bad luck, Ms. Paige followed many “holistic,” and completely pointless, guidelines in trying to protect her pet from “this overly toxic world we live in.” When her pet unfortunately developed cancer anyway, did this cast any doubt on the theories or practices she followed? No. Sadly, Ms. Paige was just filled with a vague guilt that she hadn’t kept her pet’s life “pure” enough and was somehow responsible for the cancer. So she rededicated herself to adding still more unproven and largely irrational preventative measures to her pet care routine. If her subsequent companions develop cancer, will she follow the same road even further? And if they don’t, will this constitute “proof” that the new additions worked?

This is an understandable but very dangerous pattern of thought that we are all in danger of succumbing to. We fear pain and illness and loss, naturally, so we try to prevent them and comfort ourselves with the idea that we are in control of our fate, that if we do the “right” things in terms of our physical and spiritual care of ourselves and our loved ones, we can prevent the suffering and pain we fear. But the universe gives little us little reason to believe that our magic rituals really work. The only thing in all the history of humankind, with all the myriad of lifestyle and spiritual practices we have employed, that has ever made a dramatic and unequivocal improvement in the length and quality of our lives has been the development of science, and the growth of true understanding and effective manipulation of the world science has allowed us. Many things are, maddeningly, beyond our control. But magical thinking, however sincere and well-intentioned, is not truly the best way to give our pets the best lives we can.

Other supporters of National Holistic Pets Day go even farther than Ms. Paige in misleading the public with comforting nonsense. This press release (ostensibly from the PetMD web site, though I can find no mention of the holiday on the PetMD site, and it would be a bit inconsistent for this company to promote the myth of holistic medicine since it runs a pet food and pet pharmacy business selling all the “toxins” the holistic crowd) contains the usual clichés from some of the usual sources.

homeopathy can treat the deepest constitutional causes of dog diseases and cat diseases…”While the ‘find it and kill it’ Western medical approach may work for infectious diseases, holistic medicine takes preventative measures by treating the whole body,” says Dr. Nancy Scanlan, executive director of the American Holistic Veterinary Medicine Association (AHVMA). “Holistic veterinary care can be much more effective when treating chronic illnesses like heart disease.”

While I respect Ms. Paige’s motives and efforts to improve the lives of pets in many different ways, it is unfortunate that her misconceptions about medicine have led her to throw those efforts behind the kind of nonsense that only drains energy, talent, and resources away from finding and employing truly effective healthcare for our pets. Many of the pets in the U.S. have too little access to preventative healthcare, or even treatment for illness, due to both economic factors and misconceptions about the need for regular care and the reliability of information found on the Internet. A campaign to raise awareness about the need for veterinary care should focus on those measures that are proven to benefit our pets, and despite Dr. Scanlon’s assurances, this is not the case for so-called holistic medicine. Perhaps we need a National Science-Based Pet Medicine Awareness Day?

Posted in General | 9 Comments

Standard Process=Standard Nonsense

Posted on August 29, 2011 by skeptvet

Standard Process is a company that has been selling dietary supplements since 1929. It was founded by a dentist, Royal Lee, who developed a number of unconventional theories about the role of nutrition in health and disease. In essence, Dr. Lee and his successors take rational, scientific principles and extend them well beyond reason and evidence to promote claims that the particular plant and animal extracts they provide have near magical medicinal qualities. This is the very paragon of pseudoscience, the presentation of unsupported, often irrational hypotheses, mingled with scientific terminology and a sprinkling of tangentially related actual scientific facts to create a set of faith beliefs that appear to be scientific but do not actually conform to the philosophy, methods, or data of legitimate science.

It is quite reasonable and demonstrably true, for example, that nutritional deficiencies can cause disease, and that supplementation with the appropriate nutrients can prevent and treat such diseases. This does not, however, support the generalization that all disease is associated with nutritional deficiencies, or that all disease can be ameliorated with proper nutritional supplementation. Food and nutrients of appropriate kind and quantity are unquestionably necessary for health and even life, but that has very little to do with whether or not the specific theories about the benefits of particular foods and nutrients sold by Standard Process are true.

Of course, Standard Process products are not simple vitamin and mineral supplements. They contain complex mélanges of plant and animal ingredients. The marketing materials talk a lot about the value of “whole foods.” The claim is frequently made that plant and animal tissues contain combinations of chemicals (never called by that dirty word, of course) that provide greater health prevention and treatment benefits in combination that individual nutrients can alone. And it is taken as a given that “processing” of any kind, including cooking, ruins the nutritional and health value of foods. The key to healthful supplements are that they contain whole, unprocessed, natural ingredients, preferably organically produced.

All of these are fairly standard arguments seen in the marketing materials for alternative approaches to nutrition. The evidence does not generally support such claims. Organic food appears to be no healthier than conventionally produced foods, though there may still be some environmental advantages to organic production methods. And while cooking and other kinds of processing do alter the nutrient content of foods, this is a pretty well-understood phenomenon. Some nutrients become more available, and those that are diminished by cooking can be effectively replaced. So the evidence does not support claimed health benefits for raw foods in humans or pets. “Natural,” of course is a meaningless marketing term. Synergy can exist between compounds in a whole plant, but it requires complex, thorough investigation to document that it actually does occur in any particular plant. And finally, the issue of “processing” of foods is a complex mishmash of fact and mythology. In general, “processed food” is used as a synonym for “junk food,” but clearly every time you wash, chop, season, or cook your food, you are “processing” it, and usually improving it. Claims about the nutritional inadequacy or deleterious effects of commercial pet foods are not supported by real evidence.

What is particularly odd about the emphasis in Standard Processes’ marketing materials on natural, unprocessed, whole foods is that their supplements cannot in any reasonable way be described by any of these buzzwords. They are complex mixtures of herbs, plant extracts, vitamins and minerals combined with “Protomorphogen” and “Cytosol” extracts. highly processed substances derived through proprietary processes from animal tissues, These mixtures are then compounded into tablets or powders. So mixtures that would never be found in nature in forms that are the result of extensive technological processing are sold as natural whole foods?

The animal tissue extracts represent another element to Dr. Lee’s unproven, pseudoscientific nutritional theories. It is true that deficiencies in the function of some glands can be remedied by supplementation with relevant substances from the same gland. However, it is usually true that purified isolates or synthetic forms of these glandular products are superior to whole organ supplements, and often the supplement cannot be given orally anyway. And none of this has any relevance to the broader claims that whole gland products or gland extracts prevent or treat disease through the action of numerous, often unidentified substances.

Ultimately, the idea that treating kidney disease by feeding ground up kidneys to the patient, as an example, is not a scientific hypothesis but yet another form of sympathetic magic. This is a descriptive term from anthropology which refers to a form of magical belief found in most cultures, that things which resemble one another in some superficial way can be used to influence each other. Mandrake root must be an aphrodisiac or fertility treatment because the root resembles a human penis; voodoo dolls that look like a particular person can be used to harm them; and diseases that involve a particular organ can be treated by feeding supplements made from that or a related organ.

There does not seem to be any real research evidence to support the claim than glandulars in general, or the “special” gland extracts sold by Standard Process, have any significant health benefits. Those who promote the use of these products support their assertions with clinical experience, case reports and uncontrolled case series, and reference to pre-clinical research showing that some chemicals from some glands have some effects. Much of the supporting research comes from publications devoted exclusively to promoting these products or alternative therapies in general. And, of course, there are plenty of anecdotes and testimonials to miraculous cures brought about by these products, which have their usual lack of probative value. Well-designed and conducted clinical trials published in mainstream peer-reviewed journals do not appear to exist, despite the fact that the company has been producing and marketing supplements for over 70 years.

As is usual with pseudoscience, claims about the products and unsupported theories are mingled with tangentially related facts from legitimate scientific theory and research. One example of the marketing materials for the Standard Process veterinary product line illustrates this technique. The document, published in Standard Process’ own pseudojournal Whole Food Nutrition Journal, begins with a list of known nutrient deficiency diseases. It then proceeds to point out that the transition from “traditional” to “modern” diets is associated with health problems. This has, of course, some truth to it, though it has nothing to do with the claims that will later come about the specific relationship between Standard Process supplements and health, and it ignores the fact that so-called “traditional” diets are themselves associated with nutritional deficiency diseases.

The infamous Pottenger study is mentioned, which is a common warning sign of veterinary nutritional pseudoscience. This is a poorly designed experiment from the 1940s that involved feeding milk and meat, either cooked or raw, to cats. The cats fed the cooked meat developed nutritional and developmental diseases, which is often cited as evidence that raw foods are healthier than cooked foods. Unfortunately, the complete lack of experimental controls or proper evaluation of the subject, and the simple fact that both diets were grossly deficient and utterly unlike the commercial pet foods the study is usually used to criticize, make the results meaningless. Pseudoscience at its best, or worst.

The pattern continues throughout the document, and is characteristic of the rest of Standard Process advertising. A mixture of hypotheses and outright fantasy with vaguely related scientific information to create the false impression that the whole is sound. What the company is pretty careful not to do is make direct claims that its products prevent or treat actual diseases. Thanks to the ridiculously lax regulation of dietary supplements, it is possible to suggest, imply, and in a multiplicity of clever ways mislead the consumer, and even veterinarians, into believing the products have proven value in disease treatment or prevention. However, straight out claims that the products are medicinal are not allowed. The company and its founder have been sanctioned numerous times in the past by the Food and Drug Administration for illegal claims about their products. The current leadership is now more careful. However, believers in these supplements, primarily chiropractors and naturopaths as well as “holistic” veterinarians, devise and teach each other strategies for deciding which supplements to use when.

Bottom Line
The theories about the relationship between food, nutrients and health invented by Dr. Lee and still promoted by Standard Process are unscientific and not supported by scientific evidence.

The marketing claims that the products are beneficial because they are unprocessed, natural, whole foods are both meaningless and inconsistent with the real nature of the products, which are highly processed, artificial mixtures of compounds.

The promotional materials used to advertise these products to veterinarians and consumers are highly misleading pseudoscience, mixing unproven and unscientific ideas with bits of real science that do not actual have anything to do with the validity of the claims made about the company’s theories or products.

There is no evidence beyond individual opinion, anecdotes, and poorly designed case series to indicate that Standard Process products have any value in treating or preventing disease. More than 70 years after the company began manufacturing and selling supplements, there are still no good quality clinical trials demonstrating that any of their products are effective for the prevention or treatment of any medical condition.

Ultimately, the choice to use these products is a gamble, trusting that notoriously unreliable forms of evidence such as anecdotes can accurately guide us in the absence of any real scientific evidence.

Posted in Herbs and Supplements | 142 Comments

Carl Sagan: Words of Wisdom

Posted on August 24, 2011 by skeptvet

The cure for a fallacious argument is a better argument, not the suppression of ideas.

Posted in General | 1 Comment

What Does “Scientifically Proven” Really Mean?

Posted on August 23, 2011 by skeptvet

Science as a Brand
I think of science as primarily an approach to knowledge; both a philosophy and collection of methods for developing an understanding of reality. Of course science is imperfect, both in itself and in how it is practiced by imperfect human beings. But the evidence of history is overwhelming and not rationally deniable that a scientific approach to health and disease works better than any other approach tried so far.

Largely because of the dramatic successes of scientific medicine, the label of “scientifically proven” has also become a potent marketing tool. There may be suspicion of scientists and technology, and plenty of interest in vague and comforting alternative philosophies, but when the chips are down people throughout the world trust science and scientific medicine more as the most reliable source of information and healthcare.

This is why even those dedicated to ideologies clearly incompatible with science, such as homeopaths, attempt to label their practices as scientifically validated.

Because of this, it is nearly impossible to find advertising for a healthcare product or service that does not claim the product is “scientifically proven” to work. Unfortunately, most of those who use this language to market their wares do not appear to know, or to care, what it actually means, and the information to judge the truth of the claim is rarely made available to consumers.

Can We Ever Really Prove Anything?
It is often said that nothing is ever absolutely proven in science. This is true to some extent in that, contrary to anti-science propaganda, science as a method is quite open-minded and aware of the limitations of human reason, and so the method allows for the possibility that any idea, no matter how established and venerated, can be proven false with adequate evidence. However, realistically there are some propositions that achieve a level of supporting evidence that makes any serious doubt about their truth perverse and irrational. I have no fear of being wrong when I say the Earth is not flat nor poised on the back of a turtle.

Similarly, it is often said that the absence of evidence is not evidence of absence, meaning that something as yet not thoroughly tested scientifically cannot be dismissed as false, only regarded as unproven. This is certainly true as well. Unfortunately, in the marketing of unconventional healthcare products this idea is often twisted into a claim that nothing can be regarded as false without an unachievable standard of voluminous and perfect quality evidence against it. But in the real world, we can’t have perfect evidence for everything, and we must apportion our limited resources rationally.

Homeopathy, for example, has a theory that cannot be true unless much of established science is wrong; the in vitro evidence of biologic effects or water memory is overwhelmingly negative; the lab animal and human clinical trials and the few veterinary clinical trials are overwhelmingly negative, with a strong correlation between the quality of the study and the failure to find a beneficial effect. It has been exhaustively evaluated for over a century without generating compelling scientific evidence that it works. Adding all this up, it is more than reasonable to dismiss it as a failed idea and move on without insisting that without more evidence we cannot “prove” homeopathy is a waste of time.

Sorry, Reality Really is Messy
So when deciding whether or not to trust a claim that something is scientifically proven, it is important to have some idea what such a claim might actually mean, if true, and what level of evidence is necessary to reasonably make it. To begin with, the level of evidence available in medicine rarely reaches the degree of certainty of that for the hypothesis that the Earth is round and not balanced on a turtle. Therefore, reliable science-based claims for medical services should usually be circumspect and should reflect the degree of supporting data. “Scientifically proven to treat cancer with no side effects!” is not a claim that is very likely to be supportable through real evidence. “May relieve the symptoms of cancer therapy in some patients with few side effects” is far more likely to be true.

An especially frustrating conundrum for proponents of science-based medicine is that it is far easier to sell something with strong, confident, absolute claims that are probably not true than with measured, realistic assessments supported by good evidence. Ambiguity and complexity are far less attractive than simple, confident narratives. And statistics and the details of scientific evidence are less compelling to potential customers than heartwarming testimonials with far less real evidentiary value. This gives faith-based medicine a significant public relations advantage over science-based medicine and skepticism. But the fact remains that truth is messy and full of uncertainty, and if someone is selling you something as extremely simple, clear-cut, and too good to be true, they probably are selling you a hope or a fantasy, not a real medical therapy.

The Hierarchy of Evidence
The core of evidence-based medicine is the idea that not all evidence is created equal. There are levels of evidence ranging from the suggestive but not very reliable to the solid and trustworthy, though never perfect. When reading a claim that something is “scientifically proven,” you should try to find out what kind of evidence supports the claim, and make your acceptance of the claim proportional to the quality and quantity of the evidence provided.

One key principle to bear in mind is that we are by nature inclined to generate and trust evidence that confirms our beliefs. Even the smartest and most honest scientists have deep, unconscious biases in favor of their own ideas, and these biases influence how they conduct their work and how they interpret data. And such biases extend even beyond the individual. For example, it is generally far easier to publish, and publicize, studies that show a positive result than those that show a promising treatment doesn’t work. In some countries, such publication bias is so severe that negative studies are effectively never reported.

Therefore, a key principle in evaluating medical claims is Negative Evidence is More Reliable than Positive Evidence!!!! Sure, if you have ten studies by different researchers in different parts of the world, including some that deliberately set out to disprove the findings of earlier researchers, and they all get the same answer, you can be pretty sure that is the right answer. But when the evidence is conflicting, when early studies look better than later ones, when low quality studies are positive and better ones negative, or when only one research group can get positive results, the better bet by far is that the treatment being studied doesn’t work.

The following is a simplified list of kinds of evidence commonly encountered and how they ought to be interpreted. In general, the list goes from least reliable to most reliable.

1. Mere opinion– Bias and cognitive blind spots are part of being human, and they affect everybody no matter how smart or well-educated. Linus Pauling, for example, was a brilliant scientist, and arguably a really good person who won a Nobel Prize for chemistry and a Nobel Peace Prize. He was also spectacularly and obstinately wrong about the health benefits of megadoses of Vitamin C. While those who make no effort to acknowledge or control their own biases and rely entirely on faith are especially vulnerable to errors in judgment, absolutely no one is immune. So if the only evidence for a medical claim is that someone smart, kind, famous, or otherwise admirable believes it, the claim should be viewed very skeptically since this kind of evidence is deeply and persistently unreliable.

2. Testimonials– Testimonials are just stories people tell about their experiences and how they interpret them. They are not controlled in any way for bias or error, and they are highly unreliable. Testimonials are also subject to a kind of publication bias in that no one marketing a medical product or service is going to seek out, collect, and report every person’s experience. Positive stories are promoted as evidence the product works, and negative stories are ignored, suppressed, or explained away. Though the most common and emotionally compelling kind of evidence offered to sell medical products, testimonials are not scientific or trustworthy and deserve to be ignored.

3. Reasoning from First Principles– Sometimes marketers will tout something as scientifically proven and then describe some features of basic chemistry, physics, physiology, and so on to suggest how their product might work and why you should believe it does. Certainly, a theory based on established scientific principles is a lot more likely to be true than one which is not compatible with well-established knowledge. However, living organisms are complex and extrapolating from basic science to actual patients is risky and unreliable. Just because something makes sense or ought to work based on a plausible theory does not mean it actually does. This is one of those bits of evidence that is necessary but not sufficient to demonstrate a therapy is useful.

4. Test Tubes and Guinea Pigs – Basic preclinical research into a promising medical treatment begins with testing the underlying theory behind an idea. If a proposed cure for cancer doesn’t kill cancer cells in a test tube, it’s probably not worth giving to patients. But again just because something works in the simplified, controlled environment of the lab doesn’t mean it will be safe or effective in living animals. Bleach kills cancer in the test tube, but that doesn’t mean we should drink it or inject it into people or pets with cancer! Similarly, all mammals have a lot in common, so if it kills rats it could be dangerous for dogs or people, and if it cures cancer in mice, it might be useful for cancer in cats and cows. But, there are also important differences between species, and it is never appropriate to simply assume the results seen in one species will also be seen in another. This again is a type of evidence necessary to demonstrate a treatment could work, but not sufficient to claim it does.

5. Clinical Trials– This is a huge category of ways of investigating a medical treatment with many levels of reliability. Rather than describe all the different kinds of studies and their pros and cons, I will list some general factors that are useful in deciding whether the existence of a positive clinical trial justifies calling a product “scientifically proven.”

A. Strength in Numbers- Small trials are less reliable than large trials. A few trials are less reliable than many trials. Trials conducted by a couple of investigators or all in the same place are less trustworthy than trials conducted in multiple locations by many different investigators. Individual case studies or small case series are less reliable than larger group studies. In general, the credence given to clinical studies should be proportional to the size and number of the studies.

B. Controls for Bias- The more layers of control in place to minimize potential bias, the more likely the result is believable. Such controls include:

Treatment, Placebo, and No Treatment Groups
Random assignment of subject to these groups
Blinding so that as few people as possible, especially patients and those evaluating them, know who is in which group

C. Replication and Persistence- Since we all tend to see what we expect to see, even with the most honest intentions, individual studies are almost never the last word on a medical subject, especially positive studies that find what the investigators want and expect to find. A key feature to demonstrating something really works is repeated testing by different investigators in different populations. It is especially convincing when someone sets out to disprove the results of a previous study and ends up getting the same results as the original, because this requires data robust enough to contradict the biases of the researchers involved.

The Decline Effect is a phenomenon in which early studies of a new intervention look very impressive, and as further studies are done the results get less and less positive until the original effect essentially goes away. This most likely represents the scientific process gradually correcting an initial erroneous finding through attempts to replicate it. Because of this effect, single studies are rarely to be trusted as the final word on a scientific hypothesis. A true idea, a really effective therapy will withstand repeated testing and will continue to accumulate positive evidence, while a promising idea that isn’t actually true will fail to hold up to prolonged, repeated scrutiny. This is part of why systematic reviews, which are methodologically formalized surveys of the totality of the evidence provided by individual studies, are a more reliable indicator of the truth behind a claim than any of the individual studies themselves.

The Bottom Line
Because most people understand that science works better than any other method for determining which medical claims are true and which are false, promoting a therapy as “scientifically proven” is a powerful marketing tool. However, the level of evidence usually available in medicine rarely justifies sweeping, absolute claims. Less dramatic, more qualified and realistic claims are more likely to be true. And not all evidence is created equal. Some of the most common and emotionally compelling kinds of evidence used in medical advertising, such as the opinions of smart, famous people and the testimonials of satisfied customers, are actually the least reliable and most misleading kinds of evidence.

Even truly scientific evidence varies from merely suggestive to pretty clear and definitive. A plausible theory and preclinical research in test tubes and animal models are necessary to show a medical treatment could work, but they are not sufficient to prove it really does work. And even evidence from published clinical trials must be given credence in proportion to the size, number, and quality of the studies that support a claim. Finally, since our biases are almost always in favor of confirming what we already believe to be true, negative evidence is far more reliable than positive evidence.

Posted in General, Science-Based Veterinary Medicine | 4 Comments

Web of Trust and the WOT Project

Posted on August 19, 2011 by skeptvet

Web of Trust (WOT) is a crowdsourced ratings system that rates the safety and reliability of web sites. These ratings are generated by users who visit the sites. They can be based on security concerns, but they are mostly based on ratings from individuals who either like or dislike the content. WOT has been integrated into Facebook so that when Facebook users click on a link to a site with a poor WOT reputation, they are warned the site may be unreliable. This has a great potential to influence the traffic to a web site.

WOT can be both useful and problematic for skeptics. It is useful for us to be able to rate and comment on sites that offer unreliable, unscientific information on alternative medicine, for example. However, it also provides an opportunity for those who don’t like our message to rate our sites negatively, which can discourage those seeking information from coming to them.

Tim Farley, of the site What’s the Harm? and Erik Davis of Skeptic North have discussed the potential positive and negative effects of WOT on the ability of skeptics to educate the public, and Erik has created the WOT Project, an effort to identify reliable skeptical web sites and encourage skeptics to rate them positively so that their information will be more readily available.

This project is currently of particular interest to me since after reading about it I discovered that the SkeptVet and SkeptVet Blog have poor WOT reputations. Partly this stems from a hacking issue which I only became aware of several months ago when my host notified me that my site had been cleaned of some malware and that I had to reset all of my passwords. The blacklisting site that originally flagged my domain has since removed it’s warning.

But I also have had a small number of ratings by individuals (18) which are all negative. I suspect this is the work of CAM proponents angered by the content of my posts. So as well as encouraging everyone to participate in the WOT Project in general, I would like to ask readers who believe the content here is useful to got to the SkeptVet WOT profile and provide a positive rating and comment. Hopefully, this will help prevent those who see the site when searching for information about alternative veterinary medicine from being warned away from it by WOT.

Thanks!

Posted in General | 13 Comments

Another Homeopathy Lawsuit-This time one that at least makes sense!

Posted on August 17, 2011 by skeptvet

There has certainly been a lot of talk lately about homeopathy and lawsuits. I have discussed the Academy of Veterinary Homeopathy’s attempt to obtain through litigation the legitimacy they can’t achieve by proving their methods work through scientific research. And Science-Based Medicine had an article today about the French company Boiron suing an Italian blogger for pointing out that their product Oscillo is nothing but a sugar pill and cannot possibly be useful for treating flu symptoms. So I admit I was a little bit ambivalent to see the tables turned by a lawsuit in California, accusing Boiron of fraud for implying Oscillo has therapeutic effects. In general, I don’t believe the courts are the best place to adjudicate disputes about the scientific merits of medical therapies. However, it is true that homeopathy cannot be viewed as anything other than delusion or fraud, and it is satisfying to see someone has the courage to point out that there can be no reasonable justification for profiting from selling homeopathic products.

The complaint is succinct and illustrates starkly how ridiculous it is to market any homeopathic remedy as if it were medicine.

Oscillococcinum (the “Ocillo”) is nothing more than a sugar pill that Defendants falsely advertise has the ability to cure the flu. In reality, Oscillo has no impact on the flu or any symptoms that accompany the flu…

The truth is that the listed active ingredient in Oscillo, Anas Barbariae Hepatis et Cordis Extractum, is neither active in combating the flu nor is it actually an ingredient in Oscillo… Anas Barbariae Hepatis et Cordis Extractum has no known medicinal quality, further, in the extreme dilution claimed by Defendants, it has no impact on the human body whatsoever because it is not present in Oscillo.

Defendants claim that the active ingredient in Oscillo, Anas Barbariae Hepatis et Cordis Extractum, is diluted to 200CK…At this purported dilution, the probability of getting 1 molecule of the active ingredient of Oscillo in a regular dosage is approximately equal to winning the Powerball every week for an[sic] nearly an entire year…

Defendants are fully aware that there is no Anas Barbariae Hepatis et Cordis Extractum present in Oscillo. In an interview with the U.S. News and World Report, Defendants stated, “[of] course its safe. There’s nothing in it.”

…Defendants sell Oscillo for approximately $10 per unit based on the preceding false advertising claims. As a result, Defendants have wrongfully taken milloons of dollars from California consumers.

I am not optimistic that the suit will be successful or meaningfully impact the marketing of water as medicine. But as a matter of principle, and as an opportunity to educate the public, the lawsuit is worthwhile, and I applaud the plaintiff for making his efforts.

Posted in Homeopathy, Law, Regulation, and Politics | 4 Comments

Academy of Veterinary Homeopathy Lawsuit Update

Posted on August 16, 2011 by skeptvet

Back in May, I wrote about a lawsuit involving the Academy of Veterinary Homeopathy (AVH) and the American Association of Veterinary State Boards (AAVSB) committee that certifies continuing education courses veterinarians must take to maintain their state licensure (the RACE committee). In brief, the RACE committee changed their standards for approving continuing education programs to require some minimal standards of scientific legitimacy for veterinary continuing education. The standards requires approved courses,

build upon or refresh the participant in the standards for practice and the foundational, evidence-based material presented in accredited colleges or schools of veterinary medicine or accredited veterinary technician programs…CE programs that advocate unscientific modalities of diagnosis or therapy are not eligible for RACE approval…All scientific information referred to, reported or used in RACE Program Applications in support or justification of an animal-care recommendation must conform to the medically accepted and scientifically supported standards of experimental design, data collection and analysis.

As I’ve discussed in detail before, homeopathy cannot by any but the most absurd contortions of reason be viewed as a scientifically legitimate or validated approach to health care, so it is not surprising that once RACE ceased rubber stamping applications for approval and applied these reasonable standards, homeopathy courses were judged ineligible for continuing education credit. It is also not surprising, of course, that homeopaths and others practicing scientifically questionable veterinary medical methods would object.

What is surprising and disturbing, however, is that the limited media coverage of the AVH lawsuit has been generally biased in favor of the AVH position, and there has been virtually no criticism of the deeply anti-science stance of the AVH, which if successful will essentially end all meaningful regulation of veterinary continuing education. Like much media coverage of creationism, journalists seem to believe that fair coverage requires ignoring the overwhelming consensus among scientists and veterinarians that homeopathy is nonsense and presenting veterinary homeopaths as a legitimate minority community being unjustly discriminated against. The media reports I have seen so far seem to entirely ignore the underlying issue of the scientific evidence against homeopathy or the threat the lawsuit, if successful, poses to the very idea of regulating the standard of veterinary care through the process of state licensure.

The Media Gets It Wrong
The Veterinary Practice News reported on this lawsuit in early August. In a roughly 2000 word article, the author extensively quoted five supporters of homeopathy and of the lawsuit. She also quoted an official at the AAVSB who was not free to comment on pending litigation. And finally, she interviewed me for the article as the sole critic of the AVH position.

I was quoted as saying that homeopathy was not a science-based intervention, which is accurate. I was also quoted as saying that, “Alternative medicine providers are often better at treating psychological aspects of a medical incident an owner is dealing with, and there’s no doubt they are caring and compassionate…”This is partially correct in that I did acknowledge that alternative practitioners are undoubtedly as caring and compassionate as other veterinarians, but it misrepresents the point I was making that the reason methods like homeopathy are popular with a small percentage of the pet-owning public is not because they actually work but because of the psychological effects, essentially a placebo-by-proxy, that the interaction with the practitioner has on the owner.

Lastly, I was quoted as saying that, “these therapies are not taught in veterinary schools.” This is followed by a “gotcha” list of veterinary schools that offer elective courses in “integrative medicine” or have “holistic medicine” student organizations. This is clearly intended to undermine the credibility of my comments. However, this is again a manipulative misrepresentation of my position.

Homeopathy is clearly not part of the core veterinary curriculum, nor is it generally accepted as a valid approach to medicine at U.S. veterinary colleges. The AVH does not dispute this in their complaint. And of the four veterinary schools (out of 28 in the U.S.) mentioned in the article as having “elective courses in CAVM or integrative veterinary medicine,” I could not find any that actually do have a course in homeopathy, though CSU does offer an elective called “Critical Overview of Complementary and Alternative Medicine” taught by Narda Robinson, who is a vocal critic of homeopathy. It is possible, of course, that a couple of schools do have credulous individuals on faculty who teach that homeopathy is scientifically legitimate, but if so these represent a rare minority opinion which is discounted by the overwhelming majority of veterinary scientists. The article was a barely disguised propaganda piece for the AVH position with only a superficial nod towards the idea of journalistic neutrality.

Another article on the subject was released today by the Veterinary Information Network (VIN) News Service. This article is more neutral than the VPN piece, but it still creates a false impression of the nature of the debate. It misrepresents the conflict as a balanced difference of opinion within the profession, when in fact it is about a small group of believers in a long-discredited belief system agitating for a special exemption from the scientific standards normally applied to mainstream veterinary medical practices.

The article extensively quotes the AVH veterinarian and attorney who filed the lawsuit, and also less extensively the president of the AAVSB. In general, much attention is given to the idea that homeopathy and other alternative approaches are “discriminated against,” and almost no attention is given the underlying scientific issue and the question of whether education of licensed veterinarians should be rooted in accepted science.

What’s the Point of Continuing Education for Vets?
I have discussed the legal and historical issues of licensing healthcare providers, including veterinarians, in detail elsewhere. In brief, the state is required to establish standards for the practice of medicine and issue licenses to healthcare providers in order to protect the public health and prevent unsafe and ineffective treatments from being sold as legitimate healthcare. Prior to the development of this practice, quacks and charlatans routinely sold useless or harmful, even deadly “remedies” freely, to the great harm of patients in need of real care. Continuing education requirements are part of this system, and they are intended to ensure that veterinarians stay current on progress in veterinary medicine.

It makes no sense to have such standards if there is no reasonable, scientific criteria for what counts as legitimate continuing education. Should veterinarians be able to maintain their licensure by studying anything they want? Psychic surgery, astrology, voodoo, faith healing, etc? The AVH argues that the standard of scientific evidence is fundamentally unfair. According to the VIN article, the new RACE standards’ emphasis on science, “worked to preclude homeopathic courses that were not based on what RACE committee members considered to be clear, evidence-based science. It narrowed the road to acceptance, critics say, giving more weight to published science and less to the experts in homeopathy. ”

This as much as admits that homeopathy is not accepted as scientifically legitimate by anyone but homeopaths. The logical consequence of this, apparently, is that only experts in homeopathy should be allowed to judge if homeopathy is scientifically legitimate. And presumably only psychics, astrologers, and voodoo priests should be allowed to judge whether these are legitimate veterinary medical approaches?

This is a form of special pleading which says that there is no real scientific standard of evidence that can prove anything is or is not effective medicine, so followers of every individual approach should simply be free to judge their own practices by their own standards and then the state should simply endorse their judgments. Such an approach effectively eliminates any meaningful standard of quality for veterinary care and takes us back to the medical anarchism of the 19th century.

Taking this sort of approach even further, the American Holistic Veterinary Medicine Association has formed its own standards group, the Registry of Alternative and Integrative Veterinary Medical Education (RAIVE) to circumvent the RACE standards board with one stacked with believers in alternative therapies and more inclined to rubber stamp continuing education in these approaches. This will be meaningless, of course, unless state veterinary boards agree to accept RAIVE in lieu of RACE approval. Of course, since such boards are fundamentally political, rather than scientific, agencies, and they have a solid history of ignoring blatantly even the most egregiously ridiculous and harmful sorts of medical nonsense so long as it is promulgated by a licensed veterinarian, it seems not unlikely that this separate-and-equal approach to deciding what is legitimate medicine will succeed.

Why Does It Matter?
The simple answer to this is that our patients are better off if they receive effective care. And this is more likely to happen if veterinarians are trained in legitimate scientific medicine. We have a special privilege by virtue of the license we are granted by the state to practice veterinary medicine. We can make our living providing healthcare for animals. And this privilege is granted us with the understanding that we will employ safe, effective, scientifically valid treatments. Our clients come to us trusting that our status as licensed veterinarians means we are meaningfully different from unlicensed individuals who might offer veterinary services. The state has essentially certified that we can be trusted to take proper care of our clients’ companion animals using valid methods.

If any and all methods are considered equally acceptable as support for our licensure, and if only believers in a given method are allowed to judge the legitimacy of that method, regardless of how few they are or how lacking the scientific evidence in support of their beliefs, than licensure is meaningless. A pet owner has no way of knowing if the licensed veterinarian they go to is practicing accepted, scientific medicine or a completely bogus method they have invented and judged legitimate all by themselves.

The harm that unscientific approaches to medicine, including homeopathy, can do is real and easy to illustrate (here and here, for example). The issue behind the AVH lawsuit is not fairness or open-mindedness, it is about whether scientific evidence and regulatory standards are to have any meaning or any influence on the quality of veterinary care the public is offered. The AVH is fundamentally seeking an exemption from any such standards and the right of any group to judge their own beliefs and promote them as legitimate under the imprimatur of state government without interference from the judgment of the rest of the profession or state regulators.

Posted in Homeopathy, Law, Regulation, and Politics | 11 Comments

Probiotic Fortiflora: Not apparently very helpful in preventing diarrhea in shelter animals

Posted on August 9, 2011 by skeptvet

Probiotics, living microorganisms fed to humans and animals to prevent or treat disease, are an interesting area of ongoing research. I have written about this intervention a number of times (1,2) and it seems a promising area of research, though the current evidence for meaningful beneficial effects is quite limited. There is reasonable evidence for some benefit in treating antibiotic-associated diarrhea or acute diarrhea of unknown cause(3). The evidence is not very good for many other claimed benefits, such as strengthening of immune system function, treatment of kidney disease(4,5), management of feline upper respiratory viral infections(6), and so on. And there are serious problems with irresponsible, excessive hype(7) and poor quality control(8) for probiotics.

Overall, I am cautiously optimistic that we will eventually find legitimate therapeutic uses for some probiotics, though I find the existing evidence unconvincing for most claims currently made about them. A new study looking at the use of Fortiflora, a veterinary probiotic product, for control of diarrhea in shelter animals, does not add much support to the proposed value of this probiotic.

Bybee SN, Scorza AV, Lappin MR. Effect of the Probiotic Enterococcus faecium SF68 on Presence of Diarrhea in Cats and Dogs Housed in an Animal Shelter. J Vet Intern Med. 2011 Jul;25(4):856-60.

Cats in this study were housed for variable periods of time in two rooms, one for previously owned cats and another for feral cats. Canine subjects were also housed in two separate areas. Subjects in both rooms for each species were observed for 4 weeks to establish a baseline incidence of diarrhea in the population. Then subjects in one of the rooms for each species were given Fortiflora daily for 4 weeks while the subjects in the other room were given a placebo. All subjects were taken off the Fortiflora and placebo for one week, and then the treatments were switched, so subjects in the room that had originally received placebo got the Fortiflora and vice versa.

The stool of every animal was scored on a stool consistency chart every day. Abnormal stool samples were evaluated for parasites whenever possible, and an effort was made to evaluate a normal stool from another animal in the same room at the same time to identify what if any role parasites played in the incidence of diarrhea. It is not clear from the paper what if any treatment was given for diarrhea or fecal parasites.

For both dogs and cats, some fecal parasites were detected in some individuals, but the rate of parasitism was no higher in those with diarrhea than in those with normal stools, so the parasites did not seem to influence the incidence of diarrhea significantly in a way that would complicate evaluating the effect of the probiotic. This effect, however, was not especially clear. For the dogs, there was no significant different in the incidence of diarrhea between those getting the Fortiflora and those receiving the placebo regardless of how the data was analyzed. The overall incidence of diarrhea in both groups was lower than expected for reasons that were not identified.

In the cat groups, the overall incidence of diarrhea was no different between the probiotic and placebo groups. However, when the data was broken down to compare the proportion of cats having diarrhea for more than 2 days, this was lower in the probiotic group than in the control group, though the level of significance was not dramatic (P=0.0297 with a cutoff of <0.05).

The authors conclude this finding “suggests the probiotic may have beneficial effects on the gastrointestinal tract.” This is certainly possible, but this particular study provides little support for the idea.

Posted in Herbs and Supplements | 3 Comments

Denamarin: Does it prevent chemotherapy-induced liver damage?

Posted on August 8, 2011 by skeptvet

Silymarin and s-adensylmethionine (SAM-e) are plant-derived chemicals frequently used as supplements for a wide variety of applications. I’ve written about both before, evaluating the available evidence in humans and in dogs and cats (1,2,3). So far, the evidence concerning the safety and efficacy of these supplements is limited and conflicting. A recent study, however, provides a little bit more low-level support for the use of at least one combination product, known as Denamarin, containing these chemicals.

KA, Hammond GM, Irish AM, Kent MS, Guerrero TA, Rodriguez CO, Griffin DW. Prospective Randomized Clinical Trial Assessing the Efficacy of Denamarin for Prevention of CCNU-Induced Hepatopathy in Tumor-Bearing Dogs. J Vet Intern Med. 2011 Jul;25(4):838-45.

In this study, fifty dogs being treated for various cancers with the chemotherapy agent lomustine (CCNU) were randomly divided into two groups. One group was given Denamarin and the other was not. CCNU is known to frequently cause increases in liver enzymes measured in the blood. Although it is much more rarely the cause of serious liver damage, the elevations in liver enzyme levels often causes concern that can lead to delaying or discontinuing use of the drug. The goal of the study was to see if Denamrin could prevent the increase in liver enzyme levels.

In terms of this narrow criteria, the study showed a positive effect. While only 68% of the dogs on Denamarin showed liver enzyme increased, 86% of those not on the supplement had increased levels of the major enzyme of interest, alanine aminotransferase (ALT). And while these elevations reached the highest levels in 28% of the control dogs, only 7% of the dogs on Denamrin showed such very high increases in ALT.

There are a number of caveats, however, that limit the degree to which these results can support a general recommendation to use Denamarin in dogs given CCNU. The cause of liver enzyme elevations was not determined in most dogs, so it is possible that a progression of the underlying cancer, rather than the CCNU, caused the increases in some of these dogs. And only 1 of the fifty dogs actually showed clinical symptoms associated with liver damage, so it even if Denamarin prevents increased enzyme levels, this may or may not have any actual clinical benefits.

Methodologically, there are some additional caveats that must be considered in judging the significance of this study. There was no placebo group, and owners and investigators were not blinded to the treatment group. While this potential source of bias would not have directly affected ALT measurements, it could potentially have led to differences in how the dogs in the two groups were treated, which might have indirectly affected these levels. This is especially a concern since the study was funded by the manufacturer of Denamarin, and several of the authors have financial links to the company.

Overall, this study provides low-level evidence that Denamarin may have benefits in protecting against CCNU-induced liver damage in dogs with cancer. Independent replication with better controls and more comprehensive assessment of outcome would help to determine if the current results truly represent a clinically meaningful benefit from this supplement or not. However, given the low level of risk associated with this specific product, it is not unreasonable to consider using this supplement for this indication. This does not, of course, translate into support for a generalized use of Denamarin for any and all liver problems.

Posted in Herbs and Supplements | 16 Comments