Brennen McKenzie, VMD
Dr. Brennen McKenzie is the author of Placebos for Pets and the blog SkeptVet.com. He practices in the Bay Area of California.
Growing up in the '70s, I saw acupuncture, herbal medicine and other alternative therapies explode in popularity. Since I'm a California boy and come from somewhat of a hippie background, I was favorably inclined toward some of these therapies myself. But when I got to veterinary school, I found very little discussion of alternative medicine in the general curriculum.
So I started to look into the scientific literature on my own, and I was surprised at how little I found in the way of reliable evidence. I discovered that much of alternative medicine is based on the notion that something that's been done for a long time must automatically be true and effective and we don't need more than our own personal experiences to validate it.
When I started practicing, I began researching individual alternative therapies so I could answer client questions knowledgeably: What do we know about homeopathy? What do we know about turmeric? What do we know about [fill in the blank with whatever's fashionable at the moment]?
It turns out that it's not as simple as going to the literature, finding the studies and saying thumbs-up or thumbs-down. There are deep philosophical differences between groups around how we decide what works and what doesn't—what evidence is meaningful and what isn't. In fact, some alternative medicine advocates are concerned that applying science to these practices strips them of their essential character; ultimately they are supposed to be "alternative."
But after spending a great deal of time and energy researching many alternative therapies and the philosophies behind them, here's my only general conclusion: The best way to figure out what's effective and what's not is science. To the extent that alternative practices dodge scientific validation, they cannot be considered valid medicine. Likewise, as veterinarians, we serve our patients and clients best when we are committed to a scientific approach. My bookPlacebos for Pets? (published in 2019) encapsulates 10 years' worth of thought and study in this area, but here's an overview.
How we know what we know
As professionals who want to promote health and healing in our patients, how do we decide if something works? One approach is that of personal experience: "I tried this supplement and my knee felt better, so now I know it works and everybody should use it." On the other hand, we have the scientific approach, which says: "We know our observations and experiences are flawed and subject to error. Therefore, we need a systematic method for figuring out what works. ‘Just try it and see' doesn't cut it."
Unfortunately, anecdotes have the horrifying characteristic of being both unreliable and incredibly convincing. And this is at the core of what makes therapies that are ineffective or unproven popular anyway.
One surprising conclusion from my research into unconventional therapies is that there really isn't any such thing as "alternative medicine." By using this label, its proponents are trying to create a category that's exempt from the rigorous standards of science to which everything else must measure up. As Tim Minchin, an Australian musician and comedian, puts it, "Alternative medicine, by definition, has either not been proved to work or has been proved not to work. You know what they call alternative medicine that's been proved to work? Medicine."
"Unfortunately, anecdotes have the horrifying characteristic of being both unreliable and incredibly convincing. And this is at the core of what makes therapies that are ineffective or unproven popular anyway."
Alternative medicine is actually an ideological category. Even though many of its practices are mutually incompatible in theory (for example, the core principles of homeopathy state that it won't work if you add herbs, acupuncture or chiropractic to it), they're linked by the ideological or even political idea that history and tradition are reliable evidence, that individual experience is paramount, and we don't need some fancy scientific study to tell us what works and what doesn't.
At the same time, we've seen incredible, unprecedented improvements in health and longevity in humans and animals since we started doing things scientifically. We humans went from mostly dying before we could grow up or, if we were lucky, making it to our 40s to nowadays often living to get old and rickety because we figured out how to understand health and disease scientifically. Science works better than stories.
The myth of individualization
One of the common arguments alternative medicine proponents put forth is that their therapies can't be studied using the scientific method because they are inherently designed to be individualized to the patient, whereas science treats all patients the same way and then compares results. But the notion that we individualize therapies in alternative medicine and we don't in science-based medicine is one of the great myths.
The truth is that everybody individualizes therapy. The issue is, how do you take information about groups and use it to guide treatment? Science does this through controlled studies involving placebos, blinding, randomization and other strategies to account for the inherent errors our brains make when we reason. In evidence-based medicine, the role of the clinician is to interpret the applicability and usefulness of scientific evidence to a particular patient in their context.
Alternative practitioners also use information collected from groups of people to guide individual therapy. But the information they use is tradition, collected anecdotes and personal experience. An acupuncturist decides that SP6 is the right point to use in an animal with a particular heat, wind or chi deficiency because acupuncturists have treated animals over many years and this is what they've noticed. That's also taking information from groups and applying it to the individual, but relying on uncontrolled observations and haphazard information rather than scientifically controlled information.
The myth of Western bias
Here's something else that comes up a lot in these conversations: the term "Western medicine." We need to get away from this expression, which implies that science is somehow the cultural property of Europe and North America and therefore we have a cultural bias in favor of it.
There are a couple of problems with that assumption. First, much of alternative medicine is Western. Homeopathy was invented in Germany and chiropractic in the United States. So alternative medicine is no less Western than anything else, other than some specific traditions like Ayurveda and Chinese medicine.
Also, science works everywhere you go. There's no country in the world where scientific medicine isn't the most popular and effective form of therapy as long as people have access to it. In Taiwan, where Chinese medicine is part of the culture, only about 25% of the population uses a Chinese medicine treatment in any given year.1 The rest is conventional science-based medicine.
"Western medicine" is basically an advertising term used to insinuate that people who don't like alternative therapies are ethnocentric. So let's use a better description. "Conventional," "science-based" and "evidence-based" medicine are all more accurate designations.
The rise of "integrative"
Speaking of labels, recently it's become accepted to use the word "integrative" to reflect an openness to therapies historically considered alternative. The premise is that every therapy is a tool, you pick the right tool for the job and you don't pay attention to where it came from because that's irrelevant.
This sounds great—as long as you're using the same standard of evidence for all the tools in your toolbox. But if you're integrating homeopathy with antibiotics, and antibiotics are scientifically validated and homeopathy is not, then you're mixing things together that are not equivalent in terms of their legitimacy or value. And I don't think you're benefiting the patient with that approach.
One of my favorite quotes on the subject comes from Mark Crislip, an infectious disease specialist in human medicine. He said, "If you mix apple pie and cow pie, you don't make the cow pie better; you make the apple pie worse." There's no benefit to integrating therapies unless they're all equivalently validated according to the same standards.
Again, "integrative medicine" has largely been an advertising tool. When it was called "alternative" in the '70s, it was truly meant to be something you did instead of conventional medicine. But when people get really sick, they want a medicine that works, and they tend to go for science-based medicine.
So then we went to "complementary" medicine, which meant we would use these therapies in addition to conventional medicine. But that makes it feel like a second-class citizen, like it's not "real" medicine. So "integrative" has become a way of saying all these therapies are equal and the wise person mixes them together as necessary. But that glosses over real differences in the evidence.
Even though I have used acupuncture in my own practice, I wouldn't call what I do "integrative" because I'm not making claims about it that go beyond what scientific evidence supports. I take the same evidence-based approach to everything I do with patients. And if you can prove to me that something works scientifically, then it's not "alternative" or "integrative" in any meaningful sense; it's just medicine.
The spectrum of evidence: From none to some
Alternative therapies run the gamut from absolutely no proof to reasonably science-based. At one extreme, homeopathy almost certainly has nothing to recommend it, and I would never suggest that it be used in place of other therapies. It's useless; it's worthless; we have enough evidence to say that definitively.
In addition, the things we call "energy medicine"—reiki, therapeutic touch and so on—are essentially faith-based activities. They rely on some mystical force that cannot be studied or manipulated in any scientific way and must be believed in and sensed intuitively. When you do try to study this force, you can't detect it or make it work. It's fine with me if people believe in those things—I'm not here to take anybody's religion away—but I don't think that's a sound basis for practicing medicine. It's a way of saying, "Here's something special we can't do science on, so you have to just trust us." And I don't buy that.
But, as I mentioned above, I am certified in acupuncture. I took a course in veterinary medical acupuncture from Narda Robinson, DO, DVM, MS, FAAMA, at Colorado State University because she approaches it in as scientific a way as possible. We toss out all of the yin and yang, the chi and the mystical stuff, and we say, "Sticking needles in animals clearly does things you can measure physiologically, so are those things predictable and beneficial?"
I tell clients I'm still not convinced it's useful, but if acupuncture is done carefully by somebody who knows anatomy, it's relatively low-risk. And as long as it's not used as a substitute for something known to work better, I'm happy to provide that service. I'd much rather do it myself with honest disclosure than send clients to a Chinese medicine veterinarian who tells them to stop their nonsteroidal anti-inflammatory pain meds, go on a raw diet and forego vaccines—things I believe are actively harmful.
Herbal medicine is even more promising than acupuncture, because clearly the chemicals in plants do things in the body. Many of our medicines come from studying plant chemicals and then using them in a scientifically guided way. The problem is that many people who practice herbal medicine rely on traditional schemes like Chinese medicine or Ayurveda and are reluctant to go the full route of studying their therapies scientifically. I think some herbal therapies could turn out to have tremendous utility if we would let go of the mystical, traditional schemes behind them or the belief that they're effective simply because they've been used for a long time and instead study them scientifically.
The pitfalls in veterinary medicine
As veterinarians, we live in an information-poor world. We're used to not having as much evidence as we'd like, and we don't have the resources to develop the research we want. Unfortunately, this leaves us vulnerable to adopting therapies for which we don't yet have reasonable evidence. This is true for some conventional therapies, like stem-cell treatments and tramadol, as much as it is for alternative therapies.
We are given a monopoly to practice veterinary medicine. We get a license that says, "We can do this and get paid for it and none of you can, and if you do, you'll go to jail." Part of the deal we've struck with society is that we will practice in a science-based manner. It's in the AVMA code of ethics. But I think we've been too comfortable basing things on experience and anecdote, and it leads us to trust new or unlikely therapies without enough real evidence.
Tramadol was widely used as an analgesic until we realized it didn't work for dogs. How many patients didn't get pain control because we didn't wait for the evidence? The same is true for most alternative therapies, and the problem is even greater because so many proponents of these treatments actively resist rigorous scientific testing of their methods.
We need to put the work in and commit to a scientific approach. A few people make some effort to do that—Dr. Robinson in acupuncture and Susan Wynn, DVM, CVA, CVCH, AHG, DACVN, in herbal medicine—but lots of people are trying to gain the appearance of scientific legitimacy without doing the work. I think it is a mistake to allow that to continue. We need to find out if any of these therapies really work and are safe, and we need to give up on those treatments that can't properly prove their safety and efficacy.
The goal: A more reasonable conversation
Alternative medicine is inherently a controversial topic, and that's unfortunate. If we focused on the validity of ideas and the evidence for and against particular therapies, the conversation wouldn't need to be as personal and hostile as it often is. But we attach our egos and our identity to the kind of medicine we practice.
If you've spent 20 years doing something and your validation for why you do it is your 20 years of experience, then my saying, "The evidence says that doesn't work" is a personal assault on you, your experience and your competence—and that's unfortunate. The biggest complaint (and most of the hate mail) I get is from people who feel like I'm invalidating their experience.
My response is that I'm not invalidating your experience or your life; I'm invalidating the applicability of your personal experiences to the general population and to the general safety or efficacy of medical therapies. If you want anecdotal experience, we have thousands of years of history showing that anecdotal evidence doesn't work and science works better. More importantly, we have scientific evidence for this as well.
Chinese medicine has been around for a really long time, and for most of it we didn't live past our 30s or 40s. We never got rid of smallpox or accomplished anything like what we've done since the advent of scientific investigation. There's good reason to believe science works better. I think it's unfortunate that we get caught up in personal and emotional debates when we should focus on consistent, objective and scientific testing of proposed therapies, not on what we feel or believe.
- Chen F-P, Chen T-J, Kung Y-Y et al. Use frequency of traditional Chinese medicine in Taiwan. BMC Health Serv Res 2007;7:26.