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What Is Acupuncture?

The Science of Medicine

Steven Novella

Volume 35.4, July/August 2011

Scientific jargon can be impenetrable, but it’s often necessary—ideas must be precisely and unambiguously defined in order to be useful. It’s difficult to test a vague notion or subject an amorphous concept to examination. So we must first define what acupuncture actually is before we can ask whether acupuncture works. This is not as easy as it might seem.

Acupuncture is often referred to as an ancient Chinese practice, but in actuality it’s neither very ancient nor exclusively Chinese. The modern practice of acupuncture is only decades—not centuries or millennia, as is often claimed—old (Ramey 2010). It has antecedents in ancient times, but the practice of needling in Asia was not much different from the practice of bloodletting in the West (Novella 2010).

The National Center for Complementary and Alternative Medicine (NCCAM) has this to say about the definition of acupuncture:

The term “acupuncture” describes a family of procedures involving the stimulation of anatomical points on the body using a variety of techniques. The acupuncture technique that has been most often studied scientifically involves penetrating the skin with thin, solid, metallic needles that are manipulated by the hands or by electrical stimulation. (NCCAM 2011)

It appears the definition of acupuncture is not tied to any alleged mechanism of action. Some definitions mention Traditional Chinese Medicine (TCM) and either directly state or imply that acupuncture works by influencing the flow and balance of chi, or life energy. Such notions are little more than prescientific superstition, so modern proponents are often vague on mechanism or refer to highly speculative and unproven physiological mechanisms. Regardless of any potential mechanism, there are two features that seem to define acupuncture: the existence of specific acupuncture points at various locations on the body and the stimulation of these points by “a variety of techniques,” most commonly inserting thin needles through the skin.

So-called electroacupuncture is very problematic in terms of scientific specificity, because electrical stimulation through the skin has known physiological effects independent of the existence of acupuncture points. Scientific experiments are designed to control for as many variables as possible; only by isolating variables can we say which variable is having which effect. Electroacupuncture mixes variables, making it impossible to separate out the ones specific to acupuncture from the effects of electrical stimulation itself.

Needle insertion also has nonspecific physiological effects independent of any notion of acupuncture, but these are likely minimal, transient, and local. So for the purpose of experimentation, it is reasonable to define acupuncture as the insertion of thin needles into acupuncture points.

Clinical studies into the effectiveness of acupuncture have evolved over recent years, and there have actually been quite a few well-designed studies that adequately isolate these two variables (acupuncture points and needle insertion). For example, many studies compare verum acupuncture (true acupuncture in which needles are inserted into the alleged proper acupuncture points for the condition being treated) to sham acupuncture (in which needles are inserted into the “wrong” locations). These studies overwhelmingly show that needle location does not matter—verum acupuncture is no more effective than sham acupuncture (Moffet 2009; Ernst 2009).

Some trials also control for the variable of needle insertion, using placebo or simulated acupuncture in which opaque sheaths are used and a dull needle is pressed against the skin when the plunger is depressed, but there is no skin penetration. Alternatively, toothpicks have been used to simulate the sensation of acupuncture without going through the skin. Again, when this variable is isolated, it turns out that simulated acupuncture works as well as verum acupuncture. This is true of the largest and best trials of acupuncture for the most common uses, such as reducing back pain (Haake et al. 2007) and treating nausea (Enblom et al. 2011).

Therefore, if we define acupuncture as using needle insertion to stimulate acupuncture points, and the best scientific evidence shows that acupuncture points do not exist (it doesn’t matter where you stick the needles) and needle insertion has no effect (it doesn’t matter whether or not you stick the needles), then does acupuncture work? I think the only reasonable answer is no; there is no reality to acupuncture or the concepts upon which it is based.

If anything can be said to have a measurable effect in acupuncture trials it is the therapeutic ritual that surrounds acupuncture (but not the acupuncture itself). Even these effects are modest and nonspecific—they result from a subjective sense of well-being gained from the kind attention and relaxation that attends the acupuncture ritual.

We have known for decades that a good bedside manner, with some relaxation and encouragement, makes people feel better. This may create the illusion that whatever specific intervention accompanies these nonspecific effects is itself having some effect. That is the very point of scientific experiments: to isolate these variables. And when that is properly done, it becomes increasingly clear that acupuncture (the sticking of needles into alleged acupuncture points) does not work.

References

Enblom A., M. Lekander, M. Hammar, et al. 2011. Getting the grip on nonspecific treatment effects: Emesis in patients randomized to acupuncture or sham compared to patients receiving standard care. PLoS ONE 6(3): e14766. doi:10.1371/journal.pone.0014766.

Ernst, E. 2009. Acupuncture: What does the most reliable evidence tell us? Journal of Pain and Symptom Management. 37(4) (April): 709–14.

Haake, M., H.H. Müller, C. Schade-Brittinger, et al. 2007. German acupuncture trials (GERAC) for chronic low back pain: Randomized, multicenter, blinded, parallel-group trial with 3 groups. Archives of Internal Medicine. 167(17): 1892–98.

Moffet, H.H. 2009. Sham acupuncture may be as efficacious as true acupuncture: A systematic review of clinical trials. Journal of Alternative Complementary Medicine. 15(3) (March):213–16.

National Center for Complementary and Alternative Medicine (NCCAM). 2011. Acupuncture: An Introduction. Available online at http://nccam.nih.gov/health/acupuncture/introduction.htm.

Novella, S. 2010. Modern bloodletting (blog post). Neurologica (July 6). Available online at http://theness.com/neurologicablog/?p=2099.

Ramey, D. 2010. Acupuncture and history: The “ancient” therapy that’s been around for several decades (blog post). Science-Based Medicine (October 18). Available online at www.sciencebasedmedicine.org/?p=7660.

Steven Novella

Steven Novella, MD, is an assistant professor of neurology at Yale University School of Medicine. He is the host of the Skeptics’ Guide to the Universe podcast, author of the NeuroLogica blog, executive editor of the Science-Based Medicine blog, and president of The New England Skeptical Society.