A Salient, Reasonable Explanation for Acupuncture Efficacy

Accupuncture Ass by Zoomar

(photo: Zoomar)

    I've always been an acupuncture skeptic, but now I'm having second thoughts. Chris Kesser of The Healthy Skeptic has a great five-part series that attempts to explain the observed benefits of acupuncture in terms of established physiological principles. No meridians found here!

Highlights:

The “energy meridian” model that has become the
default explanation of Chinese medicine US is not only out of sync with
our modern, scientific understanding of the body – it’s also completely
inconsistent with classical Chinese medical theory.  In other words,
we’ve made up our own western version of Chinese medicine that has
little to do with how it was understood and practiced since it began
more than 3,000 years ago in China.  

This gross mischaracterization has kept Chinese medicine on the
fringes of conventional medical care since the 1930s and 1940s.  Most
doctors and patients have simply been unable to accept the explanation
they’ve been offered for how acupuncture works. The result is that
acupuncture has come to be seen as either a mystical, psychic medicine
or a foofy, relaxing spa-type treatment.

And that’s a big shame. Because Chinese medicine is in fact a
complete system of medicine that has successfully treated many common
health conditions for more than 2,500 years. Chinese medicine was
passed through the ages in an unbroken lineage of some of the best
minds of China. It was used by emperors and the royal courts to help
them live into their 90s and stay fertile into their 80s at a time when
the average life expectancy in the west was 30 years.

Inserting needles into the skin at peripheral sites “jumps” the
neural threshold on the position nerve pathway, so that the signal can
reach the brain. Once the signal reaches the brain, the whole series of
events I described in the paragraphs above kicks in. The brain
recognizes there is pain and where it’s coming from and releases
enkephalins (painkillers).

This initial response is very fast. It should be perceived as almost
instantaneous by the patient. But after the needling therapy the
patient goes home and the pain comes back. The old bad habit of the
nerve chronically firing below the threshold re-establishes itself. The
body, just like the mind, has a hard time breaking bad habits.

But if the patient returns in a couple of days to get another
treatment, the neural threshold will be jumped again. And if you keep
jumping the neural threshold, eventually the central and peripheral
nervous system figure out that it’s better to operate in the non-pain
state than in the pain state. The technical term for this is
re-establishment of neurological homeostasis.

Once this happens, the brain is no longer receiving pain signals
from the knee. It no longer thinks the knee is injured or threatening
the survival of the body. Now, instead of restricting blood flow to the
knee, the brain does the opposite. It immediately vasodilates the
capillaries and venules around the knee, which increases blood flow and
begins the healing process.

There are millions of immune cells called mast cells in the dermis
of the skin. These cells are like water balloons full of fatty
molecules called leukotrienes and prostaglandins A & B. When a
needle is inserted into the skin, it pops the mast cells and releases
the leukotrienes and prostaglandins. Prostaglandins cause the cutaneous
nerve in the area to fire (which activates the process described in the
previous paragraphs). Leukotrienes are the strongest anti-inflammatory
substance the body can produce.

Leukotrienes cause local capillaries to vasodilate and become
permeable. White blood cells called macrophages leak out through the
capillaries and immediately begin to heal the damage caused by the
needle stick.

However, the healing caused by the needle insertion isn’t limited to
the damage caused by the needle. If there is other damage in the area
from previous traumas or injuries, that will also be addressed by the
immune chemicals released by the needle insertion.

What’s more, the micro-trauma caused by the needle starts a systemic
immune response. This promotes healing of the soft tissue throughout
the body – not just at the needling site. After the needles are
removed, the needle-induced lesions continue to stimulate the body
until the lesions heal. This means that the anti-inflammatory effect of
acupuncture persists for 2-3 days (and sometimes as long as a week)
after the needle is withdrawn.

The entire series is really, really, really worth a read, as is the rest of the site.

    This article doesn't prove anything- the author doesn't cite any peer-referenced research for his claims, and the whole thing is written for the consumption of blog readers, no medical professionals. However, it turns acupuncture from something that can only be explained by placebo effects into a holistic treatment with a realistic mechanism for its effects. I'm looking forward to more research in this field, and if my insurance covers it, I just might go look for a needle-sticker the next time I run into chronic pain. Is acupuncture destined to become a new part of the Paleo-Pragmatist lifestyle?

Lingering questions:

  • Does it matter where needles get stuck? What sort of precision is required? Would there be a difference in reported pain between patients treated according to traditional guidelines on placement and those in whom the needles were stuck more or less at random? (Some research on this here)
  • How big of a role does placebo play? This could be tested by using two trained practitioners, one of whom offers more assurance and explanation about the practice than others. It would be even more interesting if you split the explainers into two groups: one who explained the energy meridian model, and another who explained the mechanism from this article.