Science reports that a new study on mice shows that acupuncture activates pain-suppressing receptors. This is no surprise to the millions of people around the world who use acupuncture, but it’s always interesting when science discovers how things actually work.
Researchers have developed two hypotheses for how acupuncture relieves pain. One holds that the needle stimulates pain-sensing nerves, which trigger the brain to release opiumlike compounds called endorphins that circulate in the body. The other holds that acupuncture works through a placebo effect, in which the patient’s thinking releases endorphins.
Neuroscientist Maiken Nedergaard of the University of Rochester Medical Center in New York state was skeptical about both hypotheses because acupuncture doesn’t hurt and often works only when needles are inserted near the sore site. Nedergaard instead suspected that when acupuncturists insert and rotate needles, they cause minor damage to the tissue, which releases a compound called adenosine that acts as a local pain reliever.
Along those lines, the study did find that injecting a compound that boosts the levels of adenosine increases relief from pain.
You can read more here about how they did the study. More research needs to be done to see whether this works in humans the same way, but Vitaly Napadow, a Harvard Medical School neuroscientist, calls it “a landmark study” that was “very meticulously done, with a very clear hypothesis that was attacked on many different levels.”