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The thought of having needles inserted into your body may sound stressful. But to those who regularly receive acupuncture treatments, it’s quite relaxing, though scientists haven’t really been sure why. Now researchers from Georgetown University have found that needles placed at just the right parts of the body interrupt the transmission of stress hormones—the most robust evidence yet to indicate that acupuncture’s positive effects go beyond just placebo.
“The benefits of acupuncture are well known by those who use it, but such proof is anecdotal. This research, the culmination of a number of studies, demonstrates how acupuncture might work in the human body to reduce stress and pain, and, potentially, depression,” said study author Ladan Eshkevari in a press release.
In the study, published recently in the journal Endocrinology, the researchers tested the effects of electroacupuncture, in which the needles carry a mild electric current, on stressed-out rats. They were targeting the stomach meridian point 36, which is located on the shin in humans, or behind the hind paw in rats. It’s considered in acupuncture to be one of the most powerful points on the body because it influences a pathway for chronic stress pathway called the hypothalamus pituitary adrenal axis.
When the researchers inserted needles at this point on rats that were stressed from cold, their stress hormone levels were much lower compared to those who did not receive the acupuncture treatment. Many drugs used to treat anxiety and depression tap into the same systems of hormones, bolstering the legitimacy of the findings.
If acupuncture works the same way in humans as it does in rats, it would be a promising alternative to medication; acupuncture may have fewer side effects and wouldn’t require so much tinkering with dosage. The researchers hope to test the mechanism in humans in future studies.