Acupuncture's clinical claims have drawn more controlled research than any other East Asian healing art, in part because inserting a needle is easier to test against a plausible sham than most other traditional therapies. Western clinical interest surged after a well known 1971 newspaper account described acupuncture anesthesia during coverage of Richard Nixon's trip to China, and by the 1990s the United States National Institutes of Health had convened a consensus panel that found the evidence supportive for some conditions, notably postoperative and chemotherapy-related nausea and certain kinds of pain, while calling evidence for most other uses insufficient.
Since then a large body of sham-controlled trials, several pooled in a widely cited 2018 individual patient data meta-analysis of chronic pain, has consistently found small but statistically real advantages of acupuncture over sham needling for conditions including back and neck pain, osteoarthritis, and migraine prevention, with benefits persisting for at least a year in some trials. The gap between real and sham needling is small enough, however, that some researchers argue it reflects imperfect blinding or a genuinely active placebo response to a ritualized, hands-on treatment rather than a needling-specific effect tied to any particular point or meridian. The World Health Organization added a chapter on traditional medicine, including practices related to acupuncture, to its International Classification of Diseases in 2019, a decision that drew public criticism from scientists who warned it risked lending unearned legitimacy to unproven diagnostic categories bundled alongside the better-tested uses of acupuncture itself.