The full moon's supposed influence on human behavior is one of the most studied topics in psychology and medicine. A landmark 1986 meta-analysis synthesized roughly 100 individual studies and found no evidence of a causal link between lunar phases and human behavior — a finding that set the tone for decades of follow-up research.
Since then, large-scale studies have examined ER admissions, psychiatric hospitalizations, crime rates, and ambulance call volumes across lunar cycles. Reviews published in NIH-indexed journals consistently report null results: no meaningful increase in emergency visits, psychiatric crises, or violent incidents during full moons. A study cited by Parkland Medical Center, for instance, concluded there was "no link between increased ER visits and the full moon."
Despite this volume of negative evidence, isolated studies occasionally report small correlations in narrow subgroups — such as minor sleep disruption — but these findings are inconsistent and not replicated at scale. The scientific consensus, built on hundreds of studies, is that the full moon does not cause unusual human behavior.