Placebo activates Endorphins to relieve Pain

Society for Neuroscience News Releases: "Considerable evidence indicates that the endogenous opioid, or endorphin, system plays a role in placebo effects—the therapeutic benefits obtained after the introduction of an inert substance—that are suggested to reduce pain. Implied pain-relieving placebos have also been associated with reductions in subjects' ratings of their own pain. The release of endorphins is the body's natural way of killing pain."