placebo effect

Placebo effect is the term applied by medical science to the therapeutical and healing effects of inert medicines and/or ritualistic or faith healing manipulations. . When referring to medicines, placebo is a preparation which is pharmacologically inert but which may have a therapeutical effect based solely on the power of suggestion. It may be administered in any of the ways in which pharmaceutical products are administered. Regarding procedures drawing on the placebo effect, psychic surgery and faith healing are two possible examples.
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Noun
1. any effect that seems to be a consequence of administering a placebo; the change is usually beneficial and is assumed result from the person's faith in the treatment or preconceptions about what the experimental drug was supposed to do; pharmacologists were the first to talk about placebo effects but now the idea has been generalized to many situations having nothing to do with drugs
(hypernym) consequence, effect, outcome, result, event, issue, upshot

Any health improvement whose cause is the act of undergoing ministrations rather than any or all of the ministrations.