Reflexology, or zone therapy, is an alternative medicine involving the physical act of applying pressure to the feet, hands, or ears with specific thumb, finger, and hand techniques without the use of oil or lotion. It is based on what reflexologists claim to be a system of zones and reflex areas that they say reflect an image of the body on the feet and hands, with the premise that such work effects a physical change to the body. A 2009 systematic review of randomised controlled trials concludes that "The best evidence available to date does not demonstrate convincingly that reflexology is an effective treatment for any medical condition."
There is no consensus among reflexologists on how reflexology is supposed to work; a unifying theme is the idea that areas on the foot correspond to areas of the body, and that by manipulating these one can improve health through one's qi. Reflexologists divide the body into ten equal vertical zones, five on the right and five on the left. Concerns have been raised by medical professionals that treating potentially serious illnesses with reflexology, which has no proven efficacy, could delay the seeking of appropriate medical treatment.