In 1913 Dr. William Fitzgerald noted that pressure on specific parts of the body could have an anaesthetising effect on a related area. Developing this theory, he divided the body into ten equal and vertical zones, ending in the fingers and toes. He concluded that pressure on one part of a zone could affect everything else within that zone.

In the 1930's, Eunice Ingham, a therapist, further developed and refined the zone therapy into what is now known as reflexology. She observed that congestion or tension in any part of the foot mirrors congestion or tension in a corresponding part of the body. Thus, when you treat the big toes there is a related effect in the head, and treating the whole foot can have a relaxing and healing effect on the whole body.