OBJECTIVES: This article describes interaction of the Earth's mass-electrolytic conductor on the electrical environment of human organism-aqueous environment and skeleton. In this environment, bioelectrical and bioenergetical processes take place. METHODS AND SUBJECTS: Measurements of electric potential on tongue, teeth, nails, and in venous blood in subjects earthed and unearthed were conducted in Faraday's cage with the use of an electrometer placed outside the cage. Measurements were performed in subjects in lying position and in movements of standing up and lying down. RESULTS: In the unearthed human organism in the lying position, electric potential measured in examined points is around 0? mV. Contact of the Earth by a copper conductor with a moistened surface of the human body evokes a rapid decrease of electrostatic potential on the body and in venous blood to the value of approximately -200 ?mV. This effect is immediate and general. Interruption of contact with the Earth causes a rapid return of the potential to its initial values in examined points. Changes in electric potential measured in venous blood and on mucosal membrane of the tongue reflect alterations in electric potential of the aqueous, electrical environment. Up-and-down movement of the insulated human organism causes transient changes in potential in the human electrical environment. During the same movement, values of potential in the electrical environment of an earthed human body remain constant. CONCLUSIONS: These results indicate that up-and-down movement and the elimination of potentials in the electrical environment of the human organism by the Earth's mass may play a fundamental role in regulation of bioelectrical and bioenergetical processes. The Earth's electromagnetohydrodynamic potential is responsible for this phenomenon.