The method and system for evaluating the effect of weather, geomagnetic background and the air on the condition of a person's body—involves the input of personal data—by a computer device user; the determination or specification of a geolocation; the transmission of the personal data and the geolocation data, to a processing unit; the requesting of environmental forecast data from a weather server; the transmission of the forecast data; the transmission of the user and forecast data to an encoder and the generation of a single hash code; the transmission of the hash code to a decoder and the correlation with a database of dependencies of the functioning of human body systems on weather, geomagnetic background and air condition parameters; and the transmission of the correlated data to a display—and the display of information about the effect of environmental parameters on the functioning of human body systems.