Analysis system, comprising a toothbrush with a brush head (1, 20, 30, 40, 50), having at least one mechanical cleaning agent for cleaning the teeth and a plurality of sensor units (4, 5, 8, 42, 51) for monitoring the state of health of a user, wherein the brush head (1, 20, 30, 40, 50) has a first sensor unit for performing an impedance measurement of the saliva with one or more frequencies and/or frequency bands, wherein the brush head (1, 20, 30, 40, 50) has at least one second sensor unit for determining the pH value and/or the temperature of saliva, and wherein the brush head has a third sensor unit, wherein the third sensor unit is designed as a biosensor and wherein the third sensor unit is arranged in an exchangeable manner on or in the brush head (1, 20, 30, 40, 50) and has an external device for data processing, wherein the toothbrush comprises a radio module for data transmission to the external device for data processing to determine a state of health, so that raw signals can be transmitted from the toothbrush to the external device, and wherein the external device comprises a data memory on which a computer program product for data analysis is stored, wherein the computer program product is designed for analyzing the data determined by the sensor unit designed as a biosensor, preferably according to one or more DSP methods, for determining a state of health, wherein the data analysis comprises the following steps: a. sampling impedances over a measurement period at a predetermined sampling rate; b. detecting and classifying states of the sensor units (4, 5, 8, 42, 51) with regard to the moisture state of the sensor units (4, 5, 8, 42, 51) on the basis of the impedances determined; and c. evaluating amplitudes and/or changes in the impedances, and in particular the associated redox reactions and/or capacitive transients, in order to analyze the saliva with regard to the state of health of the user, wherein, on the basis of the impedances determined, the presence of toothpaste and the concentration of saliva in water are detected in addition to the humidification state. wherein the brush head (1, 20, 30, 40, 50) has at least one second sensor unit for determining the pH value and/or the temperature of saliva, and wherein the brush head has a third sensor unit, wherein the third sensor unit is designed as a biosensor and wherein the third sensor unit is arranged in an exchangeable manner on or in the brush head (1, 20, 30, 40, 50) and has an external device for data processing, wherein the toothbrush comprises a radio module for data transmission to the external device for data processing to determine a state of health, so that raw signals can be transmitted from the toothbrush to the external device, and wherein the external device comprises a data memory on which a computer program product for data analysis is stored, wherein the computer program product is designed for analyzing the data determined by the sensor unit designed as a biosensor, preferably according to one or more DSP methods, for determining a state of health, wherein the data analysis comprises the following steps: a. sampling impedances over a measurement period at a predetermined sampling rate; b. detecting and classifying states of the sensor units (4, 5, 8, 42, 51) with regard to the moisture state of the sensor units (4, 5, 8, 42, 51) on the basis of the impedances determined; and c. evaluating amplitudes and/or changes in the impedances, and in particular the associated redox reactions and/or capacitive transients, in order to analyze the saliva with regard to the state of health of the user, wherein, on the basis of the impedances determined, the presence of toothpaste and the concentration of saliva in water are detected in addition to the humidification state. a. sampling impedances over a measurement period at a predetermined sampling rate; b. detecting and classifying states of the sensor units (4, 5, 8, 42, 51) with regard to the moisture state of the sensor units (4, 5, 8, 42, 51) on the basis of the impedances determined; and c. evaluating amplitudes and/or changes in the impedances, and in particular the associated redox reactions and/or capacitive transients, in order to analyze the saliva with regard to the state of health of the user, wherein, on the basis of the impedances determined, the presence of toothpaste and the concentration of saliva in water are detected in addition to the humidification state.