The present disclosure provides a method of using a sweat sensing device to determine a kidney profile for an individual. The method includes taking concentration, ratio, and trend measurements of one or more kidney biomarkers in the individual's sweat, along with other contemporaneous device measurements to inform sweat rate, skin temperature, sweat sample pH, or other factors. The method further considers these measured values in the context of external information about the individual, and uses such information to develop a kidney function profile or a kidney injury profile indicative of the physiological state of the individual.