Sweat Sense: Low-Cost Non-Invasive Arduino-Based Conductivity Monitoring for Dehydration Detection

Dehydration due to excessive sweating is a major concern for athletes, outdoor workers, elderly people, and individuals with health conditions such as cardiovascular disorders. Since sweat contains dissolved salts, mainly sodium chloride, monitoring salt loss can help in understanding hydration status and preventing electrolyte imbalance. The aim of this experiment is to study the relationship between salt concentration and electrical conductivity using a simple conductometric method. In this work, water and sodium chloride solution are used as test samples to observe how dissolved ions influence conductivity and total dissolved solids. The experiment supports the concept that salt concentration in sweat-like fluids can be estimated through conductivity measurement using low-cost sensing components. This study provides a basic experimental foundation for developing a non-invasive sweat monitoring system. By integrating conductivity electrodes, signal conditioning, Arduino-based data acquisition, temperature compensation, and calibration equations, the method can be further extended into a wearable sweat band for real-time dehydration alerting. Such a device may be useful for sports persons, workers exposed to heat, and medically vulnerable users who require timely rehydration support. In conclusion, this work highlights the possibility of using conductance-based salt detection for preventive hydration monitoring, and we are interested in continuing this study toward the development of a practical wearable sweat band device.