In addition to water, what is lost in sweat?

Sweat primarily consists of water, but it also contains various dissolved substances that are essential for body function. One of the most significant components lost in sweat is salt, which is mainly composed of sodium chloride. The loss of salt through sweat plays a crucial role in regulating body temperature and maintaining electrolyte balance during physical exertion or heat exposure. When the body sweats, the evaporation of water helps cool the skin, but this process also results in the loss of salt, which can lead to an imbalance if fluid and electrolyte intake does not compensate for this loss. Therefore, understanding the role of salt in sweat is critical for maintaining hydration and overall health, particularly in field conditions where maintaining electrolyte balance is vital for performance and safety.