What substances to sweat glands release?

Sweat glands release water, electrolytes, urea, lactic acid, fatty acids, amino acids, glucose, and protein. The composition of sweat varies depending on the location of the sweat glands and the body's hydration status. For example, sweat from eccrine glands is hypotonic, meaning that it has a lower concentration of solutes than blood plasma, while sweat from apocrine glands is more concentrated. Eccrine sweat is also responsible for thermoregulation and cooling the body, while apocrine sweat primarily serves a pheromonal function.