Sweat contains the chemicals or odorants 2-methylphenol (o-cresol) and 4-methylphenol (p-cresol), as well as a small amount of urea.
In humans, sweating is primarily a means of thermoregulation, although it has been proposed that components of male sweat can act as pheromonal cues.
There is widespread belief that sweating, for example, in a sauna, helps the body to remove toxins, but the belief is without scientific support.
Evaporation of sweat from the skin surface has a cooling effect due to the latent heat of evaporation of water. Hence, in hot weather, or when the individual's muscles heat up due to exertion, more sweat is produced.
Sweating is increased by nervousness and nausea and decreased by cold. Animals with few sweat glands, such as dogs, accomplish similar temperature regulation results by panting, which evaporates water from the moist lining of the oral cavity and pharynx.