Why Do We Smell When We Sweat?

When people exposed to heat, through experiencing elevated air, temperature, exercise or emotional stress, they often sweat. Sweating is the body’s way of cooling itself off, whether a person is stressing over a big test. Sweat comes from the 2.6 million sweat glands in the skin. However, the degree to which people sweat and the resulting smell that is produced varies greatly.

The skin has two types of sweat glands: eccrine and apocrine. The skin contains millions of eccrine glands distributed all over the body, and the fluid that they produce consists mainly of salt and water and has no smell. Appocrine glands meanwhile tend to locate in areas where there are lot of hair follicles and the sweat they produce is fatty.

Sweat only begins to smell and cause the unpleasant odors when the bacteria living on our skin and clothes deign to break it down to produce the fatty acids they feed on. Sweat is almost completely of water with tiny amounts of other chemicals like ammonia, urea, salts and sugar. When the sweat hits the air, the air makes it evaporate. As the sweat evaporates off the skin and cool down.

Sweat itself is odorless whether it comes from the armpits or other areas of the body. The smelliness begins when sweat mixes with bacteria that occur naturally on the surface of the skin. This distinctive odor is called bromhidrosis -foul smelling sweat.