Have you ever used the expression “sweat like a pig”? Think again. Pigs don’t sweat. Pigs don’t have sweat glands, which explains why they have to wallow in puddles and mud to cool off.
As for us humans, we routinely sweat as a way of eliminating excess heat and maintaining a normal body temperature. The average person has 2.6 million sweat glands distributed over the entire body except for the lips, nipples, and external genitalia.
There are two different types of sweat glands, eccrine and apocrine. These glands are different in size and produce different kinds of sweat. Eccrine glands are located all over the body. Apocrine glands are different because they are found mostly in the armpits and groin. They are larger and open into hair follicles. Though sweat is mostly water, it is the small amount of protein and fatty acids in the apocrine sweat glands that gives armpit sweat that wonderful milky or yellow color. It is also what causes it to stain.
Sweat itself is odorless whether it comes from the armpits or other areas of the body. The funk begins when sweat mixes with bacteria that occur naturally on the surface of the skin. This distinctive odor is called bromhidrosis—foul-smelling sweat.
Why Do Your Teeth Chatter When You Are Cold?
The body usually maintains a constant temperature of 98.6 degrees Fahrenheit. At this temperature the cells of the body work best. If there is any significant change in temperature, it is sensed by an area of the brain called the hypothalamus.
When the body gets too cold, this center alerts the rest of the body to begin warming up. Shivering, the rapid movement of the muscles to generate heat, then begins. Teeth chattering represents localized shivering.
Culled from “Why do men have nipples? : hundreds of questions you’d only ask a doctor after your third martini / Mark Leyner and Billy Goldberg.”