How Sweating Works
Sweating is the bodies way of cooling itself, it does not matter where the heat comes from the body attempts to shed the heat with sweating. For example when doing exercise the contracting muscles produce a lot of heat which needs to be evaporated away to keep the body at its optimal temperature.
There are approximately 2.6 million sweat glands in the skin which help to bring moisture to the skin, and they are all over the body and more heavily concentrated in certain regions. The sweat gland is embedded within dermis skin layer.
The sweat gland is a long, coiled, tube of cells. The coiled part is where the sweat is created and the long tube like structure is the canal it goes through to get to the skin. Nerve cells from the sympathetic nervous system are connected to the sweat glands and control their action. There are two types of sweat glands. The Eccrine sweat gland is the one which is the most common, it can be found in particular on palms, soles and forehead. These are active for your entire life and when they are stimulated they produce sodium chloride, and a minute trace of potassium. There is also the apocrine sweat glands which are confined to the armpits and the private area, they have a particular phenotype in that they end in a hair follicle as opposed to a pore. The consistency of the sweat is slightly different, as well as sodium chloride and potassium the sweat also contains trace amounts of fatty acids and proteins. This is the reason of the strong smell as bacteria thrive on this. These extra ingredients also give rise to the yellow tint that can result from the staining of white clothing by armpit sweat.
Two modes of operation
- Low sweat production - this is the resting state when we are cool and in this case the cells in the straight duct absorb the majority of liquid from the fluid as is enough time for reabsorption and not too much fluid produced. This means that in this mode it is not even noticed that we are sweating.
- Heat sweat production - during exercise or a hot temperature or when excessive sweating is being triggered, now the cells in the tube portion do not have enough time to absorb all the moisture coming through so most of it makes its way to the surface of the skin.