Introduction
Sweat is the watery secretion secreted by certain sweat glands of some parts of the body. Its function is to regulate body temperature and, through the sexual scents (pheromones) it contains, also to signal during sexual activity.
Composition of sweat
Sweat consists almost exclusively of water and salt. Other minerals found in sweat are sodium, chloride, potassium, lactate, certain amino acids and urea. Proteins and sugar are also found in sweat. In addition to proteins, a not inconsiderable number of lipids, i.e. fats, are also found in sweat.
The sweat glands
Sweat glands are skin appendages that occur almost on the entire surface of the human body. Exceptions are the lip and the male glans. They have a diameter of 0.4 mm, reach into the subcutis and their number is over one million.
Their task is to secrete sweat, which is regulated by the vegetative nervous system. Some glands have assumed special tasks and are called modified sweat glands. These include the scent glands, eyelid glands and ear wax glands.
There are two different types of sweat glands: 1. eccrine sweat glands The eccrine sweat glands are distributed over the entire surface of the body and produce the secretion that is commonly called sweat. This is a clear liquid that consists of over 99% water. Other components of sweat are mainly hypotonic, as the ions (components besides water) are present in relatively low concentrations.
The pH-value fluctuates between 4 and 7 due to various factors that influence it, but is usually around 4.5 (i.e. in the acidic pH range). Fresh sweat is first of all odorless. The unpleasant, pungent odor attributed to it is only due to the fact that the long-chain fatty acids contained in it are converted by the bacteria of the natural skin flora into shorter molecules such as formic or butyric acid, which ultimately provide the typical odor.
- Eccrine and
- Apocrine sweat glands
- Electrolytes such as sodium and chloride ions (responsible for the salty taste of sweat), potassium, magnesium and phosphate
- Lactate
- Urea
- Uric acid
- Amino acids
- Cholesterol and
- Fatty acids
2. apocrine sweat glands In addition, there are the apocrine sweat glands, which are actually scent glands. These are found only in certain places (namely, only in hairy areas, since apocrine sweat glands always occur in conjunction with a hair shaft), for example, in the armpits, nipples and genital area. These glands only develop during puberty and secrete a secretion that is rather milky and cloudy, contains many fragrances, proteins and lipids and has a roughly neutral pH value of 7.2.
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