Sweat
introduction
Sweat is the watery secretion that is secreted by humans from certain sweat glands in some parts of the body. Its task consists in the regulation of the body temperature and through the sexual fragrances (pheromones) contained in it also in the signaling effect during sexual life.
Composition of sweat
Sweat consists almost entirely of water and salt. Further Mineralsthat are found in sweat are sodium, chloride, potassium, Lactate, certain amino acids and urea.
Proteins and sugar are also found in sweat. In addition to the proteins, there are also a not inconsiderable number of lipids, that is Fats, in the sweat before.
The sweat glands
Sweat glands are appendages of the skin that occur on almost 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 a million. Their job is the secretion of sweat, which is regulated by the autonomic nervous system. Some glands have special tasks and are known as modified sweat glands. These include the scent glands, eyelid glands and wax glands.
Types of sweat glands
There are two different types of sweat glands:
- ekkrine and
- apocrine 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 referred to as sweat. This is a clear liquid that consists of over 99% water. Other components of sweat are above all
- Electrolytes such as sodium and chloride ions (responsible for the salty taste of sweat), potassium, magnesium and phosphate
besides that
- Lactate
- urea
- uric acid
- amino acids
- Cholesterol and
- Fatty acids
Since the ions (components in addition to water) are present in a comparatively low concentration, the sweat is hypotonic. The pH value fluctuates between 4 and 7 due to various factors that influence it, but is usually usually around 4.5 (i.e. in the acidic pH range).
Fresh sweat is initially odorless. The unpleasant pungent odor that is attributed to it is due to the fact that the long-chain fatty acids it contains are converted by the bacteria of the natural skin flora into shorter molecules such as formic or butyric acid, which ultimately create the typical odor.
2. Apocrine sweat glands
There are also the apocrine sweat glands, which are actually Scent glands are. These are coming only in certain places before (namely exclusively on hairy areasbecause apocrine sweat glands always in conjunction with a hair shaft occur), for example in the area of Armpits, Nipples and the genitals. These glands arise only in the context of the puberty and secrete a secretion that is rather milky-cloudy, many Fragrances, proteins and Lipids contains and one about neutral pH of 7.2 Has.
Sweat production
The basic secretion (basic amount) of sweat, i.e. the amount of sweat that is always produced regardless of external conditions, is around 100 to 200 ml daily in humans. However, this volume can be strongly influenced by various factors and therefore vary.
Causes of increased perspiration
The most important stimulus for increased secretion of sweat is probably a high ambient temperature. Physical exertion and psychological conditions such as stress or excitement are further triggers for stimulating the production of sweat.
The high adaptability of the sweat glands means that when such influences are present, the amount of sweat produced can rise to 2 liters per hour. The concentration of salt is then reduced more and more in order to protect the body from excessive salt loss.
On the neural level, the increased sweat production can be explained by increased activity of the sympathetic nervous system. The sympathetic nervous system acts on the sweat glands via certain transmitters and stimulates them to secrete.
Importance of sweat for the body
Sweat fulfills several tasks in the human body. The most important is the regulation of body temperature. Because sweat is secreted from the glands to the surface of the skin, this is always covered by a thin film of liquid at high ambient temperatures.
This can now evaporate, i.e. change from the liquid state to water vapor, whereby the body loses a large amount of energy and thus heat, which leads to so-called evaporation cold. Dripping sweat is pointless with regard to this function.
Aside from the sweating that we notice on the skin (Perspiratio sensibilis) there is also the unnoticed form of "sweating" (Perspiratio insensibilis), for example the evaporation of liquid via the breath (i.e. via mucous membranes).
As sweat spreads over the skin like a film, it acts as a protective acid mantle thanks to its acidic pH value and thus helps to prevent pathogens such as bacteria or viruses from entering the body.
Sweat also has an important signaling effect. It contains certain fragrances. These include sexual attractants (Pheromones), which contribute to sexual arousal, but also other fragrances that presumably have a warning function in emotional sweating.
Read on under: Pheromones for men
The smell of sweat
Usually sweat is odorless or has little odor. Especially in summer, when temperatures are very high, it happens that you are soaked in sweat, but you don't smell of it at all. The smell of sweat only occurs when the sweat is broken down. This also explains why fresh sweat is odorless and older sweat then begins to smell. The smell comes about through bacterial degradation, which is carried out by bacteria living on the skin and which, among other things, produces butyric acid.
Diet is also involved to a not inconsiderable extent in the odor formation of sweat. If more animal proteins are consumed, a stronger odor can develop when you sweat, even when you have fresh sweat. Furthermore, a vegetative component is added to the odor formation. The sweat that arises during sporting activities and is given off on the skin is often odorless or completely odorless. However, the sweat produced by excitement and fear is often very odorous. The exact reason for this is not clear.
Another exception to the formation of odors is hormonal influences. The composition of sweat during puberty is different from that in adults, which can mean that young people can also smell fresh sweat very quickly.
There are also gender-dependent differences in the odor development of sweat. The sweat of women is less odorous than that of men. Here, too, other compositions of sweat are seen as the cause.
The sweat
A sweat outbreak is a sudden, greatly increased production of sweat, which can have different causes. On the one hand, sweating occurs at high temperatures and during intense sport, which is important for the body, as overheating is counteracted. Sweats can also be psychological in nature. In this case, fear and stress are usually the trigger. Another reason are changes in the hormonal balance, such as those that occur during menopause or pregnancy.
Furthermore, frequent and profuse sweating can be caused by an illness. Examples are diabetes mellitus, hyperthyroidism, obesity, cancer and various metabolic diseases. Acute events, such as heart attacks, pulmonary embolisms or fainting spells, can also trigger sweating. In order to treat sweats, the reason should always be clarified first, as different treatments are preferable depending on the cause.
Sweaty hands
Like the feet, the palms of the hands have a high density of sweat glands, so it is not surprising that sweaty hands are a common problem. This can even have psychological effects, as those affected feel ashamed of their sweaty hands when they shake hands, for example, or do not want to touch things like doorknobs or glasses. Sweaty hands usually occur in stressful or embarrassing situations. In these states the sympathetic nervous system is activated, which also causes increased sweating and is hardly controllable by consciousness.
The reasons for the overactive sweat glands are mostly of genetic origin, which is why not everyone has to be affected and the severity varies greatly. Nowadays there are a variety of therapies for treating sweaty hands, which can often be used to remedy the problem. Some of these are acupuncture, aluminum chlorine-containing ointments or botox injections at the dermatologist. Which of these is the means of choice should always be clarified individually.
Sweaty feet
Sweaty feet occur when there is increased sweat production in the foot region, which can cause an odor to develop after a while, which is why the term cheese feet is used colloquially. In contrast to the body's skin, perspiration does not regulate body temperature here. Instead, the sweat glands on the soles of the feet are controlled by the autonomic nervous system, which is particularly active in fearful and stressful situations. From a functional point of view, the sweat on the foot should ensure better adhesion to smooth surfaces. The sweat glands often overfunction, which is why those affected constantly complain about wet feet. In addition, the moisture and warmth provide optimal conditions for bacteria, which multiply and cause an unpleasant, cheesy odor through decomposition processes.
There are a few tips to help reduce sweaty feet. On the one hand, that would be walking barefoot, as it allows the sweat to evaporate better. You should also pay attention to hygiene. This includes washing your feet regularly, then drying them off and applying cream to your feet. If there is no improvement, special ointments with aluminum chloride are available in pharmacies.
Read more on the topic: Sweaty feet
Sweat pimples (heat rash)
Especially in the Summer monthsIf you sweat a lot and often, it often happens that there are small spots in the areas that are usually heavily covered with sweat Pimples form. Most often the forehead, cheeks or back are affected. Also called Heat rash The change in the skin indicated is usually only visible until the body's sweat production has been reduced or stopped entirely.
The reason for this heat or sweat pimple is above all one Overproduction of sweat. When the body produces excessive sweat and releases it to the skin through the pores, it can clog the pores. The skin that lies directly around the pores can then swell, which can then generally be seen as a small lump or pimple. These types of pimples are different from the typical acne pimples not pus-filled. Sometimes a noticeable reddening can surround the pimples. In some cases it can lead to a slight itching come. The heat rash usually disappears as quickly as they came and when the body's sweat production has been reduced again. A separate one treatment is generally unnecessary.
Sweat allergy
Allergies can be caused by a wide variety of substances. The body's own sweat is also part of it, in which case one speaks of a pseudo-allergy, since the immune cells do not react to the sweat itself, but to the increased body temperature. The body mistakenly tries to combat the physical stimulus through an immune reaction by releasing substances such as histamine. This then leads to itching, reddening of the skin and the formation of wheals on the affected skin areas.
It is often not easy to clearly prove a sweat allergy. Doctors usually use an exercise test to make a diagnosis. The exertion increases the body temperature and the skin reactions described occur.
Sometimes it happens that the skin starts to redden after profuse sweating. Long-lasting and unpleasant itching can also occur. The reason for this is irritation of the skin cells, which can be caused by the special irritating composition of sweat. In the broadest sense, it is more an irritation than an allergy.
As soon as the sweat has been wiped off the skin and the body's sweat production has been reduced, the reddish skin changes begin to recede. This can take a few hours, as the epidermis usually recovers relatively slowly. There are no preventive measures. The only thing you can do is often wipe off the sweat with a damp cloth if you sweat heavily. The sweat allergy occurs particularly frequently in places that are mostly covered by sweat. This includes the forehead, arms, back and chest.
A sweat allergy cannot be fully treated, but something can be done about the symptoms. On the one hand, the lifestyle should be adjusted and excessive exertion such as sport should be avoided or reduced. In addition, the release of histamine can be treated with an antihistamine.
Would you like to learn more about this topic? Then you might be interested in: Sweat allergy - causes, consequences, treatment
Pathology associated with sweat
There are some diseases that are related to abnormal secretion of sweat. If a person produces too much sweat, one speaks of hyperhidrosis and, if too little, of hypohidrosis.
On the other hand, if there is no sweat secretion, anhidrosis is present. So-called cold sweating (sweating despite cool skin) occurs as an accompanying phenomenon to some serious illnesses (for example heart attacks) and should always be understood as a warning signal