Perspiration is a vital bodily fluid secreted by sweat glands in mammals for temperature regulation and other physiological functions.
How Sweating Works
The human body contains two distinct types of sweat glands: eccrine glands and apocrine glands. Eccrine glands cover most of the body and produce watery sweat for cooling. Apocrine glands, found mainly in armpits, create an oily secretion that bacteria break down, causing body odor.
Temperature Regulation
The human body can produce remarkable amounts of sweat – up to 4 liters per hour or 14 liters daily. This sweating cools the body through evaporation. When sweat evaporates from the skin, it removes heat energy, lowering body temperature.
Sweat Composition
Human sweat consists mainly of water with small amounts of:
- Sodium (0.9 g/L)
- Potassium (0.2 g/L)
- Calcium (0.015 g/L)
- Magnesium (0.0013 g/L)
Medical Implications
Hyperhidrosis
Hyperhidrosis affects millions of people, causing excessive sweating primarily in armpits, feet, and hands. While not life-threatening, it significantly impacts quality of life. Treatment options include:
- Antiperspirants
- Iontophoresis
- Surgical removal of sweat glands
- Botulinum toxin injections
Night Sweats
Nocturnal hyperhidrosis, or night sweats, often signals underlying medical conditions. In women over 40, it commonly relates to menopause. Severe cases warrant medical investigation as they may indicate serious conditions.
Antimicrobial Properties
Sweat contains dermcidin, a protein that fights harmful microorganisms like E. coli and S. aureus. This natural antimicrobial function helps protect the skin from infections.
Modern Applications
Scientists have developed artificial skin capable of sweating for research purposes. Wearable technology can now monitor sweat composition continuously, though challenges remain with sample volumes and filtration. The main medical application is testing infants for cystic fibrosis using sweat chloride measurements.
https://en.wikipedia.org/wiki/Perspiration
This article about biology may be excessively human-centric. |
Perspiration, also known as sweat, is the fluid secreted by sweat glands in the skin of mammals.
| Perspiration | |
|---|---|
| Other names | Sweating, hidrosis, diaphoresis |
 | |
| Droplets of perspiration on the skin | |
| Specialty | Dermatology |
| Symptoms | Body odor |
| Complications | Dehydration |
| Causes | Exercise Fever Heat Hyperthermia Hot flash |
| Prevention | Drinking water |
| Treatment | Antiperspirant |
Two types of sweat glands can be found in humans: eccrine glands and apocrine glands. The eccrine sweat glands are distributed over much of the body and are responsible for secreting the watery, brackish sweat most often triggered by excessive body temperature. Apocrine sweat glands are restricted to the armpits and a few other areas of the body and produce an odorless, oily, opaque secretion which then gains its characteristic odor from bacterial decomposition.
In humans, sweating is primarily a means of thermoregulation, which is achieved by the water-rich secretion of the eccrine glands. Maximum sweat rates of an adult can be up to 2–4 litres (0.5–1 US gal) per hour or 10–14 litres (2.5–3.5 US gal) per day, but is less in children prior to puberty. Evaporation of sweat from the skin surface has a cooling effect due to evaporative cooling. Hence, in hot weather, or when the individual's muscles heat up due to exertion, more sweat is produced. Animals with few sweat glands, such as dogs, accomplish similar temperature regulation results by panting, which evaporates water from the moist lining of the oral cavity and pharynx.
Although sweating is found in a wide variety of mammals, relatively few (apart from humans, horses, some primates and some bovidae) produce sweat in order to cool down. In horses, such cooling sweat is created by apocrine glands and contains a wetting agent, the protein latherin which transfers from the skin to the surface of their coats.