Sweating

Sweating, or perspiration, is a normal phenomenon in humans.

Sweating and Heat Loss

The evaporation of the water from the skin takes heat away from the body and so sweating is essential for our temperature control. If we didn't sweat at all, we could overheat especially after exercise or on very hot days.

In the animal kingdom, we find that humans are the smallest animals that sweat.

Larger animals, such as elephants, depend on sweating as well as other behavioural patterns to control their temperature. Such behaviours include putting dirt over their backs to protect their skin from the sun, staying in the shade or going into water when available. Elephants also flap their ears to radiate heat out of the blood that flows through the blood vessels in the ears.

Smaller animals, such as dogs, cannot sweat and as such have to lose heat in other ways - for example dogs get rid of heat by panting. When they pant, the movement of air causes evaporation of the water off of the dog's tongue cooling the blood in the tongue, which then circulates and cools the dog.

Sweat Glands - Eccrine and Apocrine Sweat Glands

Sweat is produced from the "Sweat Glands" - the watery sweat comes from the Eccrine glands deep in the dermis (skin) and the more greasy type of sweat that can smell comes from the Apocrine glands, that are usually found around the hair follicles.

Sweat and Toxins Removal

Sweat is mainly water. As it is produced from the blood, it does have some salts in it - sodium ions, chloride ions and urea. In people with heavy metal poisoning, some of the metal can be found in the sweat. However, despite many people thinking that sweat gets "rid of the toxins", it is not a major way for the body to remove toxins.

The Control of Sweating in the Body

The control of sweating in the human body is mainly via the sympathetic nervous system.

The first nerve runs from the brain, down the spinal cord and then comes out and communicates with a second sympathetic nerve which lies in the sympathetic chain.

The sympathetic chain lies on the bone of the spinal column. This second nerve then runs from the sympathetic chain to the skin where it connects to the sweat glands.

Of course, adrenaline and noradrenline, the stress hormones, are also released by the sympathetic nervous system as part of the "fight or flight" mechanism. These hormones also have an affect on the system.

To be able to treat excessive sweating - called "hyperhidrosis" - it is essential to understand this chain. The treatments for excessive sweating or hyperhidrosis all work on certain parts of this chain.

Good understanding is therefore essential to understand which treatment is necessary for which condition.