The Importance of the Skin Microbiome

The skin microbiome has become a popular topic in dermatology and immunology. This group of bacteria in the human body functions as part of the body's defensive barrier, protecting against external aggressions. Learn more in this article!
The Importance of the Skin Microbiome

Last update: 01 June, 2021

The importance of the skin microbiome is something we should all be aware of. It’s a concept that’s dermatologists and immunologists are studying more every day. (However, we shouldn’t confuse the microbiome with the intestinal microbiota, which, although similar, is not the same thing!).

When we talk about a microbiota, we’re talking about microorganisms that live in another larger organism. We have as an example the group of microbes that inhabit the human intestine. However, another concept is the microbiome, which includes microorganisms plus their genetic information.

Thus, the skin microbiome is the set of microorganisms and their genetic material, which is usually found in our skin tissue. Although we may not suspect it, bacteria and fungi live on the skin all the time without causing diseases.

It’s said that the skin microbiome is very large, weighing – if we could weigh it – up to half of our body mass (including the skin itself). This volume functions as a defensive barrier against the outside world. Therefore, the importance of the skin microbiome is very obvious!

What’s in our skin?

For many, the microbiome is part of the definition of skin. Specialists believe we can’t exist without having these microorganisms living there and that, therefore, the concept of “skin” includes them.

The skin is part of a system called the integumentary system. Here we include the skin, the phaneras, the glands, and part of the mucous membranes that extend from the skin into the cavities.

A key function of the skin is protection. In fact, it’s the first physical and immunological barrier available to the body to stop the advance of infections and harmful external agents.

As a physical barrier, it interposes itself with the outside, and as an immunological barrier, we count multiple defense cells that are distributed throughout the skin tissue.

The regulation of homeostasis also finds in the skin a necessary and vital organ. To maintain body temperature, for example, we require the skin to carry out the necessary heat and cold exchanges. At the same time, substances and hormones, such as vitamin D, must pass through the skin to become active.

A woman holding some of her skin
The skin is part of the immune system, as it’s a physical barrier against external agents.

Functions of the skin microbiome

At the beginning of the article, we shared that the skin microbiome is part of the immune system. The set of microorganisms that inhabit the skin contribute to the skin’s barrier functions.

In the same way, this habitat created by common bacteria and fungi repels other harmful external agents that would like to settle there. If a pathogenic bacterium wants to invade the skin, it must first establish competition with the bacteria that are already there.

The skin microbiome has its own pH, i.e. it works at a certain acidity that determines the skin acidity. This pH value is also immunological and serves to create environments inhospitable to certain microbes.

Another function is healing and repairing. When skin lesions appear, healing will depend in part on the health of the microbiome, which will help the scarring process go as smoothly as possible. Inflammation will be controlled if the skin microorganisms are in harmony.

Dermatologist looking at skin
The skin microbiome has several important functions. Among these are infection prevention and repair.

Each part of the skin has its own microbiome

Some scientific studies around the world sought to catalog the skin microbiome to know, with some accuracy, which microorganisms inhabit each region of the body. The findings suggest that each region of the skin has its own microbiome.

Despite the differences between them, the regions are fairly stable over time. This means that the bacteria on the face, for example, tend to remain the same over the years, even when faced with different conditions.

The areas that maintain their populations the most are the oily regions of the skin. A place with a very stable bacterial population is the external auditory canal, which also has fungi as regular inhabitants.

On the contrary, moist regions are more unstable. In the feet, there are changes in the microbiome that aren’t recorded in other similar parts, such as the hands. The explanation lies in the accumulation of moisture, which is a fundamental factor in the growth and development of microbes.

The importance of the skin microbiome

We all have a skin microbiome. It’s not bad. In fact, quite the opposite: it’s necessary!

Thanks to these microscopic organisms, we avoid diseases that could complicate our existence. Therefore, we must understand that proper skincare will have an impact on the care of this habitat and, by extension, will improve our defenses.

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