Did you know that your skin hosts a community of microorganisms that lives alongside you and interacts with the immune system?
A skin that is lived in
We tend to think of the skin as a barrier between us and the environment. And it is one. It protects the body from harmful microorganisms. At the same time the skin is home to a community of bacteria, fungi and other microorganisms that live with us without causing harm. This community is called the skin microbiota, and its genes as a whole are called the microbiome.
The surface of the skin is a tough place to live. It is dry, acidic and poor in nutrients. These very conditions make life hard for harmful microorganisms. Yet the skin hosts a very diverse community, and understanding how it works puts everyday skincare in a new light.
What the review covers
The work we are discussing is a review published in 2018 in Nature Reviews Microbiology. A review gathers and organizes the findings of many earlier studies.
The authors describe the DNA sequencing techniques used to identify the microorganisms that live on the skin. These techniques can recognize them in great detail, from the broadest group down to the single strain. The review discusses the makeup of skin microbial communities in health and disease, the relationships between species and their interactions with the immune system.
Three key players
The review focuses on three well-studied bacteria. Propionibacterium acnes is best known for its link with acne. Staphylococcus epidermidis is a common resident of healthy skin. Staphylococcus aureus is known for its role in several skin conditions.
The underlying message is that the skin hosts an ecosystem, with balances between different species and a constant dialogue with the body’s defenses. The same microorganism can behave differently depending on the context it lives in.
How to read this work
As a review, this article offers a map of what was known at the time of publication. Research on the skin microbiome is moving fast and many questions remain open, especially about how these balances translate into practical advice.
What can be said with caution is that the skin does not live alone. Very harsh cleansing or routines with too many products change the environment these microorganisms live in. If your skin suddenly changes or gives you discomfort that does not go away, see a dermatologist, who can assess your situation.
This article is for information only. It does not replace the advice of a doctor or dermatologist, whom you should consult with any question about your skin.