The microbiome - a unique ecosystem
Anyone interested in beauty in general and skincare in particular will encounter the term 'skin barrier' more and more frequently. Whether in women's magazines, pharmacy journals, beauty blogs, or on Instagram accounts: protecting the skin barrier is the latest trend and top of the to-do list for healthy, youthful-looking skin. In this context, the microbiome is also repeatedly mentioned. But what exactly is it? How does it work? And what influence does it have on healthy skin and a beautiful complexion?
What is the microbiome?
The microbiome is part of the epidermis. It is a community of microorganisms (bacteria, fungi, viruses, and other microbes) that form a complex ecosystem on the skin. These tiny organisms, invisible to the human eye, live in symbiosis with us and have a major influence on skin health. Fascinatingly, the composition of the microbiome is as unique to each person as their fingerprint. The microbiome also varies across different areas of the body, changes with age, and responds to environmental conditions. There is a clear but complex link between the appearance and health of mature skin and a balanced microbiome. As the skin ages, the diversity and composition of microorganisms change. Living in a city or the countryside also plays a crucial role: people in rural areas often have greater microbial diversity than city dwellers. Western civilization has lost much of its bacterial diversity on the skin, partly due to urban lifestyles and modern hygiene standards. All these factors make the microbiome a dynamic and complex system that is different in every person.
Why is a healthy microbiome so important?
The microbiome is our very own protective shield. It is healthy as long as the bacteria are in a balanced state and the variety and diversity of species do not decrease. Just like in an ecosystem in nature, the principle of biodiversity applies here as well.
When the microbiome is in balance, the skin benefits in many ways: it protects the skin from potentially harmful germs and environmental influences. It reduces inflammatory processes and supports the skin's own immune system. It regulates the skin's pH level, ensures optimal moisture content, and also strengthens the skin barrier.
If the microbiome becomes unbalanced, the skin may react with dryness, redness, flaking, blemishes, congestion, or pimples—depending on the skin type and which 'resident' is missing or present in excess. Generally speaking, a disrupted microbiome makes the skin more susceptible to dryness, inflammation, and even skin diseases. This makes it look older more quickly.
Factors that influence the skin's microbiome
There are many influences that have an effect on the skin's microbiome—both positive and negative.
Positive factors include a healthy diet rich in antioxidants, e.g. from berries, pomegranate, citrus fruits, cabbage, nuts, and chia seeds. Omega-3 fatty acids (from oily fish such as salmon and mackerel, as well as nuts) also promote healthy-looking skin. In addition to food, drinking is also important for a healthy microbiome: experts say two liters of water a day is the recommended amount. Anyone who wants to do something good for their well-being and skin should avoid nicotine. Nicotine can disrupt the balance of the microbiome, leading to an imbalance between beneficial and harmful microorganisms.
Another factor is skincare. Gentle formulations for cleansing and care are beneficial. This includes harsh surfactants such as sodium lauryl sulfate (SLS), which wash away beneficial microbes. Antimicrobial substances such as triclosan and benzalkonium chloride can also remove not only harmful but also protective bacteria. Even alcohol, which is contained in almost every cleansing product, should be avoided—isopropyl alcohol is particularly noteworthy, as it dries out the skin. Care should also be taken with preservatives, as they can disrupt the skin flora.
Washing the skin too frequently is considered a negative influence on the microbiome. Anyone who cleanses their face and body with hot water and irritating products removes beneficial bacteria and strips the skin of valuable fats that keep it supple. The alternative: use better-formulated cleansing products and lukewarm water. Do not scrub the face, but gently pat it dry. Use an exfoliant—depending on your skin type—only once a week.
Even environmental influences can upset the microbiome. UV radiation is the main culprit. Ultraviolet sunlight is a proven danger to the skin. Excessive sunlight damages the microbiome and skin cell DNA. It promotes premature skin aging, which becomes noticeable through, e.g., dark spots and dryness. Air pollution is another additional cause of microbiome problems. Especially in large cities, the skin is exposed to pollutants such as fine particulate matter and soot, which can penetrate the skin and cause oxidative stress, trigger inflammation, and accelerate skin aging (so-called photo-aging).
Even mental health is linked to the microbiome. For example, the stress hormone cortisol can create unfavorable changes in the environment, promoting the growth of potentially harmful bacteria to the skin. If the stress is chronic, the skin barrier suffers as it becomes more permeable, making it easier for bacteria to penetrate from the outside and throw the microbiome out of balance. This also increases susceptibility to inflammation.
If we change our lifestyle habits, our skin microbiome will also change in just a few months! We can therefore actively contribute to our skin health! The latest research shows that forest bathing provides a major benefit. The Japanese tradition of 'shinrin-yoku' is said to promote mental well-being while also having a positive effect on the microbiome. Phytoncides (oils released by trees) are believed to have antimicrobial and antiviral properties, which benefit the balance of the ecosystem.
Why prebiotics and probiotics are a must-have for the microbiome
For microbiome-friendly skincare, you should use gentle skincare products tailored to your skin type. They should contain few ingredients to avoid over-treating or irritating the skin.
For more intensive support of the skin's natural ecosystem, there are skincare products focused on restoring and maintaining a healthy skin microbiome. This brings the use of bacterial cultures into focus, which help preserve and balance the skin's bacterial diversity: pre-, pro-, and postbiotics!
Prebiotics: Prebiotics serve as food for the beneficial bacteria already present on the skin. This promotes the growth and activity of beneficial microorganisms on the skin while simultaneously inhibiting the multiplication of fungi.
Probiotics: Probiotics are live microorganisms that are actively applied to the skin. In skincare, the bacteria help optimize the balance of the microbiome and remove harmful bacteria. They can reduce inflammation, strengthen the skin barrier, and improve the appearance of the skin. Lactobacillus is a popular probiotic. Bifidobacterium is also often included in skincare products for a healthy skin barrier to help regulate moisture in the microbiome.
Postbiotics: Postbiotics are bioactive compounds produced by probiotic bacteria during growth and metabolism. Unlike probiotics (which contain live microorganisms) and prebiotics (which serve as food for these microorganisms), postbiotics consist of non-living bacterial products or byproducts. They moisturize the skin, strengthen the skin barrier, and have antioxidant properties.
In summary, healthy skin is due to a healthy microbiome. In other words: a perfect balance between 'good' skin bacteria and high diversity in the skin microbiome leads to healthy, radiant skin.
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