How the Gut Microbiota Affects Atopic Dermatitis

The human microbiome in the gut is increasingly being discussed. The gut microbiota is a highly relevant topic in research because it is associated with a variety of diseases. Some of the conditions it is linked to include:

  • Chronic inflammatory bowel diseases
  • Intestinal infections
  • Type 2 diabetes
  • Obesity
  • Depression

And also, atopic dermatitis is believed to be associated with our digestive tract. Here you will learn what is already known about the influence of the microbiome on the skin.

What exactly is the gut microbiome?

When we talk about the microbiome, we’re referring to many organisms: About 100 trillion bacteria inhabit our gut. The collective of these microorganisms – bacteria, fungi, viruses – forms the human microbiome, without which we couldn’t survive. The numerous bacteria influence our metabolism by aiding in digestion. They produce enzymes that break down important nutrients in a way that our bodies can absorb them.

However, our immune system also depends significantly on the intestinal microbiome. About 80% of all immune cells are located in the gut. The tasks of the gut flora are very diverse, and its impact on health is undisputed. It is known that a high diversity of different bacteria is crucial for a healthy gut flora. However, if the diversity of bacterial strains is low, the microbiome becomes imbalanced, leading to what is called dysbiosis.

The connection between gut and skin

The brain (1), gut (3), and skin (5) influence each other. Important influencing factors and mediators of this gut-brain-skin axis include, among others, nutrition (2) and the barrier function (4) of the skin and gut.

The gut is not an isolated organ but is closely connected to other organs, including the brain and the skin. The so-called “gut-skin axis” describes the shared functions of these two organs and their mutual influence. Both the skin and the gut have important barrier functions. The skin barrier is intended to protect against external influences and moisture loss. In the case of eczema, this protection is not as effective because the skin cells are not as well connected. As a result, the skin becomes dry more quickly and reacts sensitively to certain substances.

A similar barrier exists in the gut as well. The gut barrier’s function includes protecting the organism from toxins and harmful bacteria. However, if the gut barrier function is disrupted, unwanted substances can more easily pass through the intestinal wall. This triggers an inflammatory response in the body, which may manifest as inflamed skin on the body. A healthy gut flora is especially important for regulating the gut barrier.

In cases of atopic dermatitis, the gut flora is imbalanced

In individuals with atopic dermatitis, dysbiosis of the microbiome has been observed in several scientific studies. Compared to people without skin conditions, certain bacterial strains were found in reduced numbers. Among them were bacteria that are anti-inflammatory and important for the intestinal barrier. Conversely, certain bacterial strains were found in increased numbers, which are associated with the development of atopic dermatitis.

In some studies, a connection has also been found between the administration of antibiotics during pregnancy or in early childhood and the later development of atopic dermatitis in the child. Current research suggests that the microbiome may play an important role in the development of atopic dermatitis. These observations and findings are very promising but still need further investigation.

The diversity of the intestine is subject to many influences

Fascinating is not only the intestinal microbiome itself with its relation to the immune system but also its variability. The gut flora can even change within 24 hours. The most important influences include:

  • Nutrition
  • Antibiotics and other medication
  • Age
  • Stress
  • Sport

A relatively new observation is the connection between exercise and the gut. These two parameters likely influence each other. This means that regular physical activity has a positive effect on the gut flora, and a healthy gut flora also positively affects athletic performance.

This newly discovered connection between exercise and the microbiome reflects the current state of research well. Namely, there are many studies showing correlations—a relationship between the microbiome and another factor, such as exercise or the skin. Such connections are promising and exciting. However, this is just the beginning of research. Therefore, one should be cautious with premature conclusions.

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Picture of Neurodermitis App Nia
Neurodermitis App Nia