How our gut feeling influences our overall well-being

From underestimated power organ to central key for health, resilience, and inner balance

Our digestive system is far more than just an organ for processing food. The complex interplay between gut, immune system, and brain has increasingly come into the focus of research – with clear findings: a healthy gut flora contributes significantly to both physical and mental health. It strengthens the immune defenses, supports stress regulation, and even influences our mood. In this blog post, we highlight the central role of gut health and show how nutrition, lifestyle, and targeted measures such as fasting and the intake of pre- and probiotics can positively affect the microbiome.

A CONTRIBUTION BY:

Adrianna Kazimierska 
Nutritional Counseling Marienkron

Gut health – the underestimated center of our well-being

The gut is far more than just a digestive organ. It forms the center of our immune system, influences our mood, and communicates directly with our brain through the so-called gut-brain axis. A healthy gut is essential for the body’s resilience against stress, infections, and chronic diseases.

What promotes gut health is now well researched. A central role is played by the diversity of our diet. Those who regularly consume more than 30 different plant-based foods per week sustainably support the diversity of their microbiota. A high-fiber diet is also crucial: ideally, intake should be at least 30 grams per day to provide sufficient “fuel” for beneficial gut bacteria. In addition, fermented foods such as yogurt, kefir, or sauerkraut help promote healthy bacterial strains. Regular exercise, stress management, and good sleep quality also have a positive effect on the gut flora.

Gut dysbiosis – causes and symptoms of an imbalanced microbiome

When the natural balance of the gut microbiota is disturbed, this is referred to as gut dysbiosis. It can be triggered by various factors, such as antibiotic therapy, which destroys not only harmful but also beneficial gut bacteria. Chronic stress, a diet high in sugar and low in fiber, as well as exposure to environmental toxins, pollutants, and pesticides are also among the common causes of dysbiosis.

The resulting symptoms can be diverse. Many affected individuals suffer from bloating, diarrhea, or constipation – often alternating between them. In addition, newly developed food intolerances, skin problems, mood swings, or an increased risk of infections are not uncommon. A disrupted gut flora can therefore have effects that extend far beyond the gastrointestinal tract.

Diagnosing gut dysbiosis is not straightforward, as there is currently no uniform definition or standardized reference values for a “healthy” microbiota. In cases of persistent symptoms, keeping a food diary can help to identify individual reactions to certain foods and link them to specific symptoms – providing valuable insights into the condition of the gut.

Probiotics – supplements vs. natural foods

Probiotics are live microorganisms that, when consumed in sufficient amounts, can have positive health effects on the body. They can be obtained both through targeted dietary supplements and through fermented foods.

Natural sources include yogurt, kefir, and buttermilk, as well as fermented vegetables such as sauerkraut and kimchi, or fermented soy products like tempeh, miso, and natto. Kombucha is also among the popular probiotic foods.

When taking supplements, it is important to pay attention to quality and composition. Preparations that contain multiple bacterial strains are particularly effective, as synergistic effects can enhance their benefits. It is also advisable to look for acid-resistant formulations and a supportive matrix – as found in so-called synbiotics. Probiotics have proven helpful for conditions such as irritable bowel syndrome, antibiotic-associated diarrhea, or ulcerative colitis, and are recommended in medical guidelines for these indications.

However, caution is advised with certain medical conditions. It is recommended to consult healthcare professionals before taking probiotics, as in some cases they may have counterproductive effects.

Prebiotics – the favorite food of our good gut bacteria

Prebiotics are indigestible food components that specifically support the growth of beneficial bacteria in the gut. Soluble fibers that are fermented in the large intestine are particularly effective, serving as an energy source for our protective bacterial strains.

Many plant-based foods naturally contain prebiotic substances. These include inulin, found abundantly in chicory, Jerusalem artichokes, and artichokes, as well as fructooligosaccharides (FOS), present in onions, garlic, and bananas. Resistant starch, found in green bananas, cooled potatoes, or hearty oats, is also among the most effective prebiotics. Other important sources include beta-glucans from oats, barley, and certain mushrooms, as well as pectin from apples with skin or carrots.

In certain cases – such as diets very low in fiber or chronic constipation – taking a prebiotic supplement can be helpful. However, intake should always be individually adjusted, as a sudden increase in fiber can lead to bloating or discomfort. A gradual introduction with stepwise adjustment has proven effective.

Fasting and the microbiome – a fresh start for your gut

Therapeutic fasting has been shown to have a regenerative effect on the microbiome. It helps to reduce pro-inflammatory bacteria while increasing the diversity of the gut flora. During the fasting phase, microbial colonization shifts towards a more balanced state, making the body more responsive to healthy nutrition – an ideal starting point for long-term change.

After fasting, it is especially important to provide the body with high-quality, gut-friendly foods. Refeeding should proceed gradually and be particularly rich in dietary fiber. Secondary plant compounds (phytochemicals), found in vegetables, herbs, and berries, deliver valuable impulses for rebuilding the microbiome. Fermented foods also make a decisive contribution to recolonization with beneficial bacteria.

To maintain these positive effects, a diverse, plant-based diet with at least 30 different plant foods per week is recommended. Animal products, sugar, and highly processed foods should continue to be reduced. Regular exercise and deliberate relaxation phases further support the stability of this new microbial balance.

Sources: 

Mesnage R et al., "Alterations in human gut microbiota following a fasting-mimicking diet", Nature Communications, 2021.

Prof. Dr. Andreas Michalsen – Ernährung – Meine Quintessenz. 2024. Insel Verlag Berlin.

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