The latest research on the microbiome and what it affects in your body.

Introduction to the microbiome

The human microbiome is a fascinating world of microscopic organisms that live in and on our bodies. These microorganisms, which colonize the skin, intestines, nose and other parts of the body, are not just co-inhabitants, but play a crucial role in our health. They contribute to vital functions, including the digestion of food and the absorption of nutrients that we would otherwise not be able to process. They also produce vitamins and anti-inflammatory substances.

Interestingly, the human body contains trillions of microorganisms that outnumber human cells by a ratio of 10 to 1. However, due to their small size, they only make up around 1 to 3 percent of the body mass, which corresponds to 1 to 3 kilos of bacteria in a 90 kilogram adult.

Research into the microbiome has shown that more than 10,000 microbial species colonize the human ecosystem. This contributes much more to human existence than our own genome. While the human genome contains around 22,000 genes, the microbiome provides an estimated 8 million unique genes.

This enormous diversity and density of microorganisms in the human body make the microbiome an integral part of our being and our health.

The diversity and uniqueness of the microbiome

The human microbiome is an incredibly diverse ecosystem that differs in its composition from person to person. This diversity is not only due to genetic factors, but is also strongly influenced by environmental factors, diet and lifestyle.

Influences on microbiome diversity

  • Age: The composition of the microbiome changes with age. Differences in the microbiome have been found in older people compared to younger adults, with the microbiome composition in older people clearly linked to frailty and diet.
  • Diet and lifestyle:Studies show that the microbiome can change depending on diet. For example, the Japanese population has developed unique microbial genes in the gut to digest these food components due to their dietary habits, which have historically included seaweed.
  • Lifestyle factors: Physical activity and dietary habits have a significant impact on the diversity of the microbiome. For example, it was found that physical activity and the consumption of fruit and vegetables correlate positively with microbiome diversity, while the consumption of sugary drinks has a negative influence.
  • Global diversity and cultural differences: The microbiome also varies geographically and culturally. For example, children in rural African villages have a different microbiome composition compared to European children. These differences are likely due to differences in diet, genetic background and environmental factors that vary between these populations.

Factors that put the microbiome at risk

The microbiome, especially that of the gut, is of crucial importance for human health. Certain factors can influence the composition of the microbiome and thus lead to various health problems.

There is a significant correlation between various lifestyle and clinical factors and the diversity of the microbiome. The factors that have a positive effect on microbiome diversity include

  • Physical activity
  • the consumption of fruit, vegetables and cruciferous vegetables
  • Omega-3 fatty acids.

A negative effect on microbiome diversity has

  • an increased BMI
  • High blood pressure
  • the consumption of sugary foods and drinks.

Effects of the microbiome on chronic diseases

Changes in the microbiome can contribute to autoimmune diseases. Asthma, especially in children, can be influenced by early environmental factors such as caesarean birth, antibiotic use, bottle feeding and air pollution. Certain types of bacteria (proteobacteria) are often found in larger quantities in asthma patients. Useful bacterial products, so-called short-chain fatty acids, can reduce inflammatory processes in the airways. The content of these substances, so-called postbiotics such as butyrate and propionate, in the stool at the age of one year is associated with a lower risk of atopic dermatitis and asthma in young children, for example.

Altered microbiome in irritable bowel syndrome (IBS)

IBS is characterized by abdominal pain, discomfort and altered bowel habits. Variations in the normal microbiome may play a role in the low-threshold gut inflammation associated with the syndrome. One study showed a clear difference between the microbiome of IBS patients and that of control subjects, with IBS characterized by an increase in certain bacterial species known as firmicutes.

How to recognize a disturbed microbiome

Disturbed gut microbiome

A disturbed microbiome, also known as dysbiosis, can be recognized by a number of signs and symptoms. These can vary depending on how severely the microbiome is affected and which other factors (such as diet, lifestyle and genetic predispositions) play a role.

1. digestive problems

One of the most common signs of a disturbed microbiome is digestive problems. These include symptoms such as flatulence, diarrhea, constipation and abdominal pain. These may indicate a change in the bacterial composition of the intestine.

2. changes in bowel habits

A change in the frequency, consistency or odor of the stool can also indicate dysbiosis. This can occur due to a change in bacterial activity and digestive processes in the intestine.

3. intolerances and allergies

An increase in food intolerances or allergic reactions can also be an indication of dysbiosis. The microbiome plays an essential role in immune regulation and its disruption can influence the body’s response to certain foods.

4. chronic fatigue

The microbiome influences nutrient absorption and energy production in the body. Chronic fatigue and a general feeling of exhaustion that is not alleviated by sleep or rest can therefore also indicate dysbiosis.

5. skin problems

The skin and the gut are closely related via the so-called gut-skin axis. Skin diseases such as acne, eczema or rosacea can also be associated with a disturbed microbiome.

6. mood swings and mental health

Recent research suggests that the microbiome plays a role in regulating mood and mental health. Depression, anxiety and mood swings can therefore also be linked to dysbiosis.

7. weight changes

Unexplained weight gain or loss without obvious changes in diet or exercise may indicate changes in the microbiome, as it plays a role in metabolism and body weight regulation.

8. immune function

Frequent infections or slow wound healing can also indicate a disturbed microbiome, as it plays an important role in supporting the immune system.

9. altered craving for certain foods

Changes in cravings for certain foods, especially sugar or highly processed foods, can also indicate dysbiosis.

Benefits of probiotics for the microbiome

According to the definition of the World Health Organization (WHO) and the Food and Agriculture Organization (FAO), probiotics are “living microorganisms which, when administered in sufficient quantities, have a health benefit for the host”.

Four criteria for qualification as a probiotic

For microorganisms to qualify as probiotics, they must fulfill four criteria:

  1. Sufficient characterization: The probiotic strains must be sufficiently characterized.
  2. Safety for the intended use: The logs must be safe for the intended use.
  3. Evidence from at least one positive human study: Efficacy must be demonstrated by at least one positive human clinical study conducted in accordance with generally accepted scientific standards.
  4. Viability in the product over the entire shelf life: The microorganisms must remain alive in the product in an effective dose over the entire shelf life.

So if you’re wondering whether certain foods such as yoghurt, kimchi or kombucha are probiotic, then according to this definition you can only answer in the negative. Because you don’t know which strains are contained in which quantities and unfortunately no studies have been carried out on this.

The role of probiotics in health

Probiotics interact with the gut microbiome and have a variety of positive effects on human health. They play an important role in modulating the gut microbiota and thereby influence various aspects of health, including immune function and the prevention of chronic diseases. Studies have shown that probiotics can help improve intestinal flora, strengthen the immune system, lower serum cholesterol, prevent cancer and treat diarrhea caused by irritable bowel syndrome. They also have antihypertensive effects and can improve the metabolism of lactose.

The benefits of probiotics

The benefits of probiotics include improved gut health, immune system support and potentially positive effects on various conditions beyond the gut, such as skin diseases and metabolic disorders. Their role in influencing health is extensive and continues to be researched to fully understand and exploit their potential applications in medicine.

Prebiotics and their importance

Prebiotics are a group of nutrients that are broken down by the intestinal microbiota. They play an important role in overall health and have an impact on well-being by nourishing the gut microbiota. In this way, prebiotics promote the growth of health-promoting bacteria in the gut, especially bifidobacteria, and can therefore help to maintain a healthy intestinal flora. The short-chain fatty acids produced by their breakdown are released into the bloodstream and have a positive effect not only on the gastrointestinal tract but also on other distant organs.

The most important groups of prebiotics include fructo-oligosaccharides and galacto-oligosaccharides. A good example of a natural source of fructo-oligosaccharides is inulin, which is obtained from blue agaves, for example. Inulin contains a high proportion of FOS and is often used in the manufacture of prebiotic food supplements, including the Ogaenics Love Your Gut Daily Biotic Complex.

Due to their health benefits and safety, as well as their production and storage advantages compared to probiotics, they are considered promising candidates for the promotion of human health, either as a replacement or in combination with probiotics.

Symbiotic relationship between prebiotics and probiotics

Prebiotics and probiotics interact in a symbiotic relationship. Prebiotics serve as food for the probiotics and thus support their survival and effectiveness in the intestine. This synergy improves intestinal health and can have a positive effect on other aspects of health. The combination of pre- and probiotics, known as synbiotics, can enhance the effectiveness of the individual components and thus improve the intestinal flora and overall health of the host.

The connection between gut microbiome and brain/skin

The gut-brain axis and the gut-skin axis are two important communication pathways that connect the gut with the brain and the skin respectively. Both axes play a decisive role in human health and well-being.

Gut-brain axis

This axis is a complex bidirectional communication network that connects the gut and the brain. It comprises neuronal, immunological and endocrine communication pathways between the gastrointestinal tract and the central nervous system (CNS). Disturbances in this axis can be observed in a variety of clinical pictures, including neurodegenerative disorders and mental illnesses. The gut microbiota plays a crucial role in this axis by influencing the production of neurotransmitters such as dopamine, serotonin and gamma-aminobutyric acid (GABA). These neurotransmitters are essential for neuronal communication and have far-reaching effects on the brain and behavior.

Gut-skin axis

Similar to the gut-brain axis, the gut-skin axis establishes a connection between the gut and the skin. The gut microbiota influences skin health by regulating the immune response and inflammatory processes. Dysbiosis in the gut can lead to a disturbed skin barrier and skin inflammation. These interactions are particularly important for skin diseases such as psoriasis. Clinical cases and animal models show that the gut microbiota has an influence on the skin via the production of neurotransmitters. Here too, the manipulation of neurotransmitters by bacteria can have an effect on the physiology of the host.

Research on these axes offers new insights into the complex interaction between the microbiome, the brain and the skin. These findings could lead to new therapeutic approaches for a variety of diseases in the future. It becomes clear that the health of the gut plays a central role in the health of the whole body and that a balanced gut flora could be important for the prevention and treatment of brain and skin diseases.

Effects of stress on the microbiome

The link between stress and the microbiome is a complex field that is increasingly being researched. Stress, both psychological and physiological, can have significant effects on the microbiome, especially the gut microbiome.

The gut-brain axis plays an important role in the relationship between stress and the microbiome. Various studies show that stress factors alter the microbiome and thereby influence communication along the gut-brain axis, which can lead to various psychological and neurological disorders.

Due to the close connection between stress, the microbiome and health, the use of probiotics to alleviate stress and anxiety symptoms is also being researched. The consumption of probiotics can potentially modulate the gut microbiome and thereby support stress management and anxiety reduction. This suggests that probiotics may have positive effects on stress management.

Probiotics for intestinal problems: Case studies

The use of probiotics for intestinal problems, especially irritable bowel syndrome (IBS), is a topic that is attracting increasing attention in medical research. Various studies have shown that probiotics can have potentially positive effects on the symptoms of irritable bowel syndrome.

Probiotics in irritable bowel syndrome (IBS): A comprehensive systematic review published on PubMed examined the effects of probiotics on the symptoms of IBS patients. This review included 11 randomized controlled trials, of which seven (63.6%) reported that probiotic supplementation significantly improved symptoms in IBS patients compared to placebo. Interestingly, the positive effects were more pronounced in the studies that used multi-strain probiotics for a period of eight weeks or longer, suggesting that long-term use of multi-strain probiotics has the potential to improve symptoms of IBS.

Probiotics in inflammatory bowel disease (IBD): Another systematic review that focused on the use of probiotics in inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis found no clear evidence for the efficacy of probiotics in Crohn’s disease. However, some studies have shown that the combination of standard treatments with probiotics could lead to remission in active ulcerative colitis.

Probiotics for the prevention of antibiotic-associated diarrhea (AAD): The efficacy of probiotics for the prevention of AAD is strain-specific. Studies have shown that certain probiotic strains such as Saccharomyces boulardii CNCM I-745 and Lactobacillus rhamnosus GG can effectively contribute to the prevention of AAD.

Probiotics and insulin resistance: A systematic review has shown that probiotics may have positive effects on insulin resistance. Significant improvements in measures of insulin resistance have been seen in animal studies, although results in human clinical trials have been heterogeneous.


In conclusion, taking care of your microbiome is an essential aspect of optimizing your health. An approach such as the Ogaenics Love Your Gut Daily Biotic Complex, which combines probiotics and prebiotics, can help maintain or restore the balance of the microbiome.

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