The microbiome can influence its "host organism" in many ways and interact with it. The diversity of the colonic flora's composition seems to play a decisive role. Special bacterial species could have a protective effect on the development of metabolic diseases, while others could have a beneficial effect.
The intestinal flora is known to have a direct influence on human health. Its numerous physiological functions include the utilization of food and the influence on energy turnover. Conversely, changes in the intestinal flora can lead to the development of allergies and chronic inflammatory intestinal diseases. The altered bacterial spectrum of the intestinal flora can also influence the signalling pathways for hunger and satiety, nutrient utilization and energy balance and contribute to the development of obesity.
There are many indications that the composition of the gut microbiota influences the development of obesity and diabetes mellitus type 2. Since research into the microbiome has only been possible systematically for a few years thanks to modern analytical techniques, the mechanisms responsible for the connection between microbial and metabolic changes remain largely unclear.
According to studies, bariatric surgery can change the bacterial spectrum of the intestinal flora, which leads to an improvement in glucose regulation in diabetes mellitus type 2. It has been proven that the change in the intestinal flora after a gastric bypass surgery is not only a temporary effect of the procedure but also a permanent one. Study results not only prove the influence of the microbiome on body weight but also point to the mechanism of action of bariatric surgery by altering the intestinal microbiome.
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