Our intestinal bacteria ferment fats, carbohydrates and proteins; they also stimulate intestinal peristalsis and regulate stool volume and colonic transit time. They break down soluble fiber into short-chain fatty acids (short chain fatty acids, SCFAs) and form acetic acid (acetate), butyric acid (butyrate) and propionic acid (propionate) as the main sources of energy for the cells of the intestinal wall (colonocytes).
They produce vitamins B and K, essential amino acids, neuroactive messenger substances and bioactive lipids. There is a constant exchange of substances between the bacterial microfilm of the intestinal wall (mucus layer) and the bloodstream. An incorrect colonization with harmful bacteria can lead to the passage of harmful substances into the bloodstream (permeable bowel syndrome).
Intestinal bacteria have a significant effect on our immune system. They stimulate and train it:
- the intestine-associated immune system (gut associated lymphoid tissue, GALT)
- Defensins (antimicrobial amino acid chains)
- pathogen-associated patterns (pathogen associated molecular patterns, PAMPs)
Some species secrete antimicrobial peptides (bacteriocides) to maintain the specific microbiota family and thus maintain the balance between pathogenic and beneficial germs (resilience).
Bacteria stimulate the formation of regulatory T cells, which have an anti-inflammatory effect in the immune response. There are also species that activate or inhibit orally administered drugs by means of specific metabolization pathways and signal transduction chains. The success of therapy may depend on this.
The diversity of the bacterial spectrum with its numerous metabolic pathways and modes of function determines the supply of the right nutrients, regulates the immune response and interacts with all other organs of the body - thus shaping human health.
Test repetitions: An intestinal microbiome analysis is a static recording of a dynamic process, which is why further examinations are recommended after a therapy or lifestyle change.
