The intestinal flora is an important component of our body. According to a study from 2017, the ratio of microorganisms in the body compared to human cells was newly estimated at about 1:1. Our microbiota performs many tasks to keep us healthy: for example, it protects the intestinal barrier from the colonization of pathogenic bacteria, produces essential vitamins, and plays a role in the development and maturation of the immune system.
As long as the child is in the womb, the infant intestine is sterile. The birth marks the beginning of a large-scale bacterial colonization, which will play a role in the development of the child and will shape its immune system. The development of the child’s microbiota is very dynamic and reaches a stable composition, similar to that of an adult, at the age of 2-3 years. Scientific studies show that the first 1’000 days, from fertilization to the end of the second year of life, are fundamental for the development and later well-being of a child. During this time, environmental aspects such as nutrition, hygiene and the place of residence have a formative influence on the intestinal flora and the immune system of the growing child.
As this is a topic that is still mechanistically poorly investigated, our BeBiCo study aims to better understand the maturation of the infant microbiota and the environmental factors (maternal and infant nutrition, mode of birth, home environment, pathogens) that influence this process during the first 10 years of life, with a main focus on the first two years of life.
In a first analysis, we analyzed the microbiota of children who have already reached the first year of life (Figure 2). Each column shows the average microbiota composition at one of the different time points of sample collection. The different colors code for bacteria from a different phylum. All colors together add up to 100%. We can clearly see that the gut flora undergoes a change over the first year of life. While an adult intestinal flora consists largely of bacteria of the
Bacteroidetes (light green) and Firmicutes (pink) species, the infant intestinal flora contains many bacteria that can be assigned to the Actinobacteria (purple) and the Deferribacteres (darker green).. A comprehensive analysis of the stool samples is pending.