The makeup of the microbiome or flora in the gut is crucial for our overall physical health. Several studies have demonstrated links between bacterial diversity in the gut and, e.g., metabolic or inflammatory skin diseases. Hence, in order to improve physical well-being, scientists and medical practitioners have repeatedly made efforts to accomplish lasting changes to a patient’s gut flora. Often, however, they have had to realise that external factors such as diets or specific probiotic treatments only have a limited impact.
Recently, an international team of researchers has shown that, at least in mice, there is a short time window immediately after birth during which the microbiome receives its individual composition. But what determines this composition? The journal LABO quotes the study published in the journal Nature, according to which a molecular factor was identified, “which is only active in mice until 21 days after birth, and during this time influences which bacteria colonise the intestines.”
Even if the results cannot be related 100 % to the situation in humans, “but for the mouse this is about the time when the transition occurs from mother’s milk to solid food. In humans this would equate to approximately six months,“ LABO quotes Dr. Felix Sommer of the Institute of Clinical Molecular Biology at Kiel University, the study’s co-author. The magazine also has Professor Philipp Rosenstiel of the Cluster of Excellence „Inflammation at Interfaces“ saying that „the study shows that there is a critical phase very early in life, in which we need to see certain bacteria, so that thereafter a diverse and well-functioning intestinal microbiome is present.“
On the other hand, however, this would also mean that, in particular during the first months after they are born and possibly during the transition from mother’s milk to solid food, it is important for children to have a healthy bacterial diversity enter their bodies and hence their gut, e.g. by exploring the environment with their mouth, so that a stable, diverse and functional flora can form in the gut. Naturally, children should still be protected from pathogens, yet well-meant, excessive hygiene would do them a disservice.