[The microbiome and the first 1,000 days of life].

A healthy human being lives in symbiosis with his microbes or microbiome. The first 1,000 days of life are crucial for developing a healthy and diverse microbiome. The development of a healthy microbiome begins as early as in the womb, where the training of the fetal immune cells begins. Next, the child s microbiome is influenced by the method of delivery during the birthing process. The largest and most important phase is the postnatal period. In this last phase, the child s environment, the behaviour and lifestyle of its caregivers, and the child itself are the main determinants of developing and maintaining a healthy microbiome.