After years of working as a researcher and seeing patients, the "inconsistency" of seeing a lot of research remain "within laboratories" led Andreu Prados to dedicate himself to "communicating" science, to "translate it" for both patients and students and health professionals. Few voices are more didactic than his to talk about one of the most forgotten parts of our body: the vagus nerve. For some time now, videos have been proliferating on social media explaining that it is altered and that there are tricks to retrain it. But what is true in all these publications? Does the vagus nerve really have such a direct impact on our well-being? Prados, who specializes in digestive disorders, explains that knowing it is key to understanding how one of the great ills of the 21st century works from within: stress.