In the podcast "Das Gastroenterologische Quartett" Prof. Dirk Haller talks about microbiome analysis in medical consultation, healthy and morbid microbiome, interactions with our brain and the state-of-the-art of microbiome functionality. PD Dr. med. Irina Blumenstein, Prof. Dr. med. Axel Dignaß and Prof. Dr. med. Stefan Schreiber question him on the role of the microbiome in inflammatory bowel disease, the effectiveness of probiotics and fecal transplantation.