Gastrointestinal diagnostics using the GI EFFECT Microbial Ecology Profile (Genova Diagnostics). The study in detail assesses the intestinal microbiota, the integrity of the intestinal mucosa (assessment of zonulin levels), the need for gastrointestinal support with pro and prebiotics, potential parasitic infections (3-day study) and the presence of bacteria disrupting the normal microflora. It informs about disorders in the intestinal microbiota (intestinal dysbiosis).