The study includes 3 visits. The first visit serves to check inclusion/exclusion criteria/complete questionnaire/give information about the study and receive consent. At visit 2 and 3 the included individuals will drink a placebo blend or a drink containing Lactobacillus rhamnosus GG (LGG®) and they will subsequently be biopsied from the upper intestine during endoscopy while under nurse administered propofol sedation (NAPS). There will be four weeks between visit 2 and 3.