Overview
The investigators aim to test the hypothesis that a microbiome-changing dietary intervention improves food decision-making and to determine the underlying microbiotal and metabolic mechanisms. To this end, 90 overweight/obese adults will be enrolled in a randomized controlled trial to test the effects of a pre-biotic dietary intervention (supplementary intake of soluble fibre) or a behavioural lifestyle intervention (weekly educational program) vs. control condititon (supplementary intake of isocaloric starch) over a period of 26 weeks. Before and after the intervention/control period, participants will undergo task-based functional and structural MRI and cognitive testing. The gut microbiota will be assessed using 16S rDNA next-generation sequencing (V3/V4 region) in stool samples. Diet, anthropometry and lifestyle will be monitored with questionnaires and metabolomics will be assayed in peripheral blood and stool (e.g. SCFA). Using a modulation of gut-brain communication through a prebiotic diet and lifestyle intervention, respectively, the investigators will be able to discover microbiota communities that play a key role for eating behaviour. Related mechanistic insights could help to develop novel preventive and therapeutic options to combat unhealthy weight gain in our obesogenic society.
Eligibility
Inclusion Criteria:
- BMI >= 25 kg/m2 or WHR >= 0.9/0.85 (m/d, f)
- no MRI contra-indication
- written informed consent
Exclusion Criteria:
- athletes
- occurrence of a clinically relevant psychiatric disease in the last 12 months, e.g. depression, substance abuse, eating disorders, schizophrenia
- any chronic inflammatory or malignant disease
- type 1 diabetes
- previous bariatric/gastric surgery
- pregnancy or breastfeeding woman