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.
BMI >= 25 kg/m2 or WHR >= 0.9/0.85 (m/d, f)
no MRI contra-indication
written informed consent
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
Parallel
Inulin
Dietary supplement28g/day delivered in 2 sachets throughout the day with main meals
Lifestyle intervention
Behavioralweekly educational sessions to improve individual's eating behaviour
Placebo
Dietary supplementequicaloric maltodextrin delivered in 2 sachets throughout the day with main meals
blood-oxygenation-level-dependent (BOLD) activity during food wanting
BOLD-acitvity will be measured using event-related echo-planar T2\*-weighted magnetic resonance imaging (MRI) during food wanting task according to previously described procedures (details of preprocessing at: https://osf.io/ynkxw). Onsets of food and art stimuli presentation will be modelled as separate regressors convolving delta functions with a canonical hemodynamic response function. Wanting rating scores (on an 8-point likert scale) per stimulus will be added as covariates. In a parallel model, kcal of food stimuli will be added multiplied with wanting scores to model high caloric food wanting interaction. At the group level, we will assess the contrasts food \> art and wanting modulation.
microbial alpha and beta diversity
Changes in alpha and beta diversity assessed using 16S rRNA sequencing of stool samples
fMRI BOLD activity memory performance
BOLD-acitvity will be measured using event-related echo-planar T2\*-weighted magnetic resonance imaging (MRI) during food wanting and food memory recognition tasks according to previously described procedures (details of preprocessing at: https://osf.io/ynkxw). Onsets of food and art stimuli presentation in encoding and recognition will be modelled as separate regressors convolving delta functions with a canonical hemodynamic response function. Correctly remembered and correctly rejected, as well as misses and false alarms will be modeled separately. In parallel models, similar and new items als well as wanting rating scores (on an 8-point likert scale) per stimulus and kcal of food stimuli multiplied with wanting scores will be added as covariates. At the group level, we will assess the contrasts correct \> false and wanting modulation.
satiety
self-reported hunger feeling on a 8-point score from minimum 0 (not at all) to maximum 8 (very much).
ghrelin
ghrelin pg/ml in blood
Click on the lead sponsor to view all of their trials.
Max Planck Institute for Human Cognitive and Brain Sciences
Lead sponsor
Universitätsklinikum Leipzig
Collaborator
DFG - Deutsche Forschungs Gemeinschaft (German Research Foundation)
Collaborator
Helmholtz-Zentrum für Umweltforschung - UFZ
Collaborator
