Clinical trial NCT03829189: High-fiber Diet on the Body and the Brain
Official title: Interventional Study Comparing the Effect of a High-fiber Supplement Versus Placebo on the Body and the Brain
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Diet Modification
Overweight
Keywords: microbiome
food wanting
memory
fiber
Lead sponsor: Max Planck Institute for Human Cognitive and Brain Sciences
Sponsor class: OTHER
First posted: 2019-02-04
Enrollment: 61
Sex: ALL
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Arm 1: inulin; minimum of 14 days wash-out; 14 days placebo Arm 2: 14 days placebo; minimum of 14 days wash-out; 14 days placebo
Primary purpose: BASIC_SCIENCE

Brief summary: The central research question aims to understand what drives individuals to make and maintain a vegan / vegetarian dietary decision, to investigate whether there are possible predictors that might influence such a decision and whether personality differences already exist or can only be measured after the change in diet. The investigators will examine the effects of a high-fiber diet on food wanting on a neural and on a behavioral level. The microbiome is suggested to mediate the expected changes in food wanting.


Eligibility criteria: Inclusion Criteria:

* body-mass-index 25-30kg/m\^2
* females on contraception only

Exclusion Criteria:

* current neurological or psychiatric illness
* daily consumption of more than 50 g of alcohol, more than 10 cigarettes or more than 6 cups of coffee
* use of antidepressants or other centrally acting drugs
* type 2 diabetes mellitus or other serious metabolic disorders
* MRI contraindication (e.g. cardiac pacemaker, drug pump, shunts)
* major untreated medical condition, including gastrointestinal organs, lungs, heart, cardiovascular system, liver and kidney)
* diet-related restrictions (food allergies, food intolerances, known nutrient deficiencies or a recent history of dieting or restrictive eating behaviour, including vegan, vegetarian diet)
* current pregnancy or lactation

Primary outcomes:
measure: fMRI BOLD activity during food wanting
timeFrame: 14 days
measure: microbial alpha and beta diversity
timeFrame: 14 days
Secondary outcomes:
measure: fMRI BOLD activity memory performance
timeFrame: 14 days
measure: positive and negative affect
timeFrame: 14 days
measure: mood
timeFrame: 14 days
measure: emotional health
timeFrame: 14 days
measure: well-being
timeFrame: 14 days
measure: satiety
timeFrame: 14 days
measure: serum lipid metabolism markers
timeFrame: 14 days
measure: serum glucose metabolism markers
timeFrame: 14 days
measure: serum glucose metabolism markers
timeFrame: 14 days
measure: serum inflammatory markers
timeFrame: 14 days
measure: hunger hormones
timeFrame: 14 days
measure: serum microbial metabolic markers
timeFrame: 14 days
measure: personality traits
timeFrame: 14 days
measure: gastrointestinal health
timeFrame: 14 days
Other outcomes:
Locations:
city: Leipzig
country: Germany
facility: Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences
state: Saxonia
Study officials:
References:
citation: Medawar E, Haange SB, Rolle-Kampczyk U, Engelmann B, Dietrich A, Thieleking R, Wiegank C, Fries C, Horstmann A, Villringer A, von Bergen M, Fenske W, Veronica Witte A. Gut microbiota link dietary fiber intake and short-chain fatty acid metabolism with eating behavior. Transl Psychiatry. 2021 Oct 1;11(1):500. doi: 10.1038/s41398-021-01620-3.