Clinical trial NCT04522258: Effects of Dietary Fiber on Affective Processes
Official title: Effects of Dietary Fiber on Affective Processes
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Emotions
Stress
Fear
Lead sponsor: KU Leuven
Sponsor class: OTHER
First posted: 2020-08-21
Enrollment: 70
Sex: MALE
Minimum age (years): 20
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: The effects of dietary fiber on psychobiological processes are examined in a sample of healthy volunteers.

Detailed description: The study is an interventional triple-blind, placebo-controlled, parallel group design with 2 arms (placebo, dietary fiber). Healthy male participants adhere to their normal eating habits for the duration of the study (32 days). At the baseline study visit, measurements are taken in the lab, including biological samples and psychophysiological measurements. Participants then consume placebo or dietary fiber for 4 weeks and revisit the lab on day 32 for a second measurement of the outcomes of interest. Specifically, we investigate the effect of dietary fiber on affective processing, including stress sensitivity and fear-related processes (e.g. extinction learning). Volunteers also respond to questionnaires in relation to mood and GI symptoms, and provide biological samples (saliva, blood, faecal, and urine samples) for analysis of cortisol levels, circulating short chain fatty acids and serum BDNF, faecal SCFA and microbiota composition, and intestinal permeability, respectively.

Eligibility criteria: Inclusion Criteria:

* Male participants
* Age range 20-40 years
* BMI range 18.5-27
* Dutch or English as native-language

Exclusion Criteria:

* previous or current neurological, psychiatric, gastrointestinal or endocrine disorders, or other relevant medical history
* current or recent regular medication use
* previous or current substance/alcohol dependence or abuse (\> 2 units per day/14 units per week)
* one or more diagnoses based on the mini-international neuropsychiatric interview
* smoking
* night-shift work
* adherence to vegan or vegetarian diets
* use of pre- or probiotics within one month preceding the study
* use of antibiotics within 3 months preceding the study
* Habitual diet not exceeding consumption of 25 g of dietary fiber per day
* previous experience with one of the tasks used in the study

Primary outcomes:
measure: Stress sensitivity (cortisol)
timeFrame: through study completion, on average 1 year and 5 months
Secondary outcomes:
measure: Stress sensitivity (subjective)
timeFrame: through study completion, on average 1 year and 5 months
measure: Cortisol awakening response
timeFrame: through study completion, on average 1 year and 5 months
measure: Fear
timeFrame: through study completion, on average 1 year and 5 months
measure: Fear (subjective)
timeFrame: through study completion, on average 1 year and 5 months
measure: Positive and Negative Affect Schedule (PANAS)
timeFrame: through study completion, on average 1 year and 5 months
measure: Perceived Stress Scale (PSS)
timeFrame: through study completion, on average 1 year and 5 months
measure: Depression, anxiety, and stress scales (DASS-21)
timeFrame: through study completion, on average 1 year and 5 months
measure: Leiden Index of Depression Sensitivity-Revised (LEIDS-R)
timeFrame: through study completion, on average 1 year and 5 months
measure: Gastrointestinal symptom rating scale (GSRS)
timeFrame: through study completion, on average 1 year and 5 months
measure: Serum SCFA
timeFrame: through study completion, on average 1 year and 5 months
measure: Faecal SCFA
timeFrame: through study completion, on average 1 year and 5 months
measure: Intestinal permeability
timeFrame: through study completion, on average 1 year and 5 months
measure: Serum BDNF
timeFrame: 1 year and 5 months
Other outcomes:
Locations:
city: Leuven
country: Belgium
facility: UZ Leuven/Stresslab
state: I Am Not In The U.S. Or Canada
Study officials:
References: