Effects of Dietary Fiber on Affective Processes

Stress Clinical Trial

Official title:

Effects of Dietary Fiber on Affective Processes

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04522258
• Other study ID #: S62344
• Status: Completed
• Phase: N/A
• Start date: May 2, 2019
• Est. completion date: November 8, 2020

Study information

• Verified date: January 2021
• Source: KU Leuven
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

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

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 70
• Est. completion date: November 8, 2020
• Est. primary completion date: November 8, 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Male
• Age group: 20 Years to 40 Years

Eligibility

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

Related Conditions & MeSH terms

• Emotions
• Fear
• Stress

Intervention

Dietary Supplement:
• Dietary fiber
Fermentable cereal bran
• Placebo
Refined cereal flour

Locations

Country	Name	City	State
Belgium	UZ Leuven/Stresslab	Leuven	I Am Not In The U.S. Or Canada

Sponsors (1)

Lead Sponsor	Collaborator
KU Leuven

Country where clinical trial is conducted

Belgium, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Stress sensitivity (cortisol)	Induction of cognitive, physical, and social stress using Maastricht Acute Stress Test. Stress hormone cortisol is quantified by gathering multiple saliva samples throughout the stress induction and recovery during both pre-intervention and post-intervention visit.	through study completion, on average 1 year and 5 months
Secondary	Stress sensitivity (subjective)	Induction of cognitive, physical, and social stress using Maastricht Acute Stress Test. Participant rate how much stress, discomfort, and pain they feel on a 10-cm visual analogue scale, with higher values indicating greater stress, discomfort, and pain. This is done prior to stress induction, in the middle, and at the end at both pre- and post-intervention visits.	through study completion, on average 1 year and 5 months
Secondary	Cortisol awakening response	Measuring chronic stress by quantifying cortisol in morning samples (5 samples taken form the moment of waking every 15 minutes for 1 hour) on the morning of the pre- and post-intervention visits.	through study completion, on average 1 year and 5 months
Secondary	Fear	Exploring fear-related processes (conditioning, extinction, recall, and renewal) by means of a computerised task. Fear response is measured using skin conductance, and a skin conductance response is calculated.	through study completion, on average 1 year and 5 months
Secondary	Fear (subjective)	Exploring fear-related processes (conditioning, extinction, recall, and renewal) by means of a computerised task. Fear response is measured subjectively by asking participants to indicate their expectancy of an aversive stimulus.	through study completion, on average 1 year and 5 months
Secondary	Positive and Negative Affect Schedule (PANAS)	Assessing ratings on the subscales of PANAS, positive and negative affect. PA subscale scores range between 10-50, with higher scores indicating better outcome.; NA subscale scores range between 10-50, with higher scores indicating worse outcome.	through study completion, on average 1 year and 5 months
Secondary	Perceived Stress Scale (PSS)	Assessing ratings on PSS PSS scores range between 0-40 with higher scores indicating worse outcome.	through study completion, on average 1 year and 5 months
Secondary	Depression, anxiety, and stress scales (DASS-21)	Assessing ratings on the subscales of DASS-21, depression, anxiety, and stress subscales.; Higher scores on these subscales indicates a worse outcome.; Normal (depression: 0 - 4; anxiety: 0 - 3; stress: 0 - 7), Mild (depression: 5 - 6; axiety: 4 - 5; stress: 8 - 9), Moderate (depression: 7 - 10; anxiety: 6 - 7; stress: 10 - 12), Severe (depression: 11 - 13; anxiety: 8 - 9; stress: 13 - 16), Extremely Severe (depression: 14 +; anxiety: 10 +; stress: 17 +).	through study completion, on average 1 year and 5 months
Secondary	Leiden Index of Depression Sensitivity-Revised (LEIDS-R)	Assessing ratings on the subscales of LEIDS-R and its total score. This is a self-report on cognitive reactivity comprised of 34 items with six subscales. Hopelessness/suicidality; Acceptance/Coping; Aggression; Control/Perfectionism; Risk Aversion; Rumination.	through study completion, on average 1 year and 5 months
Secondary	Gastrointestinal symptom rating scale (GSRS)	Assessing ratings on the subscales of GSRS and its total score. It has 5 subscales (Reflux, Diarrhea, Constipation, Abdominal Pain, and Indigestion Syndrome). Subscale scores range from 1 to 7 and higher scores indicates a worse outcome.	through study completion, on average 1 year and 5 months
Secondary	Serum SCFA	Quantification of serum SCFA (µM) at pre- and post-intervention	through study completion, on average 1 year and 5 months
Secondary	Faecal SCFA	Quantification of faecal SCFA in samples provided at pre- and post-intervention	through study completion, on average 1 year and 5 months
Secondary	Intestinal permeability	Conducting a lactulose and mannitol test before and after the intervention	through study completion, on average 1 year and 5 months
Secondary	Serum BDNF	Quantification of fasting serum BDNF levels (µg/mL)	1 year and 5 months