An interventional study of Probiotic and Placebo in Healthy Adult Participants, sponsored by Mental Health Centre Copenhagen, Bispebjerg and Frederiksberg Hospital. Not yet recruiting. Open to participants aged 18 Years to 30 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-07.
Sponsored by Mental Health Centre Copenhagen, Bispebjerg and Frederiksberg Hospital · Not applicable, Interventional, and Basic science
This randomized, double-blind, placebo-controlled pilot study will evaluate the effects of four weeks of supplementation with a probiotic on mental health in healthy adults aged 18-30 years. Participants will be randomized to receive either probiotic or placebo and will complete study assessments at baseline and end of intervention, and will complete a range of behavioral, physiological, and questionnaire-based assessments before and after the intervention. The primary objective is to assess the effect on emotional reactivity measured in a virtual reality scenario at the end of the intervention. This exploratory study is intended to generate data to inform future clinical research.
2,193 studies on the registry are indexed under Psychological Well-Being; 728 are open to participants now.
This study's planned enrollment of 60 is below the median of 110 across 1,796 interventional studies indexed under Psychological Well-Being.
Browse Psychological Well-Being studies →Mental Health Centre Copenhagen, Bispebjerg and Frederiksberg Hospital is the lead sponsor of 19 studies on the registry; 7 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Daily oral supplementation of probiotic for 4 weeks
Dietary Supplement: Probiotic
Daily oral supplementation of placebo for 4 weeks
Dietary Supplement: Placebo
Participants will be instructed to take one capsule once daily in the morning with a meal and water.
Participants will be instructed to take one capsule once daily in the morning with a meal and water.
VIRDIS: Rating of unpleasantness in a virtual reality social scenario
Participants complete a virtual reality-based assessment (VIRDIS) and rate their level of unpleasantness following exposure to a predefined social scenario. Unpleasantness is assessed on a 5-point scale ranging from 1 (not at all unpleasant) to 5 (very unpleasant).
Time frame: This outcome is assessed only at treatment completion (at week 4).
VIRDIS: a composite score of ratings of unpleasantness across all virtual reality scenarios
This outcome comprises the mean unpleasantness score across all VR scenarios in the VIRDIS test on a scale ranging from 1 (not at all unpleasant) to 5 (very unpleasant).
Time frame: This outcome is assessed only at treatment completion (at week 4)
VIRDIS: heart rate
Heart rate is measured during the VIRDIS assessment (using a wearable physiological monitoring device). Heart rate (pulse) is reported in beats per minute (bpm). Higher scores indicating higher heart rate.
Time frame: This outcome is assessed only at treatment completion (at week 4).
Short Form 36 - Energy/Vitality subscale
The SF-36 questionnaire will be administered in its entirety. The Energy/Vitality subscale (items 23, 27, 29, and 31) is designated as a secondary outcome measure.
Time frame: Change from baseline to treatment completion (at week 4)
VIRDIS: heart rate variability
Heart rate variability is measured during the VIRDIS assessment (using a wearable physiological monitoring device). HRV is derived from the variation in time between consecutive heartbeats (interbeat intervals).
Time frame: This outcome is assessed only at treatment completion (at week 4).
VIRDIS: galvanic skin response
Skin conductance (electrodermal activity) measured during the VIRDIS assessment. Outcomes include tonic and phasic skin conductance measures reported in microsiemens (µS).
Time frame: This outcome is assessed only at treatment completion (at week 4).
VIRDIS: pupil dilation
Pupil dilation is measured during the VIRDIS assessment using integrated eye-tracking technology. The outcome is reported as change in pupil diameter (mm).
Time frame: This outcome is assessed only at treatment completion (at week 4).
VIRDIS: gaze velocity
Eye-tracking technology integrated into the VIRDIS assessment records gaze behavior during the virtual reality scenarios. This outcome is reported as the mean gaze velocity (°/s), i.e., average angular velocity of eye movements recorded throughout the virtual reality assessment. Unit of measure: degrees/second (°/s).
Time frame: This outcome is assessed only at treatment completion (at week 4).
VIRDIS: saccade amplitude
Eye-tracking technology integrated into the VIRDIS assessment records mean saccade amplitude in the virtual reality scenarios measures as the average angular distance of saccadic eye movements (i.e., rapid eye movement between two points of focus). Unit of measure: degrees
Time frame: This outcome is assessed only at treatment completion (at week 4).
Short Form 36
The SF-36 is a self-administered quality of life questionnaire comprising 36-items measuring eight health domains: physical functioning (10 items), role limitation due to physical health problems (4 items), bodily pain (2 items), general health perceptions (5 items), vitality (4 items), social functioning (2 items), role limitations due to emotional problems (3 items), and general mental health (5 items). These outcomes will be grouped as physical component summary and mental component summary. The norm data is 0-100, the health-related quality of life increases as the scores increase. The average score is 50.
Time frame: Change from baseline to treatment completion (at week 4).
European Quality of Life - 5 Dimensions (EQ-5D)
Questionnaire on quality of life. Part A score range: 5-15. Part B: VAS scale: 0-100.
Time frame: Change from baseline to treatment completion (at week 4).
Pittsburgh Sleep Quality Index (PSQI)
Questionnaire assessing subjective sleep quality. Outcomes include the global PSQI score (range 0-21) and the seven component scores: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleep medication, and daytime dysfunction. Higher scores indicate poorer sleep quality.
Time frame: Change from baseline to treatment completion (at week 4)
Perceived Stress Scale (PSS)
Questionnaire on perceived stress. Score range 0-40.
Time frame: Change from baseline to treatment completion (at week 4)
Major Depression Inventory (MDI)
Questionnaire on depressive symptoms. Score range 0-72.
Time frame: Change from baseline to treatment completion (at week 4)
Cognitive Complaints in Bipolar Disorder Rating Assessment (COBRA)
Questionnaire on cognitive difficulties. Score range 0-48.
Time frame: Change from baseline to treatment completion (at week 4)
State-Trait Anxiety Inventory Questionnaire (STAI)
Questionnaire on anxiety. Score range 20-80.
Time frame: Change from baseline to treatment completion (at week 4).
Attentional Control Scale (ACS)
Questionnaire on attentional control. Score range 12-48.
Time frame: Change from baseline to treatment completion (at week 4)
Emotion Regulation Questionnaire (ERQ)
Questionnaire on emotion regulation. Score range 7-49.
Time frame: Change from baseline to treatment completion (at week 4)
Difficulties in Emotion Regulation Scale (DERS)
Questionnaire on emotion regulation. Score range 0-144.
Time frame: Change from baseline to treatment completion (at week 4)
Cognitive Emotion Regulation Questionnaire (CERQ)
Questionnaire on emotion regulation. Score range 0-72.
Time frame: Change from baseline to treatment completion (at week 4)
CANTAB: Paired Associates Learning (PAL)
Computerized test assessing visuospatial memory and new learning. The main outcome is the total number of errors (incorrect boxes selected) made across all stages, adjusted to account for stages not completed.
Time frame: This outcome is assessed only at treatment completion (at week 4)
CANTAB Rapid Visual Processing
A computerised neuropsychological test assessing sustained attention. The outcome measure is A-prime (A'), which measures target sensitivity (sustained attention). score range 0-1.
Time frame: This outcome is assessed only at treatment completion (at week 4).
CANTAB Spatial Working Memory task
A computerised neuropsychological test assessing spatial working memory. The main outcome is the number of times a participant revisits a box that has already been opened and found to be empty in a specific trial.
Time frame: This outcome is assessed only at treatment completion (at week 4).
Emotional categorisation task (EMO-CAT)
A computerized emotional processing task in which participants categorize positive and negative personality trait words according to whether they would like or dislike being described by each characteristic. Following the categorization task, participants are asked to recall as many words as possible.
Time frame: This outcome is assessed only at treatment completion (at week 4).
Valence Bias Task
Computerized emotional processing task assessing valence bias during evaluation of emotional facial expressions. The primary outcome is valence bias, defined as the percentage of ambiguous surprised faces rated as "bad."
Time frame: This outcome is assessed only at treatment completion (at week 4).
Social Scenarios Test
Computerized task assessing emotional reactivity and emotion regulation in response to positive, negative, and neutral social scenarios. The outcome measure is emotional response rated on a 100-point visual analogue scale (VAS) of discomfort or pleasure.
Time frame: This outcome is assessed only at treatment completion (at week 4).
Facial Emotion Recognition Test (FERT)
Computerized task assessing recognition of emotional facial expressions. The outcome measure is emotion recognition accuracy, defined as the proportion of correctly identified emotional expressions.
Time frame: This outcome is assessed only at treatment completion (at week 4)..
No study locations are listed for this record.
Plan to share: Yes — Although full open access is restricted due to General Data Protection Regulation, anonymised participant data may be shared on resonable request to researchers who provide a methodologically sound proposal, beginning 6 months after publication. Study protocols and statistical analysis plans will also be available. Proposals should be directed to Kamilla.woznica.miskowiak@regionh.dk. to gain access and data requestors will need to sign a data access agreement.
Supporting information: Study protocol, Statistical analysis plan
Time frame: Six months after publication
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Probiotic
Mental Health Centre Copenhagen, Bispebjerg and Frederiksberg Hospital