Healthy Adult
Conditions
Keywords
Gastrointestinal, Cognition, Probiotics, Healthy adults, Alcohol
Brief summary
The aim of this clinical trial is to investigate whether taking probiotics can improve thinking ability and digestive symptoms in healthy adults, and whether these effects depend on how often someone drinks alcohol. The study will also explore whether probiotics affect mental health, alcohol cravings, and drinking and eating behaviours. The main questions it aims to answer are: * Do probiotics improve everyday thinking, attention, and memory? * Do probiotics reduce digestion issues or discomfort? * Does how often someone drinks alcohol affect how much they benefit from probiotics? * Do probiotics modulate alcohol cravings? * Do probiotics improve mood, stress, and anxiety levels? * Do probiotics influence drinking behaviour? * Do probiotics influence eating behaviour? Researchers will compare a probiotic supplement to a placebo (a look-alike product with no active ingredients) to see whether probiotics have real effects. Participants will be randomly assigned to one of these groups, and neither the participants nor the researchers will know who is receiving which treatment during the study. Participants will: * Take either a probiotic supplement or a placebo every day for 8 weeks * Complete online questionnaires about their mood, thinking, eating and drinking behaviours, and digestive health at the start and end of the study * Provide basic lifestyle and demographic information This study aims to better understand whether probiotics could be a simple and low-cost way to support cognitive function, digestive health, and other wellbeing outcomes in generally healthy adults - and whether these benefits vary depending on how often someone drinks alcohol.
Interventions
The participant will be randomly assigned to receive the probiotic, containing the active ingredient and live bacteria
The participant will be randomly assigned to receive the placebo, containing no active ingredient/live bacteria
Sponsors
Study design
Eligibility
Exclusion criteria
* Participants under 18 years of age * Regular use of probiotics or prebiotics (in supplements or foods) within the past 4 weeks * Antibiotic use within the past 4 weeks * Chronic gastrointestinal disorders (e.g. Irritable Bowel Syndrome, Crohn's disease, etc) * Major psychiatric conditions diagnosed (e.g., bipolar disorder, schizophrenia, etc) * Current pregnancy or breastfeeding
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 85 non-clinical participants assessed for Everyday Cognitive Failures by Cognitive Failures Questionnaire 2.0 | From enrollment to the end of the treatment at 8 weeks | Everyday cognitive functioning will be assessed using the Cognitive Failures Questionnaire 2.0 (CFQ 2.0), a 15-item self-report questionnaire measuring the frequency of cognitive lapses in daily life (e.g., memory, attention, and action errors). Each item is rated on a 5-point scale. Total scores are calculated by summing all item responses, yielding a score ranging from 0 to 60. Performance will be measured as the total CFQ 2.0 score (range 0-60), with higher scores indicating greater frequency of cognitive failures. |
| 85 non-clinical participants assessed for Gastrointestinal Symptoms by Gastrointestinal Symptom Rating Scale | From enrollment to the end of the treatment at 8 weeks | Gastrointestinal symptoms will be assessed using the Gastrointestinal Symptom Rating Scale (GSRS), a 15-item self-report questionnaire evaluating the severity of common gastrointestinal symptoms. Each item is rated on a 7-point Likert scale, with higher scores indicating more severe symptoms. Total scores are calculated by summing all item responses, yielding a score ranging from 15 to 105. Performance will be measured as the total GSRS score (range 15-105), with higher scores indicating greater gastrointestinal symptom severity. Domain scores may also be calculated by averaging relevant items to assess specific symptom clusters. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 85 non-clinical participants assessed for Drinking Behaviour by Loughborough Alcohol Drinking Questionnaire | From enrollment to the end of the treatment at 8 weeks | Drinking behaviour will be assessed using the Loughborough Alcohol Drinking Questionnaire (LoAD-Q), a 33-item self-report questionnaire measuring three dimensions: emotional drinking, external drinking, and restrained drinking. Each item is rated on a 5-point Likert scale (1 = never to 5 = very often). Subscale scores are calculated by summing item responses within each dimension. The emotional drinking subscale (13 items) has a score range of 13 to 65, the external drinking subscale (10 items) ranges from 10 to 50, and the restrained drinking subscale (10 items) ranges from 10 to 50. Performance will be measured as subscale total scores, with higher scores indicating greater levels of emotional, external, and restrained drinking behaviour, respectively. |
| 85 non-clinical participants assessed for Depression, Anxiety, and Stress by Depression Anxiety Stress Scales-12 | From enrollment to the end of the treatment at 8 weeks | Mental health symptoms will be assessed using the Depression Anxiety Stress Scales-12 (DASS-12), a 12-item self-report questionnaire measuring symptoms of depression, anxiety, and stress. Each item is rated on a 4-point Likert scale (0-3), yielding a total score ranging from 0 to 36. Performance will be measured as the total DASS-12 score (range 0-36), with higher scores indicating greater psychological distress. |
| 85 non-clinical participants assessed for Alcohol Craving by Penn Alcohol Craving Scale | From enrollment to the end of the treatment at 8 weeks | Alcohol craving will be assessed using the Penn Alcohol Craving Scale (PACS), a 5-item self-report questionnaire measuring frequency, intensity, and duration of alcohol cravings over the past week. Each item is rated on a scale from 0 to 6, yielding a total score ranging from 0 to 30. Performance will be measured as the total PACS score (range 0-30), with higher scores indicating greater alcohol craving severity. |
Countries
United Kingdom