An interventional study of Fermented Foods and High Fibre in Healthy, sponsored by University College Cork. Recruiting at 1 site in Ireland. Open to participants aged 18 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-07-16.
Sponsored by University College Cork · Not applicable, Interventional, and Basic science
This study aims to investigate the effects of an 8-week dietary intervention on cognitive function, stress, and the gut microbiota in healthy adults with low fibre intake.
The gut microbiota communicates bidirectionally with the brain via the microbiota-gut-brain axis to influence various aspects of human physiology, including host metabolism, immune function, behaviour, and cognition. Diet is a key modulator of the microbial composition, suggesting that the microbiota could explain the association between poor nutrition and decreasing health of the population. Dietary fibre is the main energy source for the gut microbiota and fundamentally impacts its composition and function. The microbiota-gut-brain axis has been proposed to mediate some of the effects of dietary fibre on the brain, for example through microbial metabolites (e.g., short-chain fatty acids (SCFA)), regulation of the immune system, and the microbial impact on gut hormones and neurotransmitters. Similarly, intake of fermented foods is positively associated with cognitive health and has been shown to alter the microbiota composition and function and exert an anti-inflammatory effect. However, no studies to date have examined the singular and combined effects of fermented and fibrous foods on the gut microbiota, cognition, and emotion. The present study aims to determine the role of diet on the microbiota-gut-brain axis and mental health.
Using a randomized-controlled, parallel, single-blinded design, participants consuming a habitually low fibre diet (N=200) will undergo an 8-week dietary intervention. Participants will receive one of four diets (n=50 in each group): high fibre (aim 24-35 grams/day), fermented foods (aim 4-6 portions/day), combined diet of fermented foods and high fibre (aim 25-30g/day of fibre and 3-4 servings/day of fermented foods) or control (dietary education according to national Irish guidelines). Cognitive, psychological, and biological measures will be compared at baseline and endpoint. During the intervention period, individuals will provide repeated faecal samples to assess temporal microbial changes.
University College Cork is the lead sponsor of 116 studies on the registry; 23 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Participants will recieve dietary education based on the healthy eating guidleines provided by the Health Service Executive (HSE).
Other: Control
Fermented foods diet (4-6 portions/day)
Other: Fermented Foods
High fibre diet (24-35 grams/day)
Other: High Fibre
Combined diet high in fibre and fermented foods (fibre aim 24-35 grams/day, fermented foods aim 4-6 portions/day)
Other: Combined Diet
Participants will recieve dietary education to include 4 to 6 portions of fermented foods to their normal diet.
Participants will recieve dietary education to increase their fibre intake to 24-35g/day in their normal diet.
Participants will recieve dietary education to increase their fibre intake to 25-30g/day and include 3 to 4 portions of fermented foods to their normal diet.
Participants will recieve dietary education based on the Irish healthy food pyramid.
Trait stress/mood: self-report
self-report questionnaires
Time frame: Change from baseline at 8 weeks
Trait stress/mood: hypothalamic-pituitary-adrenal axis activity
Cortisol from saliva samples
Time frame: Change from baseline at 8 weeks
Responses to acute stress: self-report
Self-report questionnaires
Time frame: Change from baseline at 8 weeks
Responses to acute stress: sympathetic-adrenal-medullary pathway activity
Galvanic skin response taken from the skin on the hand
Time frame: Change from baseline at 8 weeks
Responses to acute stress: hypothalamic-pituitary-adrenal axis activity
Cortisol from saliva samples
Time frame: Change from baseline at 8 weeks
Cognitive performance: working memory
Spatial Working Memory
Time frame: Change from baseline at 8 weeks
Cognitive performance: episodic memory
Modified Rey Auditory Verbal Learning Test (ModRey)
Time frame: Change from baseline at 8 weeks
Cognitive performance: decision making
Iowa Gambling Task
Time frame: Change from baseline at 8 weeks
Cognitive performance: emotional inhibition
Emotional Stroop
Time frame: Change from baseline at 8 weeks
Cognitive performance: sustained attention
Rapid Visual Information Processing
Time frame: Change from baseline at 8 weeks
Cognitive performance: visual pattern recognition memory
Pattern Recognition Memory
Time frame: Change from baseline at 8 weeks
Cognitive performance: cognitive flexibility
Intra-Extra Dimensional Set Shifting
Time frame: Change from baseline at 8 weeks
Cognitive performance: social cognition
Emotion Recognition Task
Time frame: Change from baseline at 8 weeks
Cognitive performance: affective perceptual bias
Emotional Bias Task
Time frame: Change from baseline at 8 weeks
Microbiota composition and function
Shotgun metagenomics of fecal samples
Time frame: Change from baseline at 8 weeks
Microbial and host metabolomics
Untargeted metabolomics analysis
Time frame: Change from baseline at 8 weeks
Inflammation
Inflammatory markers in lipopolysaccharide stimulated and unstimulated bloods
Time frame: Change from baseline at 8 weeks
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
University College Cork