The Relationship Between Diet, Cognition, Stress, and the Gut Microbiota

Healthy Clinical Trial

— NMB  

Official title:

The Relationship Between Diet, Cognition, Stress, and the Gut Microbiota: A Cross-sectional Study in Healthy Adults

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT05931536
• Other study ID #: APC150a
• Status: Recruiting
• Start date: July 14, 2022
• Est. completion date: July 2024

Study information

• Verified date: June 2023
• Source: University College Cork
• Contact: Elizabeth Schneider, PhD
• Phone: (+353) 021 4901721
• Email: eschneider[@]ucc.ie
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

This study aims to investigate the relationship between diet and the microbiota-gut-brain axis.

Description:

Dietary fibre is well-known for its many health benefits, including the support of gastrointestinal, metabolic, and mental health. Although studies investigating whole dietary patterns in relation to cognition have demonstrated that diet quality and a healthy dietary pattern are associated with better cognitive performance, the role of dietary fibre in this regard is understudied. It is now understood that the gut microbiota (trillions of microbes inhabiting the gastrointestinal tract) communicates bidirectionally with the brain to influence mental health and cognition. Importantly, dietary fibre has been shown to positively affect the microbiota composition. The aim of this study is to understand the effects of dietary fibre on the microbiota-gut-brain axis.

Using a cross-sectional design, habitual low fibre (<=18 grams/day, n=200), moderate fibre (18.1-24.9 grams/day, n=75), and high fibre (=>25 g/day, n=75) consumers will be compared at baseline on measures of cognition, responses to acute and chronic stress, and biological markers of the microbiota-gut-brain axis.

The investigators hypothesize that participants with higher dietary fibre intake at baseline will perform better in the cognitive tasks compared to individuals with low fibre intake, and that this difference can, in part, be mediated by the gut microbiota.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 350
• Est. completion date: July 2024
• Est. primary completion date: July 2024
• Gender: All
• Age group: 18 Years to 50 Years

Eligibility

Inclusion Criteria:

• Be able to give written informed consent.

• Be between 18 and 50 years of age.

• Have a body mass index (BMI) between 18.5-29.9 Kg/m2.

• Be in generally good health as determined by the investigator.

Exclusion Criteria:

• Are less than 18 and greater than 50 years of age.

• Have a BMI below 18.5 or above 29.9 Kg/m2.

• Have a significant acute or chronic coexisting illness [cardiovascular, gastrointestinal (GI) [to include functional GI disorders, inflammatory bowel disease, coeliac disease, lactose intolerance, food allergies], immunological, psychiatric [to include formal or as determined by MINI Psychiatric interview, diagnosis of current major depression, anxiety disorder, bipolar spectrum disorder, schizophrenia, other DSM-IV Axis I disorder], neurodevelopmental disorders, immunological, metabolic disorders [to include type I or II diabetes], or any condition which contraindicates, in the investigators judgement, entry to the study.

• Have a condition or taking a medication that the investigator believes would interfere with the objectives of the study, pose a safety risk, or confound the interpretation of the study results; all psychoactive medications [to include anxiolytics, antipsychotics, antidepressants, anticonvulsants, centrally acting corticosteroids, and opioid pain relievers), laxatives, enemas, antibiotics, anti-coagulants, over-the counter non-steroidal anti-inflammatories (NSAIDS). Subjects should have a wash-out period of 4 weeks.

• Current prebiotic or probiotic supplement use (a wash-out period of 4 weeks after cessation will allow entry to the study).

• Females who are peri-menopausal, menopausal or post-menopausal.

• Females who are pregnant or planning a pregnancy, or lactating.

• Participants who are not fluent in English.

• Are colour blind.

• Have dyslexia or dyscalculia.

• Are a current habitual daily smoker.

• Individuals who, in the opinion of the investigator, are considered to be poor attendees or unlikely for any reason to be able to comply with the trial.

• Subjects receiving treatment involving experimental drugs. If the subject has been in a recent experimental trial, these must have been completed not less than 30 days prior to this study.

• Have a malignant disease or any concomitant end-stage organ disease.

• Have completed a study in our laboratory in the past 4 years.

Related Conditions & MeSH terms

• Healthy

Intervention

Other:
• Dietary fibre
Habitual dietary consumption from a variety of foods will be assessed using 7-day food logs entered by the participant and assessed for accuracy by a dietitian.

Locations

Country	Name	City	State
Ireland	APC Microbiome Ireland	Cork

Sponsors (1)

Lead Sponsor	Collaborator
University College Cork

Country where clinical trial is conducted

Ireland, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Trait stress/mood: self-report	Self-report questionnaires	Compared at baseline
Primary	Trait stress/mood: hypothalamic-pituitary-adrenal axis activity	Cortisol from saliva samples	Compared at baseline
Primary	Responses to acute stress: self-report	Self-report questionnaires	Compared at baseline
Primary	Responses to acute stress: hypothalamic-pituitary-adrenal axis activity	Cortisol from saliva samples	Compared at baseline
Primary	Responses to acute stress: sympathetic-adrenal-medullary pathway activity	Galvanic skin response taken from the skin on the hand	Compared at baseline
Secondary	Cognitive performance: working memory	Spatial Working Memory	Compared at baseline
Secondary	Cognitive performance: episodic memory	Modified Rey Auditory Verbal Learning Test (ModRey)	Compared at baseline
Secondary	Cognitive performance: decision making	Iowa Gambling Task	Compared at baseline
Secondary	Cognitive performance: emotional inhibition	Emotional stroop	Compared at baseline
Secondary	Cognitive performance: sustained attention	Rapid Visual Information Processing	Compared at baseline
Secondary	Cognitive performance: visual pattern recognition memory	Pattern Recognition Memory	Compared at baseline
Secondary	Cognitive performance: cognitive flexibility	Intra-Extra Dimensional Set Shifting	Compared at baseline
Secondary	Cognitive performance: social cognition	Emotion Recognition Task	Compared at baseline
Secondary	Cognitive performance: affective perceptual bias	Emotional Bias Task	Compared at baseline
Secondary	Microbiota composition and function	Shotgun metagenomics of fecal samples	Compared at baseline
Secondary	Microbial and host metabolites	Untargeted metabolomics analysis in fecal and urine samples	Compared at baseline
Secondary	Inflammation	Inflammatory markers in lipopolysaccharide stimulated and unstimulated bloods	Compared at baseline