Effects of Prebiotics on Cognition and Health

Study Overview
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Brief Summary
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This research intervention aims to examine the effects of prebiotic consumption on changes in behavioral and biological measures of cognition and stress among adults.

Detailed Description
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Evidence-based dietary strategies provide behavioral means benefiting physical and cognitive function. Pertinent to the proposed work, dietary intake has been recently shown to have the potential to directly influence the gut microbiota composition as well as brain function. Specifically, the consumption of prebiotics or fibers metabolized by gut bacteria may also play a role. These foods are readily available in the marketplace, however, their implications for physical and cognitive function are not clear. Accordingly, the proposed study aims to investigate effects of prebiotic beverage consumption on changes in behavioral and biological measures of cognition and stress among adults.

Official Title
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The Effects of Prebiotics on Behavioral and Biological Markers of Cognition and Stress

Conditions
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Physiological Stress, Cognitive Change, Gastrointestinal Health

Intervention / Treatment
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* Other: Lactose Free 1% Milk
* Other: Lactose Free 1% Milk + 10 g prebiotic


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Males and females Between the ages of 25-45 years at the time of consent BMI ≥18.5 kg/m2 Normal or corrected-to-normal vision based on the minimal 20/20 standard in order to complete the cognitive task. Ability to drop-off fecal sample within 15 minutes of defecation Exclusion Criteria: Current pregnancy or lactation Tobacco use Dairy allergy or intolerance Prior diagnosis of metabolic and gastrointestinal disease (cardiovascular disease and type 1 or type 2 diabetes, chronic constipation, diarrhea, Crohn's disease, celiac disease, ulcerative colitis, irritable bowel syndrome, diverticulosis, stomach or duodenal ulcers, hepatitis, HIV, cancer, etc.) Prior diagnosis of cognitive or physical disability, including ADHD, severe asthma, epilepsy, chronic kidney disease Use of any anti-psychotic, anti-depressant, antianxiety, or ADD/ADHD medications Use of medications that alter normal bowel function and metabolism (e.g., recent antibiotic use, laxatives, enemas, anti-diarrheal agents, narcotics, antispasmodics, diuretics, anticonvulsants). Prior malabsorptive bariatric surgery (i.e. gastric bypass, sleeve gastrectomy) or restrictive bariatric surgery (i.e. adjustable gastric band)

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Participants will pass through 2 arms, control and prebiotic, in a randomized, counterbalanced order.
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Control<br>4-5 week period where participant will consume control beverage | Other: Lactose Free 1% Milk<br>* 8 oz of study beverage daily<br>* Other names: Control;|
| Experimental: Prebiotic<br>4-5 week period where participant will consume the intervention beverage | Other: Lactose Free 1% Milk + 10 g prebiotic<br>* 8 oz of study beverage supplemented with 5 grams of fructooligosaccharide and 5 grams of galactooligosaccharide<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Biological markers of stress | Changes in 24-hour urinary cortisol, inflammatory markers (e.g. IL-6, CRP). | 4-5 weeks | 
| Behavioral markers of stress | Change in reported questionnaire responses specific to depression, stress, and anxiety using the Depression, Anxiety, and Stress (DASS) Questionnaire. | 4-5 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gastrointestinal Microbiota composition | Impact on bacterial genera abundances. | 4-5 weeks | 
| Gastrointestinal microbiota beta-diversity | Impact on beta-diversity measures | 4-5 weeks | 
| Gastrointestinal Microbiota alpha-diversity | Impact on alpha-diversity measures | 4-5 weeks | 
| Cognitive function | Computer tasks will be used to assess working memory, interference control, cognitive flexibility, and hippocampal function/relational memory | 4-5 weeks | 
| Sleep | The Pittsburg Sleep Quality Index (PSQI) will also be used to assess sleep, as will actigraphy. | 4-5 weeks |