Cognitive and Metabolic Effects of a Probiotic Supplement
Study Details
Study Description
Brief Summary
To examine the cognitive and metabolic effects of a probiotic supplement that is readily and already available for purchase in public drug stores. This study is a double-blinded randomized cross-over placebo-controlled intervention study. Participants will be randomized to receive either the probiotic supplement or the placebo during the first intervention period which will last 2 weeks. This will be followed by a washout period, after which they will proceed to the second intervention period, also lasting 2 weeks and also followed by a washout period.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
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N/A |
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Active Comparator: Probiotic Probiotic pills given for 2 weeks, during one of the interventions that the participants is either randomized to as the first or second intervention period. At day 0 and following each intervention period (at week 2 and week 6), participants will be tested using Inhibitory task, Blood samples, Feces collection, Caloric preload, Food selection task, Memory task and Food consumption task. |
Behavioral: Inhibitory task
Participants perform a binary decision on each presented stimuli. Of the two possible outcomes, participants are instructed to make a motor response (go) for one type, and are to withhold a response (no-go) for the other type. Reaction time and accuracy are measured for each event
Procedure: Blood samples
Hormone levels will be analyzed from blood samples obtained before and after a caloric preload given at each visit
Biological: Feces collection
Feces samples will be collected on the morning of each visit, before and after each 2-week intervention period, as well as after each 2-week washout period following each intervention period.
Procedure: Caloric preload
A caloric preload will be given to participants, following which blood will be taken at 65 minutes later (specified in Blood sampling) following the ingestion of the caloric preload.
Behavioral: Food selection task
Participants are given the opportunity to write and use a computer program to specify amount and type of food would ideally like to consume
Behavioral: Memory task
Participants perform short memory tasks on each visit
Behavioral: Food consumption task
Participants are given a selection of food items to consume on each visit
|
| Placebo Comparator: Placebo Placebo pills given for 2 weeks, during one of the interventions that the participants is either randomized to as the first or second intervention period. At day 0 and following each intervention period (at week 2 and week 6), participants will be tested using Inhibitory task, Blood samples, Feces collection, Caloric preload, Food selection task, Memory task and Food consumption task. |
Behavioral: Inhibitory task
Participants perform a binary decision on each presented stimuli. Of the two possible outcomes, participants are instructed to make a motor response (go) for one type, and are to withhold a response (no-go) for the other type. Reaction time and accuracy are measured for each event
Procedure: Blood samples
Hormone levels will be analyzed from blood samples obtained before and after a caloric preload given at each visit
Biological: Feces collection
Feces samples will be collected on the morning of each visit, before and after each 2-week intervention period, as well as after each 2-week washout period following each intervention period.
Procedure: Caloric preload
A caloric preload will be given to participants, following which blood will be taken at 65 minutes later (specified in Blood sampling) following the ingestion of the caloric preload.
Behavioral: Food selection task
Participants are given the opportunity to write and use a computer program to specify amount and type of food would ideally like to consume
Behavioral: Memory task
Participants perform short memory tasks on each visit
Behavioral: Food consumption task
Participants are given a selection of food items to consume on each visit
|
Outcome Measures
Primary Outcome Measures
- Memory function [Change in memory function assessed at baseline (week 0), post-intervention 1 (at week 2), pre intervention 2 (week 6), post intervention 2 (week 8) and post-washout intervention 2 (week 12)]
Memory test to examine the influence of probiotic supplement compared with placebo on memory function (declarative and working memory)
Secondary Outcome Measures
- Glycometabolic regulation [Change in glycometabolic regulation assessed at baseline (week 0), post-intervention 1 (at week 2), pre intervention 2 (week 6), post intervention 2 (week 8) and post-washout intervention 2 (week 12)]
Glucose, insulin and other hormonal values during fasting and 1 hour following a standardized caloric preload
- Food preferences [Change in food preferences assessed at baseline (week 0), post-intervention 1 (at week 2), pre intervention 2 (week 6), post intervention 2 (week 8) and post-washout intervention 2 (week 12)]
Will test whether participants food preferences are changed following each intervention, as compared with before each intervention. Test will be written and computer-based.
- Inhibitory task [Change in inhibitory task performance assessed at baseline (week 0), post-intervention 1 (at week 2), pre intervention 2 (week 6), post intervention 2 (week 8) and post-washout intervention 2 (week 12)]
Participants perform a binary decision on each presented stimuli. Of the two possible outcomes, participants are instructed to make a motor response (go) for one type, and are to withhold a response (no-go) for the other type. Reaction time and accuracy are measured for each event.
- Food consumption task [Change in food consumption task assessed at baseline (week 0), post-intervention 1 (at week 2), pre intervention 2 (week 6), post intervention 2 (week 8) and post-washout intervention 2 (week 12)]
Participants will be offered a food selection and their consumption will be measured.
- Sleep patterns [Change in sleep patterns as assessed at baseline (week 0), post-intervention 1 (at week 2), pre intervention 2 (week 6), post intervention 2 (week 8) and post-washout intervention 2 (week 12)]
- Microbiome changes [Microbiome assessed at baseline (week 0), post-intervention 1 (at week 2), pre intervention 2 (week 6), post intervention 2 (week 8) and post-washout intervention 2 (week 12)]
Changes in microbiome will be assessed following treatment with either placebo or probiotics; feces will be collected according to standardized criteria.
Eligibility Criteria
Criteria
Inclusion Criteria:
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Male
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Age 18-28y
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Healthy (self-reported) and not on medication
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Non-smoking
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Normal sleep-wake rhythm (i.e. 7-8 h per night, self-reported via diaries)
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Regular meal patterns with daily breakfast
Exclusion Criteria:
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Major illness
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Taking any serious medications
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Any sleep conditions (e.g. irregular bedtimes, sleep complaints)
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Any dietary issues with the food items provided
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Current or history of endocrine, neurological or psychiatric disorders
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Shift work in the preceding three months or for a long duration
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Time travel over a significant number of time zones in the preceding two months
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Too much weight gain or weight loss in the preceding three months
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Excessive intake of fermented dairy products
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Intake of probiotics
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Recent antibiotic treatment (last 6 months)
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Recent intake of certain dietary supplements
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Excessive caffeine (>5 cups daily) or alcohol intake (>2 alcohol units daily)
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Department of Neuroscience, Uppsala University | Uppsala | Sweden | 75324 |
Sponsors and Collaborators
- Uppsala University
Investigators
- Principal Investigator: Christian Benedict, PhD, Department of Neuroscience, Uppsala University
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- FF8vsPlaceboJC2013