Dietary Supplements, Probiotics, Metabolism, Food Preferences, Microbiota
Conditions
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.
Interventions
BEHAVIORALInhibitory 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
PROCEDUREBlood samples
Hormone levels will be analyzed from blood samples obtained before and after a caloric preload given at each visit
BIOLOGICALFeces 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.
PROCEDURECaloric 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.
BEHAVIORALFood 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
BEHAVIORALMemory task
Participants perform short memory tasks on each visit
BEHAVIORALFood consumption task
Participants are given a selection of food items to consume on each visit
Sponsors
Uppsala University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
MALE
Age
18 Years to 28 Years
Healthy volunteers
Yes
Inclusion criteria
* Male * Age 18-28y * Healthy (self-reported) and not on medication * Non-smoking * Normal sleep-wake rhythm (i.e. 7-8 h per night, self-reported via diaries) * Regular meal patterns with daily breakfast
Exclusion criteria
* Major illness * Taking any serious medications * Any sleep conditions (e.g. irregular bedtimes, sleep complaints) * Any dietary issues with the food items provided * Current or history of endocrine, neurological or psychiatric disorders * Shift work in the preceding three months or for a long duration * Time travel over a significant number of time zones in the preceding two months * Too much weight gain or weight loss in the preceding three months * Excessive intake of fermented dairy products * Intake of probiotics * Recent antibiotic treatment (last 6 months) * Recent intake of certain dietary supplements * Excessive caffeine (\>5 cups daily) or alcohol intake (\>2 alcohol units daily)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| 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. |
| 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 |
| 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. |
| 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. |
Countries
Sweden
Contacts
Primary ContactJonathan Cedernaes, M.D., PhD
Backup ContactChristian Benedict, PhD
Outcome results
None listed