Probiotics on Stress-associated Gastrointestinal Function in University Students

In this randomized, double-blind, placebo-controlled study, undergraduate students planning
to take a fall final exam will receive a daily probiotic combination, individual probiotic,
or placebo for 6 weeks. Questionnaires will assess gastrointestinal symptoms, immune health,
stress and stress management, quality of life, diet, adverse events, and compliance. In a
subset of subjects, stool samples will be collected at baseline and at week 5 of the
intervention (the week before final exams) to characterize microbial communities.

Inclusion Criteria:

- At least 18 years of age

- Healthy full-time undergraduate student at the University of Florida

- Willing and able to consume a daily supplement (probiotic or placebo) for the duration
of the 6-week study

- Willing and able to complete daily questionnaires online regarding general health and
well-being, including stress levels and gastrointestinal symptoms (Note: we will
recruit participants who will have Internet access for the duration of the protocol,
but understand that, once enrolled, situations may change. If this is the case, paper
copies of the online forms will be provided)

- Willing to discontinue any immune-enhancing dietary supplements (e.g., prebiotics and
fiber supplements, probiotics, Echinacea, fish oil, vitamin E [>400% of the RDA or >60
mg/day])

- Had a cold/flu within the past year

Exclusion Criteria:

- Currently smoke

- Women who are lactating, know that they are pregnant, or are attempting to get
pregnant

- Currently taking any systemic corticosteroids

- Currently being treated for any physician-diagnosed diseases

- Have received chemotherapy or other immune suppressing therapy within the last year