LE3 .A278 2015

2015

Potter, Susan

Acadia University

Bachelor of Science

Honours

Psychology

Psychology

The relationship between gastrointestinal symptoms and mental health symptoms, and the effects of probiotics on gastrointestinal and mental health symptoms, was examined in a double-blind, crossover design clinical trial in which participants consumed a probiotic powder (Lactobacillus helveticus and Bifidobacterium longum) and placebo powder, each for five weeks, separated by a two-week wash-out period. One third of participants were assigned to a wait-list control group during the first five weeks of the study before beginning the intervention phases. The mental health measures (ASI, SCL-90R, MADRS and STAI) and gastrointestinal measure (GSRS) were completed at the beginning and end of each phase, and a daily mood and bowel health questionnaire (DMBQ) was completed every day for the duration of the study. Fifty-five participants completed the first phase and forty-nine of these completed the second phase; thirty-five participants were included in the longitudinal gastrointestinal data analyses due to missing DMBQ data. Despite the small sample size, there were significant correlations between gastrointestinal and mental health measures. Additionally, a relationship between minor diarrhea and the consumption of probiotics was observed. However, no significant differences between the probiotic and placebo groups were found for the gastrointestinal variables.

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https://scholar.acadiau.ca/islandora/object/theses:1187