AUTHOR=Walden Kylie E. , Moon Jessica M. , Hagele Anthony M. , Allen Leah E. , Gaige Connor J. , Krieger Joesi M. , Jäger Ralf , Mumford Petey W. , Pane Marco , Kerksick Chad M. 

TITLE=A randomized controlled trial to examine the impact of a multi-strain probiotic on self-reported indicators of depression, anxiety, mood, and associated biomarkers

JOURNAL=Frontiers in Nutrition

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2023.1219313

DOI=10.3389/fnut.2023.1219313

ISSN=2296-861X

ABSTRACT=<sec id="sec1"><title>Objective</title><p>To examine the efficacy of supplementing with a multi-strain probiotic (MSP) on changes associated with mood, anxiety, and neurotransmitter levels.</p></sec><sec id="sec2"><title>Method</title><p>In a randomized, double-blind, placebo-controlled fashion, 70 healthy men and women (31.0 ± 9.5 years, 173.0 ± 10.4 cm, 73.9 ± 13.8 kg, 24.6 ± 3.5 kg/m<sup>2</sup>) supplemented with a single capsule of MSP (a total daily dose of 4 × 10<sup>9</sup> live cells comprised of a 1 × 10<sup>9</sup> live cells dose from each of the following strains: <italic>Limosilactobacillus fermentum</italic> LF16, <italic>Lacticaseibacillus rhamnosus</italic> LR06, <italic>Lactiplantibacillus plantarum</italic> LP01, and <italic>Bifidobacterium longum</italic> 04, Probiotical S.p.A., Novara, Italy) or a maltodextrin placebo (PLA). After 0, 2, 4, and 6 weeks of supplementation and 3 weeks after ceasing supplementation, study participants completed the Beck Depression Inventory (BDI-II), State-Trait Anxiety Inventory (STAI), and Leiden Index of Depression Sensitivity (LEIDS-R) questionnaires and had plasma concentrations of cortisol, dopamine, serotonin, and C-reactive protein determined.</p></sec><sec id="sec3"><title>Results</title><p>BDI, STAI, and total LEIDS-R scores were reduced from baseline (<italic>p</italic> &lt; 0.05) with MSP supplementation after 4 and 6 weeks of supplementation and 3 weeks after supplementation while no changes (<italic>p</italic> &gt; 0.05) were reported in PLA. When compared to PLA, MSP scores for state anxiety, trait anxiety, and LEIDS-R (hopeless, aggression, rumination, and total score) were significantly lower (<italic>p</italic> &lt; 0.05) after supplementation. Plasma serotonin concentrations in MSP were increased from baseline after 6 weeks of supplementation and 3 weeks after ceasing supplementation. No changes (<italic>p</italic> &gt; 0.05) in plasma dopamine, C-reactive protein, or cortisol concentrations were observed between groups.</p></sec><sec id="sec4"><title>Conclusion</title><p>MSP supplementation resulted in widespread improvements in several questionnaires evaluating mood, anxiety, and depression in young, healthy men and women. MSP supplementation increased serotonin increased after 6 weeks of MSP supplementation with no change in dopamine, C-reactive protein, or cortisol.</p></sec><sec><title>Clinical trial registration</title><p><ext-link xlink:href="https://classic.clinicaltrials.gov/ct2/show/NCT05343533" ext-link-type="uri" xmlns:xlink="http://www.w3.org/1999/xlink">https://classic.clinicaltrials.gov/ct2/show/NCT05343533</ext-link>, NCT05343533.</p></sec>