Effect of a Multi-Strain Probiotic Supplementation to Manage Stress during the COVID-19 Pandemic: A Randomized, Double-Blind, Placebo-Controlled, Cross-Over Clinical Trial.

INTRODUCTION: The COVID-19 pandemic strongly affected every aspect of the modern society, from health to socioeconomics, leading people to experience high levels of stress. METHODS: A double-blind, cross-over, placebo-controlled clinical study was performed to investigate the ability of a food supplement containing two probiotic strains, Limosilactobacillus reuteri PBS072 and Bifidobacterium breve BB077, in supporting 33 healthy adults, working at a university, in stress management. The efficacy of the tested strains in influencing the stress response, in terms of mood and sleep behavior, was assessed using the following validated questionnaires: Profile of Mood State (POMS) and Pittsburgh Sleep Quality Index (PSQI). RESULTS: Outcomes of the POMS and the PSQI demonstrated a significant reduction of the questionnaire's scores both versus baseline and placebo after 30 days of probiotic intake. CONCLUSIONS: According to the results, the probiotic food supplement investigated showed a remarkable effect on stress management by improving the quality of sleep and the mood.