This review focuses on the potential health benefits of probiotics and live microorganisms as therapeutic agents for mental and emotional disorders. Through mechanisms, including modulation of immune responses, control of the hypothalamic-pituitary-adrenal (HPA) axis, maintenance of the gut barrier, and synthesis of important neurotransmitters, we examined their effects on anxiety, depression, stress-related disorders, cognitive function, and emotional well-being. Some clinical trials have shown positive results, and the generalizability of these findings is limited due to inconsistencies in probiotic strains, dosages, and research methods, although several studies have reported beneficial results. Ultimately, this study highlights the potential of tailored probiotics to fill these gaps in our understanding of the relationship between humans and probiotics.
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