Probiotics, Gut-brain axis, and stress: A review of nutritional therapeutics

Abstract

The intricate connection between the gut and the brain, known as the gut-brain axis, has garnered increasing attention in recent years, particularly regarding its role in mental health and stress regulation. Emerging evidence highlights the influence of gut microbiota on neural, endocrine, and immune pathways, suggesting that modulation of the gut environment can have profound effects on psychological well-being. Probiotics—live microorganisms that confer health benefits to the host—have shown promising potential in supporting gut health and, consequently, mental health. This review explores the current understanding of the gut-brain axis and the role of probiotics as a nutritional therapeutic in stress management. Key mechanisms include the production of neuroactive compounds such as serotonin and gamma-aminobutyric acid (GABA), modulation of systemic inflammation, and regulation of the hypothalamic-pituitary-adrenal (HPA) axis. While preclinical and clinical studies indicate that specific probiotic strains may alleviate stress-related symptoms and improve mood, further research is required to standardize probiotic interventions and clarify strain-specific effects. This review emphasizes the therapeutic promise of probiotics in stress-related disorders and underscores the need for integrative approaches in nutritional psychiatry.