The Pediatric Microbiota–Gut–Brain Axis: Implications for Neuropsychiatric Development and Intervention

Background: The gut microbiota plays a crucial role in brain development and function, especially in early life. Disruptions in the pediatric microbiota-gut-brain axis have been linked to neurodevelopmental and psychiatric disorders. We hypothesize that early-life dysbiosis can perturb neurodevelopment via the pediatric microbiota-gut-brain axis, increasing risk and/or severity of neuropsychiatric outcomes, and that microbiota-targeted strategies may mitigate this risk. Methods: We conducted a narrative review by searching PubMed, Scopus, and Web of Science up to January 2025 for studies addressing pediatric microbiota, neuropsychiatric development, and interventions. Human and animal studies were included if they provided mechanistic or clinical insights. Results: Key determinants of microbiota development in childhood include mode of delivery, feeding practices, antibiotic exposure, diet, and environment. Altered microbial composition has been associated with autism spectrum disorder, attention-deficit/hyperactivity disorder, mood disorders, anxiety, and anorexia nervosa. Mechanistic pathways involve immune modulation, neural signaling (including the vagus nerve and enteric nervous system), and microbial metabolites such as short-chain fatty acids. Interventions targeting the microbiota-ranging from dietary strategies and probiotics to psychobiotics and fecal microbiota transplantation-show promise but require further pediatric-focused trials. Conclusions: The pediatric microbiota-gut-brain axis represents a critical window for neuropsychiatric vulnerability and intervention. Early-life strategies to support a healthy microbiota may help reduce the risk or severity of psychiatric disorders. Future research should prioritize longitudinal pediatric cohorts and clinical trials to translate mechanistic insights into precision interventions.