Nutrition, microbiota, and autism: how gut flora influences child development

This article summarizes how the gut microbiome, the immune system, and the central nervous system interact via the gut–brain axis to influence autism spectrum disorder (ASD) development. Early-life microbiota disturbances (antibiotics, hospital exposure, formula feeding) can produce dysbiosis, impair intestinal barrier function, and promote systemic and neuroinflammation. These changes may alter neurodevelopmental processes (neurogenesis, synaptogenesis, myelination), neurotransmitter systems, and microglial activation. Selective eating common in children with ASD can worsen nutrient deficiencies and microbiome imbalance. Clinical and experimental evidence — including microbiota transfer from children with ASD to germ-free mice and trials of microbiota transfer therapy (MTT/FMT) — indicate the microbiome can affect gastrointestinal and behavioral symptoms, though current evidence does not support microbiome modification as a definitive cure for ASD. Future research should clarify mechanisms linking neuroinflammation and microbiota alterations and determine safe, effective microbiome-based interventions.