Background: The development of the gut microbiome during early life plays a critical role in shaping long-term health. The first 1,000 days represent a crucial period in which the microbiome is particularly malleable, influenced by various factors such as birth mode, diet, antibiotic exposure, and environmental interactions.
Summary: This review outlines the key stages of microbiome maturation, beginning with initial colonization at birth and progressing through the diversification and stabilization phases during the first 5 years of life. Factors like breastfeeding, the introduction of solid foods, and early-life antibiotic have a critical impact on microbial diversity and immune system development. Disruptions to the microbiome during this critical window, particularly through antibiotic use, are associated with an increased risk of immune, metabolic, and neurodevelopmental disorders. Recent research emphasizes the need for a better understanding of these early-life trajectories to inform interventions that promote a healthy microbiome.
Keywords: Colonization patterns; Diversity; Early life; Gut microbiome; Host-microbe interactions; Microbiome maturation.
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