Final answer:
The gut microbiota reaches an adult-like state around the age of 2 to 3 years, influenced by various early life factors and then remains relatively stable throughout life.
Step-by-step explanation:
The approximate age at which the gut microbiota reaches an adult-like state is by the age of 2 to 3 years. During early life, the microbiome is influenced by factors such as delivery mode, feeding regime (breastfeeding versus infant formula), and environmental exposures. The gut microbiome becomes essentially established and reaches a steady state around 2 to 3 years, after which it remains relatively stable but still responds to variations in diet, lifestyle, and the host’s health.