Adolescent and Adult Gut Microbiota The gut microbiota acquired as an infant shapes the diversity of the microbiome into adulthood(6). Human gut microbiota begins developing into an adult-like composition within three years after birth. The interpersonal differences in gut microbiota is greater among children and adolescents than in adults, but the diversity of gut microbiota is observed to be greater in adults than children. For example, phylotypes belonging to Bifidobacterium significantly declined with age, which had previously dominated the infant gut flora, while the overall operational taxonomic unit (OTU), observed in children and adults, increases with age. The difference or similarities between the gut microbiota data does not support a strong genetic inheritability, as …show more content…
When comparing the gut microbiota of breast fed infants to elderly adults from the United States, Malawians, and Amerindians, a significant difference in diversity in flora was observed. The United States had the least diversity out of the three. A western lifestyle affects the gut microbiota in a negative way when compared to a non-western lifestyle. The typical US diet is rich in protein, while diets in Malawi and Amerindian populations consist of corn and cassava. The difference in microbiomes associated with the diet differences are parallel to those observed between carnivorous and herbivorous mammals. An overrepresentation of the number of enzymes involved in the degradation of amino acids such as aspartate, proline, glutamine, ornithine, and lysine were observed. An overrepresentation of enzymes that were involved in the degradation of simple sugars, sugar substitutes, and host glycans were also observed in the US gut microbiome. The gut microbiome observed in Malawians and Amerindians had an overrepresentation of α-amylase, which is involved in the degradation of