The gut microbiome belonging to Colombian adults of younger generations has shifted to a more westernized composition compared to older generations

Communities undergoing westernization experience changes to their lifestyle and diet. These changes are associated with decreased levels of activity, increased levels of obesity, increased risk for cardiometabolic disease, and changes to the microbiome composition. Obese individuals tend to have reduced levels of diversity and increased abundance of potentially pathogenic bacteria. Additionally, aging has been associated with increased levels of diversity, which can be linked to changes in lifestyle. In this study, we examined the impact of obesity, defined by waist circumference and body fat percentage, on the gut microbiome of individuals in the middle of westernization. Our study also explored the relationship between gut microbiome composition and obesity across multiple generations. Within our dataset, there was no significant difference in alpha diversity between obese and healthy individuals but there was a significant difference in diversity between two age groups, 18-28 and 38-48. Taxonomic analysis revealed that the age group 18-28 was defined by taxa Bifidobacterium and Bacteroides which are marker taxa for a westernized microbiome, and the age group 38-48 was defined by upregulation of Prevotella, a marker taxa for a non-westernized diet. Taken together, our results indicate that our defined obesity metrics do not have an impact on the gut microbiome of individuals in the midst of westernization. Our results instead highlight the possibility that younger generations may have been more affected by westernization than older generations. Our study has the potential to add to our growing understanding of westernization and its varying impacts across generations.