Exploring the Influence of Urbanization on Gut Mycobiota through Dietary Changes in Burkina Faso

Abstract Background How the evolution of dietary habits has impacted the yeasts associated with our gut is largely unknown. The impact of urbanization and globalization on human nutrition and the composition of gut microbial communities are considered driving forces behind the rise in non-communicable diseases. While previous studies in developing countries have investigated changes in the bacterial component of the gut microbiota during the transition from rural to urban areas, the modifications in the intestinal fungal communities are completely unexplored. In this study, we examined the impact of urbanization and dietary shifts on the composition of the gut mycobiota in families residing in rural, semi-urbanized, and urban areas in Burkina Faso. We compared these findings with families living in the urban area of Florence (Italy) as a reference for a globalized lifestyle. Results Our research revealed a significant reduction in the alpha diversity of the intestinal mycobiota as individuals transitioned from rural to urban areas. Members of rural households exhibited greater fungal richness and biodiversity compared to those in urban households, including affluent families in the capital city, Ouagadougou. We observed that the fungal diversity varied in households as a function of the rural-to-urban transition gradient, and we identified 33 fungal amplicon sequence variants (ASVs), including 12 fungal species, as associated with distinct areas with specific lifestyle and dietary patterns as indicators of the rural-to-urban transition. Conclusion The household-level survey of rural and urban communities in Burkina Faso highlighted the effect of urbanization on the lifestyle and subsequent composition of the participants' intestinal mycobiota. A greater diversity of fungal taxa emerged in the rural cohort, along with the presence of distinct species with potential pathogenic traits. This finding suggests that the continuous exposure to pathogenic fungi and the ensuing interaction with the immune system may contribute to the maintenance of lower incidence and severity of non-communicable diseases (NCDs) in non-globalized communities. In agreement with the “hygiene hypothesis”, the lack of yeast diversity could provide a potential explanation for the higher prevalence of inflammatory and immune-related disorders in urbanized regions across the world.