ABSTRACT:
Urbanization and dietary acculturation among Indigenous populations are consistently associated with reduced gut microbiome diversity 1,2,3 and increased prevalence of chronic conditions such as type 2 diabetes and obesity⁴. In contrast, traditional Indigenous diets frequently include fermented foods that introduce beneficial microbes and enhance gut microbial resilience5,6. These effects are mediated through short-chain fatty acid (SCFA) production, anti-inflammatory metabolites, and strengthened gut barrier integrity7,8. This narrative review synthesizes evidence on how Indigenous fermentation practices support microbiome stability and reduce chronic disease risk in urbanized Indigenous communities, with emphasis on decolonizing public health approaches. A comprehensive literature search was conducted in PubMed, Scopus, and Web of Science for studies published between January 2018 and December 2025. Keywords included traditional fermented foods, Indigenous, gut microbiome, urbanization, chronic disease. Studies addressing Indigenous fermentation practices, microbiome composition, and chronic disease outcomes in traditional versus urbanized contexts were included. Traditional fermented foods common in Indigenous African and Amazonian communities are associated with increased gut microbial diversity and enrichment of fiber-degrading taxa such as Prevotella and Treponema 9-11 enhancing polysaccharide metabolism and SCFA production 7,12. Urban migration is linked to loss of these taxa, increased Bacteroides dominance, reduced diversity, and higher prevalence of inflammation and metabolic disorders 13,14. Continued consumption of fermented foods moderates seasonal microbiome variation and reduces dysbiosis in agrarian communities, indicating potential for restoring microbial resilience among urban Indigenous populations through community-driven initiatives5,15. Interventions retaining traditional fermentation practices report reduced inflammatory markers and improved metabolic outcomes. Indigenous fermentation practices are associated with gut microbiome profiles distinct from those shaped by urbanization and westernized diets. Integrating these practices into health interventions for urban Indigenous communities may reduce metabolic and inflammatory disease risk while advancing decolonized microbiome research. Longitudinal, community-partnered studies are needed to evaluate culturally grounded dietary interventions and long-term health outcomes.