The exposome and the human oral microbiome through the one health lens

OBJECTIVES: To map and synthesise current evidence on how lifelong biological, environmental, and social exposures, collectively conceptualised as the exposome, interact with the human oral microbiome to influence oral disease development and progression within a One Health framework. DESIGN: A scoping review was conducted to identify peer-reviewed studies published in English that examined the relationships between the exposome and the human oral microbiome. The review followed the Arksey and O'Malley framework, applying its five-stage methodological approach. Comprehensive searches were performed in MEDLINE, Embase, PsycInfo, Scopus, Web of Science, and CINAHL. Study quality was assessed using the Joanna Briggs Institute (JBI) tools, and results were reported in accordance with PRISMA-ScR guidelines. RESULTS: A total of twenty-nine studies were included in this review. These showed that health status, non-communicable diseases, medication use, and psychosocial factors influence the biodiversity, abundance, and function of the human oral microbiome. Other studies suggested that animal interactions and physical and chemical exposures can alter host-microbiome interactions, as well as microbial community dynamics within the oral cavity. While the studies reviewed used reliable methods and standardized protocols, they were of moderate quality due to small sample sizes, potential reverse causality, and limited control for confounding and multiple testing. CONCLUSION: This review highlights the complexity of the human oral microbiome and its interactions with the various components of the exposome, emphasizing the focus on disease impact and health behaviours, while noting a gap in research on non-bacterial communities, interaction mechanisms, and long-term effects on dysbiosis.