title: Obesity and the gut microbiome: Striving for causality.
abstract: The gut microbiome has been proposed to play a causal role in obesity. Here, we review the historical context for this hypothesis, highlight recent key findings, and critically discuss issues central to further progress in the field, including the central epistemological problem for the field: how to define causality in the relationship between microbiota and obesity phenotypes. Definition of such will be critical for the field to move forward.
authors.affiliation: Division of Molecular Immunology, Cincinnati Children's Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA.
authors.forename: Isaac T W
authors.initials: IT
authors.lastname: Harley
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Karp
keywords: Innate immunity; Microbiome; Microbiota; Non-alcoholic fatty liver disease; Obesity; Segmented filamentous bacteria; Type 2 diabetes
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