title: The gut microbiota and obesity: from correlation to causality.
abstract: The gut microbiota has been linked with chronic diseases such as obesity in humans. However, the demonstration of causality between constituents of the microbiota and specific diseases remains an important challenge in the field. In this Opinion article, using Koch's postulates as a conceptual framework, I explore the chain of causation from alterations in the gut microbiota, particularly of the endotoxin-producing members, to the development of obesity in both rodents and humans. I then propose a strategy for identifying the causative agents of obesity in the human microbiota through a combination of microbiome-wide association studies, mechanistic analysis of host responses and the reproduction of diseases in gnotobiotic animals.
authors.affiliation: State Key Laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University. Ministry of Education Key Laboratory for Systems Biomedicine, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang Campus, Shanghai 200240, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Zhao
mesh_terms: D000818:Animals; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006801:Humans; D064307:Microbiota; D009765:Obesity / Q000382:microbiology*
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