Diet, gut microbiota composition and feeding behavior

Advances in sequencing technologies have allowed for a more complete analysis of the microbiota composition and identification of differences among individuals and/or physiologies. Changes in microbiota composition and associated inflammation have been linked to both metabolic and behavioral disorders, and abnormality in microbiota composition, or dysbiosis, may play a causal role in the etiology and maintenance of these pathologies. There is accumulating evidence showing that the gut microbiota can communicate to the central nervous system to alter host behavior. Supplementation with L. rhamnosus in mice notably causes a decrease in anxiety. Interestingly, these effects are abolished by vagotomy, identifying the vagus nerve as a potential communication route for microbiota-originating signals. Chronic high fat feeding notably leads to remodeling of the vagal afferent pathway and is associated with an increase in energy intake; these effects appear to be mediated by microbiota-induced inflammation. Therefore, preventing bacterial-driven inflammation, via dietary manipulation for example, may have potential therapeutic effects for both metabolic and behavioral disorders.