LAUSR

Significance The long-term impacts of infection on the microbiota and its regulation of host physiology are poorly understood. Here, we report that long-term alterations to the gut microbiota following a single, acute episode of bacterial or protozoan gut infection can remodel host metabolism to preferentially and more efficiently consume carbohydrates. This infection-triggered metabolic remodeling ultimately results in white adipose tissue expansion and host weight gain. Furthermore, in the context of low limited nutrient availability, infection-triggered carbohydrate metabolism benefits host fitness by preventing host stunting. Our study suggests a new perspective in which infection (pathogen-induced stress) can be co-opted as a cue to prime host adaptation to nutritional stress.