Composed of hundreds of coexisting species, the intestinal microbiota is shaped by competition within a niche limited by nutrient availability, environmental conditions, competitors, predators, and host genetics. The availability of nutrients within the intestinal tract is fundamentally linked to diet - something that has undergone profound changes in the preceding 100 years. The industrialization of food processing and manufacturing has not only resulted in a significant increase in the consumption of simple carbohydrates, but also resulted in the addition of novel sugars, non-calorific sweeteners, oils, and emulsifiers to the food chain. Despite safety testing in animals, the effect of these nutrients on the microbiota is mostly unknown.

Focusing primarily on the hospital-associated pathogens Clostridioides difficile (formerly Clostridium difficile) and Vancomycin-Resistant Enterococci (VRE), we examine how dietary components can drive infectivity, selection, spread, and virulence of enteric pathogens.