Studies of the gut microbiome have gone to the dogs—and pets around the world could benefit as a result. In a paper published this week in mBio, researchers from Nestle Purina PetCare Company report that the ratio of proteins and carbohydrates in a canine’s daily diet have a significant influence on the balance of microbes in its gut. Among other findings, they observed that dogs fed a high-protein, low-carbohydrate diet had decreases in the ratio of Bacteroidetes to Firmicutes bacteria, as well as enriched microbial gene networks associated with weight loss in humans. The microbial responses were more pronounced in obese and overweight dogs than in dogs of a healthy weight.