 But what they don't realize is that dog system is kind of like going on one of those no-carb diets for people or whatever. Your system actually changes. And to switch to a higher-carbohydrate diet in the summer and switch to a higher-fat diet in the winter, it's really you're not doing your dog any favors. You're better off just keeping your dog on a higher-protein and fat diet year-round and just reduce the amount you're feeding and be happy that you save a couple bucks on dog food.