 However, in a 2015 study of 26 commercial vegetarian dog diets available in the United States, 25% were found to not meet the minimum nutritional requirements as established by AAFCO.Studies have demonstrated that a plant-based diet can be just as edible and palatable as animal-based diets for dogs.Odiferous ingredients that enhance the smell of the food increase palatability, and examples include nutritional yeast, vegetable oil, nori (seaweed), as well as spirulina.