One of the biggest conversations in the veterinary industry world right now is what to feed our pets. The short answer is there are a lot of options out there and there is not one right answer for every pet.
It is important to understand the terminology being used to describe pet food and nutrition. A raw diet is one that contains uncooked proteins, such as raw chicken or venison. Limited-ingredient diets contain just one protein and one carbohydrate source: for example, chicken and brown rice. Grain-free foods use a non-grain source of carbohydrates like green peas, oatmeal, or potato, and an exotic protein is one that is not normally found in pet foods (like kangaroo).
Grain-free diets are usually cooked foods. Pet owners often choose these foods to avoid “fillers” or because their pet has allergies. Feeding a grain-free diet also parallels current human diet trends: keto diets, the Atkins diet, etc.
New information has come to light about the long-term effects of feeding pets a grain-free diet, and unfortunately it may not be all good. Recent and on-going studies show a link between grain-free diets and the development of dilated cardiomyopathy (DCM), a condition where the heart muscle becomes very thin and weak and eventually gives out. The reason appears to be the lack of taurine, an essential amino acid, in these diets, as well as the presence of taurine-blocking ingredients like legumes and lentils. DCM is a fatal condition, and while medications can help a pet who has been diagnosed with this heart condition, there is no cure.
As far as allergies go, only about 10-15% of allergies in pets are food-related—the remaining 85-90% are environmental, so avoiding grains will not help the majority of dogs and cats. Pets who have a confirmed food allergy are often placed on a limited ingredient diet, but it does not have to be grain-free. And as for fillers, the important thing is to remember that pets have very different nutritional requirements from people. They benefit greatly from some things in their diet that we as humans wouldn’t dream of eating—chicken livers, for example.