Grain Free Diets: Fad or Fact?
Everyone has read about or seen a TV commercial about feeding your dog or cat a grain free diet. So where did the belief of grain free diets come from? If your dog descended from the wolf and your cat from the tiger, it would make sense that their wild ancestors survived on a diet of predominately meat. But, considering the average life span of a wolf or even a feral dog or cat is 4-6 years, is there a benefit to feeding grain free to the animals we have domesticated over the past 10,000-14,000 years?
Start with the Facts
Let’s start with looking at some facts:
- Removing the grain from a diet does not mean the meat content increases. It means that grains are removed and replaced with a starch (potatoes, legumes, or rice). So, the carbohydrate content of the pet food remains the same.
- Over the thousands of years of domestication, the gastro-intestinal tract of the dog and cat has changed and adapted to a diet more similar to that of their humans as a result of us feeding them what we typically eat. Their bodies recognize food by the nutrients it provides not the source of the carbohydrate. The body does not recognize that it is a potato or a grain of wheat, it just utilizes the nutrients contained within the source.
- If you compare the nutrient profile of a grain free diet to that of a grain containing diet, they are surprisingly similar. Grains are an important source of fiber, essential fatty acids, and other nutrients that help to decrease the total fat and calories in a diet. They are also a very affordable source of nutrition.
- Grains are a very uncommon cause of food allergies in pets. True food allergies are fairly rare in pets and the most common ingredients reported to cause allergies are proteins (beef, dairy, chicken, egg, and fish).
So, Where’s the Beef
There is actually no scientific evidence to either support or refute the claims that grain free is better when it comes to dogs and cats. So where did this notion come from? It came from small pet food manufacturer’s as a means of getting their foot in the door of a $7 billion-dollar industry. By offering a product that no one else offered and using a marketing strategy that worked in the human food industry (gluten free is healthier), they were able to corner a small portion of the market (because let’s be real, even 0.5% of 7 billion is $35 million).
As a veterinarian, I didn’t have a bias one way or the other. As long as it was a high-quality diet that appeared nutritionally complete, I wasn’t concerned if the carbohydrates came from a grain or a starch, until now.
But Here’s the Fallout
As the foods have now been commercially available for several years, Veterinarians are beginning to report an increase in heart disease in dogs and finding a possible connection to grain free diets. While the evidence is still pending, there does seem to be a connection between diets that use legumes (peas and lentils) and Dilated cardiomyopathy (DCM). Legumes contain lower levels of several amino acids (specifically taurine, cysteine, and methionine) that are needed for normal function of the cardiac muscle. There appear to be some breeds of dog (Cocker Spaniels, Newfoundlands, and possibly Golden Retrievers) as well as some dogs in general that lack the genetic ability to metabolize adequate amounts of taurine. If these dogs are fed a diet with a lower amount of amino acids, it may increase their risk of developing DCM. The studies are still ongoing, and the veterinary community is waiting as patiently as possible for the answers.
Still Have Questions?
While I don’t recommend you run out and change your pet’s diet, I would recommend that you consult with your veterinarian to determine the best diet for your pet, especially if it is a breed that is pre-disposed to heart disease.
For more information on grain free diets and DCM, go here: