A few years ago, I wrote a blog article about grain-free diets and discussed their pros and cons.
The summary at that time was that although grain-free diets were popular due to a lot of marketing influence, we didn't have any medically substantiated benefits for these diets. However, at that time it was also not known for there were any problems with these diets. Since then, the FDA has published information about their knowledge of a link between grain-free diets and a type of heart disease called dilated cardiomyopathy in dogs.
Dilated cardiomyopathy is a form of heart disease where the walls of the heart thin over time as the heart becomes enlarged. This decreases the heart's contractility and ability to work to pump blood and therefore can lead to congestive heart failure. Unfortunately, it is often impossible for owners to see any signs of this disease before congestive heart failure develops. There are some breeds such as Dobermans and Great Danes that are genetically prone to developing this disease without dietary influence, but with the new development of diet-related cardiomyopathy, there have been reports of this disease in many other breeds.
While the specific link to disease development is still being researched, it is believed to be due to a lack of certain nutrients in the food. The foods reported by the FDA contained a high percentage of legumes, lentils, or peas. The highest number of cases have been reported in Golden Retrievers. However, it is believed that many other cases may be under-reported in other breeds, and in general, the number of cases is likely much higher than what has been reported. You may be surprised to find cases reported in many popular brands of dog foods. There is a list present on the FDA's website.
What does this mean if your dog is currently eating a grain-free diet? At this time, we do recommend switching your dog to a commercial diet with grains. It appears that this form of heart disease can be reversible with diet change if it has not progressed to needing additional medical treatment. In the past, there has been an over-representation of media regarding the benefits of grain-free diets heavily influenced by the comparison of gluten-free trends in people. Studies have shown that grains are actually one of the lowest percentages of allergens in dogs and that food-allergic dogs make up less than 5% of our dogs with allergies.
If you have any questions about appropriate diets for your pets please reach out to us at Hillcrest Animal Hospital. You can learn more about the FDA's statement on grain-free diets on their website.