Heart Health in Dogs: Diet Plays a Role
By Jennifer Evans
Our last blog post focused on feeding your pet a raw diet. This led us to a recent alert from the Food and Drug Administration that may link certain grain-free dog foods to a canine heart condition known as Dilated Cardiomyopathy.
Dilated Cardiomyopathy is a type of canine heart disease that affects the heart muscle that results in weakened contraction and poor pumping ability. As the disease progresses, the heart chambers may enlarge, valves may begin to leak, and congestive heart failure may develop.
Historically, certain large breeds are prone to the disease: Boxers, Doberman Pinschers, Great Danes, Newfoundlands, Irish Wolfhounds, and St. Bernards. Occasionally, German Shepherds, Cocker and Springer Spaniels can contract the disease.
DCM may manifest itself initially as a reduced ability to exercise and reduced stamina. Your pet could experience fainting episodes or extreme weakness and lack of appetite. Eventually, a soft cough, as though the dog is clearing its throat, may develop.
The FDA is now investigating a potential link between certain grain-free dog foods and the development of DCM. The foods in question are those that have legumes, such as peas or lentils, seeds, or potatoes (mainly sweet potatoes) listed as the top ingredients. The FDA began investigating when they received reports of dog breeds developing this disease that were not in the previous list of those breeds prone to DCM.
The FDA took notice when a broad range of dog breeds, but particularly Golden Retrievers, were being reported by veterinarians as contracting DCM in the early 2000’s. The majority of these dogs were eating “boutique” dog foods containing exotic ingredients such as kangaroo, duck, buffalo, salmon, lamb, bison, venison, lentils, peas, fava beans, tapioca, barley, or chickpeas as major ingredients. In the industry, these boutique foods are known as BEG: Boutique companies, Exotic Ingredients, Grain Free. In BEG diets, it seems that lentils, peas, fava beans, tapioca, barley, or chickpeas are the main ingredients used to replace grains such as wheat or corn in order to make the food grain-free. Exotic proteins such as kangaroo, duck, buffalo, salmon, lamb, bison, and venison are often used in addition to chicken or beef.
The recent study about DCM published in the Journal of American Veterinary Medical Association published on December 1, 2018 explores the reasons why a broad range of dog breeds, but particularly Golden Retrievers, are now being reported as increasingly contracting DCM. It appears that most of these dogs were eating a BEG diet with exotic proteins and grain replacements discussed above. These dogs can be separated into two categories of dogs with diet-related DCM:
- Dogs with DCM related to Taurine deficiency
- Dogs with DCM with separate but yet unknown dietary factors
It must be noted that the veterinary cardiologists interviewed for this study reported that both groups of dogs noted above were mostly eating BEG diets, but the true percentage of those eating BEG diets is not known.
The dogs with DCM related to taurine (a crucial amino acid) deficiency were followed for 12 to 24 months after taurine supplementation and a diet change. All but 1 had significantly improved heart function.
The findings regarding the dogs with DCM who did not have a taurine deficiency are a little less conclusive. Some improved with just a change from one BEG diet to another, leading researchers to conclude that a specific ingredient in one BEG diet was causing the DCM, but not necessarily the grain-free status of the diet. Some improved with a change in diet and taurine supplementation, even though their blood tests did not indicate taurine deficiency. Further research is being done on the specific ingredients of BEG diets and a possible link to choline, copper, l-carnitine, magnesium, thiamine, or vitamin E and selenium deficiencies, which have also been linked to heart issues in dogs. The nutritional properties of the exotic BEG ingredients have not been sufficiently studied.
The bottom line is that researchers do not yet know the specific cause for the rise in DCM cases in non breed-related dogs. In those dogs not having a taurine deficiency, the diet-related cause of DCM needs to be studied more. Dog owners should consult with their veterinarian about diet should their pet exhibit any signs of DCM.