By Charlie Powell, College of Veterinary Medicine

Dog owners concerned about grain‑free diets causing heart disease have a professional opinion to help them now thanks to veterinary cardiologists at Washington State University’s College of Veterinary Medicine.

The statement from WSU was written in response to an increase in reports recently concerning dogs that were fed grain‑free diets. Some reports claim dilated cardiomyopathy (DCM) may be caused by these newer and often trendy diets which are grain free or contain legumes or exotic proteins. To see the complete statement from WSU, see the WSU VetMed website.

A suspected cause of DCM is taurine, a type of amino acid and a building block of proteins. Taurine is found in large amounts in the brain, retina, heart, and in blood cells called platelets. It is also an additive to many human energy drinks.

DCM is a condition in which the heart enlarges and can’t pump blood efficiently. It is caused by diseased heart muscle, usually beginning in the main pumping chamber, the left ventricle. While DCM may not be severe enough to cause symptoms, in other cases it can be life threatening even fatal due to an irregular heartbeat and congestive heart failure.

“While there has historically been some evidence of diet‑responsive DCM in some breeds (golden retrievers, Cocker spaniels, Newfoundlands, Irish wolfhounds, and Saint Bernards), the incidence of DCM in these breeds has appeared to increase when they were fed grain‑free, vegetarian/vegan, or exotic ingredient pet foods,” explained Lynne Nelson, a professor and board‑certified veterinary cardiologist at WSU. “Curiously, other cases occur in breeds without a history of DCM or in very young dogs.”

Here’s what caring owners need to know based on currently available research:

  • Some of the latest dog food formulations may not be balanced with regard to amino acids or may not be well‑absorbed by the pet. But it is not clear whether taurine deficiency causes DCM or if the two things occur coincidentally or whether DCM may be related to other dietary components.
  • Some breeds may be more susceptible to nutritional changes such as taurine deficiency, and this may suggest breed‑related differences in metabolism.
  • Dogs with DCM that have been eating diets described above, may reverse the condition if it is caught early. They may also respond to dietary changes and taurine supplementation regardless of whether or not they have normal levels of taurine in their blood.

“People with dogs they suspect have diet‑associated DCM should save food samples and product labels of all dietary components they are feeding” said Nelson. “This includes the main ration, as well as all treats, chews and supplements.

“With complete information in hand, your veterinarian or the owner can report such cases to the FDA (see the FDA website). In all cases, your veterinarian can best help your pet.”