Can Grain-Free Diets Cause Heart Disease in Dogs?

In 2018, it was becoming apparent that veterinary cardiologists were seeing an increase in the incidence of Dilated Cardiomyopathy (DCM). DCM is a relatively rare heart disease leading to congestive heart failure. Historically, most cases of DCM have been seen in specific breeds (Irish Wolfhounds, Doberman Pinschers, Great Danes, and Boxers) and thought to have a genetic predisposition. However, the recent spike in cases has involved several other breeds of dog not known to have a genetic predisposition to DCM (including mixed breeds). In many of these cases, diet is believed to play a role. This prompted the United States FDA to issue a statement in July 2018 warning the public about these potential concerns.

While the role of specific nutrients and/or ingredients involved in the diets fed to these dogs has yet to be determined, some common features have been observed. Most of the recent Diet-related DCM cases have been fed so-called “BEG” diets. BEG is an acronym for Boutique, Exotic ingredients, Grain-free.

  • Boutique diets are manufactured by smaller companies, often without an employed veterinary nutritionist. They are also frequently without the rigorous quality control measures in place that would typically be found at a larger reputable food company.
  • Exotic ingredients include unusual meat sources such as Kangaroo or Venison and large quantities of legumes or pulses. The only circumstances where these types of diets are specifically indicated are in cases of dietary allergies. They have no added nutritional benefit in regular maintenance diets.
  • Grain-free diets have become increasingly popular. There is no scientific evidence to support any advantage of a grain-free diet over more traditional corn, rice, or wheat-based diet. Grains are nutritious and safe to feed to dogs.

Unfortunately, marketing tactics rather than scientific data tend to drive consumer behaviour, making BEG foods increasingly popular. The minimum standards to be achieved in a dietary formulation to allow the product to be sold as pet food are low. They do not guarantee a fully balanced, nutritious food.

Some of the recent diet-related DCM cases have been shown to be deficient in taurine (an amino acid essential to heart function). However, others have had normal taurine levels, so it is not thought to be the only nutrient involved.

Further investigation into diet-related DCM is ongoing, and until we have a clearer picture of the exact cause(s), it is best to avoid feeding BEG diets and consult with a veterinarian if you have concerns about the diet you are feeding. If your dog is showing symptoms of heart disease such as slowing down on walks, coughing, fainting, or trouble breathing, it is essential to have a veterinarian examine him or her.

Dr. Lisa Freeman, a Veterinary Nutritionist working out of Tufts University has a great nutrition website. Click here to read an article she wrote on questions to ask and factors to consider in selecting the best diet for your pet. Click here to read her current findings and experience with recent diet-related DCM cases.

In conclusion, diet-related DCM has recently become a more common cause of heart disease in dogs. We still do not have a full understanding of all the factors that are associated with this condition. There is significant evidence implicating so-called BEG diets as a common factor in the reported cases.

Please consult with your veterinarian if you have any concerns about the diet you are currently feeding your dog, or if your dog is showing signs of heart disease.

Written by: Dr. Rael Rifkind, DVM