Grain-free and exotic ingredient diets in dogs have become increasingly popular in the past 20 years amongst pet owners partly because of very clever marketing from the pet food industry at large. 

Unfortunately this has led to an increasing number of dogs being diagnosed with heart disease including in breeds not normally prone to cardiomyopathy, a form of heart disease.

In 2018, the FDA and a group of veterinary cardiologists issued a warning about grain-free diets and their relationship with heart disease in dogs. 

It was initially thought that grain-free diets caused a deficiency in taurine, an essential amino-acid, and although taurine is still implicated in some cases of cardiomyopathy (particularly in susceptible breeds like the Golden Retriever and the Cocker Spaniel) it is now understood that the causality between heart disease and grain-free diets might be more complex than initially thought. 

Studies so far have linked legumes, especially peas and lentils, to a higher incidence of dilated cardiomyopathy in dogs. According to Dr Lisa Freeman, veterinary nutritionist at Tufts: “some astute cardiologists noticed higher rates of DCM including Golden retrievers and in some atypical dog breeds.  They also noticed that both the typical and atypical breeds were more likely to be eating boutique or grain-free diets, and diets with exotic ingredients – kangaroo, lentils, duck, pea, fava bean, buffalo, tapioca, salmon, lamb, barley, bison, venison, and chickpeas.  Even some vegan diets have been associated.  It has even been seen in dogs eating raw or home-prepared diets.”

Research is ongoing and at this time it is still recommended to avoid grain-free diets or at least have an honest conversation with your veterinarian about nutrition and report any symptoms of weakness, intolerance to exercise, difficulty breathing, coughing or fainting since these could be symptoms of heart disease.

Dr. Caroline Simard-Swimmer

Medical Director and Co-Founder

Pets After Dark