Amongst the veterinary community, concerns have been raised of an association between grain-free diets and acquired dilated cardiomyopathy (DCM) in dogs. These concerns prompted investigation by the US Food and Drug Administration (FDA), announced in July 2018.

While observations by veterinary medicine clinicians have driven identification of important causal factors of veterinary diseases, it is essential that these observations are subject to rigorous scientific investigation before conclusions are drawn. This approach is the cornerstone of evidence-based medicine, contributes to understanding of the pathophysiology of disease, and informs objective decision making at the regulatory level. By these standards, the hypothesis that grain-free diets are associated with acquired DCM in dogs has not yet been adequately explored and requires further investigation in accordance with well-published and accepted epidemiological principles that enable robust inference.