Over the past several years, grain-free pet foods have become increasingly popular among dog owners. While many pets do well on these diets, veterinary researchers have been investigating a possible connection between some grain-free diets and a type of heart disease called dilated cardiomyopathy (DCM). Below is an overview of what’s currently known — and what pet owners should consider.
The FDA Investigation
In 2018, the U.S. Food and Drug Administration (FDA) began investigating reports of DCM in dogs that were eating certain ‘grain-free’ or boutique-style diets. These diets often contained high levels of peas, lentils, chickpeas, or potatoes in place of traditional grains. While an association was observed, the FDA has not confirmed a direct cause-and-effect relationship between grain-free diets and heart disease.
You can read the FDA’s full Q&A; on this topic here: https://www.fda.gov/animal-veterinary/an imal-health-literacy/questions-answers-fda-center-veterinary-medicines-investigation-possible -connection-between-diet-and
What Studies Have Found
A study from the University of California, Davis, examined 24 golden retrievers diagnosed with DCM and low taurine levels. Nearly all of these dogs had been fed grain-free or legume-rich diets. After switching to a different diet and receiving taurine supplementation, many of the dogs’ heart function improved — suggesting a potential link between diet and reversible heart disease in some cases.
However, more recent peer-reviewed studies (such as those published in the Journal of Animal Science) have shown that when diets are properly formulated and balanced according to AAFCO standards, grain-free formulas do not necessarily lead to heart problems in healthy dogs. This highlights the importance of overall nutrient balance rather than simply whether a diet contains grains.
Possible Risk Factors
• Diets that list peas, lentils, chickpeas, or potatoes among the first several ingredients • Diets from boutique or small pet food companies with limited nutritional testing or research
• Dogs that are predisposed to DCM (Dobermans, Great Danes, Boxers, Golden Retrievers, Irish Wolfhounds)
• Feeding homemade or exotic-ingredient diets without veterinary nutritionist guidance Recommendations for Pet Owners
• Choose diets that meet AAFCO feeding trial or formulation standards. • Ask your veterinarian or a board-certified veterinary nutritionist for diet recommendations.
• Avoid diets where peas, lentils, or potatoes appear as main ingredients, unless prescribed by your vet.
• If your dog is currently on a grain-free diet, do not panic — discuss it with your vet before making changes.
• Monitor for signs of heart disease (lethargy, coughing, weakness, fainting, decreased stamina) and contact your veterinarian if you notice any symptoms.
• Prescription diets require annual exams.
Summary
While the FDA and veterinary researchers continue to investigate the possible link between certain grain-free diets and DCM, no definitive cause has been proven. The best approach is to focus on feeding a complete, balanced diet from a reputable company with solid nutritional research. For most pets, there is no medical reason to avoid grains, and well-formulated grain-inclusive diets remain safe and healthy choices.
Have questions about your pet’s diet or heart health? Schedule a nutrition consultation with our veterinary team today.