What is Dilated Cardiomyopathy?

What is Dilated Cardiomyopathy?

In recent years, grain-free dog food has become increasingly popular, with pet owners opting for alternatives to traditional dog foods, believing that grain-free is healthier for their pets. However, this trend has also raised concerns about a potential link between grain-free diets and heart disease in dogs. 

This article delves into the current evidence, the potential causes, and the correlation between grain-free dog food and heart disease in dogs, particularly dilated cardiomyopathy (DCM).

Dilated cardiomyopathy is a disease that affects the heart muscle, causing it to enlarge and weaken. This can lead to a decreased ability of the heart to pump blood, which may ultimately result in heart failure. While certain breeds are predisposed to DCM, such as Dachshunds and Mini Schnauzers, recent studies have suggested that diet may also play a role in the development of the disease.

The FDA Investigation

In 2018, the U.S. Food and Drug Administration (FDA) announced an investigation into a potential link between grain-free diets and DCM in dogs. This was prompted by a noticeable increase in DCM cases among dogs not typically predisposed to the disease. 

The FDA examined more than 500 cases of DCM in dogs and found that a significant proportion of the affected animals were on grain-free diets, which often contained high levels of legumes, pulses, or potatoes.

Possible Causes and Correlations

The potential connection between grain-free dog food and DCM may be attributed to several factors:

Taurine deficiency

Taurine, an amino acid, is crucial for maintaining heart health in dogs. Some studies have suggested that grain-free diets may be low in taurine or that the high levels of legumes and pulses in these diets may interfere with taurine absorption. However, not all dogs with DCM on grain-free diets have been found to have low taurine levels, suggesting that other factors may also be involved.

Reduced bioavailability of essential nutrients

The presence of certain ingredients in grain-free diets, such as legumes and pulses, may inhibit the absorption of essential nutrients like amino acids, which are necessary for maintaining heart health. This could contribute to the development of DCM in dogs.

Genetic predisposition

While certain breeds are genetically predisposed to DCM, the recent increase in cases among dogs not typically predisposed to the disease suggests that other factors, such as diet, may also play a role. 

It is possible that some dogs may have a genetic predisposition that makes them more susceptible to developing DCM when exposed to certain dietary triggers.

Current Evidence and Limitations

Despite the FDA investigation and multiple studies, the evidence connecting grain-free diets to DCM in dogs remains inconclusive. Some studies have found a link between grain-free diets and DCM, while others have not. Moreover, the number of dogs affected by DCM while on a grain-free diet is still relatively small compared to the overall dog population.

The limitations of the current evidence include the lack of controlled, long-term studies and the reliance on observational data. Additionally, there may be confounding factors, such as genetic predisposition, that have not been fully accounted for in the existing research.

Recommendations and Precautions

While the connection between grain-free dog food and heart disease remains inconclusive, pet owners should consult with their veterinarian to discuss their dog’s specific dietary needs. Veterinarians may recommend certain diets or supplements based on a dog’s breed, age, weight, and overall health.

For dogs predisposed to DCM or those with a history of heart disease, pet owners should be especially cautious when selecting a grain-free diet. In such cases, it may be beneficial to choose a diet that has undergone feeding trials and has been formulated by a board-certified veterinary nutritionist. 

Pet owners should also be vigilant for signs of DCM, including lethargy, rapid breathing, coughing, and weakness, and seek online emergency veterinary care immediately if any of these symptoms are observed.

In light of the potential connection between grain-free diets and DCM, some experts recommend that pet owners consider diets containing high-quality, whole-grain sources

Whole grains, such as brown rice, barley, and quinoa, can provide essential nutrients and may not pose the same risks as grain-free diets with high levels of legumes and pulses.

It is important for pet owners to remember that each dog is unique and may have different dietary requirements. Regular check-ups with a veterinarian, including monitoring heart health and discussing dietary needs, are essential to ensuring that a dog is receiving the proper nutrition.


The link between grain-free dog food and heart disease, specifically dilated cardiomyopathy, remains uncertain. While some evidence suggests a connection, more research is needed to establish a definitive link and to understand the underlying mechanisms. Until more conclusive evidence is available, pet owners should work closely with their veterinarians to select the most appropriate diet for their dog, taking into account factors such as breed, age, weight, and overall health. 

Monitoring a dog’s health, being vigilant for signs of heart disease, and seeking prompt veterinary care when needed are essential steps in maintaining the well-being of our canine companions.