Grain-Free Diets and Heart Disease in Dogs – What’s the Link?


In recent years, so-called “grain-free” pet foods have exploded in popularity as they have been promoted as more delicious, nutritious, and closer to the diet of Fido’s ancestors.  Many of these popular foods’ main ingredients are a novel protein – such as bison, rabbit, or kangaroo – with potatoes, peas, lentils or other legumes.  In July of 2018, the U.S. Food and Drug Administration’s Center for Veterinary Medicine announced that it is investigating the potential link between a common type of heart disease, dilated cardiomyopathy (DCM), and certain “grain-free” pet foods.  The veterinarians at Family Pet Animal Hospital want you to be informed about what this means (and doesn’t mean) for you and your dog.

What sparked the FDA’s investigation?

Dilated cardiomyopathy is typically seen in certain large breed dogs, such as Great Danes, Saint Bernards, and Doberman Pinschers, as well as Cocker Spaniels. Evidence suggests that certain breeds are genetically susceptible to the disease.  The CVCA, a group of veterinary cardiologists in the eastern United States, alerted the FDA to atypical cases of DCM seen in a Shih Tzu, Golden and Labrador Retrievers, a Whippet, Miniature Schnauzers, and other mixed breeds.  According to the FDA, “early reports from the veterinary cardiology community indicate that the impacted dogs consistently ate foods containing peas, lentils, other legume seeds, or potatoes as main ingredients in their primary source of nutrition for time periods ranging from months to years.  That’s why the FDA is conducting an investigation into this potential link.”

What is dilated cardiomyopathy (DCM)?

Dilated cardiomyopathy is a disease of the heart muscle that results in weakened contractions and poor pumping ability.  A progression of the disease results in the heart becoming enlarged and signs of congestive heart failure may develop.  Symptoms of DCM may include lower exercise tolerance, fatigue, excessive panting, difficulty breathing, coughing, and fainting, although early signs may be subclinical.


Is there a link between grain-free pet foods and dilated cardiomyopathy?

A link between these grain-free pet foods and DCM has not been confirmed and no recalls have been issued.  Although researchers have not ruled out other potential causes, the common factor among the dozens of reported cases of DCM in breeds that are not genetically susceptible to the disease was a diet heavy in legumes (e.g. beans, peas, lentils, peanuts) and potatoes – carbohydrates used to replace grains such as wheat, barley, oats, and rice.

In some of these uncharacteristic cases of DCM, low levels of taurine, an essential amino acid, have been noted.  Researchers speculate that legumes may interfere with the dog’s ability to make or absorb taurine.  However, taurine levels in other affected dogs have been normal, leaving researchers puzzled.  No definitive conclusions have yet been reached.

Aren’t grain-free foods better for my dog?

Lisa Freeman, a veterinary nutritionist and researcher at Tufts University, says grain-free pet diets should be viewed with skepticism.  “Contrary to advertising and popular belief, there is no research to demonstrate that grain-free diets offer any health benefits over diets that contain grains,” Freeman recently told the New York Times.  Grains are an important source of protein and other nutrients in many meat-based pet foods, she continued. “Grains have not been linked to any health problems except in the very rare situation when a pet has an allergy to a specific grain.”

My dog is on a grain-free diet.  Should I switch my dog’s food?

We recognize that the decision about what food to feed your pet is a very personal one.  Given that there are no definitive conclusions yet regarding a potential link between grain-free diets and dilated cardiomyopathy, and there are many other individual factors to consider (breed, health status, etc.), the doctors here at Family Pet Animal Hospital recommend that you seek the advice of your pet’s veterinarian to make an informed decision.

Family Pet Animal Hospital’s Position Statement Regarding Grain-Free Diets

  • Based upon recommendations from veterinary cardiologists at this time, if your pet appears healthy and is currently eating a grain-free diet from a pet store, consider changing your pet’s diet or supplementing your pet’s diet with taurine (ask your veterinarian how to do this).
  • If you do not wish to change your pet’s diet, consider testing taurine levels and/or a consult with a cardiologist to evaluate your pet’s heart.
  • If your pet has been prescribed a grain-free diet due to an illness, contact your veterinarian before considering any changes to your pet’s diet. Prescription, limited-ingredient diets have been used in veterinary medicine for decades without any negative side-effects and we do not recommend a change from these diets at this time.
  • Because the number of reported cases suggestive of a potential link between grain-free diets and dilated cardiomyopathy is small and no definitive conclusions have yet been reached, many questions remain unanswerable at this time. We are confident that more details will become available in the near future and we will continue to be forthcoming with all new information.

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Family Pet Animal Hospital


1401 W. Webster Avenue Chicago, IL 60614

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