InvestigatorsMatter for Mallory


Dog diagnosed with heart disease after being fed grain-free diet

FDA is investigating a link between the two
Posted at 6:10 AM, Mar 19, 2019
and last updated 2021-03-18 12:54:08-04

FALLSTON, Md. — Alison Sheaffer noticed her double doodle, Nyla, had some thinning on her nose and decided to take her to the veterinarian for a check-up. Nyla was prescribed thyroid medication, but after having an adverse reaction to one pill, Sheaffer brought her back to the vet.

"So I took her back, and he did an X-ray of her to make sure she didn't have any obstructions, and then they found the enlarged heart," said Sheaffer, a Fallston resident.

Nyla was diagnosed with advanced dilated cardiomyopathy (DCM), a heart muscle disease that can lead to heart failure.

"She still has a pretty significantly enlarged heart, her muscle function's abnormal, her heart rate's controlled which is a really good sign," said Dr. Steven Rosenthal, a board-certified veterinary cardiologist with CVCA Cardiac Care for Pets.

While large breeds are more prone to the disease, Nyla's age, just five-years-old, made Dr. Rosenthal question her diet. Sheaffer switched Nyla's diet last June to a grain-free dog food after she was having stomach sensitivities.

"It's very possible that it had a role. Nyla is part Golden Retriever and we see an increased incidence of the grain-free diet associated dilated cardiomyopathy in the Golden Retriever, but we've seen it in all breeds of dogs, small and large alike," said Dr. Rosenthal.

An uptick in cases, particularly in atypical breeds, led CVCA Cardiac Care for Pets to contact the FDA.

Studies examining a potential link
The FDA announced it was looking into the potential connection between certain diets and DCM in July of 2018. So far, they've received 300 reports of DCM. And of the nearly 200 DCM reports to the FDA in which dogs only ate one kind of diet, 90 percent of those foods were labeled grain-free.

In February, the agency provided an update on the investigation saying they've received additional DCM reports, but they have not identified specific recommendations about diet changes for dogs who are not displaying DCM symptoms. Instead they are encouraging pet owners to consult directly with their veterinarians for their animal’s dietary advice.

Other studies have also investigated the link between BEG, an acronym for boutique, exotic, and grain-free diets, and DCM.

In one study, researchers found that of the 24 Golden Retrievers who were eating BEG diets at the time DCM was diagnosed, all but 1 of the dogs showed substantial echocardiogaphic improvement after a diet change and the addition of supplemental Taurine to their diet.

Still, there are questions as to what exactly these diets include or leave out that could lead to illness.

"There have been many theories including these diets may have a deficiency in an amino acid called Taurine," said Dr. Rosenthal. "Also, most of these diets are very high in legume content: lentils, peas, chickpeas, and beans. And there's some concern that maybe those legumes might be playing a role in altering the absorption of certain nutrients in the diet or one of the theories is if there's some type of toxin in the legumes that we're unaware of. Again, we're trying to figure that out with the FDA. At this point in time, we don't know that answer."

The good news is Dr. Rosenthal is starting to see less of these cases from a few a month to one every several months. He thinks it may be due to more awareness.

The bad news is when a dog is diagnosed it's usually in the late stages of the disease.

DCM symptoms
Dr. Rosenthal recommends bringing in your pet for evaluation if they show the following symptoms:

  • Lethargic
  • Less tolerance to activity
  • Coughing or breathing problems
  • Fainting

Nyla's diagnosis has not only been emotionally taxing but also costly. In two weeks, Sheaffer said she spent $3,000 on different tests and pills, which is why she wants other pet owners to investigate the ingredients, nutritional content, and testing standards of the dog food company they choose.

"You know, this is my dog and I love my dog like I love my kids," said Sheaffer. "So, I'm going to go with she's going to be okay and hope for the best."

When Nyla was initially diagnosed, Sheaffer was told she may only have a year. However, with the change in diet and medications (five pills a day plus supplements), the Sheaffer family is hopeful Nyla's health will improve.

Sheaffer recommends anyone with questions about Taurine-deficient diets, visit

Researching dog food companies
Dr. Rosenthal also recommends feeding your pet a food that's formulated to meet Association of American Feed Control Officials (AAFCO) standards.

"At this point, we recommend using a diet that goes through aggressive feed testing, so there's certain companies that take their diets and then feed it to dogs in colonies at these nutrition sites that they make sure the diets are nutritionally adequate," said Dr. Rosenthal.

The World Small Animal Veterinary Association (WSAVA) has created a list of questions for pet owners to ask food manufacturers. See their recommendations on selecting pet foods, here.

The Pet Food Institute (PFI) has also provided a list of frequently asked questions and answers relating to the FDA's investigation. You can read more, here.

PFI sent WMAR-2 News the statement below:

As the pet food makers for many of America’s dogs and cats, PFI members are committed to the production of safe, nutritionally balanced pet food. Our member company experts, who bring decades of experience in companion animal nutrition, are collaborating closely to advance the understanding of any potential relationship between certain dog food diets and a type of canine heart disease known as dilated cardiomyopathy (DCM) in dogs not genetically pre-disposed to the condition. The U.S. Food & Drug Administration has not advised any dietary changes based on the available information. Millions of dogs are thriving on grain-free dog food every day. We remind pet owners to consult their trusted veterinarian with any questions regarding their four-legged family member’s health and well-being.
Dana Brooks, President & CEO of the Pet Food Institute

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