Pet Foods Potentially Linked to Heart Disease in Dogs and Cats

Federal regulators continue to investigate an increase of dilated cardiomyopathy cases in dogs and cats fed pet foods containing peas, lentils and potatoes.

The U.S. Food and Drug Administration began an investigation in July 2018 after increased reports of canine dilated cardiomyopathy occurring in dog breeds not typically genetically prone to the disease. Dogs in those reports had been fed pet foods containing peas, lentils, other legume seeds, or potatoes as main ingredients, leading veterinarians, researchers and the FDA to suspect a link between diet and DCM.

During the last decade many pet food manufacturers have included these plant proteins in their formulations. They are cheaper than quality animal protein sources and enabled manufacturers to capitalize on the grain free pet food trend.

Canine DCM is a disease of a dog’s heart muscle and results in inefficiency to pump blood and an enlarged heart. Dogs with heart disease may show signs such as decreased energy, cough, difficulty breathing and episodes of collapse.

In an update from the FDA on June 27, 2019, the agency released initial results of its investigation, but stopped short of declaring a link between DCM and certain pet food ingredients or issuing any pet food recall.

“Based on the data collected and analyzed thus far, the agency believes that the potential association between diet and DCM in dogs is a complex scientific issue that may involve multiple factors,” the agency said.

Between January 1, 2014 and April 30, 2019, the FDA received 524 reports of involving 560 dogs and 14 cats diagnosed with DCM. Some reports included multiple pets in the same household. Of those reported, 119 dogs and 5 cats died.

The majority of reports were submitted after the agency announced its investigation to the public about the potential link between pet food ingredients and DCM in July 2018. The FDA said there were many other reports of non-DCM heart disease and cardiac symptoms in pets submitted during that time, but the agency only included those with a confirmed DCM diagnosis in its report. The true number of cases may be underreported because animals are typically treated symptomatically, and diagnostic testing and treatment can be complex and costly to owners.

Predominant dog breeds developing DCM in those reports were Golden Retrievers, mixed breeds, Labrador Retrievers, Great Danes, Pit Bulls, German Shepherds, Doberman Pinschers and Australian Shepherds. The FDA said the prevalence of reports involving Golden Retrievers was due to breed-specific social media groups and activities that raised awareness of the issue in these communities and urged owners and vets to submit reports to FDA.

“We understand the concern that pet owners have about these reports: the illnesses can be severe, even fatal, and many cases report eating “grain-free” labeled pet food,” the agency said. “The FDA is using a range of science-based investigative tools as it strives to learn more about this emergence of DCM and its potential link to certain diets or ingredients.”

Most of the reports were of dogs fed a dry dog food, but not all. 91% were labeled grain free. 93% contained peas and/or lentils. 42% contained potatoes/sweet potatoes.

Brands and varieties of dog food varied widely. Brands named most frequently in reports submitted to the FDA included Acana (67), Zignature (64), Taste of the Wild (53), 4Health (32), Earthborn Holistic (32), Blue Buffalo (31), Nature’s Domain (29), Fromm (24), Merrick (16), California Natural (15), Natural Balance (15), Orijen (12), Nature’s Variety (11), NutriSource (10), Nutro (10), and Rachael Ray Nutrish (10). These include both grain-free and grain-containing diets in all forms (kibble, canned, raw, home-cooked).

Animal protein sources in the reported diets also varied widely, and many diets contained more than one protein source. The most common animal proteins in the reported diets were chicken, lamb and fish. However, some diets contained novel protein sources such as kangaroo, bison or duck. No one animal protein source was predominant. The common thread appears to be legumes, pulses (seeds of legumes), and/or potatoes as main ingredients in the food.

See a list of all reports of dilated cardiomyopathy in dogs and cats reported to the FDA between January 1, 2014 and April 30, 2019.

According to and article published December 2018 in the Journal of the American Veterinary Medical Association entitled “Diet-associated dilated cardiomyopathy in dogs: what do we know?”, in addition to those dogs with DCM completely unrelated to diet, there may be two groups of dogs with diet-associated DCM: dogs with DCM specifically related to taurine deficiency and dogs with DCM associated with separate, but yet unknown, dietary factors. Study authors recommended that if DCM is diagnosed in a dog that is eating a boutique brand pet food, vegetarian, vegan, or home-prepared diet, veterinarians should measure plasma and whole blood taurine concentrations. Authors also recommended that all other dogs in the household that are eating the same diet be screened for DCM. Read the FDA’s updated information for veterinarians.

FDA has not issued a Pet Food Recall

“The FDA has not yet determined the nature of the possible connection between these foods and canine DCM, so we do not have definitive information indicating that the food needs to be removed from the market,” says the agency. “We have shared case report information with these firms so they can make informed decisions about the marketing and formulation of their products. We are also sharing this information with the public, but encourage pet owners to work with their veterinarians, who may consult with a board-certified veterinary nutritionist, prior to making diet changes.”

The FDA advised pet owners to contact their veterinarian if their dog is showing possible signs of DCM or other heart conditions, including decreased energy, cough, difficulty breathing and episodes of collapse. Provide a dietary history of food and treats fed to the pet.

Until more is known, pet owners may want to check pet food ingredient labels for legumes such as peas, beans, lentils, chickpeas, soybeans and peanuts; or potatoes and sweet potatoes; and make their own determination of the risk of feeding such foods. Consumers with questions may visit the FAQ page.

The agency said it will continue to to investigate and gather more information in an effort to identify whether there is a specific dietary link to development of DCM and will provide updates to the public as information develops. Consumers and veterinarians are encouraged to submit well-documented DCM cases using the Safety Reporting Portal.

See a list of the best dog food without peas, legumes or potatoes.