A recent increase in dilated cardiomyopathy, or heart disease, in dogs and cats is currently under the microscope as the Food and Drug Administration determines whether a link exists between grain-free pet food and DCM.
The FDA conducted a study in July 2018 related to certain diets and their association with heart disease. The study was completed in early 2019 and the results were released stating “the agency believes that the potential association between diet and DCM in dogs is a complex scientific issue that may involve multiple factors.”
The FDA had been receiving various reports of animals diagnosed with heart disease after being fed pet foods containing large proportions of peas, lentils, legume seeds and potatoes in various forms. DCM has a genetic predisposition to certain large dog breeds such as Doberman Pinchers, Great Danes and Irish Wolfhounds. It is not commonly diagnosed in small and medium sized breeds. However, the FDA’s DCM case reports have included breeds from all over the spectrum including Bulldogs, Golden Retrievers, Boxers, Shih Tzus and Australian Shepherds.
Ryan Baumwart, DVM, DACVIM (cardiology) and staff member at the Oklahoma State University Center for Veterinary Health Sciences, says the recent uptick in cases of DCM are a concern for his field and he hopes the FDA will continue to look for the cause in these cases.
“I think the FDA’s release of information does bring up the concern of diets being related to cases of DCM,” he said. “I do not think we currently know if there is a problem with the diet being deficient in grains or if it’s the substitutes used, or if the protein is even involved in the issue.”
Kicking grains to the curb
The suggestion that grain-free diets could be causing more harm than good forces us to look at why grain-free diets were originally pushed as a healthier option. Grains were given a bad rap in the pet industry and their absence in the pet food manufacturing has hurt the grain sector of the agriculture industry. Grain-free became a fad in some ways, and Baumwart says it was likely because of a concern toward removing grains from human diets for the purpose of allergies and intolerances that prompted a change in ingredients for dog foods.
“There has been some translational concern that dogs could have similar intolerances to grains,” Baumwart added.
However Lisa M. Freeman, DVM, Ph.D., DACVN, has stated food allergies in pets are extremely uncommon and in fact grains do not contribute to any health problems and are a valuable source of protein, vitamins and minerals. She says the grain-free diet fad is more a marketing tool to get pet owners to buy what they believe is a better product although no proof exists. Freeman stated small pet food manufacturers might be better at marketing than at nutrition and quality control.
Freeman has also suggested the heart disease issue could be caused by a combination of exotic meats, fruits and vegetables used to replace more traditional ingredients in pet food.
Although the connection between grain-free diets and DCM is yet to be deciphered, many pet owners are left wondering what they should be feeding their best friends in the meantime.
“I am telling pet owners that we currently do not know the significance of grain-free diets and their association with DCM,” Baumwart said. “There is enough concern that I think we should probably use a diet that includes a grain until this issue is better understood. I hope that if conclusive evidence indicates that certain diet—with or without grains—increases the risk of DCM, pet food companies would avoid those ingredients or combination of ingredients.”
