Grain-free dog food and heart disease (DCM): what the FDA found

In July 2018 the FDA announced it was looking into reports of dilated cardiomyopathy (DCM), a disease of the heart muscle, in dogs eating certain foods. Many of the foods were labeled grain-free. The news changed how a lot of people shop, but what the FDA actually found is more limited than the headlines suggested.

What the FDA investigated

DCM makes the heart muscle weak and the heart enlarged. It's usually seen in breeds with a genetic tendency, such as Dobermans, Great Danes and Boxers. The FDA's concern was cases in breeds not usually prone to it. The reports it received mostly involved foods with a high proportion of peas, lentils, other legume seeds (pulses) and potatoes among the first ten ingredients.

• Reports: from January 2014 to April 2019 the FDA received 524 DCM reports (515 dogs and 9 cats). They covered 560 dogs, of which 119 died.
• The foods: 91% of the reported diets were grain-free, 93% contained peas and/or lentils, and 42% contained potatoes or sweet potatoes.
• Nutrient testing: FDA lab testing found grain-free and grain-containing foods had similar average protein, fat, taurine and other amino acid levels.

Where it stands now

In December 2022 the FDA said it doesn't intend to release further public updates "until there is meaningful new scientific information to share." It also said that the reports alone "do not supply sufficient data to establish a causal relationship" with the products named. The FDA calls the possible link "a complex scientific issue that may involve multiple factors," and research by universities and industry is ongoing.

The FDA never told owners to stop feeding grain-free food, and it hasn't recalled any food over DCM. Its advice is to work with your vet, who may consult a board-certified veterinary nutritionist, before changing your dog's diet.

What this means when you're choosing a food

• Grain-free isn't healthier by default. Most dogs digest grains fine, and unless your vet has diagnosed a grain allergy, there's no need to avoid them.
• If you feed grain-free, look at the first ingredients. The FDA's concern centers on foods where peas, lentils or potatoes make up a big part of the recipe.
• Look at the maker, not just the recipe. WSAVA's questions about qualified nutritionists and feeding trials are a good filter. See our WSAVA guide.
• Watch for signs. Contact your vet if your dog has less energy than usual, coughs, breathes with difficulty or collapses.

Grain-free foods we grade

These grain-free formulas are among the best-sellers we grade. Grades don't mark them down for being grain-free, because the FDA hasn't found a cause. They're scored on recalls, the maker's WSAVA answers, owner ratings and value like every other food.

• Merrick Grain-Free Real Texas Beef Dinner: grade B (75/100)
• Purina ONE Chicken Recipe Pâté Grain-Free: grade B (75/100)
• Merrick Real Texas Beef + Sweet Potato Grain-Free: grade C (74/100)
• Instinct Original Real Chicken Recipe Grain-Free: grade C (66/100)
• Instinct Original Grain-Free Real Chicken Recipe: grade D (63/100)
• Taste of the Wild High Prairie Grain-Free Roasted Bison & Venison: grade D (58/100)
• Instinct Original Grain-Free Pâté Variety Pack: grade F (53/100)
• Wellness Complete Health Grain-Free Indoor Deboned Chicken: grade F (46/100)

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