Grain Free Diets and Heart Disease

The pet food business is big these days, as you can tell from the amount of advertising that you see regarding pet foods.  But just like anything else, some of that marketing is hype, without any science behind it.  One example of that is “grain-free” diets.  The way they are being marketed, you might think there is something terrible about feeding grains.  But the truth is for most dogs grains are perfectly fine and appropriate.  In fact, the Food and Drug Administration (FDA) is warning consumers to be cautious about feeding grain-free diets due to concerns that they could lead to cardiomyopathy (a type of heart disease) in your dog.

Let’s start by learning what a grain free diet is.  Any diet made without wheat, corn, rice and other grains is considered “grain free.”  Any dry dog food must have some kind of starch in order to make it into kibble.  So with grain-free diets, they just substitute potatoes or peas or some other kind of starch.

According to a warning on the FDA web site, they are investigating a potential dietary link between canine dilated cardiomyopathy (DCM) and dogs eating certain grain-free dog foods. The foods of concern are those containing legumes such as peas or lentils, other legume seeds, or potatoes listed as primary ingredients. The FDA began investigating this matter after it received reports of DCM in dogs that had been eating these diets for a period of months to years. DCM itself is not considered rare in dogs, but these reports are unusual because the disease occurred in breeds of dogs not typically prone to the disease.

Between January 1, 2014 and April 30, 2019, the FDA received 524 reports of DCM (515 dogs, 9 cats), and most reports were submitted after the FDA’s first public alert in July 2018. The total number of pets affected is greater than 524 because some reports included multi-pet households.  This provoked the FDA to issue its warning.

What is Canine Heart Disease or Dilated Cardiomyopathy (DCM)?

Dilated cardiomyopathy (DCM) is a type of canine heart disease that affects the heart muscle. The hearts of dogs with DCM have a decreased ability to pump blood, which often results in congestive heart failure.

Some breeds, especially large and giant breeds, have a predisposition to DCM. These breeds include Doberman Pinschers, Great Danes, Newfoundlands, Irish Wolfhounds, and Saint Bernards. While DCM is less common in medium and small breeds, English and American Cocker Spaniels are also predisposed to this condition.

The reports submitted to the FDA span a wide range of breeds, including many without a known genetic predisposition. When early reports from the veterinary cardiology community indicated that recent, atypical cases in breeds like Golden Retrievers, Labrador Retrievers, Whippets, Bulldogs, and Shih Tzus all consistently ate grain alternatives in their diets, the FDA took notice.

The FDA’s July 2019 update includes the names of dog food brands that were named 10 times or more in reports submitted through April 30, 2019. Most reports were for dry dog food, but raw, semi-moist and wet foods were all represented.

  • Acana (67 reports)
  • Zignature (64 reports)
  • Taste of the Wild (53 reports)
  • 4Health (32 reports)
  • Earthborn Holistic (32 reports)
  • Blue Buffalo (31 reports)
  • Nature’s Domain (29 reports)
  • Fromm (24 reports)
  • Merrick (16 reports)
  • California Natural (15 reports)
  • Natural Balance (15 reports)
  • Orijen (12 reports)
  • Nature’s Variety (10 reports)
  • Nutrisource (10 reports)
  • Nutro (10 reports)
  • Rachael Ray Nutrish (10 reports)

It is easy to panic anytime we see an FDA headline about pet food. After all, keeping our dogs healthy is essential to us, and we know that diet can make a big difference in a dog’s well-being.   As a general rule of thumb, the best thing you can do for your dog’s dietary health is to consult your veterinarian.  However, as a general rule, we do not recommend feeding grain-free diets unless your pet has a documented allergy to grains. Together we can weigh the pros and cons of your dog’s diet and, if necessary, monitor your dog for signs of DCM.

If a dog is showing possible signs of DCM or other heart conditions, such as decreased energy, cough, difficulty breathing and episodes of collapse, you should contact your veterinarian as soon as possible.