For the past two years, the FDA has been investigating a strange development in dog health. The agency started hearing reports that more pups than usual were developing a condition called dilated cardiomyopathy, which causes the heart to weaken and grow larger.
Typically, veterinarians see this issue in large dogs. Some breeds, such as Doberman pinschers, great Danes and others, are genetically predisposed to the condition, which slowly saps the heart of its ability to efficiently pump blood. This can lead to fainting, weakness or death. But recently, dogs that aren’t considered at risk of the heart disease, like golden retrievers, started showing up to veterinarian offices with enlarged hearts. Veterinarian providers began talking amongst themselves and observed that some of these dogs were eating “grain-free” food — kibble and soft canned food formulated without corn, wheat and soy. It begs the question: Could these heart troubles stem from a dog’s diet?
That’s what prompted the FDA and other research groups to investigate the health effects of grain-free dog food. For the most part, researchers have a lot to learn about this supposed relationship, which is a familiar situation for the profession. “All of us that are in this from an academic standpoint are the first to admit that nutrition of dogs and cats is woefully behind that of other animal species and humans,” says Greg Aldrich, a pet nutritionist at Kansas State University. The more investigators learn, the closer they come to gaining broader understandings about what keeps our pets healthy.
Pet Food Fads
A stroll through the ever-expanding pet care aisle could leave any owner confused about what food to buy. A few decades ago, this might not have been the case. That’s when grain-free varieties first emerged, and the products took up little shelf space. This type of dog food appeared, in part, because some breeders and owners concluded that commodity foods like soy and other grains must somehow be lower quality, Aldrich says. The science doesn’t back up that idea. But that didn’t stop the product from taking off. “It emerged from nothing to a prominent part of the marketplace,” Aldrich says.
To replace starches in grain-free kibble, companies introduced substitutions like sweet potatoes, lentils and legumes. But these “new” ingredients could leave dogs with low levels of an essential protein building block called taurine. Legumes might not be an adequate source of two precursor nutrients that dogs’ bodies rely on to make taurine. To add to that, it’s also possible that these alternative starches can ferment in dogs’ intestines and may foster taurine-degrading microbes — creating a one-two punch of nutrient deprivation. Several grain-free formulas also throw in more unusual or exotic protein sources, like lamb, duck and kangaroo — all of which might provide less taurine, or make the precursor nutrients less effective.
These possibilities are just that —…