By Pet Nanny, Kevin Kypers
I think most of us have heard the explanation that dogs eat grass when they have an upset stomach. Growing up this was easy for me to accept: my family’s dog, Tiffany, very seldom would nibble on a few blades of grass, and doing so never seemed to affect her very much. But our dog today, a Catahoula Leopard mix named Calysta, cannot get enough of the stuff. She’s been a grass connoisseur ever since she was a puppy when she would lay down in the front yard and gnaw away. I know as we approach tall grass on our morning walk she will inevitably try to dunk her head in and chomp a mouthful if I don’t stop her. If she’s eating grass simply because she has an upset stomach, I do not understand how she has displayed good health her whole life. It seems that she only vomits after she’s successfully eaten mouthfuls of grass…is she eating the grass in an effort to vomit to alleviate discomfort or is she just getting sick because of the grass?
Like any pet owner with Internet access (and probably a little too much time on their hands), I turned to Google for answers: “Why do dogs eat grass?” But the more I read the more elusive a simple answer seemed to be…
Every article seems to acknowledge the theory that dogs allegedly eat grass in an effort to cure an upset stomach. According to PetMD, “When ingested, the grass blade tickles the throat and stomach lining; this sensation, in turn, may cause the dog to vomit, especially if the grass is gulped down rather than chewed.” But—as Juliana Weiss-Roessler from Cesar’s Way acknowledges—less than 25% of dogs vomit after eating grass and only 10% display any signs of illness beforehand.
Others suggest a dog’s craving for grass is a product of evolution. Dogs’ ancestors ate every last bit of their prey, including the plant material in the stomachs of herbivores. It is true that wild canines today will eat fruits, berries, etc.—perhaps dogs eating grass is just a way of fulfilling a nutritional need? This did not seem like an adequate explanation to me…Aside from the fact that dogs do not even have the enzymes to digest grass (if something’s indigestible it’s probably not the best nutritional option), dogs who supplement this proposed dietary deficiency with fruits or vegetables are no less likely to eat grass than dogs who do not have plant matter included in their regular diet.
At least one scientific study has been performed on the subject—a 2008 study conducted at the University of California, Davis—but their research yielded little more concrete results than yes, a lot of dogs do eat grass. Researchers concluded that grass-eating was not generally associated with illness or with diet, but could be an evolutionary side effect from wild canines who regularly eat grass to purge intestinal parasites. Eating grass does not mean your dog has worms, just that they are evolutionarily predisposed to seek grass (just in case).
After all of this, I’m still not sure what to think. Eating grass does not seem to be harmful for dogs (assuming the grass was not be treated with any herbicides)—I still wish Calysta would stop chomping down grass every chance she gets. A few other theories are that it could be a sort of obsessive-compulsive disorder, or that dogs eat grass out of boredom and the remedy is to keep them more active.
Or maybe it just tastes good.
Kevin is a Peaks Pet Nanny servicing Vernon, Hamburg, Sussex, NJ