Why Do Dogs Eat Grass?

Dog eating grass

There are several theories about why dogs might graze on grass, like making up for a dietary deficiency, to help induce vomiting, to introduce more fiber into their diet or simply because they like the taste and texture.  

Though dogs and humans have a great bond, sometimes dogs do things we find puzzling, like when we ask ourselves, “why is my dog eating grass?” The good news is a dog eating grass or dirt on occasion is nothing to worry about. This is not uncommon behavior, even though it may seem a little strange. 

Though a dog or puppy eating grass is common, there isn’t much evidence to tell us why they do it. Behaviorists and veterinarians have been perplexed by the behavior for decades, but some of their theories include the following.  

Why Is My Dog Eating Grass?

Self Medicating 

Probably the most common answer to, “why does my dog eat grass?” is because they have an upset stomach. It is a widely held belief amongst dog owners that if a dog feels nauseous, they’ll eat grass to induce vomiting.  

This belief, however, still only remains a theory. In fact, it’s quite unusual for dogs to vomit after eating grass, with less than 25 percent doing so and only a further 10 percent displaying signs of illness beforehand.  

They Like the Taste of It

Another reason why dogs eat grass could be because they like the taste of it. Dogs are descended from wolves and as such, they are natural omnivores—meaning they might be grazing in your backyard to forage.  

Nutritional Deficiencies

Some veterinarians have suggested dogs might eat grass to make up for nutritional deficiencies in their diet. Though there has been some evidence to support the theory that dogs eat grass because they need more fiber in their diet, more studies need to be done before this can be considered fact.  

Nonetheless, if you’re concerned your dog may be eating grass because they’re not getting the nutrients they need, talk to your veterinarian about making sure they’re eating a complete and balanced dog food


When dogs are understimulated, they may engage in behaviors to alleviate their boredom. These behaviors can include digging, excessive chewing and eating grass, among others. That’s why it’s essential to keep your dog both physically and mentally stimulated.  

Make sure you’re giving your dog ample opportunity to exercise and get them toys to play with when in the yard. Puzzle games and other enrichment activities will help keep your dog happy, healthy and less inclined to engage in problematic behaviors. 

Dogs Might Need Grass in Their Diet

Another explanation for why dogs eat grass could be related to how they’ve evolved. This theory relates to the fact that wild canids eat all of an animal when they catch it. The animals that wild canids—your dog’s ancestors—would catch and eat were usually herbivores. This means when wild canids ate these animals, they might also have eaten a lot of grass and plants in the intestines of their prey.  

Wild canids, such as foxes, are known to eat certain berries and other plant material, supporting the idea that dogs eat grass because it’s an inherited behavior.  

Why Do Dogs Eat Dirt?

Though less common than eating grass, dogs will sometimes eat dirt. Occasionally when your dog has been munching on grass, you’ll notice they might sample a bit of the soil as well. Why do dogs eat dirt? Is it for the same reasons that cause them to eat grass?  

Mineral Deficiencies

Dirt contains minerals, so when you see them licking or nipping at the ground, they may be trying to supplement their diet with minerals they may be lacking. Talk with your veterinarian to see if changing your dog’s food or giving a supplement can help.  

They Might Be Digging

Although it may look like your dog is eating dirt, they might just be digging in it with their snout. If your dog smells something tasty in the soil, they’ll use their nose to aid with the digging and to help locate the item in question. If they’re doing this in your yard or back garden, they may be hunting for their own buried treasure.  

Is it Okay for My Dog to Eat Grass & Dirt?

Grass eating is normal behavior for dogs and it’s not a concern unless they’re doing it excessively or it’s a sudden change in their behavior. If they start ingesting a lot and don’t seem to be their usual selves or are repeatedly eating grass and vomiting over a period of a few hours, it’s time to contact your veterinarian.  

If you are still concerned about your dog eating grass, discuss it with your veterinarian, just in case, so they can check your dog and rule out any possible health concerns.  

Discover more insights into dog behavior and more from our experts on our Pet Expertise page. 

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