Why Do Dogs and Cats Eat Grass?

Written by: Richard Rowlands, Pet Health Expert

Does your dog or cat eat grass? And have you ever wondered what's behind the behavior? In this article, we'll take a look at a few of the reasons why dogs and cats eat grass. We'll also explore whether or not you should be worried about them grazing on your lawn.

Scientists can't agree on a single reason for dogs and cats eating grass. But several theories have been put forward to explain it. It may simply be the case that different animals eat grass for different reasons. Let's take a look at some possible answers.

Main Reasons


If your pet is full of energy but they're not getting enough mental or physical stimulation to keep them active, they may resort to eating grass out of boredom. If this continues for long, it can become a habitual action.

To Relieve an Upset Stomach

Research conducted by a group of scientists headed by Professor Benjamin L. Hart at the University of California, Davis, School of Veterinary Medicine found that out of 47 dog owners whose dogs ate grass frequently, 4 confirmed that their dogs showed signs of illness before the action, and 6 dogs were said to have vomited after.

In a larger online survey targeted at 3,000 dog owners (with 1,571 relevant results) 8% of dog owners claimed that their dogs showed signs of illness before eating grass, and 22% reported that their dogs vomited afterwards. These results could mean that dogs eat grass to relieve an upset stomach. Some scientists believe that the grass blades tickle the walls of the gut, inducing vomiting.

If an upset stomach is suspected, work with your holistic veterinarian to analyze your pet's diet and look for natural, more nutrition options. Cold pressed diets for dogs have been shown to digest faster and lessen stomach upsets and bloating.

To Eliminate Intestinal Parasites

According to Dr. Benjamin L. Hart, dogs and cats have an ancestral history of eating plants. Plant remains have been found in 2% - 74% of scats and stomach content samples of wild canids and felids. This may point to a biological purpose for plant eating. One theory is that dogs and cats eat plants to purge themselves of intestinal parasites. This could explain why younger dogs that are most susceptible to parasites tend to eat grass more often than older dogs.

Nutritional Deficiencies

Plants contain cellulose, fiber, and certain enzymes that can be beneficial for pets. For this reason, some scientists believe that pets eat grass when they lack fiber, minerals, or enzymes in their diet. To aid rapid digestion of food and improve gut health, they may resort to plant eating.

Is It Safe for Dogs and Cats to Eat Grass?

Eating grass is a normal behavior for dogs and cats, but it's vital to ensure they stay away from grass that's been treated with pesticides, herbicides, or fertilizers. When ingested, these chemicals are highly toxic and can be potentially fatal for pets. If you need to treat your yard for fleas, ticks, and other insects, consider using a natural alternative.

It is also possible for dogs and cats to ingest parasites while feeding on grass. This can lead to a great deal of discomfort and a number of serious health conditions. Please visit your veterinarian immediately if your pet displays potential symptoms of parasitic infection such as bloody urine or vomit, diarrhea, or weight loss.

How to Stop Your Pet from Eating Grass

So far in this article, we've explained why eating grass is normal for dogs and cats. We’ve also highlighted some of the potential dangers associated with the behavior. In this final section, we'll take a look at a few ways to stop your pet from eating too much grass.


With a little patience, it's possible to train your pet to stop eating grass. Start off by supervising your pet every time that they are outside. If they attempt to eat grass, gently discourage them with a verbal command like "leave it". To speed up the process, praise your pet and give them a treat each time they respond to your command.

Mental and Physical Stimulation

Engaging your pet mentally and physically is one of the best ways to discourage unwanted behaviors like eating grass. Stimulate your pet by giving them plenty of attention and playing with them regularly. It's also a good idea to provide them with a variety of toys.

Feed Healthy Plants

We recommend feeding your pet fresh fruits and vegetables to make up for any nutritional deficiencies in their diet. Superfoods like kale, spinach, blueberries, coconut oil, and pumpkin help promote overall health and support the digestive system. Fresh fruits and vegetables are also a great source of fiber, minerals, and enzymes which may be lacking in your pet's diet.

If your pet doesn't like freshly prepared fruits and veggies, there are a number of great food toppers that can add nutrients (and flavor!) to your pet's ordinary food.

Regular Vet Visits

Regular vet visits for your dog or cat is the best way to diagnose, prevent and treat parasitic infection. Your vet my recommend deworming to reduce irritation in your pet's gut and prevent them from eating grass to purge their digestive tract (also known as herbal prophylaxis). For more information about deworming your pet, please consult with your veterinarian.

As we've highlighted throughout this article, eating grass is a normal behavior for dogs and cats. What's more, it may actually benefit their health. For this reason, some pet owners find it useful to provide a safe way for their pet to eat grass. The best way to do this is by growing grass in a container for them to enjoy. We recommend keeping the container inside your home to ensure it stays free from chemicals and parasites.

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