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Why Do Dogs Eat Grass. Should I Worry? [2023]

Why do dogs eat grass? Picture this… You and your favorite canine are out on your usual walk. Everything is completely normal. He or she stops to sniff a tuft of grass or other plants. You usually expect them to go to the toilet at this point.

why do dogs eat grass

But, to your surprise (or perhaps not) they start eagerly chomping down on the vegetation. Suddenly, you think, “Is this bad for my dog?”, and you quickly hurry them along.

It’s something that nearly all dog owners have encountered at one point or another. Some dogs will only eat grass occasionally, while others will greedily munch on whole mouthfuls every time they’re outside. Many doggie parents wonder, why does my dog eat grass?

Is it beneficial to them? Or could it be doing them more harm than good? Well, wonder no more! We’re going to get to the bottom of this mystery once and for all.

The reasons for dog eating grass

Eating grass seems to be a natural instinct among canines. The dog’s wild cousin, the gray wolf, regularly includes grass and various other plants in its diet. However, the most curious thing about all of this is that dogs and their wild counterparts can’t actually digest grass.

Unlike cows and sheep, canines don’t create the specialized enzymes needed to break down plant material. There is evidence to show that eating indigestible plant matter can help clear out parasites in chimpanzees, but, as we’ll see later, this doesn’t seem to be the case with dogs.

So, let’s look at the theories behind why man’s best friend eats plants that, seemingly, have no nutritional value for them.

Nutritional deficiency

One common suggestion is that dogs will eat grass when they are deficient in nutrients, especially fiber.

Pets are very good at finding the nutrients and minerals they need from other sources when they’re fed low-quality food. As well as grass, dogs may also eat dirt if they aren’t getting enough minerals. This is the most likely answer to the question, why do dogs eat grass and dirt.

There was an interesting case of a poodle that had eaten grass every day for 7 years, something that regularly made him sick. However, his owner was amazed that after only 3 days on a high-fiber diet, the dog completely stopped eating grass on walks.

Check out the 14 Best Lamb and Rice Dog Food [2020 reviews] to find a great source of nutrients for your dog.

why do dogs eat grass nutrients

Dogs eat grass when sick

Another theory is that grass-eating may act as a type of self-medication for our canine friends. Most dogs that eat grass regularly won’t be sick from it, but some do vomit afterward. Why do dogs eat grass and throw up? This is especially true for dogs that live in cities and might not get the chance to eat grass regularly. This sparked the idea that dogs may seek out grass to eat when they are feeling ill. Similar to how you or I might feel when we have an upset stomach after eating some dodgy fast food.

A 2007 study found no significant link between grass eating and illness in dogs. However, the researchers noted that some dogs ate grass and vomit when they were feeling mild gastrointestinal distress (that’s a fancy way of saying an upset stomach). This suggests that some dogs may use grass eating as self-medication. This could explain why your pooch munches on the plant when it seems to makes them sick. It could actually be helping them to feel better!

You can keep your dog’s mouth and teeth healthy by using the best dog toothpaste.

Dogs are hungry

Dogs may also eat grass because it helps them feel full. All pet owners know of at least one dog that’s always hungry. Some breeds, like Labradors and golden retrievers, are even genetically coded to eat all the time!

Once these highly food-motivated dogs learn they can eat grass, they will munch as much as they can. To them, it’s a never-ending supply of food and it likely makes them feel fuller than regular dog food because it’s indigestible. Owners of greedy dogs with a grass-eating habit should carefully limit how often their dog is allowed outside to stop them from eating too much and being sick. Make sure your dog gets high-calorie dog food when needed to gain weight.

why do dogs eat grass full

You should try it! It’s so tasty!

The final and, honestly, the most likely theory is that your dog may just simply like the taste of grass. Just like their human owners, some dogs have odd food preferences. In fact, eating wild plants such as grass is one of the less unusual dietary choices made by some domestic canines.

Owners have reported their dogs gobbling down everything from moths to bananas. My childhood spaniel would leap at the chance to eat melons and oranges. From that perspective, owning a dog that likes to eat grass suddenly doesn’t seem so unusual.

Dogs can also find cat litter an awesome snack. To avoid that dog-proof your litter box.

Is eating grass dangerous for dogs?

By now you should have a much better idea of why your dog seems to love eating grass and other plants on walks. But this still doesn’t answer the most important question; is it bad for my dog? Most vets consider grass eating to be a normal behavior that isn’t harmful in most cases. However, there are some associated risks that you, as a dog owner, should be aware of.

Dogs eating poisonous plants

The first and most dangerous risk is that your pooch could accidentally eat poisonous plants while munching on grass. There are several plants you could come across on your dog’s daily walk that could make them very sick, even if they only eat a little bit. These range from foxgloves to hyacinths and ivy to lilies (list of plants).

Luckily, toxic plants usually don’t smell very nice to your dog and they will avoid eating them. But owners with especially greedy dogs should be extra careful about what plants they come across. Learning the common, poisonous plants found in your area and how to identify them is an essential skill for every dog owner.

Check out these dog training books to teach your dog when it’s not OK to eat grass.

Toxic chemicals

In some cases, the grass your dog is eating may have dangerous chemicals sprayed on them, such as weed killers and pesticides. If you’re walking your favorite canine through farmland or near people’s gardens, it’s best to stop them from eating grass just in case they ingest a toxic chemical.

Instead, only let them eat grass in public parks. Even better yet, restrict grass-eating to your own garden where you know it’s 100% safe. Here you can find some of the dog-friendly plants for your garden. If your dog shows signs of poisoning, such as vomiting and diarrhea, after eating vegetation you should bring them to your vet immediately to be treated.

Use a dog harness, then you can pull your dog away from hazardous places without the risk of injury.


Another issue with grass-eating is that it puts your dog at a higher risk of picking up parasites like hookworms and roundworms. This happens when the dog swallows the eggs of these worms that are left on the grass from other dogs and wild animals. Therefore, your pooch might be more at risk if they like to pick at the vegetation in their local park, where many other dogs are around.

Thankfully, this generally doesn’t pose a problem to most dogs and can be easily solved by keeping your dog on a regular worming schedule. If your canine friend likes to eat grass daily, it might be a good idea to have a chat with your vet about putting them on a more frequent worming dose.

As we’ve seen earlier, some dogs become sick and vomit every time they eat grass. This usually isn’t an issue if it only happens occasionally, but dogs that vomit regularly because of grass eating might run into health problems down the line. As you can imagine, they would be very uncomfortable due to having an upset stomach on a daily basis.

However, if this continues for a long time, they could potentially become severely malnourished and underweight because their bodies aren’t given the chance to properly digest their food. Here, you should always stop your dog from eating grass on walks and supervise them when they’re outside.

What’s the bottom line?

That was a lot of information coming from one simple question! Why is my dog eating grass? You’re probably wondering by now, what are the right answers? As we’ve seen, dogs eat grass for a variety of reasons. Some could have a more severe underlying cause, but most pups just eat grass because they like it.

If you’re concerned about your dog’s habit, the best advice is to speak to your vet about it. They can help you evaluate your pooch’s diet for missing nutrients that may be driving them to eat grass or may recommend a food that will make your dog feel full for longer.

However, the bottom line of all this is, as long as your grass munching pup has access to a safe source of vegetation that doesn’t make them sick and they’re on a regular worming schedule, grass-eating is often completely harmless and normal.

Author: Victoria Molloy – Victoria Molloy developed a love for animals at a young age, driving her to pursue a career in animal science. She has recently graduated with a B.Sc. in Zoology, which has given her an appreciation for animals of all shapes and sizes. Currently, the owner of one dog, three cats, a pony, and a horse; Victoria seeks to educate and entertain her fellow pet owners and animal lovers around the world.

Cover image by Stefan Stefancik


This Post Has 2 Comments

  1. Frank

    Thank you for the article. My dog eats grass all the time. He definitely has enough to eat at home, but grass seems to be his favorite food item. I think it’s mostly OK for the dog to eat grass, but now I know to watch out for potentially dangerous plants.

    1. Priit Kallas

      Thank you for sharing your experience! For most dogs eating regular grass is just fine. Poisonous plants may become a problem sometimes. Find out about those in your area. Another problem might be dust and exhaust from the cars. Try to keep your dog from eating grass in the areas where there’s a lot of traffic.

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