Why do Dogs Eat Grass?

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Why do dogs eat grass? There are many theories about why your dog might be eating grass. First and foremost, you have to understand that eating grass is actually an incredibly common behavior across all dog breeds.

So, why do dogs eat grass? Dogs eat grass for one of these four reasons:

  1. Eating grass is instinctual
  2. Nutritional deficiencies
  3. To induce vomiting
  4. They simply want to eat grass

No one can really seem to agree on why dogs eat grass, but luckily for you..

There is some new scientific literature out there that seems to point in the right direction. Keep reading and we’ll help you get to the bottom of it. It’s more exciting than watching grass grow.

Pinky promise. 🙂

Why do dogs eat grass?

Are you a Star Wars fan?


What are you, incapable of emotion?

Unable to see?

Well, for the rest of us normal folk who sometimes fantasize about taking a ride on the Millennium Falcon (with 1970’s Harrison Ford…preferably a shirtless 1970’s Harrison Ford), you may remember those cute (but surprisingly violent) teddy bears that inhabited the forest moon of Endor in the Star Wars universe.

That’s right, I’m talking about Ewoks.

So, imagine living with one of those little guys.

You would wake up to your very own living teddy bear that would cheer you on while you made breakfast, give you hugs for doing the laundry, and massacre storm troopers after dinner (maybe not that last part).

Well, I personally have my own incredibly cute Ewok look-alike in the form of a spunky, energetic dog named Happy.

One look from this little guy and you’ll be mopping up the puddle of melted heart juice on your floor.

He’s a stunner and not to brag (but actually yes, to brag), he might even be more handsome than some people.

He’s a playful pup by day and intense snuggler at night. He’s what most women look for in a human man. He is the apex in all of dogdom in my eyes. Every moment spent with him is a moment of joy.

But there’s one thing about Happy that doesn’t quite fit with the rest of the picture: he’s addicted to grass.

No, not the “grass” that college students everywhere celebrate the existence of every day at 4:20, but the literal green blades beneath our feet.

Where you see uniform greenness that needs to be annoyingly trimmed every Saturday, my little guy sees a succulent, five-star feast.

I can bring him to a dog park full of incredibly playful dogs with other owners practically throwing treats in his general direction and he’ll choose to all-out bolt straight for the most luscious patch of grass.

He’ll plant himself there, ferociously gnawing on the blades while he rolls around in the glory that is his thick patch of grass.

After a few minutes he’ll get his fill and start noticing other living things and eventually he’ll leave in pursuit of a playmate.

I wish that was the end of it, but wait, there’s more!

The day after Happy feasts, you’ll most likely find me stooped down to his level just off the sidewalk pulling the poo out of his butt because the poorly digested grass is hanging on for dear life.

No, I’m not joking.

Of course, I use a poo bag to perform this most unsavory of tasks, but it still gives me the heebie-jeebies.

To make matters worse, he likes to watch to make sure I’m doing things correctly back there.

Oh, the things they don’t tell you about dog ownership…

“Oh, by the way, you may occasionally have to pull your dog’s shit out of him while you maintain steady eye contact. So if you could just sign here to complete the adoption…”

But for all that is kind and holy in the world, why? Why does my dog eat grass? Why must I be confined to a life of poop extraction?

Out of disgust and a legitimate fear for my dog’s general health, I did some investigating of my own. So let me share what I learned with you about the relationship between grass and your dog before we get into the theories behind this strange and unsavory habit.

Can Dogs Eat Grass?

Short answer: Yes.

Dogs have the ability to consume and digest some plant material (albeit a bit poorly), so there’s no need for panic when you first notice your pal tucking in on some of those fresh greens.

It’s more than safe for a dog to eat grass.

But, you do have to be careful about treated grass.

Unfortunately, we live in an age where a manicured lawn is so important that even people in the middle of the desert waste precious water to make sure their grass is healthier than the neighbors.

What a backwards way of thinking.

Because of this high value people place on their pathetic patches of green stuff, it’s common for them to treat their lawns with some form of chemical, whether it be a weed-killer or insecticide.

Grass that has been treated with any kind of chemical could potentially poison your dog if ingested.

Even if your dog isn’t a grass eater, it’s good practice to avoid using these chemicals. Your dog can pick them up on his or her paws and lick them off later during a relaxing grooming sesh.

Seriously, stop treating your lawns.

Plant some plants that are native to your area and create your own little ecosystem. Screw what the neighbors think of you. Feel satisfied with the notion that they’re killing polar bears while you’re saving the environment.

(But for the Love of God) Why is My Dog Eating Grass?

Let’s take a look at the main competing theories and separate fact from fiction.

Why do Dogs Eat Grass Theory #1: Take a Ride on the Vomit Comet

Perhaps the most popular and talked about theories behind why our dogs eat grass is the idea that it’s used to induce vomiting.

This has been a standard explanation for a long time, however new scientific evidence has come to light that suggests quite the opposite.

In a study conducted by veterinarians and scientists from the University of California at Davis, they found that of 1,571 dogs that ate grass, only 22% commonly threw up after doing so. Of those dogs prone to vomiting, it was reported that they appeared physically ill before eating grass.

So what does this tell us?

Well, firstly, it tells us that there is a good possibility that some dogs do indeed eat grass to induce vomiting. However, 78% of the dogs analyzed in the study did not throw up after eating grass.

How do you explain that?

As a side note, let this be a lesson to all those researching the Internet for answers:

Where possible, look for scientific studies that have been done on the topic before consulting some soccer-mom’s article on a random website or some self-proclaimed dog guru’s blog.

I am neither, so you should definitely trust strangers like me on the Internet.


Why do Dogs Eat Grass Theory #2: Nutritional Deficiencies, Yo

Some have argued that dogs munch on grass to obtain vitamins and nutrients that they aren’t getting from their daily diet.

In the same study mentioned above, they looked at this hypothesis and broke it wide open.

They found that dogs who consumed a diet supplemented by plant and vegetable material ate grass as often as those who had no plant material in their diet.

There was no correlation between what the dog ate on a regular basis and whether or not they ate grass.

Hmm, interesting. Go on…

Why do Dogs Eat Grass Theory #3: Instincts, Bro

An interesting theory brought up by these scientists relates domestic dog grass eating behavior with those of a more wild variety.

Wolves and other wild dogs have been known to consume grass and other plant material, both through the stomachs of their prey and straight from the source. The amount of grass and plant material eaten varies between species, but they’re still finding the stuff in their poo.

(Side note, just think about the fact that scientists were running around in the wilderness, searching for wolf shit, dissecting it, and spending years thinking about it and writing papers about it. If that’s not dedication, I don’t know what is.)

Oftentimes they would find intestinal worms and other parasites wrapped around individual blades of grass, suggesting that the animal consumed the grass as a MacGyver way of scouring out those little bastards.

They go on to suggest that perhaps our domestic dogs have inherited this instinctual habit from their ancestors, despite the fact that most domestic dogs are worm and parasite free.

It could be something that’s just ingrained in their brains.

Why do Dogs Eat Grass Theory #4: Ain’t Nuthin’ to it but to do it

The last and most unsatisfying explanation as to why dogs eat grass is that they just f*cking want to.

They might like the texture or taste of those soft blades of grass, or perhaps they enjoy the action of ripping it out with their mouths.

Or maybe it’s their way of saying, 

“You don’t control me! Watch me eat it! WATCH ME.”

– Your dog

Or not.

Maybe a dog eating grass is the dog equivalent of a person eating kale. Some (weirdos) eat it because it has purported health benefits while others eat it to throw up, because let’s be honest, it tastes like shit.


As long as you don’t treat your grass with some unholy, incredibly toxic chemical, your dog will be A-OK after eating it.

If that’s okay with you, you can just leave it at that.

For the rest of us seeking out logic and order in this chaotic world, we’re desperate to know why our dogs do this.

Unfortunately for us, there isn’t one air-tight explanation for this behavior.

We have to live with the uncertainty that our dogs might be eating grass to puke, because his wolf-brain tells him to, or just because he likes the taste and enjoys when you pull grass from his ass.

For my little Ewok, I’ve settled on that fact that he mostly eats grass for pleasure and maybe because something in his brain is telling him to.

He has never puked after downing a plate-full of green gold and he doesn’t have any parasites.

So for now, I’ll let him keep munching on those thick tufts of grass and extracting them from his backside because I want him to be happy.

If a patch of grass does the job, who am I to deny him of it?

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