Skip to main content

Why Do Dogs and Cats Eat Grass? Three Theories

This is my purpose in life: to better myself through knowledge and help others do the same. I hope you enjoy my writing.

Find out why your pet may be eating grass...

Find out why your pet may be eating grass...

Several years ago, I used to wonder why our family cat always ate grass. Did the cat simply find the grass tasty, or was there a specific reason behind this habit?

In addition, I noticed our family dog doing the same thing. I never saw the cat or dog vomiting as a result of eating the grass; however, I have heard of other dog and cat owners noting that their dogs or cats vomit after eating grass.

Several studies have been carried out to determine the reasons why felines and canines eat grass. However, feline and canine experts disagree on the findings from the studies. As a result, one cannot be certain as to the real reasons. Some dog and cat owners do not agree with each other.

If cats and dogs were able to speak to us, we would know why they eat grass. In the meantime, we are left only with the theories that have been posited by the scientific community.

In this article, we will explore three theories:

  1. Learned habit—pica
  2. To purge out inedible contents
  3. Natural laxative

We will also consider whether humans can eat grass and then turn our attention to understanding how cows are able to digest this substance.

Dog eating grass.

Dog eating grass.

Theory 1: Learned Habit—Pica

This is particularly attributed to dogs. Pica can be termed as a habit of eating non-food stuff. It’s not limited to animals; it can also be present in human beings.

It might be, according to the studies, that animals have formed the habit of eating grass. They find themselves eating grass for sheer enjoyment or satisfaction. It is as if they enjoy the taste of eating grass.

Furthermore, in the case of puppies, it might be that they resort to eating grass because of boredom. In regards to this, Natural Dog Health Remedies states, “if you have a young puppy who is kept outside in the yard all day while you are at work, and he is eating grass, it is likely that he is bored.”

Some experts think dogs eat grass out of boredom.

Some experts think dogs eat grass out of boredom.

Theory 2: To Purge Out Inedible Contents

We do know cats and dogs end up eating weird things at times. In addition, when they eat their dead prey, they eat up all of the prey, sometimes including bones that might be hard to crush. When the cat eats the prey and the prey's fur, the fur might irritate the stomach and cause discomfort.

As a result of eating grass, they vomit in order to purge out the inedible content(s) in the stomach. Thus, it aids in reducing the irritation if you consider the inedible matter might end up clogging the digestive tract.

Scroll to Continue

Read More From Pethelpful

Dogs and cats lack the enzymes responsible for breaking down the cellulose, a type of fiber in grass, which can cause them to vomit the contents of the stomach.

Cats may eat grass to purge themselves of something they may have consumed but cannot digest.

Cats may eat grass to purge themselves of something they may have consumed but cannot digest.

Theory 3: Natural Laxative

Experts who base their argument in this line of thought state that the eating of grass assists in bowel movement. Thereby, it enables the indigestible matter to pass through the normal wastage passage.

As any cat owner knows, cats regularly throw up and leave lovely, wet little fur balls present around the house. But when the fur moves deep into the digestive tract, kitty needs a little help to break it down and pass it to the outer end. —PetMD

The only possible way for a cat to pass a furball, based on this theory, is by the kitty eating the grass blades.

Cat nibbling grass.

Cat nibbling grass.

Can Humans Eat Grass?

They can, but it is not recommended. It might be possible that early humans did eat grass, but nowadays, we are unable to digest the grass properly. This is because we lack the necessary enzymes to break down cellulose, a type of fiber found in grass. This is the reason why cats and dogs vomit after eating grass. They don’t have the enzymes which can process the fiber so that it can be used by the body.

Growing up, I used to chew on grass. Rarely did I eat the grass blades by swallowing them after chewing. I only chewed to derive the pleasure of sucking the grass dry of the juice contained therein. However, as noted by News24, it is not advisable to eat grass.

Grass contains a lot of silica, which is abrasive to human teeth. Grazing animals have teeth that can re-coat their own surfaces continually, so the silica does not affect them. —News 24

Cat and Dog.

Cat and Dog.

How Do Cows Digest Grass?

In contrast to humans, felines, and canines, cows have a specialized digestive system that enables them to break down the cellulose into finer pieces.

A cow has four digestive compartments. When the grass is swallowed, it is digested partially in the first and second stomach compartments then returned to the mouth. The teeth further grind the grass, whereby it’s finally broken down into finer pieces by the third and fourth compartments of the stomach.

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.


Alianess Benny Njuguna (author) from Kenya on February 07, 2018:

Hahahaha, Rydog. Yesterday at evening (February 8, 2017) I saw a dog struggling to vomit as it had eaten some grass blades. I bet it was high. Hmm...cats aren't stupid as I have lived with cats since I was young. Thanks for stopping by.

Rydog on January 12, 2018:

Hi I am a dog myself, and these accusatations are simply ruff around the edges. I eat grass to get high. Thats it. Tastes like crap but sure tickles my tail. Change this video now! Or ill send my puppy friends on you!!!!!!!!!


Mr. Bork

P.S.- Cats are stupid AF!!!!!!!! #dogos

Alianess Benny Njuguna (author) from Kenya on October 30, 2017:

That is a perfect mix.

Jeanette Harris from 11996 Valley Falls Loop Spring Hill Florida, 34609 on October 30, 2017:

I let my cat have some grass with her cat food; she would eat lots of if I let her.

Related Articles