Why Do Dogs Eat Grass: Debunked

why do dogs eat grassHave you noticed your dog eating grass? You may be amused or alarmed. Eating grass, after all, seems like strange behavior for a canine. However, it’s not uncommon for dogs to eat grass either slowly, frantically and/or to throw it up afterwards. So you may wonder, why do dogs eat grass? The most commonly held belief why dogs eat grass seems to be to make themselves vomit. Now really, why would they do that? While no one knows for sure why dogs eat grass, let’s take a closer look into the possible reasons why dogs eat grass and debunk the most likely myth.

Why do dogs eat grass: the most likely myth

It is a commonly held belief that dogs eat grass to induce vomiting because they’re sick or their stomach is upset. Sometimes dogs will eat grass, vomit and then eat more grass. Or worse--eat their vomit! It just doesn’t really make sense that they would partake in this behavior due to an upset stomach.

The theory is that dogs will instinctively eat grass to make themselves vomit to rid themselves of a stomach bug or relieve an upset stomach. It’s assumed that grass tickles the throat and stomach lining which induces vomiting.

First of all, a dog does not need to eat grass in order to vomit. A dog’s body (just like humans) will naturally vomit when infected with a stomach bug or virus. Secondly, only about 1 in 4 dogs vomit after eating grass. If dogs ate grass to induce vomiting, you would think that grass will always make a dog vomit.

Since grass is non-toxic to dogs, it’s more likely that vomiting is due to eating grass too fast, which could occur from eating anything too fast, and not from the grass itself.

More likely reasons your dog is eating grass

While there are no proven facts as to why dogs eat grass (or why dogs sometimes vomit after eating grass), there are more than likely reasons why.

To improve digestion and relieve gastrointestinal issues

Dogs with an upset stomach may eat grass as an instinctual attempt to mitigate it. An interesting theory is that grass may aid in removing parasites from a dog’s intestines.

Also, a lack of fiber or digestive enzymes could potentially lead to a dog eating grass to improve poor digestion. You may want to try including probiotics and digestive enzymes in your dog’s diet to ensure good dog gut bacteria and help improve their digestion.

Tastes good

Many humans enjoy a salad...so why not dogs, too? Dogs eat pretty much anything (they are scavengers, after all) and do not discriminate eating when something tastes good.

Nutritional deficiencies

Why eat anything at all? To get the necessary nutrients necessary for survival. Grass contains important nutrients, digestive enzymes, fiber, minerals and vitamins. So dogs might eat grass if their diet is deficient in any of these areas.


You may notice your dog eating grass more often if they are not getting much attention from you in a day or if they are left alone outside for long periods of time. Sometimes a dog will nibble on some blades during an obviously boring moment in time. Dogs partake in all sorts of undesirable behaviors when bored or under-stimulated. More than likely, boredom is the reason your dog is eating grass.

Should I be worried about my dog eating grass?

The short answer is no. Grass is safe and non-toxic to dogs. However, you’ll want to make sure the grass your dog is eating has not been fertilized or sprayed with pesticides. These chemicals are extremely toxic to dogs and will remain in their system even if they throw the grass up.

Certain plants, weeds, trees and shrubs could also be dangerous for dogs so be aware of your dog eating grass and don’t allow them to eat harmful plants.

If your dog is constantly vomiting after eating grass and the frequency is high (multiple times a week), you’ll want to make sure you limit your dog eating grass. Frequent vomiting can damage your dog’s throat, esophagus, stomach and teeth. Also, if your dog is eating grass in conjunction with other symptoms such as diarrhea, weight loss and excessive vomiting, be sure to consult your vet.

How to deter your dog from eating grass

  • You can buy them their own little patch of grass (available at most pet stores) so that you know they are eating non-toxic grass.
  • Avoid certain problem areas where you know they are prone to eating grass. You can do this by blocking off patches in your backyard, watching them when they go outside, and going around certain spots on your walks.
  • You may want to switch up their diet if you suspect a nutritional deficiency.dog eating grass Make sure you know how to choose good dog food and to account for all the necessary nutrients in a homemade diet. You may also want to include supplements to make up for what their food doesn’t provide and to boost their health and wellness. Giving your dog vegetables such as spinach or broccoli could provide them with more fiber and may deter them from eating grass, as well.
  • The best thing you can do to deter your dog from eating grass is to get boredom off the table and keep them entertained with new toys, long walks and play time. Increased daily exercise for your dog will more than likely stop them from eating grass. Try throwing a frisbee, playing fetch, or dive into dog agility and training. Just throwing them a new bone or toy now and again will surely help.

While why do dogs eat grass remains an unresolved question, it seems the best thing to do to make your dog stop is to provide more stimulation, as boredom seems to be the most likely cause for the behavior. Next to that, by ensuring their nutrition and health are in check, you can rest assured that your dog eating grass is not a problem.  


Disclaimer: These statements have not been evaluated by the U.S. Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. Information contained or made available through the ColoradoDog website is not intended to constitute or substitute for legal advice or veterinary advice.

Leave a comment

Please note, comments must be approved before they are published