There Might Be A Simple Explanation For Why Dogs Eat Grass


Jack Dunhill

Social Media Coordinator and Staff Writer

clockApr 22 2021, 12:25 UTC
dog grass snack

The park is a perfect place for a green buffet. Image Credit: Radharani/

There really is nothing like taking your dog to a beautiful beach, mountain, or lake, ready for whatever adventures the day holds, and they take the immediate decision to run to the first patch of grass and start stuffing their face. From the offset, the behavior makes no sense – dogs don’t generally spend their days eating their leafy greens and shouldn’t particularly enjoy the taste, and the heavy cellulose content makes it nigh impossible for a dog to fully digest. 

So, why do dogs eat grass?  


Do Dogs Eat Grass To Be Sick? 

If you’ve ever asked this question, you will have almost certainly been greeted with the immortal line "dogs eat grass when they have an upset stomach so they can be sick". This stems from pet owners often noting their dogs throw up after a grassy snack, although it has never been clear whether the grass-eating results from illness, or whether it causes the ensuing vomiting. However, science says that the answer may be neither. 

In a self-reported study looking into dogs’ vegetation eating habits, researchers discovered that a huge 79 percent of dogs had chowed down on grass at some point in the past. Despite this high number, just 9 percent of these dogs appeared ill beforehand, and only 22 percent of them vomited after eating the grass. That leaves the majority of dogs appearing healthy, eating a bunch of grass, and then going about their day happy and illness-free. 

While there hasn't been too much further research into the subject, the large sample size certainly suggests that a human’s best friend is doing this odd habit for another reason.  

Do Dogs Enjoy Grass? 

Sometimes, the simplest answer is the best. While we may never fully understand this behavior, the current leading explanation is that they may actually just enjoy the fresh flavor of grass. Owners often note an uptick in grass-eating as spring comes around, so maybe the newly-grown grass is just a nice treat.  


Many people think dogs – like cats – are obligate carnivores, meaning they should fully derive their diet from meat. However, research has shown that dogs and wolves are actually (almost) omnivores, and grab a healthy portion of their daily nutrients from vegetation. 

Multiple studies have found evidence of greenery and berries in the diets of wild wolves, suggesting it makes up a small but significant part of their intake. Alongside this, grass is a fantastic source of fiber, something that can easily go lacking in the average dogs’ diet. Snacking on the tough roughage may help the dogs move things along, as well as substituting for an integral part of a healthy diet. 

They may look like they only eat meat, but wolves are partial to some greenery every now and then. Image Credit: Ramon Carretero/

 So there you have it – grass is almost definitely not a recipe for vomiting, but instead something dogs do intentionally for either enjoyment or nutrition. It is not necessarily a bad thing, though ensure the vegetation is free from harmful pesticides and herbicides before your pooch stuffs themselves full. 


 This Week in IFLScience

Receive our biggest science stories to your inbox weekly!