​It’s not at all uncommon to see your dog munching on grass in the backyard.

But is this something that should worry you? Many pet owners wonder, “Why do dogs eat grass?” Is it something to worry about? Is it a sign of illness, or some other kind of problem?

Let’s take a look at why your pooch might be doing this, and as always, if you’re concerned talk to your vet.

Potential Reasons Why Dogs Eat Grass

Dogs are notorious for eating things other than food. They’ve done this for thousands of years. Dogs who crave non-food items, and regularly eat them, have a condition known as “pica.” Your pup’s ancestors were scavengers. They ate whatever they could in order to survive. And while these days, domesticated dogs enjoy regular bowls of kibble, they still have that scavenging instinct. And in many cases, they’ll eat whatever they can get a hold of. That may include grass, but it could also include dirt, rocks, soap, and other things.1

Sometimes, a case of a dog eating grass is nothing more than the result of boredom.

In some cases, the answer to the question of, “Why do dogs eat grass?” is that they have some sort of nutritional deficiency. However, the evidence to support this theory is lacking.2

Dogs Eat Grass | Ultimate Pet NutritionWhen a dog eating grass leads to throwing up, that will make things even more concerning for a pet owner. There are conflicting theories as to why this happens. Some think that a dog will do this if they’re not feeling well, in hopes that eating grass will lead to vomiting. Others believe that dogs don’t have the mental capacity to actually treat their upset stomach by ingesting grass.3

The evidence tends to lean toward the latter theory. Research shows that less than 10 percent of dogs show signs of being sick before they eat grass. And evidence also shows that this behavior isn’t even that effective when it comes to inducing vomiting. A dog will throw up less than 25 percent of the time after consuming grass.4

There are some other possible reasons why dogs eat grass. It could be a sign that your dog has intestinal worms, is having digestive problems, or needs more fiber. Some vets believe that adding fiber to a dog’s diet could stop this behavior.5

Then there’s the possibility that dogs simply like the way grass tastes! But…

Should I Let My Dog Eat Grass?

Next to the question of, “Why do dogs eat grass?” the thing owners want to know the most may be, “Should I let my dog eat grass?” Most experts believe that dogs eating grass is a harmless behavior.6

Dogs Eat Grass | Ultimate Pet NutritionHowever, it could be a big problem if your lawn has recently been treated with an herbicide or pesticide. And, if your dog likes to munch on plants in addition to grass, there are dangers. Several common plants are toxic to dogs. If you’re unsure whether a certain plant is toxic, the American Society for the Prevention of Cruelty to Animals (ASPCA) has a website that lists poisonous and non-poisonous plants.7

Generally, however, eating grass isn’t dangerous for your dog. Grass may even contain nutrients that could be beneficial for your dog – especially if they’re on a commercial diet. If this habit has you concerned, talk to your vet to see if there is some sort of health issue. Your vet may recommend that you add vegetables and fruits to your dog’s diet.8

When To Be Concerned

Even though some of the reasons behind why dogs eat grass seem harmless, there are others that could mean your dog is dealing with some sort of problem. Watch your pet closely when they are outdoors. If your dog starts to suddenly increase their intake of grass, that could mean there’s an issue. You also have to be careful if you have a puppy who likes to graze. Puppies have a tendency to not only ingest grass, but also leaves, and even sticks. This could lead to a potentially dangerous intestinal obstruction.9

The Bottom Line

So, why do dogs eat grass? There are a lot of possible reasons. Most of the time this is harmless behavior, but it also bears watching. If your pet seems to be eating grass more than usual, take them to the vet to get checked out.

Learn More:
Best Family Dogs for Kids: 8 Breeds You Don’t Want to Miss
Finding Mucus in Dog Poop – Should You Be Concerned?


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About the author

Dr. Gary Richter, MS, DVM loves animals, and is passionate about keeping them healthy and happy as long as possible. He has received more than 30 awards due to his expertise in the field, and The American Veterinary Medical Foundation recently named Dr. Richter “America’s Favorite Veterinarian.” Dr. Richter has been at the forefront of pet nutrition for two decades, and he is also the author of the bestselling “The Ultimate Pet Health Guide.”