Why does my dog eat grass?

Nutrient deficiency. Sometimes, eating grass is a form of pica, or ingesting strange items, which can be caused by a diet deficiency. Many deficiencies are rooted in missing vitamins, minerals, or nutrients. Your dog’s daily food intake may be lacking in one of these areas.

Instinct. Domesticated dogs have different lifestyles than those of wild canines — their digestive systems, nutritional needs, and cravings have evolved. Canines in the wild obtained their primary source of nutrients from eating an entire animal, especially if that animal’s diet consisted of plants. Domesticated dogs, on the other hand, are omnivores and genetically want to eat grass to get those extra nutrients they’re lacking without hunting wild game.

Taste. Dogs might simply enjoy the taste and texture of grass, especially when new grass is growing during spring or if it’s wet after a fresh rain.

Boredom or anxiety. Although most dogs enjoy being outside, some get bored and need something to do to pass the time — like munching on some grass. Anxious dogs also eat grass as a comfort mechanism, similar to people who chew their fingernails.

Upset stomach. Many dog owners think their pup is eating grass because they have an upset stomach and they’re trying to make themselves throw up. It’s tough to know whether a dog is eating grass to throw up, or if they’re already throwing up and think the grass will help settle their stomachs. A self-reported study showed only 22% of dogs actually vomited from eating grass and 9% showed signs of feeling sick prior to eating grass — so it’s actually not likely that your pup is eating grass because they’re sick.

Regardless of why your dog is eating grass, it’s not the best for them to regularly snack on. While the grass itself isn’t usually harmful, it could be sprayed with herbicides and pesticides that are toxic to dogs. Your dog could also ingest intestinal parasites, such as hookworms or roundworms, that are found in the grass from other animals’ fecal residue.

👉 Here’s a list of pet-friendly pesticides to protect your pet while getting rid of pesky bugs.

Dogs that eat a large amount of grass, especially small breed dogs, are also at risk of intestinal blockages and constipation. Large clumps of grass can bind together in the intestines, making it more difficult to pass.

If your grass-grazing dog shows other symptoms of stomach discomfort — such as vomiting, diarrhea, weight loss, decrease in appetite, blood in stool, lethargy — or if they’re eating grass more frequently than normal, they may have a more serious issue such as inflammatory bowel disease, gastric reflux, or pancreatitis. If you notice these or any other signs of illness, it’s best to have your dog seen by your vet as soon as possible to rule out any possible underlying causes.

If your dog eats grass periodically, there probably isn’t too much of a concern. That being said, you should have them regularly checked for parasites just to be sure they aren’t picking anything up from the grass.

Make sure to stop your dog from eating any grass that’s been recently treated with herbicides or pesticides since these can be extremely toxic to dogs. As long as your dog isn’t getting parasites or consuming toxic chemicals, they’re probably fine to eat grass every once in a while.

It may be a good idea to bring this behavior up with your vet during your dog’s next appointment, though, just to be sure your vet doesn’t have any concerns.

How to prevent it

Dogs that work for treats may be trained to stop the grass eating in exchange for something tastier. Any time your dog goes to nibble grass on a walk or during a potty break, redirect them to walk in another direction or offer a verbal cue and give them a treat when they listen. The same idea can work even if your pup isn’t interested in treats. Some dogs are more driven by affection. Instead of giving a treat as a reward when they listen, simply give them pets and praise.

If your pup is determined to graze, you could try putting a basket muzzle on them while they’re outside in the yard — especially when you can’t keep your eye on them at all times.

It’s common for dogs who eat grass to lack fiber in their diet. Carrots, green beans, broccoli, and pumpkin are healthy choices that can be added to their meals to up their fiber intakes. Your veterinarian might also prescribe over-the-counter fiber supplements or a specialty, high-fiber kibble depending on your pet’s specific needs.

You can also try adding a probiotic to your dog’s food to help with their overall GI health, which could possibly deter grass-eating if it’s caused by an upset stomach.

Avoid toxic pesticides — Use pet-safe pesticides or herbicides on your lawn or designate a lawn space as the “dog-safe area” that is left untreated.

Clean up poop — Pick up and dispose of dog poop regularly, especially if you have other dogs come over frequently. This will help eliminate the chance for your dog to ingest parasites from other dogs’ leftover poop residue.

Keep an eye out for toxic plants — Keep an eye on your yard for any unwanted weeds and pull them when necessary. Some weeds that grow throughout the year can pose a threat to your dog if ingested. For example, foxtail seeds can cause major GI issues and poisonous mushrooms can cause severe allergic reactions.