How to Stop Your Dog from Chewing and Swallowing Grass

Why Do Dogs Eat Grass?

Dogs eat grass for a variety of reasons, but not typically because they’re lacking nutrients. While some believe grass provides fiber or helps induce vomiting, research shows these theories are weak. In fact, dogs often eat grass without vomiting, and studies found they eat more grass when on a standard diet than a supplemented one—suggesting it’s not about nutrition.

The most likely explanation is that dogs eat grass to purge their digestive systems. Like wild wolves and other animals, dogs may swallow grass whole to dislodge intestinal parasites or remove indigestible material. This behavior is inherited from their ancestors and is a natural instinct.

Is Grass Eating a Sign of Illness?

While occasional grass eating is normal, constant or obsessive grass consumption may be a red flag. If your dog vomits after eating grass every week, it could indicate gastric upset, food sensitivities, or underlying health issues like parasites or inflammatory bowel disease.

One study found that only 22% of dogs vomited after eating grass, suggesting vomiting isn’t the main goal. However, if your dog eats grass daily and shows signs of illness—such as greasy, yellow stools or weight loss—schedule a vet visit. A vet can check for parasites, food allergies, or digestive disorders.

When Grass Eating Becomes a Problem

If your dog is constantly eating grass and you’re concerned, consider environmental and dietary factors. First, ensure your lawn isn’t treated with fertilizers, herbicides, or pesticides—these chemicals can make your dog sick if ingested.

Also, monitor your dog’s diet. If your dog eats grass frequently, try switching to a high-fiber food or adding lightly steamed vegetables like carrots, kale, or zucchini. Some dogs stop eating grass when their diet improves, especially if they were lacking roughage.

What You Shouldn’t Do

Avoid using bitter sprays or pepper on grass or feces to deter grass eating. These methods often fail because dogs swallow food quickly, and the taste doesn’t register. Some dogs may also have adverse reactions to these substances.

Similarly, don’t assume grass eating is a sign of boredom. Dogs often eat grass during stimulating walks, so it’s not a behavior linked to inactivity.

When to See a Veterinarian

Take your dog to the vet if grass eating is sudden, obsessive, or paired with vomiting, diarrhea, or weight loss. These symptoms could point to a gastrointestinal issue, food sensitivity, or parasite infestation.

A vet can perform tests to rule out conditions like inflammatory bowel disease, allergies, or nutritional deficits. Early diagnosis helps prevent complications and ensures your dog stays healthy.