Why Do Dogs Eat Grass?

It may seem that your dog has decided to become a cow, so let’s review the myths behind the question of why dogs eat grass.

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Dr. Jerry Murray

Dogs often do things that don’t make sense to us humans. One of those things is eating grass. Eating grass is a common issue with dogs of all sizes and breeds. There are a lot of guesses as to why dogs eat grass, but we really do not know the exact reason for this. I will cover some of the various theories about why dogs may eat grass and the treatment options to help stop this behavior.

Do Dogs Eat Grass To Cause Vomiting?

One of the common myths is that dogs eat grass to vomit. I thought this was the case, too; however, a research article disproved this theory. Most dogs who eat grass simply do not vomit afterward. I know some dogs, including my own dog, who will vomit if they eat a large amount of grass quickly, but the majority of the time, dogs do not vomit after ingesting grass. The research also showed that most dogs who eat grass show no signs of being sick or having an upset stomach before or after eating grass.

Do Dogs Eat Grass Due To A Nutritional Problem?

Another common belief is that dogs eat grass because they have some kind of a nutritional deficiency. Thus, they are trying to get some needed nutrient from the grass. I know this sounds logical, but it is not likely to be the reason why your dog is eating grass. Just about all commercial dry and canned dog food is nutritionally balanced, so your dog should not have a deficiency of any of the required nutrients. In addition, your dog will not be able to digest the grass, so it is basically just extra fiber that your dog will defecate out. If your dog is on a low-quality food or a low-fiber diet, then it is possible your dog is eating grass for the extra fiber.

Do Dogs Eat Grass Because Of A Behavioral Problem?

It has been suggested that dogs kept outside in a plain environment are more likely to eat grass. This would imply that the dog is bored or anxious, so the dog starts eating grass to try to solve this problem. This is not the case for most dogs. Now, if your dog is anxious before he starts to eat grass, then this may be a viable reason. For a very few dogs, eating grass may a part of an obsessive-compulsive disorder (OCD). If your dog shows signs of being obsessed with eating grass then it is possibly an OCD-related problem.

Do Dogs Eat Grass Because Of The Taste?

Another possible reason why your dog may eat grass is just because he likes the taste of it. This would be similar to people who actually like to eat salad. Thus, your dog may simply enjoy eating grass, despite the lack of any nutritional benefit (unlike salad for people, which usually is nutritious).

Is It Dangerous For Dogs To Eat Grass?

Some animal behaviorists consider eating grass to be a normal behavior for dogs. In general, a small amount of grass is safe for your dog to eat; however, you must be sure your pet avoids grass treated with any herbicides, pesticides or fertilizers. Obviously these items could be toxic and cause serious problems for your dog.

You have to be cautious if feces from another dog, cat or wildlife might also be ingested with the grass. The fecal matter could cause a bacterial infection or a parasitic infection for your dog.

Another concern is toxic lawn plants being ingested along with the grass. This could cause serious problems, especially with smaller dogs.

In addition, some grass contains sticker burrs. I had to help pull hundreds of little sticker burrs out of a dog’s tongue and mouth earlier this year. It was the worst case of sticker burrs I have ever seen. This was rather painful for the dog, so be very careful that your dog avoids eating sticker burrs along with grass.

How Do You Stop Dogs From Eating Grass?

This is the difficult part. Your veterinarian will try to determine what is causing your dog to eat grass, and then tailor the treatment based on the cause. In most cases, I recommend a good-quality, high-fiber diet. This eliminates any nutritional concerns and provides plenty of additional fiber.

If your dog is kept mostly outside and boredom may be part of the problem, then environmental enrichment is recommended. I suggest offering several chew toys like the indestructible Kong toys or Jolly Balls. Medium and large breeds may also enjoy playing with soccer balls, volleyballs or Frisbees. Medium and smaller breeds may enjoy playing with tennis balls. In addition to toys, your dog will benefit from more exercise and more social time with you and other people.

In those rare cases when anxiety or obsessive-compulsive behavior is involved, then a pheromone releasing collar or medications may help your dog.

Remember, occasionally eating a small amount of grass that does not have any herbicide, pesticide or fertilizer on it is not likely to harm your dog. On the other hand, a serious problem may be involved if your dog is vomiting frequently, having diarrhea and/or losing weight. In such cases, I would recommend taking your dog to your veterinarian for some bloodwork and possibly other diagnostic tests, such as radiographs and ultrasound, to determine what is actually causing your dog’s illness.

Article Categories:
Behavior and Training · Dogs