Why Do Dogs Eat Grass?

Whenever I walk one of my dogs or let them outside to potty, I notice that they occasionally graze the grass. 

Tiny puppy laying in the grass

Most of the time, I do not think much of this behavior.  But, I do begin to grow concerned when I see my dog eating grass like he’s chowing down a bowl of his favorite food.

Does he not like his food?  Is he sick?  Will grass harm him?

If you have been pondering the same questions, do not worry.  There are answers

Dog owners should take a minute to understand why dogs eat grass and whether there is a time to worry or not.

Do all dogs eat grass?

Exceptions exist for all generalizations, but yes, it is normal behavior for dogs to graze on grass.

Dogs eat grass because of a mental behavior known medically as pica.  This is the term that refers to the constant consumption of materials with no nutritional value.

It is rare for humans to display signs of pica, but pica is more common in wild and domestic animals, like dogs.

Reasons dogs like eating grass

Determining why dogs like to eat grass is difficult since they can’t tell us right out.  Veterinary studies have put forth some suggestions, but nothing is conclusive yet.

Many people believe dogs will eat grass if they are feeling ill or if they have intestinal worms.  Some also believe this behavior is an attempt to improve digestion.

The belief that dogs eat grass if they are ill presumes that they do this to induce vomiting to purge whatever is ailing them.  However, animal experts do not find a correlation between dogs eating grass and vomiting.  Nor do results show a correlation between grass-eating and worms or indigestion.

Shih Tzu laying in the grassWhy do dogs eat grass?

Most of the time, dogs do not vomit after eating grass. If they do, it is not uncommon for them to go right back to it.  This is true for eating grass or any other activity.

Dogs do not vomit like humans do.

When we get nauseous, it usually a sign of illness, but dogs can vomit from something as simple as eating too fast or getting too excited after eating.

Recall your dog’s behavior before eating grass and pay attention afterward.  Was, or, is he displaying any signs of illness?

Signs of illness you need to look for in your dog do not include eating grass, but instead includes the following:

  • Frequent vomiting and nausea

  • Diarrhea

  • Coughing

  • Hair loss -- not the same as shedding, but is irregular hair loss from skin infections

  • Frequent scratching

  • Loss of appetite -- eating grass is the opposite of this!

  • Slothfulness

  • Irregular urination patterns -- urinating too much or too little can be symptoms of illness

  • Stiff joints and immobility

If your dog is eating grass, but not exhibiting any of the symptoms mentioned on this list, then he is probably feeling fine!

If your dog does show signs of anything on this list, then you should take him to the vet, regardless of whether or not he is eating grass.

If not because of illness, then why do dogs eat grass?

It is good news that eating grass is not a sign of sickness, or my dog must be very sick!  Since pica is not a sign of illness, let’s take a look at why veterinary experts think dogs eat grass:

dog laying down in the grass with his ball
  • Dogs may eat grass because they are bored.  Simple as that.  Your dog may be eating grass for the same reason that he chews a sock or gnaws on a bone.  This is especially true for puppies who are still exploring their surroundings and getting into everything

    Try giving your pet a chewing toy or bone.  Maybe he needs to play more!  Giving dogs some attention and excitement will help alleviate their boredom.
  • Your dog may be lacking something in his diet.  Your dog’s food may not be packed with all of the nutrients he needs.  Some owners find that switching to foods with higher amounts of fiber keeps dogs from wanting to eat grass or other objects.
  • Your dog simply likes it!  Just as humans enjoy certain foods for texture, it is possible that your dog likes grass for the same reason.

Are there harmful side-effects to eating grass?

Dogs are quite capable of digesting both plant and animal matter.  While dogs usually prefer eating meat or dog food, they sometimes enjoy plant foods as well.

In principle, eating grass is not harmful to your dog.  But, if your lawn is treated with fertilizers and chemicals, eating it can be harmful.

If you know your lawn is absent of these toxins, then your dog will be fine!

If your lawn is treated with chemicals, or if you are not sure, then you should keep your dog from eating grass.  The same goes for grass in unknown areas while walking your dog or traveling.

As mentioned before, you can discourage this behavior by playing with them more and giving them something else to chew on.  Your dog may even enjoy another similarly textured plant like celery!

Final thoughts on why dogs eat grass

Pretty dog in a field

Eating grass is a normal behavior for dogs.  This behavior is not shown to be a sign of illness, worms, indigestion, or whatever bad thought we can imagine.

You should not worry about your dog eating grass unless the grass is fertilized or chemically treated.

If fertilizer and toxic chemicals are not a problem, then let your dog be a dog and enjoy some harmless grazing!

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