Why Do Dogs Eat Grass?
Surely, on your daily walks with your dog, you will have noticed that, on occasions, it eats grass. About 8 out of 10 dogs eat grass and green shoots from time to time, but why do they do it? Should you let your dog eat grass or stop it?
Let's start by talking about some of the most common answers to “why do dogs eat grass?”.
Dogs Eat Grass to Purge
The usual answer to this question is usually "to purge". They use the grass as a natural solution to vomit and thus eliminate an upset stomach. However, it does not mean that eating grass is associated with any disease or stomach problems. Many healthy dogs eat it without any previous digestive problems, and do not vomit afterwards. So why do they do it?
Dogs Eat Grass to Add Nutrients and Minerals to Their Diet
Grass, in addition to being rich in fiber, provides an extra supply of vitamins and minerals. However, some research shows that dogs have the same motivation to eat it even with a complete diet rich in fruits and vegetables. Maybe for dogs that always eat the same thing, especially dry food, it is a way to break the monotony and add a small fresh bite to their diet?
Dogs Eat Grass Because of an Inherited Behavior
Eating grass is a natural behavior in many dogs, which seems to have been inherited from wolves. In wolves it seems to be a purging method to remove worms and intestinal parasites as the fiber in the grass increases intestinal contractions and helps drag parasites through the intestinal tract. Unlike wolves, dogs are usually dewormed and, in general, it does not imply the presence of intestinal problems or diseases, it is an instinctive behavior.
It could also be an instinctive hunting behavior to eliminate the scent near possible prey, as they do when rolling on the ground, rolling on grass, dead animals, etc.
Dogs eat grass because they are hungry and they like it
The answer may be simpler than you think, and that is simply that they may like grass. As they like to eat fruit and vegetables, they may also like the taste of grass, sniff and nibble on the juiciest shoots. Also, there are studies that show that dogs tend to eat grass when they are hungry. Puppies, more active and curious, tend to eat more grass than adult dogs.
UC Davis research
The University of California, Davis, conducted a research about this dog behavior in 2008. The initial study was a survey of 25 veterinary students who had pet dogs. All of the students reported that their dogs ate grass. None reported seeing any signs of illness before their dogs ate the grass and only 8% said that their dogs regularly vomited after eating it.
With these results in view, the researchers decided to go ahead with the study and chose a sample of 47 dog owners. Of these, 79% said that they had observed their dog eating plants (mostly grass). Only 4 of the surveyed admitted to having observed signs of discomfort in their dog before it ate the grass and only 6 stated that their dogs had vomited after ingesting it.
After these two preliminary studies, the researchers decided to go ahead and expanded the sample to 1,571 dog owners. Again, 68% said their dog ate grass frequently. Only 8% said they had observed signs of discomfort before eating the grass and only 22% indicated that their dog vomited after eating it.
The study concluded that most dogs eat grass and that this is a natural behavior. Also that, generally, this behavior is not associated with any disease or upset stomach. That is to say that they do not do it to purge themselves because they feel bad or they want to expel something that bothers them inside their stomach. Although it seems that, in those dogs that show symptoms of illness before eating grass, the vomiting reaction is more frequent.
The study also found no evidence that dogs eat grass to fill a nutritional deficiency because those dogs that had plant supplements added to the diet (vegetables or fruit) showed no more motivation to eat grass than those that received a diet without supplement.
Should we let our dog eat grass?
In a healthy dog, eating grass does not have to mean any problem and therefore there is no reason to prevent it. However, the danger that we need to be especially careful is if the grass is contaminated with insecticides or toxic fertilizers since it could be poisoned, or watch that it does not ingest any toxic plant. I can also provoke gastritis.
In any case, you should contact a pet expert in case it becomes an excessive or compulsive habit.