Some dogs love to eat grass. This habit usually has no bad side effects, except perhaps when he throws up the odd time. This does not affect the dog too much. He will just vomit and be on his way. It probably bothers you more than your dog. Why dogs eat grass is a complex problem which has a variety of conjectures.
Some believe that dogs eat grass in an attempt to add more nourishment to their food. So many dogs will eat other things besides meat-grass being one of them. They think dogs are trying to balance their diet of meat with some 'salad' on the side. If you are feeding your dog on high quality food with all the nutrients that he needs, he may not eat grass, but if he is only fed meat alone, this could influence him in his choice of food.
Feeding your dog canned food does not promote healthy teeth and bowels. For the most part, kibble should be the main part of a dog's diet. It keeps him regular and his teeth clean. For a little variety, he can be fed a few spoonfuls of canned meat.
Another theory is that dogs eat grass to ease their stomach discomfort when having a feeling of nausea. But dogs do not need to eat grass to vomit. It is true that sometimes they do throw up after eating grass, but this theory is merely speculation.
If your dog is a grass eater, make sure that the grass has not recently been treated with weed killer or pesticides. Except for that, you need not worry about it, because eating grass does not hurt your dog. Since there is no evidence that it is detrimental to your dog's health, you can be assured that eating grass is just something your dog likes to do. Even if he throws up once in a while, this habit will have no undesirable effects on him.
Supervising him on leashed walks will help alleviate the problem. You will be able to restrict his desire for grass if he starts to eat it, if you feel it necessary.
Truthfully though, there really is not a lot you can do about the grass-eating habit, since nobody really has an answer to why dogs eat grass. Experts seem to believe that it is just one of those things that some dogs enjoy. Preventing your dog from eating grass may deprive him of this pleasure.
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