Seeing your dog eating grass for the first time brings up a lot of questions in a concerned owner. Is she hungry? Bored? Sick? Weird? Is she going to get sick by eating grass? Well, rest assured – dogs eating grass is actually quite common and doesn't usually cause problems. In fact, most veterinarians consider it a normal dog behavior. Dogs may eat grass for a variety of reasons. But understanding why your dog does can help you curb her behavior.Upset Stomach Dogs do not have the means to digest grass, as they lack the enzymes needed to break down the fibers. Thus, there is little nutritional value in it for them. One reason for eating grass may be due to a feeling of nausea, particularly if your dog is eating the grass and then throwing it up. It is possible that dogs learn this is a temporary solution for stomach irritation. Simple Evolution For those with a scientific bent, an additional theory related to the grass-eating has to do with their evolutionary past. For ancestral dogs to have survived successfully, they would have needed good hunting abilities in order to feed and nourish their young and survive as a pack. Grass eating may have evolved to help conceal their scent from their prey in the same way that rolling in foul offal is sometimes thought to. Boredom Are you providing regular exercise and mental challenges for your pup? Do you notice your dog eating more grass during times when you aren’t walking or playing with them as often? With some dogs, eating grass is just something to do to pass the time. She may be alone with the whole backyard at her disposal but find there's not much to do. Hunger Another common theory is that dogs will eat indigestible matter if they are excessively hungry or if their nutrition is poor, so this must always be a consideration. If you are preparing homemade food, be sure to consult a professional to make sure the nutritional balance is correct.