Grass eating occurs frequently among dogs and cats and it is thought to be normal behaviour. Feral cats, (i.e. cats that roam free in the wild), eat grass almost daily and most domesticated cats, if given the opportunity, will eat grass and certain plants.
The reason for this activity is unknown, although some theories exist. Some experts feel that cats eat grass for nutritional reasons, such as adding fibre or bulk to the diet. Others feel that cats eat grass as a form of self-medication, called zoocognopharmacy. They theorize that cats eat broad-leafed grasses to take advantage of their laxative effects while narrow or sharp-leaved grasses or plants are ingested to act as emetics to make themselves vomit. Still others feel that cats eat grass as a tonic to settle their stomachs.
Whatever the reason, dogs and cats seem to enjoy this activity and owners can safely encourage this habit by providing sources of green vegetation.
Cat owners can consider growing a small plot of lawn grass or wild oats that their cat can access or, if this is not possible, they can provide an occasional side dish of green vegetables like string beans. Dogs can also be provided with various green vegetables.
Ask your veterinarian which vegetables and plants are safe to feed your pets and which are potentially harmful.