Why Do Cats Eat Grass? Instinct, Digestion and Safe Cat Grass
If you have ever watched your cat nibble on a lawn, you may wonder whether it is sick, hungry or just being quirky. Grass eating is common in cats, including strict carnivores that get all nutrition from meat. The reason remains one of cat behavior's small mysteries.
Theories
Fiber and digestion. Grass provides fiber that may help move food through the gut.
Hairball control. Some people believe grass helps cats bring up hairballs or pass them. Evidence is limited, and many cats do not vomit after eating grass.
Folate and nutrients. Grass contains folate, a vitamin that some think cats may crave, though cats on balanced diets do not need extra.
Natural instinct. Wild cats and their relatives eat plants, which may help clear intestinal parasites.
Taste and texture. Some cats just like it.
Boredom or stress. Indoor cats may chew plants for entertainment.
Nausea. Some cats eat grass to settle an upset stomach, though vomiting is not required.
Researchers have found that many cats eat grass, most seem healthy and only a minority vomit afterward.
Is it normal?
Yes. Occasional grass nibbling is not a cause for concern if the cat is healthy, eats regularly and has normal stools. See cat vomiting causes for when vomiting needs attention.
When to worry
Contact your vet if your cat:
- Eats grass compulsively or constantly
- Vomits repeatedly, or has blood in vomit
- Has diarrhea, weight loss or lethargy. See diarrhea in cats.
- Eats non-food items, such as fabric or plastic. This may be pica.
- Eats toxic plants
- Shows changes in appetite or behavior
See the emergency warning signs guide. Use the US vet directory to find a clinic.
Grass dangers
- Pesticides and fertilizers. Lawn chemicals can poison cats. Keep cats away from treated lawns, and use pet-safe products.
- Parasites. Outdoor grass can carry parasites or feces. See worms in cats.
- Toxic plants. Cats may chew lilies and other poisonous plants. See toxic houseplants for cats and lilies and cats.
- Grass seeds, which can lodge in ears, nose and throat.
Safe cat grass
Cat grass is typically wheat, oat, barley or rye grass grown for pets. It is safe, inexpensive and easy to grow indoors.
- Buy organic seeds or a kit.
- Soak seeds overnight.
- Plant in a shallow container with potting soil.
- Keep moist and in a bright spot.
- Grass is ready in about a week to ten days.
- Trim and replace when it yellows.
Place pots away from toxic plants. Rotate pots so there is always fresh grass. See cat-safe houseplants for other safe greenery.
Protecting your plants
If your cat chews houseplants, give it its own pot of grass. Move toxic plants out of reach. Use deterrents such as citrus peels sparingly, since some oils are harmful. See cat-proofing your home.
Indoor cats and boredom
Cats that chew plants may need more stimulation. See indoor cat enrichment ideas. Offer puzzle feeders, safe chew toys and play.
Catnip and other herbs
Catnip and silvervine are safe for most cats and provide fun. See is catnip safe for cats.
Grass eating and parasites
One idea is that grass eating is an ancient way of clearing intestinal worms, since the rough blades may help move parasites through the gut. Studies of wild primates and of dogs have raised this idea, but it is unproven in cats. Whatever the reason, regular deworming and a vet-approved parasite plan matter for every cat, especially those that hunt or go outdoors.
How much grass is too much
Nibbling a few blades now and then is normal. If your cat eats large amounts every day, vomits each time, or seems driven to chew grass and other plants, discuss it with your vet. Possible causes include nausea from digestive disease, a diet lacking enough fiber, intestinal parasites or, rarely, behavioral pica.
Fiber in the diet
Some vets suggest a higher-fiber diet or a small amount of plain cooked pumpkin for cats that eat grass often. Do not change your cat's diet without advice, and introduce any new food gradually. See how to switch cat foods and can cats eat pumpkin.
Outdoor cats
Cats that roam are more likely to meet treated lawns and toxic plants. A secure garden or a catio makes grass time safer. See how to build a catio.
Kittens
Kittens explore with their mouths, and may nibble plants. Provide safe options, and keep hazards away. See kitten-proofing your home.
Frequently asked questions
Is it normal for cats to eat grass?
Yes, it is common and usually harmless.
Does grass help hairballs?
Possibly, but there is no firm proof.
Why does my cat throw up after eating grass?
Grass can irritate the stomach, and some cats vomit afterward.
What is cat grass?
Usually wheat, oat, barley or rye grass grown for pets.
Sources and further reading
Behavior problems often have medical or emotional roots. These specialist bodies explain how professionals assess them.
- American College of Veterinary BehavioristsFind board-certified veterinary behavior specialists.
- ASPCA Animal Poison Control CenterToxic plants and foods lists, plus a 24-hour helpline.
- Pet Poison Helpline24-hour poison advice staffed by veterinary toxicologists.
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