Why do cats eat grass? Is it safe?
Cats can’t digest grass well, but many nibble it anyway — probably an instinct that helped wild cats bring up fur, feathers and bones. Occasional grass eating is normal. Frequent eating followed by vomiting, or chewing houseplants, needs attention.
Why cats eat grass
- Instinct. Wild cats nibble grass after eating prey, which may help them vomit up indigestible fur, feathers and bones.
- Hairballs. Grass may help bring hairballs up or move them along — although a 2021 study found long-haired cats didn’t eat more grass than short-haired ones.
- Fiber. Grass that isn’t vomited passes through and may help mildly constipated cats.
- Parasites. In wild animals, plant fiber appears to help push out intestinal worms — possibly why the habit has stuck around.
- They like it. Some cats simply enjoy the taste and texture.
Is it safe?
Small amounts of untreated grass are generally fine. The real dangers are:
- Toxic plants. A cat used to chewing greens may move on to houseplants. Lilies are deadly to cats — even pollen or vase water can cause kidney failure. Dieffenbachia, philodendron, pothos and others cause problems too.
- Lawn chemicals such as pesticides and fertilizers.
- Too much grass, which can cause repeated vomiting or, rarely, a blockage.
- Parasite eggs in soil if your cat digs down to the roots.
When to see the vet
If your cat eats grass often and then vomits, or seems desperate for it, it can point to a gastrointestinal problem such as inflammatory bowel disease or parasites. Eating litter, fabric or plastic (pica) is also worth a check-up.
Should I grow cat grass?
It isn’t a medical necessity, but it’s a safe outlet for the urge to chew, especially for indoor cats. Look for oat, wheat or barley grass kits.
- Keep the soil damp but not soaked, and replace the pot if it gets moldy.
- Put it somewhere your cat can reach and move houseplants out of reach.
- Offer it as a treat-sized nibble — treats of any kind should stay under about 10% of your cat’s calories.
Frequently asked questions
Why does my cat eat grass and then throw up?
Grass irritates the stomach and cats can’t digest it, so vomiting is common. If it happens often, talk to your vet.
Is cat grass the same as catnip?
No. Cat grass is usually young oat, wheat or barley grass to chew. Catnip is a herb in the mint family that affects behaviour.
Do indoor cats need grass?
Not for nutrition if they eat a complete diet, but many enjoy it and it can keep them away from houseplants.
Sources
This article is general information, not veterinary advice. Every pet is different — for questions about your own pet’s health, talk to your veterinarian.
