Why does my cat eat grass?

What it often means

• Taste and texture: many cats simply like chewing tender blades of grass, with nothing wrong behind it.
• Swallowed hair: grass may help hair swallowed during grooming pass through or come back up. It is often said, but not proven.
• An old inheritance: one hypothesis holds that eating plants helped his wild ancestors purge intestinal parasites. Plausible, not proven.
• Sometimes nausea: he eats fast, eats a lot, then vomits. But many cats graze without any sign of feeling sick.
• Boredom in indoor cats: with no grass around, he chews houseplants and bouquets, and that is where the risk begins.

Signals to read at the same time

• The manner: a few blades chewed calmly, or large amounts gulped down at once, with swallowing and lip licking.
• What follows: nothing, a single vomit of grass and hair, or repeated vomiting, drooling, a lethargic cat.
• The plant: yard grass or cat grass, or a houseplant, a bouquet, leaves fallen from a vase. Always check which one.
• The hairballs: one now and then is common; regular vomiting, even of hair only, is not normal: it can come from a digestive problem, or from a cat who is overgrooming.
• What else he chews: plastic, fabric, cardboard he swallows. If the list grows, it is no longer just about grass: read why cats chew plastic.

What you can do

• Grow a pot of cat grass, sprouted oats, wheat or barley, and replace it when it turns yellow: he gets something safe to chew.
• No lilies in a home with a cat, not even in a bouquet: every part of the plant is toxic to him, including the pollen and the water in the vase.
• Before you buy a plant or accept a bouquet, look it up in a reference database such as the ASPCA’s, or ask your vet: other houseplants and cut flowers are toxic too.
• Outside, use no weed killer, fertilizer or slug bait where he grazes: he swallows them with the grass or when he licks his paws.
• Note each vomiting episode: date, time, what he ate before. If it keeps happening, those notes will help your vet.

When to see a vet

Go to the vet right away if he chewed or licked any part of a lily, even a little pollen on his fur or water from the vase, without waiting for symptoms: kidney damage responds best when treatment starts early. Also see a vet if he vomits regularly, even just grass or hair, drools, stops eating, loses weight or seems to have belly pain: digestive disorders, parasites or a foreign body can be behind it.