Generally cats and dogs eating a bit of grass can be seen as pretty normal behaviour and it shouldn’t be a cause for concern. There are a few possible reasons why cats might eat grass. Grass can have laxative effects and can induce vomiting so cats may be trying to purge themselves of something they have eaten. Or they may be trying to gain additional nutrients.
A close up of a black and white domestic cat eating grass
It’s no secret that cat cats spend a lot of their time grooming their coat to keep it in top condition. All this grooming may lead to excessive hair being swallowed which can block up the cat’s digestive tract and make them a bit constipated. It is thought that by eating grass the cat is instinctively self medicating their digestive issues in an attempt to get things moving through their system.
To Make Themselves Sick
Some cats will hunt and scavenge for food as well as the food they are given. When a cat eats prey they have killed it is highly likely that they will ingest things like hair, feathers or bones which they cannot digest. It is possible that these cats would then eat grass which they also cannot digest in an attempt to purge their stomach of other indigestible matter.
Grass contains folic acid which is an important vitamin for the production of haemoglobin. Perhaps cats instinctively know that grass is beneficial to their health and therefore choose to consume it.