Why do cats eat grass and how does it affect them?

30 March 2021

Cat eating grass? Learn the causes, effects and alternatives to this behavior and what to keep in mind when your cat is playing outside!

brown cat outdoors

When sharing your home with a cat you’ll inevitably discover the occasional odd behaviors they exhibit. Like for instance, why do cats eat grass? Some behaviors might be charming and entertain you, but it’s important to know if your cat eating grass is safe. Find out why it’s perfectly natural for cats to eat grass, and when you should be worried. Plus, discover some natural alternatives to grass to offer your kitty. While you’re here, find out if your cat suffers from a pollen allergy and what you can do about it.

So it’s official – cats eat grass. You’ve likely already observed this in your own kitty. In fact, researchers at the University of California, Davis, Veterinary School of Medicine conducted a survey among cat parents, in which they made the following findings:

  • 89% of cats ate grass six or more times throughout their lives.
  • 11% of cats were never observed eating grass.
  • 91% of the time, cats appears in good health before eating grass.
  • 27% cats vomit frequently after eating grass or other foliage1

This research shows that nearly all cats eat grass – and are typically in good health when doing so. A widely-believed but inaccurate explanation for this is that cats eat grass to induce vomiting after they have been sickened or poisoned – but that’s not always the case. The researchers found that, after eating grass, most cats do not always throw it up – or show any signs of illness1. Cats can be purrfectly healthy, and still eat grass. So that brings us to the question – why do cats eat grass anyway?

Why do cats eat grass?

In short, cats eat grass because its comes naturally to them and can support their health – in the same way, eating leafy greens helps humans to stay healthy. Here are 5 reasons why cats eat grass:

  1. Cats actually lack the stomach enzymes needed to break down and digest grass – and as a result, they sometimes regurgitate it. By vomiting out the grass, hairballs or inedible parts of prey, such as fur or bones, are expelled as well.
  2. The fiber found in grass supports digestion and can help relieve constipation.
  3. Anxious or stressed cats may find that chomping on the green plant helps to calm their nerves.
  4. Cats may eat grass as a source of vitamins and minerals, such as folic acid (B9), that they may not be getting elsewhere.
  5. Eating grass may help your kitty to expel internal parasites (or atleast, this may be a leftover instinct from your cat’s ancestors)2.

Plants like grass contain fiber and other nutrients which are important for good health.

When to be concerned about your cat eating grass

If your cat is eating grass every day or vomiting blood, there is definitely cause for concern.

⚠️ Warming: Munching on grass every day might indicate problems in your pet’s digestive system.

The more trouble they have digesting their food, the more they will crave grass in an attempt to clear it out. On the other hand, your feline might, eventually, stop eating altogether. Learn what to do if your cat won’t eat.

Note: When they are also vomiting blood, it is possible that they’ve ingested toxins, for example in the form of pesticides or other chemicals found outside. Should this be the case with your kitty, don’t hesitate and take her to the vet immediately!

outdoor brown cat eating grass

Cat eating grass? 3 tips to keep them safe

Even though your cat eating grass on occasion is generally no cause for concern, there are certain steps you should take to ensure your cat’s safety.

1. Beware of pesticides.

If you have a garden which your cat has declared fair hunting ground, make sure it’s a cat-friendly garden:

  • make sure not to use any insecticides or herbicides
  • check for any toxic plants that you might grow there (see below)

2. Provide cat grass at home.

If the whole neighborhood is fair roaming territory for your pet, it gets trickier to avoid pesticides and other dangers; don’t let them eat anything and everything!

A better option to them ingesting potentially harmful substances when they’re out and about, is providing cat grass at home which you know it’s safe to eat.

beige cat eating grass from dish

Cat grass seeds, usually oat, barley or wheat, are available at the pet store. You can also grow it yourself in pots or outside – a five-star gourmet alternative to the greens sprouting next to busy roads or on dog-marked territory.

3. Keep your cat away from toxic plants.

If you keep your cat indoors, make sure you provide them with cat grass as well and remove all toxic plants that they might nibble on instead. Whether your feline spends a lot of time outside or indoors, it’s useful to go through this list of the most common toxic plants:

  • Amaryllis
  • Dieffenbachia (also known as Dumb Cane)
  • Lilies
  • Heartleaf Philodendron (also known as horsehead philodendron)
  • Aloe plant
  • Sago palm

The list goes on, so make sure all your plants are non-toxic to cats before bringing your pet home.

Ingesting toxic plants can induce anything from stomach bleeding to liver failure and death.

What is a good alternative to offer cats eating grass?

So, now that you know why cats eat grass and throw up, you can rest assured, knowing that your kitty is just aiding her own health.

However, being on the safe side is always the best way to go, so check out some other alternatives. A better option is to check your local pet store for cat grass, which is definitely safer and can satisfy your feline’s appetite for grass.

If your kitty has a habit of wandering far from home, looking for snacks, then it’s a good idea to keep track of them with the help of a GPS cat tracker.

Track My Cat

Top reasons why your cat is eating grass

Simply put – cats eat grass because it comes natural to them – an instinct ingrained in them long ago by their ancestors. Eating grass has a number of health benefits, which helps to explain why even our domesticated kitties like to munch on the green plentiful plant.

So, can you now remember the reasons why your cat is eating grass? Discover the summarized answers here:


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