Why do dogs eat grass?

It’s a common misconception amongst dog owners that if your dog eats grass it’s because they feel unwell and are about to vomit. Some people even think it’s because the dogs are missing something from their diet – such as important nutrients. But both of these are in fact myths, says PSDA veterinary nurse Shauna Walsh.

Why do dogs eat grass?

Dogs are omnivores, meaning they eat both meat and plants. Eating grass is completely normal behaviour for dogs, and some choose to snack on it simply because they enjoy the taste.

You may find your dog is particularly interested in a specific grassy spot, sniffing, licking and eating the grass blades. The chances are this will be because there is a really interesting scent left behind, most likely from another animal. It might not sound appetising to us, but another animal’s scent definitely is for dogs.

Another reason your dog might be eating grass is because they are bored, in which case you may wish to look into what you can do to prevent boredom - maybe going for longer, or more frequent walks in different places, playing with them both indoors and outdoors, or by providing games for mental stimulation such as a food puzzle.

There’s usually no need to worry if your dog is eating grass, as it isn’t linked to health issues or dietary deficiencies. However, if your dog appears unwell, eats grass excessively, or only wants to eat grass (and not their usual food), you should seek advice from your vet.

Even though it’s perfectly normal for your dog to eat grass, there are some things to be aware of, such as harmful grass seeds and lungworm.

How to make sure the grass is safe for your dog to eat

Check the grass

You should keep your dog well away from grass that has been treated with fertilisers, herbicides or pesticides as these can be very harmful to your pooch. Also make sure they’re not going to nibble on any other greenery or flowers, which could be poisonous.

Lungworm

Lungworm can be passed on by slugs and snails found in grass. Make sure your dog’s de-worming products include lungworm protection. There are many different products on the market – speak to your vet for advice about which one is best for your dog. Be aware that parasite products bought from a pet shop or pharmacy without a prescription are unlikely to contain lungworm protection.

Grass seeds

You’ll also need to be careful of grass seeds found in long grass, particularly in the summer months. Grass seeds can get stuck in eyes, ears, skin and paws and cause problems for your dog. If you think your dog has a grass seed stuck somewhere, contact your vet. The sooner you get it removed, the less of a problem it’s likely to cause.

Keep the grass short

There is a small risk that long blades of grass can get stuck in the nose and throat causing irritation – try and avoid your dog eating long blades, or keep the grass trimmed short to reduce this risk.

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About the PDSA

The PDSA is the UK's leading vet charity, providing free and low-cost treatment to pets in need. PDSA vets and vet nurses provide veterinary care and advice to sick and injured pets whose owners otherwise couldn’t afford to pay the full cost of treatment.

Why do dogs eat grass?