Why Do Dogs Eat Grass? A Look at a Common Doggie Habit

Ever caught your dog munching on the lawn like it’s an all-you-can-eat salad bar? If you’re a dog owner, you’ve probably seen this quirky behaviour at least once. One minute they’re sniffing around, and the next they’re happily eating grass. It might leave you scratching your head and wondering: “Why do dogs eat grass, and should I be worried?” Don’t worry, you’re not alone in asking this question. Let’s dig into some reasons behind this grass-grazing habit in a friendly, conversational way.

Is It Normal for Dogs to Eat Grass?

In most cases, yes, chowing down on grass is actually pretty normal dog behaviour. Many vets and experts consider it a common habit, not necessarily a sign that anything’s wrong. One small study found that only about 22% of dogs vomited after eating grass, and only 9% showed signs of illness beforehand. So the majority of dogs weren’t sick before or after their salad buffet. The researchers concluded that plant-eating, including grass, is a normal behaviour in domestic dogs.

It’s not just our pet dogs, either. Wild canines do it too. Observations of wolves found that up to 10% of their stomach contents can be plant material. So your dog’s grass habit could just be an echo of their ancestry, a little instinct passed down from their wild relatives.

Possible Reasons Why Dogs Eat Grass

So why do dogs treat your garden like a salad bar? Here are some of the most common theories:

It Tastes Good
Believe it or not, some dogs just like the taste and texture of grass. Especially when it’s fresh and dewy, it might be a refreshing little snack.

Ancestral Instinct
Dogs are omnivores by ancestry. Wild canines eat whole prey, fur, organs, and yes, even the plant-filled contents of their prey’s stomach. Eating a bit of greenery might just be hardwired into their behaviour.

Seeking Fibre or Nutrients
Grass is full of fibre. Some dogs may eat it to help with digestion. There was even a case of a dog whose grass-eating stopped when it was switched to a high-fibre diet. If your dog’s meals are nutritionally sound, this probably isn’t the issue, but worth keeping in mind.

Upset Tummy or Self-Medication
Some people think dogs eat grass to make themselves vomit if they have an upset stomach. Research suggests this might be true sometimes, but most grass-eating dogs don’t actually vomit. Still, some dogs may eat grass first thing in the morning and then be sick. It’s possibly a way for them to relieve stomach acid.

Boredom or Enjoyment
Sometimes it’s just something to do. Especially in the garden or on a slow walk, dogs might eat grass out of boredom, curiosity, or playfulness.

Attention-Seeking
If your dog notices that eating grass gets your attention, they might do it more. Whether it’s you shouting across the garden or running over with a treat, dogs are clever – and might use grass to press your buttons.

Worming Themselves or Response to Discomfort
There are some theories that grass might help purge parasites, or that dogs eat it in response to mild pain or stress. These are less proven but worth noting if the behaviour becomes obsessive or changes suddenly.

Should You Worry If Your Dog Eats Grass?

Most of the time, a bit of casual grazing is fine. But there are a few things to watch out for:

Chemicals on the Grass
Make sure your dog isn’t eating grass that’s been sprayed with pesticides, weedkiller, or fertiliser. These can be toxic. If you’re unsure, keep them away from treated areas.

Parasites and Germs
Grass can harbour parasites or bacteria from other animals. This is more of a risk in shared spaces like parks. Keep up to date with worming and vaccinations if your dog’s a grazer.

Tummy Upset or Vomiting
Some dogs vomit after eating grass, especially if they eat it quickly or in large amounts. If they’re sick once and then fine, it’s probably not a big deal. But if it keeps happening, speak to your vet.

Other Symptoms
If your dog is eating grass and also off their food, drinking less, vomiting repeatedly, has diarrhoea, or is acting strangely, don’t wait, give your vet a ring.

Compulsive Behaviour
If the grass eating becomes obsessive or increases suddenly, especially alongside changes in appetite or energy, that could signal an issue worth investigating.

Final Thoughts (and a Friendly Disclaimer)

Dogs are funny creatures. Sometimes they do things we just don’t understand, and eating grass is one of those odd but mostly harmless behaviours. Your dog might be following a centuries-old instinct, managing a bit of indigestion, or just finding it tasty.

That said, always pay attention to the context. If the grass eating is paired with worrying symptoms, or if you’re ever in doubt, it’s best to contact your vet.

Disclaimer: We’re not vets,  just dog people. Everything here is based on research and shared experience, but it’s not medical advice. If you’re concerned about your dog’s behaviour or health, always speak to a veterinary professional. It’s better to be safe than sorry.

References

1. Karen Sueda, Benjamin Hart, Kelly Cliff – Survey on grass-eating behaviour in domestic dogs

2. American Kennel Club – Why Do Dogs Eat Grass?

3. Blue Cross – Common questions about dogs and diet

4. AKC Chief Veterinary Officer – Grass-eating and bile

5. Veterinary Manual – Plant-eating behaviour in animals

6. Cummings School of Veterinary Medicine, Tufts University – Nutrition and foraging

7. Journal of Veterinary Behavior – Plant eating in domestic dogs

8. ASPCA Animal Poison Control – Hazards in grass and gardens

9. WebMD Pets – Dog digestion and behaviour

10. British Veterinary Association – Canine foraging and common myths