If you’re a dog owner, you’ve probably noticed your furry companion snacking on grass from time to time. But why do they do it? Should you be concerned? Is it harmful to their health?
In this article, we’ll explore several possible reasons behind this common canine behaviour. Spoiler alert: it’s not necessarily because they’re feeling under the weather! Let’s clear up that myth straight away.
While some dogs may nibble on grass when they have an upset stomach, the majority do so without any signs of illness. In fact, one of the following explanations could be a much more likely reason behind your dog’s greenery-grazing habits.
1. Instincts from Their Wild Ancestors
One widely accepted theory is that grass-eating is an inherited behaviour from dogs’ wild predecessors. Consider wolves and foxes – these carnivorous hunters consume entire prey animals, including the stomach contents of herbivores.
These contents naturally contain plant matter such as grass. Many experts believe that domesticated dogs have retained some of these ancestral behaviours, meaning that chewing on grass could simply be a remnant of their evolutionary past.
2. Missing Nutrients in Their Diet
Another possibility is that dogs eat grass to make up for certain dietary deficiencies. Just like humans, our four-legged friends require a balance of vitamins and minerals to stay healthy. (Check out our Ultimate Gut Health Guide for more information.)
Dogs may instinctively seek out food sources that contain the nutrients they’re missing – and for some, grass might seem like the answer. However, scientific evidence supporting this theory is limited. The same applies to the idea that dogs eat faeces for similar reasons (a behaviour known as coprophagia – more on that later!).
If you suspect that your dog is eating grass due to a nutritional imbalance, it might be worth assessing their diet or speaking to a vet or canine nutritionist for expert advice.
3. Boredom or Stress
Some dogs may chew grass simply because they’re bored or anxious. Just like humans who fidget, bite their nails, or snack when feeling restless, dogs may find chewing grass to be a soothing activity.
Ensuring your dog gets plenty of physical exercise and mental enrichment can help reduce this behaviour. If your pup is excessively chewing on objects beyond grass, it could be a sign of deeper stress, so consulting a vet or behaviourist may be a good idea.
4. The Taste or Texture
Believe it or not, some dogs may eat grass just because they enjoy it!
For example, some dogs seem more interested in grass when it’s damp, possibly because of the texture or the hydration from water droplets. Just like humans have different food preferences, some dogs may simply find grass appealing to chew on.
5. Feeling Unwell
“Wait a second,” we hear you say. “Didn’t you say it’s not because they’re ill?”
What we actually said is that it’s not necessarily due to illness. Research suggests that fewer than 10% of dogs who eat grass vomit afterwards, meaning that an upset stomach isn’t always the reason.
However, some dog owners report their pets vomiting shortly after eating grass, leading to the belief that dogs do this to self-medicate. While this could be true, there’s little evidence that dogs consciously eat grass to make themselves sick. If your dog frequently vomits after eating grass, it’s best to consult a vet to rule out any digestive issues.
Is Eating Grass Dangerous for Dogs?
In most cases, grass itself isn’t harmful, but there are some risks to be aware of.
Grass treated with pesticides or fertilisers could be toxic to your pet, so it’s essential to monitor where they’re grazing. Additionally, some wild plants and grasses can be hazardous if consumed, so familiarising yourself with potentially dangerous flora in your local area is a good idea. (Check out our Toxic Plants for Dogs guide for more information.)
Why Does My Dog Eat Faeces?
Dogs may engage in coprophagia (poo-eating) for several of the same reasons they eat grass, including:
Instinct: In the wild, mother dogs eat their puppies’ faeces to keep their den clean and reduce scents that might attract predators.
Dietary Deficiencies: Dogs might seek out faeces containing undigested nutrients they lack in their own diet.
Boredom or Attention-Seeking: Some dogs engage in this behaviour simply because they’re under-stimulated or looking for a reaction from their owner.
Hygiene: Some dogs instinctively clean their environment, which is more common in multi-dog households.
It’s also worth noting that dogs have significantly fewer taste buds than humans (1,700 compared to our 9,000), which explains why they often find things appetising that we would consider revolting!
How to Prevent Grass-Eating
If you’re worried about your dog’s habit of munching on grass, there are several things you can try:
✔ Provide a Balanced Diet – Make sure your dog is getting all the necessary nutrients by feeding them high-quality, well-balanced food. (See our Ultimate Nutrition Guide for more details.)
✔ Boost Mental and Physical Stimulation – Regular exercise, training, and interactive toys can help reduce behaviours caused by boredom or anxiety.
✔ Supervise Outdoor Time – Keep an eye on your dog when outside and redirect their attention with toys or treats if they start grazing on grass (or worse!).
✔ Consider Digestive Supplements – If your dog frequently eats faeces, a fibre-rich or probiotic supplement may help address any gut imbalances.
Final Thoughts
Grass-eating is a common dog behaviour, and while it may occasionally indicate an upset stomach, there are plenty of other potential explanations. Nutritional gaps, instinctive tendencies, boredom, or even just preference could all be contributing factors.
Although the idea that dogs eat grass to induce vomiting remains a popular belief, scientific research suggests this isn’t always the case. However, if your dog frequently vomits after consuming grass, it’s always a good idea to seek veterinary advice.
At the end of the day, some dogs just enjoy the taste – and as long as it’s not causing harm, there’s usually no need to worry!
