If you're a dog owner, you've probably noticed your furry friend munching on grass every now and then. At first, it might seem odd—after all, aren’t dogs primarily carnivores? This common behaviour has puzzled dog lovers for decades, sparking a flurry of questions like, “Why will a dog eat grass?” and “Is it something I should worry about?”

While the sight of your dog eating grass occasionally can be perplexing, the truth behind this behaviour isn’t as alarming as it might seem. From satisfying dietary needs to alleviating an upset stomach, there are several reasons why dogs eat grass. Below, we unpack the potential causes, whether it's harmful, and what steps you can take to stop your dog from eating grass excessively.

Why Do Dogs Eat Grass?

A Throwback to Their Ancestors

Dogs may eat grass due to their evolutionary lineage. Their wild ancestors, like wolves and other canids, were not just meat eaters but opportunistic omnivores. This means they consumed the entire animal they hunted, including plant material found in the stomach contents of their prey. Grass and other plant materials made up a small portion of their diet, providing essential nutrients and fibre.

While modern dog food offers a complete and balanced diet for most dogs, this evolutionary behaviour may still linger. Some experts suggest that many dogs instinctively consume grass as part of their natural foraging habits.

Nutritional Deficiencies

One widely held belief is that dogs eat grass due to a dietary deficiency. If your dog’s diet lacks an essential nutrient—such as fibre, vitamins, or minerals—they might instinctively resort to eating grass to make up for the shortfall.

Though most commercial dog foods are designed to be nutritionally complete, younger dogs or those fed an imbalanced diet might still develop such deficiencies. Adding more fibre or consulting your vet to ensure your dog’s diet provides all necessary nutrients could help.

To Soothe an Upset Stomach

It’s commonly thought that dogs eat grass to relieve an upset stomach. Grass eating might encourage vomiting, helping dogs pass undigested food or clear their digestive system of irritants.

If your dog is eating grass and vomiting within a few hours, this could indicate that their stomach contents are causing discomfort. However, if this becomes a repeated behaviour, it’s important to consult your vet—it could point to a larger gastrointestinal disease or underlying health issue.

Grass Eating for Taste or Boredom

Another simple reason dogs may eat grass is that they enjoy the taste or texture. Certain types of grass might appeal to your dog’s palate, much like we might crave specific snacks. Boredom is another potential cause—when dogs don’t receive sufficient mental stimulation, they may turn to grass eating as a way to pass time.

If you have a bored dog or one that’s repeatedly eating grass, increasing exercise or introducing puzzle toys might help channel their energy elsewhere.

Is Eating Grass Harmful to Dogs?

For most dogs, eating grass occasionally is not harmful. It’s generally considered a normal behaviour in healthy dogs. However, there are a few risks to be aware of:

1. Pesticides and Lawn Chemicals

Grass treated with harmful chemicals, such as pesticides or fertilisers, can pose dangers to your dog’s health. If your dog is eating grass, ensure your lawn is free from toxic substances.

2. Intestinal Parasites

While less common, parasites from contaminated grass or soil can affect your dog's health. Regular deworming and annual check-ups with your vet are essential to prevent this.

3. Choking or Obstruction

Dogs that consume too much grass at once might struggle to swallow or digest large amounts, which can lead to a blockage.

To put your mind at ease, keep an eye on your dog’s behaviour. If they’re showing signs of being sick or eating grass in larger quantities while looking unwell, it’s a good idea to contact your vet for advice.

How to Stop Your Dog From Eating Grass

If your dog’s grass-eating habits are excessive or concerning, there are steps you can take to prevent it. Here’s how:

Step 1: Evaluate Their Diet

First, make sure your dog is receiving a nutritionally complete and balanced diet. Consult your vet to confirm your dog’s food contains all essential nutrients, including enough fibre. If your dog is fed homemade meals, ask your vet whether you need to add a fibre-rich or essential nutrient supplement.

Step 2: Provide More Mental Stimulation

Boredom is a common trigger for grass eating. Engage your pet with toys, games, and plenty of physical exercise to keep their mind and body active. Puzzle feeders, interactive toys, and training sessions can all help alleviate boredom.

Step 3: Monitor Their Grass Access

If your dog is eating grass in your backyard, pay attention to the type of grass they’re consuming. Try to prevent access to treated lawns or unfamiliar grassy areas during walks. Supervising outdoor playtime can stop them from eating harmful plants or chemicals.

Step 4: Add Taste Deterrents

Some products, such as bitter sprays, can be applied to grass to discourage chewing. These are safe for lawns but deter dogs from nibbling on them.

Step 5: Watch for Signs of Sickness

Monitor your dog closely. If they’re vomiting frequently, have diarrhoea, or are losing weight, consult a vet immediately. Repeated grass eating could signal an underlying illness related to their digestive system or intestinal parasites.

Step 6: Offer Safe Alternatives

If your dog eats grass for its crunchiness or taste, ensure they have alternative chews or veggies like carrots to satisfy these cravings in a healthier way.

What If My Dog Continues Eating Grass?

While grass eating is a common behaviour among dogs, if your dog is eating grass excessively—especially with signs of illness or discomfort—it’s crucial to consult your vet to rule out any health concerns. Some dogs may eat grass as a result of an underlying health issue, like a gastrointestinal disease or a specific nutritional deficiency, requiring immediate attention.

Final Thoughts

Dogs eat grass for many reasons—sometimes out of instinct, sometimes for taste, and other times as a response to stomach discomfort or boredom. For most dogs, this behaviour is completely normal and harmless, provided it doesn’t involve risks like harmful chemicals or excessive vomiting.

As responsible dog owners, staying vigilant about your dog’s overall health and diet is key. Make sure your furry friend is on a balanced diet, gets plenty of exercise, and sees the vet regularly.

If your dog’s grass-eating habits still leave you puzzled, a quick visit to your local vet can provide tailored advice. After all, a happy and healthy dog makes for a happy owner!