Why Do Dogs Eat Grass? Getting to the Guts of the Problem

Have you ever watched your dog stop mid-walk to munch on grass and wondered why?

For some dogs, it's an occasional habit. For others, it's a daily ritual. While grass eating is incredibly common, it's often misunderstood. Many people assume dogs only eat grass when they feel sick, but the reality is far more complex.

Sometimes grass eating is completely normal. Other times, it can be a clue that your dog's digestive system, diet, or gut health needs attention.

Understanding the "why" behind the behaviour can help you support your dog's health more effectively.

Is It Normal for Dogs to Eat Grass?

In many cases, yes.

Dogs have been consuming plant material for thousands of years. Although they are primarily carnivorous scavengers, wild canines regularly ingest grasses, berries, roots, herbs, and the stomach contents of prey animals.

Many modern dogs simply enjoy the taste, texture, or smell of fresh grass. Some like the crunch, while others seem to enjoy grazing on young, tender shoots during certain seasons.

If your dog occasionally nibbles on grass, appears healthy, has normal bowel movements, and shows no other signs of illness, there's usually no reason for concern.

The Different Reasons Dogs Eat Grass

1. They Simply Enjoy It

Just like some dogs love chewing sticks, digging holes, or rolling in the grass, some genuinely enjoy eating it.

For many dogs, grass is simply another interesting part of their environment.

2. Instinct and Natural Behaviour

Plant material has always formed part of a canine's natural diet.

Wild dogs and wolves consume vegetation both directly and indirectly through their prey. This instinctive behaviour remains deeply ingrained in many dogs today.

3. They May Be Looking for Fresh Plant Nutrients

This is one of the most overlooked reasons dogs eat grass.

Fresh plants contain valuable phytonutrients, antioxidants, enzymes, chlorophyll, fibre, and other naturally occurring compounds that support health and wellbeing.

Many dogs today are fed predominantly dry, highly processed diets. While these foods may meet basic nutritional requirements, processing can significantly reduce the naturally occurring enzymes and plant compounds found in fresh foods.

As a result, some dogs may instinctively seek out grass, herbs, weeds, or other vegetation as a way of obtaining nutrients that are lacking in their diet.

This may be particularly relevant for dogs eating exclusively kibble-based diets with little fresh food included.

Adding fresh, species-appropriate foods such as leafy greens, sprouts, herbs, and nutrient-dense vegetables can often help provide a broader spectrum of naturally nutrients and phytonutrients.

4. They're Seeking Additional Fibre

Grass contains fibre, which helps support healthy digestion and bowel function.

Some dogs may instinctively seek fibre-rich plant material when their digestive system is out of balance or when they need additional roughage in their diet.

5. Boredom or Stress

For some dogs, grass eating can become a behavioural habit.

Dogs that are under or over stimulated, anxious, or lacking enrichment, may chew grass simply because it provides sensory stimulation or helps them self-soothe.

6. Digestive Discomfort

While not every grass-eating dog has digestive issues, for some there is indeed a connection between increased grass eating and digestive discomfort.

Grass eating isn't always random. In some dogs, it may be one of the body's subtle ways of responding to digestive upset.

Poor digestion, food sensitivities, gut microbiome imbalances, low stomach acid, inflammation, nutrient malabsorption and certain pharmaceutical drugs can all contribute to feelings of discomfort.

When digestion isn't functioning optimally, dogs may experience:

• Nausea
• Excessive gas
• Bloating
• Acid reflux
• Audible stomach gurgling
• Intermittent vomiting
• Loose stools
• Changes in appetite

Some dogs instinctively turn to grass during these periods, particularly if it provides temporary relief or helps stimulate digestion.

The Gut Connection

Your dog's gut is responsible for far more than simply digesting food.

A healthy digestive system is essential for nutrient absorption, immune function, detoxification, and overall wellbeing. It's also closely connected to psychological health and behaviour through the gut-brain axis, which links the digestive system with the nervous system. When gut health becomes compromised, dogs may experience not only digestive symptoms but also changes in mood, stress levels, behaviour, and eating habits, including an increased desire to eat grass. One common issue is inadequate enzyme activity.

Digestive enzymes help break down proteins, fats, and carbohydrates into smaller nutrients that can be absorbed and used by the body. When food isn't properly digested, it can ferment in the digestive tract, contributing to gas, bloating, irritation, and nutrient deficiencies.

Supporting digestive function often helps address the root cause rather than simply managing the symptom.

When Grass Eating May Not Be Normal

While occasional grazing is usually harmless, excessive or sudden grass eating deserves closer attention.

You may want to investigate further if your dog:

• Suddenly starts eating large amounts of grass

• Eats dry dying grass

• Eats grass obsessively every day

• Vomits frequently after eating grass

• Has diarrhoea or constipation

• Experiences excessive gas or bloating

• Has noticeable stomach gurgling or digestive noises

• Shows signs of nausea or lip licking

• Has a reduced appetite

• Appears lethargic or uncomfortable

• Eats dirt, rocks, sticks, or other non-food items

These signs can indicate underlying digestive dysfunction, food intolerances, microbiome imbalances, parasites, or nutritional deficiencies that should be addressed.

Supporting Dogs That Frequently Eat Grass

If your dog regularly seeks out grass, it's worth looking beyond the behaviour itself and considering what may be driving it.

Improve Dietary Variety

Adding a diverse range of fresh whole foods to your dog's diet can provide important nutrients that may be lacking in heavily processed foods.

Fresh greens, herbs, sprouts, vegetables, and other nutrient-rich foods can help increase dietary diversity and provide valuable phytonutrients that support overall health.

For palatability, you can pulp vegetables in a food processor or lightly cook, steam or sauté, and mix through meat or other foods. Even better, you can feed fermented vegetables.

Support Digestive Function

For dogs showing signs of digestive discomfort, targeted gut support can make a significant difference.

At Aussie Pooch, we often recommend supporting digestion with digestive enzymes, probiotics, prebiotics, and gut-healing herbs.

Digestive Reset

Digestive Reset is designed for dogs experiencing acute digestive upset or significant gut imbalances.

It contains digestive enzymes alongside gut-supportive ingredients that help improve food breakdown, support nutrient absorption, soothe the digestive tract, and assist in restoring microbiome balance.

It can be particularly beneficial for dogs experiencing:

• Grass eating associated with digestive discomfort

• Bloating

• Gas

• Loose stools

• Digestive upset including vomiting and diarrhea

• Gut dysbiosis

Get Digestive Reset here 

Digestive Care

For dogs requiring longer-term digestive support, Digestive Care helps maintain healthy digestion and gut function on an ongoing basis.

Containing digestive enzymes and ingredients that support a balanced microbiome, it is ideal for dogs with chronic digestive sensitivities, recurring tummy troubles, or ongoing gut health challenges.

By improving digestion and nutrient absorption, many dogs naturally become less interested in eating grass because their nutritional and digestive needs are being met more effectively.

Get Digestive Care here

The Gut Takeaway

Grass eating isn't necessarily a problem.

For many dogs, it's a normal behaviour driven by instinct, enjoyment, or a desire for fresh plant matter. However, when grass eating becomes frequent, obsessive, or is accompanied by digestive symptoms, it's worth considering what your dog may be trying to communicate.

Sometimes they're looking for fresh phytonutrients missing from a processed diet. Sometimes they're seeking additional fibre. And sometimes they're experiencing digestive discomfort linked to poor digestion, gut imbalances, or nutrient malabsorption.

Rather than simply trying to stop the behaviour, focus on supporting the whole dog. A fresh, nutrient-rich diet combined with good digestive health can go a long way toward helping your dog feel their best—from the inside out.

References

Sueda, K.L.C., Hart, B.L., & Cliff, K.D. (2008). Characterisation of plant eating in dogs. Applied Animal Behaviour Science, 111(1–2), 120–132. This landmark study found that grass eating is common in dogs and is generally not associated with illness, vomiting, or dietary deficiencies.

Bjone, S.J., Brown, W.Y., & Price, I.R. (2007). Grass eating patterns in the domestic dog (Canis familiaris). Recent Advances in Animal Nutrition in Australia, 16, 45–49. This study found that grass eating appears to be a normal canine behaviour and may be influenced by feeding patterns and satiety.

McKenzie, S.J., Brown, W.Y., & Price, I.R. (2010). Reduction in grass eating behaviours in the domestic dog: The impact of dietary and gastrointestinal factors. Applied Animal Behaviour Science, 126(1–2), 42–47. This research further explored the relationship between digestive health and grass-eating behaviour.

Cryan, J.F., O'Riordan, K.J., Cowan, C.S.M., et al. (2019). The Microbiota-Gut-Brain Axis. Physiological Reviews, 99(4), 1877–2013.

Garcia-Mazcorro, J.F., Barcenas-Walls, J.R., Suchodolski, J.S., & Steiner, J.M. (2021). The microbiome-gut-brain axis in companion animals. Frontiers in Veterinary Science.

Disclaimer: While grass eating is considered a normal behaviour in many dogs, excessive grass consumption or grass eating accompanied by other symptoms may warrant veterinary investigation. Research into the exact reasons dogs eat grass is ongoing, and multiple factors—including instinct, diet, digestive health, and behaviour—may contribute.