Why Does My Dog Eat Grass?

08 Nov, 2019 by Sylvia

Does your canine stop to nibble at grass when you’re walking him or when he’s out playing in the garden? Perhaps you’re worried that he’s sick, or that his stomach is upset. Or maybe you’re just curious about why your dog might want to eat grass, when you’re giving him perfectly good — not to mention expensive — dog food.

Why Does My Dog Eat Grass? Should I Be Alarmed at This Behaviour?

Staffordshire bull terrier eating grass

There is no need to be alarmed when your dog eats grass. Eating grass is a perfectly normal dog behaviour, according to scientific research carried out by a group at the University of California, Davis and published in a journal known as Applied Animal Behavior Science in 2008. This study was conducted because a team of researchers decided to determine whether dogs were eating plant material, particularly grass, due to illness or dietary deficiency. Their findings should be reassuring to dog owners who have noticed their canines munching on grass, whether it be occasionally or on a regular basis.

What the researchers discovered: The vast majority of dogs do eat grass. The frequency of their grass-eating indulgences vary; sometimes dogs only eat grass infrequently, while some eat it weekly or even daily.

Do Dogs Eat Grass Because of an Upset Stomach?

The researchers found that, most of the time, the grass-eating behaviour did not coincide with an incidence of illness or vomiting. Their conclusion was that sickness wasn’t the reason that most dogs eat grass.

So Why Does My Dog Eat Grass If It Isn’t an Illness?

Dogs eat grass

This particular group of researchers couldn’t find any compelling reason to conclude that dogs are eating grass in hopes of compensating for a nutritional deficiency. Some of the dogs in their research group had diets that included plant material including vegetables and / or fruit – and these dogs proved to be just as likely to eat grass as the other dogs who did not.

However, there’s a documented case of a poodle who would eat grass and then vomit daily. This continued for 7 years. When the case was referred to a veterinarian, the vet advised the dog owner to discontinue the dog’s previous diet and try a high fibre diet instead. The high fibre diet resolved the dog’s grass eating and vomiting behaviours.

So, in some cases, it is possible that dogs who eat grass may be in need of more roughage in the diet.

The UC Davis researchers noted another possibility based on the behaviours of Latvian wolves, Greek wolves and North American timberwolves. It is not uncommon to find blades of grass wrapped around parasitic worms that are present in wolf poop. It is possible that wolves might choose to graze on grass as a means of purging intestinal parasites from their bodies. It is also possible that dogs might indulge in behaviours similar to that of these wild ancestors. Perhaps eating grass is an instinctive dog behaviour that could help to prevent the accumulation of parasites in the intestinal tract.

Another obvious possibility is that maybe some dogs just enjoy the taste of grass, the way it makes them feel or the overall effect it has on their bodies.

Eating Plain Grass Is Safe for a Dog – but Weed Killer Is Not

spraying pesticide with portable sprayer to eradicate garden wee

Dogs are omnivorous creatures. Omnivores can consume both plant materials and meats. There is no obvious biological reason why dogs shouldn’t consume grass when the inclination strikes them. Bottom line, there is no need to be alarmed when your dog eats grass.

However, you do need to ensure your dog avoids eating grass that has been sprayed with toxic chemicals such as herbicides or pesticides. You should also ensure that your dog isn’t grazing on any plants that are toxic to dogs such as cyclamen or English Ivy. If your dog accidentally ingests any of these, seek help from your veterinarian immediately.


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