Why is my dog eating grass?

Has your dog started eating grass recently?

Don’t panic!

The old wives tale that it is because your dog is unwell, might not be so true.

Eating grass, especially that lush spring grass that has started shooting about now, is normal canine behaviour.  I’m sorry to disappoint you all, I know how much you love pulling stringy bits of grass for your dog’s bum.

I think we often forget that dogs are omnivores and opportunistic scavengers.  A survey by Hart et al. (2008) of 1500 dog owners noted that nearly 68% of owners claimed their dogs ate plant matter daily to once a week.  Of those dogs, only 8% were reported by their owners to look frequently ill beforehand.

‘So, why then?’ you might ask.  There could be a couple reasons.

During the spring, the rapid growth of the grass leaves it high in sugars, specifically known as water soluble carbohydrates or WSCs.  These peak during certain times of the day, namely early morning and late in the afternoon.  The dew that accumulates on grass also plays a role in aiding protein hydrolysation, meaning breaking those proteins down into smaller, more digestible molecules. 

That means one reason dogs eat grass, is it tastes nice and is easier to digest as a fibre source. 

Grass also has a high water content and dogs, especially in the warmer months or after high activity, are consuming grass for hydration.

Hart et al (2008) also hypothesised that grass eating could be an act of “purging of intestinal parasites” as observed in wild canids. 

When is it not normal?

Grass eating, with no other signs of illness, can be considered normal, even if it looks a little more frantic than a cow mowing in a field.  Dogs aren’t built to look majestic while eating grass.  However, if you’re seeing an excessive amount of grass consuming, alongside other signs of illness or discomfort, it might be time to go to the vet.

Lulu, for example, will sometimes ask to go out in the garden and start chowing down on grass with single-minded determination.  She will sometimes then regurgitate the grass, along with part of a chew that has not digested properly.  Other times she will eat grass and go off her food, clearly a sign of an upset stomach than the casual chomps I see my other dogs partake in on a walk.

In short, grass eating isn’t something to worry about unless you are observing other issues.  It is also worth noting that if your dog does like to munch on grass on the regular, you keep track of internal parasite control in case they also ingest any eggs or other nasties.