You're always conscious about your dog's nutrition - you've checked her diet with the vet and you get her healthy snacks (like some homemade Baked Biscuits, maybe), and yet every time you let her out back, she starts chowing down on a bunch of grass. What gives - is this normal or something to be concerned about? Why do dogs eat grass?

WHY DO DOGS EAT GRASS?

Unfortunately, the short answer is that no one knows for sure. While it's quite a common behavior, the reality is that different dogs likely do it for different reasons, and we can't be entirely sure what those are.

That said, there are a lot of educated theories from vets and other qualified professionals, so let's go through some of the likeliest reasons that your pooch may be eating grass.

One common thought is that dogs eat grass to help themselves vomit because of stomach issues. This is actually something commonly seen in cats - they will eat grass, which they can't digest, in order to force themselves to throw up, which in turn clears out anything else in their digestive tract that they may not be able to digest easily.

It's unclear if this is the reason that dogs eat grass, but we do know that even if it is true, it's not the reason behind most grass eating. When this has been studied, it's been found that the majority of grass-eating dogs are not having gastrointestinal issues when they eat grass. There are also many dogs that frequently and repeatedly eat grass, not only when they're not feeling well.

Another likely possibility is that your dog is trying to get nutrients that are lacking in her diet, particularly fiber. There have been some cases in which owners have reportedly switched their dogs to high-fiber diets and seen them stop eating grass as a result, but there isn't enough evidence to be sure that this is actually what's happening.

One last idea is that dogs may just eat grass because they like it. Think about it like humans chewing bubble gum - it doesn't fulfill any nutritional need, but we do it anyway because we enjoy the texture of it (and, of course, blowing bubbles). Just like your dogs like chew toys and eating your shoes, they may enjoy the feeling of eating grass.

This is doubly true if they're bored and looking for something to do. We've all seen videos of what bored dogs can do when left at home - from labs chewing through doors to huskies pulling every last piece of stuffing out of couches. When dogs have too much energy and aren't getting enough stimulation, they often find ways to entertain themselves with their mouths, so eating grass shouldn't be too much of a surprise.

IS IT OKAY FOR DOGS TO EAT GRASS?

Many people think of dogs as carnivores, but it's important to remember that that's actually not the case - they're omnivores, which is why you'll often find things like rice in your dog's kibble. Thus, the fact that they're eating grass isn't necessarily something that you need to be worried about. While it's not a particularly nutritious food, there's nothing inherently problematic or dangerous about grass.

While we don't recommend using your dog as a living lawn mower, you don't need to fearful of a little bit of grass eating, nor should you feel the need to stop your dog every time you see it happening. 

That said, there are a couple of exceptions. First, grass itself is fine, but things like weed killer and pesticides are definitely not. If your grass or other nearby plants are being treated with anything that's potentially poisonous or toxic, it's important to keep your dog away. 

Also, if in addition to your dog's grass eating, you're also noticing other changes in behavior related to eating or gastrointestinal healthy, you should make note of these and consult with your vet. This could be things like eating a lot of grass while ignoring the food that you're providing for meals, as well as eating grass and vomiting afterwards frequently. 

MY DOG IS EATING GRASS AND VOMITING

As mentioned, this is not entirely uncommon, and it's possible that your dog vomits after eating grass because he wasn't feeling well in the first place. If this is happening once in a rare while, it's not something to be deeply concerned about. On the other hand, if your dog is eating grass and then vomiting frequently (or really if you dog is vomiting frequently under any conditions), you should definitely take him into the vet to get checked out. 

HOW DO I STOP MY DOG FROM EATING GRASS?

Whether you're worried about your dog's health or annoyed that your prize-winning lawn is uneven because of the grass munching, there are a few ways to get your dog to stop eating grass.

First, limit your dog's exposure to grass. If she's staying in your backyard all day with nothing to do, she's liable to start eating grass, so if you can keep her inside or elsewhere, that will certainly help to curb the behavior. You may also find that there are particular areas of your lawn that your dog likes to eat, and in those cases, simply fencing off those areas or using other methods to keep your dog away may help to resolve the issue.

Second, use training and redirection. If your dog likes to grab a nibble of grass here and there while you're out on a walk, redirect her away from that behavior and offer a treat when she listens. 

Lastly, try adjusting your dog's diet. While we can't be sure that a lack of fiber is the cause, there is anecdotal evidence that it may play a part in some grass eating. In those cases, it may be worth trying to switch your dog to a diet that is higher in fiber to see if that helps to change the behavior. It's always a good idea to talk to your vet before changing your dog's diet, and when you do switch over to a new food, do it slowly, starting with a mix of the old and new foods, and slowly changing the mix to have more and more of the new food until it's fully switched.