Dogs need roughage in their diets and grass is a good source of fiber. A lack of roughage affects the dog's ability to digest food and pass stool, so grass may actually help their bodily functions run more smoothly.

Do dogs eat grass to settle their stomach?

Most vets agree that eating grass probably helps soothe a dog's upset stomach. ... In dogs, eating grass may have the same effect in acting as a 'natural antacid'. Most dogs appear to feel better after eating grass, but this relief is often temporary as most dogs vomit afterwards.

What causes a dog to eat grass?

Bored, Stressed or Upset

Some vets believe dogs eat grass because they're bored, stressed, anxious, or upset about something. Some dogs are more likely to eat grass when they believe they're alone in the backyard, which contributes to the idea that they are unhappy when they do so.