It’s not because they’re weird. Not just that, anyway.
Many household animals, including cats and dogs, seem to enjoy the taste of grass. Even though they tend to hork it up just a few minutes later, they always seem to come back for more. Why is that?
A survey of over 1000 cat owners showed some possible reasons behind the grass eating obsession. The most common reason that people believe cats eat grass is that it helps them flush their systems when they are feeling ill. But based on this study, 91% of the cats showed no signs of feeling ill before eating grass.
This shows that purging was not the intended objective of the cat. It is an instinctual behavior that comes with an evolutionary benefit to the felines. It has been reported that eating grass helps animals expel intestinal parasites by increasing their muscle activity in the digestive tract.
This research was based on a study of chimps and wild animals. Cats, today, are not commonly fighting off intestinal parasites, but it appears that this behavior stemmed from a distant ancestor. Researchers suggest to cat owners that they buy or grow some indoor grass for the cats to chew on. This way you can be sure that they are not chewing on anything that is poisonous while providing them with an opportunity to participate in this ancestral behavior.
If you see your cat eating grass, you should try to discourage the cat as much as possible, especially since we know the reason behind the grass-feeding frenzy isn’t to make them feel better. In most cases, it is a behavior that they inherited, but with all the chemicals and other substances found on the ground, it is best to avoid eating it all together.