For cats that eat grass, it seems not to be associated with illness or dietary deficiency. One theory is that it is an evolutionary adaption to intestinal parasites and may serve as a purging mechanism. The taste of sweet moist grass may help to explain it as well as there are some observers who think it is more common with new spring grass. —Elizabeth Colleran, DVM, DAVBP (feline practice)
The short answer is we don’t know. Most veterinarians agree grass eating seems to be a way for cat to relieve gastrointestinal (GI) symptoms, parasites or possibly infections. Another theory is that cats are craving micronutrients found in leafy plants. Finally, cats may eat grass simply because they like it. It’s important to remember some cats suffering from inflammatory bowel disease (IBD) may be misdiagnosed as “grass eaters” when the real problem lies within. If your cat is eating grass everyday or large amounts, ask your vet to check out your cat immediately. —Ernie Ward, DVM
