Although grooming is healthy, some cats practice excessive grooming, which can actually cause problems. Skin inflammation, hair loss, or development of hairballs can result from grooming, particularly excessive grooming.
Hairballs can be a serious problem, and are most common in longhaired cats.
Long hair can become knotted and matted, and can only be prevented by regular brushing. This will help control the amount of loose hair the cat leaves deposited around the house as well as minimizing the amount of hair the cat swallows while grooming itself. Hair that is swallowed can form into hairballs in the cat's stomach and intestines. The cat develops a hairball. This condition is rarely dangerous or fatal.