Why does my cat eat litter?

Eating litter, along with plastic, fabric or other non-food items, is called pica, and it has several possible causes rather than one. In kittens it can just be exploratory mouthing that fades with age. In adult cats it is more often linked to a nutrient gap, gastrointestinal discomfort, anemia or a compulsive stress-related behavior, and clumping litter specifically carries a real blockage risk if she is swallowing meaningful amounts rather than the occasional stray granule. Switching to a non-clumping litter temporarily reduces the immediate danger, but it does not address why she started.

When to call a vet: Any cat regularly eating litter needs a vet visit to rule out anemia, GI disease or a nutrient deficiency before this is treated as a habit to just manage.