If a cat suddenly loses weight, it could be due to parasites. If the cat is infected with internal parasites such as roundworms or tapeworms, these parasites will steal nutrients from the cat, causing it to be unable to absorb enough nutrition even if it eats a lot, thus becoming increasingly thin. The cat may also experience symptoms such as diarrhea.
In addition, if a cat's diet is too monotonous, or if it eats poor-quality cat food for a long time, resulting in an unbalanced diet and a lack of essential nutrients, it may lead to malnutrition and emaciation.
