Adult cats, depending on breed, should require around 600 calories per day. Check the label on your commercial cat food for recommendations on how much to feed your cat or kitten.
If you leave dry food out and your cat eats much more than the recommendation on the commercial cat food packaging, then your cat may have a health issue.
Common reasons for cats to over eat are worm infestations, when last have you de-wormed your cat? (Cats should be de wormed regularly)
If your cat is eating too much food and it is not worms, then you need to ask your vet to examine your cat.
