There's no such thing as "weight control" (dry) cat food except on food packaging by the crooked pet food business. The stuff invariably is full of carb, which cats do not metabolize like we do (they get their glucose through gluconeogenesis, from meat) and it's far too dry (cats on a normal diet gets the bulk of their water from "wet" food, and get much less water when on dry food, leading to kidney stones and bladder problems).

Cats are true carnivores. They shouldn't be getting dry food to begin with.