How does the size of a cat affect how food it eats?

Larger animals of the same species expend more energy than smaller animals of the same type. To get the energy their bodies need, the larger animals eat more food.

If i let a 80 pound cat and a 40 pound cat eat as much as food as they want, then the 80 pound cat will eat more than an 40 pound cat. This is because the bigger their body is the more energy they need.