I feed my cats the same amounts every day (Remy gets a handful of dry food twice a day (right now he's getting Iams because he goes through phases where he gets sick of the dry food I give him), Flora gets half a handful of dry food and a Sheba Perfect Portion tray twice a day, and Maisie gets a can of Fancy Feast (3oz) in the morning and Friskies (5oz) in the evening). None of them are overweight, but Maisie (who avoids people as much as possible) comes and sits by me when she wants her dinner and it's been happening earlier and earlier every day. She's even resorted to what I call "rage-eating" dry food because she will not eat dry food unless she is desperate. How do I know if she's getting enough to eat? I know Remy and Flora also snack on Maisie's food when she's done, but that's never really been a problem.