My cat is gaining weight or not losing weight, even with a special diet or less food, how is this possible?

When your cat, despite dieting, is not losing weight or even gaining weight, it is important to check if your cat can overeat. Is it possible that your cat is eating more somewhere else (i.e. an outdoor cat). Is clear who of the owners feeds your cat? Is it possible that multiple owners feed your cat, without knowing? Making rules and clear agreements is very important. Another common mistake is that the daily recommended amount is seen as a portion and is fed multiple times a day.