Hi, former vet tech here. If you're trying to get your cats to lose some weight, ideally they should be on a food geared for weight loss. This is because all their daily macro and micronutrients are calculated into the kibble; so on a regular food, if you're only giving them say 80% of their recommended intake, they're only getting 80% of the nutrients they need. Diet foods are designed to give them all their nutrients and are less calorically dense, which will help with the weight loss. I usually recommend that cats eat a mix of wet food and kibbles. Since cats are desert animals, they often don't drink enough water on their own. Most cats really enjoy wet food, and it helps keep their kidneys healthy. It can also help with weight loss because it keeps them feeling full