I use Hill's Science Diet. My cat seems to enjoy it. I have tried other brands, but he wouldn't eat them - and starvation is not the answer!

Go to the pet store and ask or look for weight control food. Most of them contain less fat and fewer calories then regular cat food.

I've tried Science Diet and an IAMs weight loss formula, they didn't do anything for my cat. We've started using Nutro's Natural Choice Indoor cat weight control (dry food) and he's looking slimmer already and it's been 3 weeks. He loves it, and doesn't eat as much of it as other foods to feel satisfied. (I free-feed---not always able to be home right on time to feed him!)