I used to feed my cats Purina Overweight Management, but my vet quit carrying it. They recommended I try the Royal Canine Calorie Control. The cats had no trouble switching to the new food - no upset stomach, always cleaned the bowl (there's a reason they are on calorie control food!). The large bag is less expensive and lasts longer. Other than the one time the vet tried to give me dog food instead of cat food (lol), we've had no trouble with this food. And each kitty lost a pound!

Pros: cats love it, controls weight

Cons: strange odor

The vet told me my cat needed to lose some weight and suggested that I get calorie control cat food. At first she turned her nose up at it but she eventually started eating it and has lost several pounds already.

Pros: Good for overweight cat weight control

Cons: none

Our vet recommended this food for out 2 cats. They were both a little overweight. They each lost about 2 lbs in a year. Our vet said she would be happy if they lost 1 lb in a year. They like it and are happy.

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[updated on 2009-03-13 19:51:01 GMT]:
Our Vetinary suggested this for our 2 cats because they were slightly overweight. The goal was to lose one lb a yr. They both lost about 2 lbs in one yr, so we are very pleased. The cats love it.
Lucille

Pros: Helps our cats maintain healthy weight

Cons: Kinda expensive

When Guiness began his weight loss journey, this was one of the food for fat cats. He had no problem this helped, we had to switch him to a low phs formula cat food.

Pros: Guiness ate this.

Cons: none