At the vet today I got some samples of something called Medi-Cal reducing formula. She said it's the only food she has ever heard of that actually causes weight loss, rather than weight control. It wasn't expensive; the big bag is around $30 which is what I pay for the Iams. The vet recommended mixing the medi-cal with the iams (because Bassett needs hairball control food). I brought home the samples and when it's supper time tonight I'm going to give it a try