Randi, sounds like everyone has listed what I could think of and more besides. Thyroid is the biggy for aging cats. There are "rumors" among some cat forums that Science Diet may actually contribute to it. That would be the regular kibble. The rumors were the reason I looked into foods in January and then based on my research I changed food after 12 years.

Oh Gary, "kittyzens" for the senior cats? I LOVE it!