I have a 13 year old Chihuahua diagnosed at 1 year with Addison's disease which is remedied with steroids. As you can imagine, he's bulky and has always had a weight problem. After being prescribed this food (and a lot of exercise) he has lost nearly 2 lbs off his 9 lb frame and is spunkier than ever. I know the food is a key factor. I feel it has helped his joints, coat, and system in general (very regular pooper!) Can't go without this food and was happy to finally find it available, although I am paying DOUBLE what I used to pay at our old vet (we moved cities) I will pay it for my boy!