I would talk to your vet. If this has been going on for a long time, such a poor diet could be taking its toll. While the sticky at http://www.askmehelpdesk.com/dogs/in...tml#post254171 discusses a number of things, it doesn't cover treating the results of a long term poor diet. Actually for other medical problems, it only suggests seeing the vet. I think that is her only hope.

I am sure the solution isn't tempting her with more rich food.

You could be over concerned with how thin she is. While Shepherds and some other breeds keep themselves lean, some Poodles are almost 2 dimentional. Again, what does the vet say about her condition?