Yes, apparently plants in the nightshade family which include potatoes (not sweet potatoes), tomatoes, peppers (not black pepper but all others) and eggplants can trigger arthritis. I honestly don't know if this has been scientifically proven but there seems to be a lot of information out there and some people who suffer from arthritis say it's true so I figured I see if removing these things from the diet would do anything at all
With respect to Darford, I haven't heard a lot about it. Posted another thread in the dog food section and a few replied. Most seemed to think it was a good quality food. The price is certainly indicative of that. Did you hear that it wasn't so great?