nigtshade foods are tomatoes, potatoes, all peppers (sweet and hot, but not peppercorn, that's a different plant), eggplant, paprika, goji (wolf) berries, ground cherries, tomatillos. Modified food starch can be potatoes. Pre-cooked chicken is almost impossible to find wiithout paprika. Watch for ingredients that just say "spices" or "spice extractives". Even "natural flavorings" doesn't tell you what's in there.
They seem to be in most of the American Standard Diet.