Numerous studies have revealed that certain nightshades can contribute to problems with arthritis, including tomatoes, peppers, potatoes, and eggplant. Those who currently have problems with arthritis will want to avoid eating tomatoes as much as possible, along with other foods that come from the nightshade family. It would also be a good idea to avoid eating certain whole foods along with prepared foods which contain chili or paprika.
There are some salad dressings which are commercially prepared and they have been known to cause problems for people who suffer from arthritis. If you currently have this problem, the best thing you can do is to avoid the above-mentioned foods as much as possible.