All people with fibromyalgia and chronic fatigue are different, and there is no one diet that works for everyone. However, many people with FM, CFS and other autoimmune conditions report great improvements in pain and fatigue levels when they remove gluten from their diet. Other foods that often cause problems are sugar, artificial sweeteners and nightshade vegetables (tomatoes, potatoes, eggplant and peppers). Most people also do well when eating less processed foods and a diet rich in fruits, vegetables and whole grains.