In my late twenties, I developed terrible asthma. I ended up in the hospital and almost died. This continued apace, really knocking me down. Bear with me, it does relate. A man taking a course I was teaching named Peter Pfeiffer told me that I seemed like a person with a dairy allergy. He suggested that I go ten days without dairy and see if I felt better. I did--it was like a miracle. I was a new person.
I looked at my diet and discovered I was having cheese omelets for breakfast, toasted cheese sandwiches for lunch, macaroni and cheese for dinner (etc). I literally did not know what to eat. Dairy was in everything I ate.
I started substituting soy milk for milk, tofu and soy cheese for cheese and I developed fibromyalgia. Slowly. I didn't connect it with the soy. But eventually, it got so bad I literally couldn't walk to the end of my driveway I was in so much pain. I did a rotation diet and discovered it was the tofu and soy. When I eliminated that, I felt better, BUT then I developed a sensitivity to beans, peas etc, especially the dried ones.
Meanwhile, my allergist suggested reintroducing dairy, since I hadn't had it in many years--she thought I may have outgrown the allergy. Wrong--I immediately developed asthma AND fibromyalgia (or fibromyalgia-like symptoms.)
What this means is that I have to prepare all my own meals from scratch because everything (all prepared foods) has either dairy or soy or both. And it was the protein in dairy and the protein in soy that created the problem.
After experiencing fibromylagia so bad I literally couldn't walk, it now is more of an inconvenience most of the time. I totally avoid sugar and refined grains (Which turn into sugar), nuts of all kinds, dairy, soy, caffeine (I have no soda, coffee, tea, chocolate etc). I exercise (walk, run, bike) 45 minutes a day and go to bed around 10-10:30 (good sleep is essential). I drink only water and eat only fresh whole foods, organic if possible. I do eat nightshades, in limited quantities.
I do eat wheat (whole grain only) and have been considering testing that as well, since I still have some residual pain that flares up toward the end of a long walk.