I was recently diagnosed with Fibromyalgia. About 12 years ago I developed a sever intolerance to dairy. Since I was diagnosed as allergic to all kinds of pollen as a ki, I assumed that I was allergic to dairy. Several allergists over several years could not show that I had a true allergy to dairy. Along with dairy, I also cannot tolerate sodium lactylate or any lactylate said unless they are plant derived. Lactylates are in gravies, soups, breads, lunch meat, ham, etc. pretty much all processed foods. Jump forward 10 years and I'm also intolerant to gluten. I went to gastroenterologist and I am not Celiac, just intolerant. Diagnosed with IBS. Jump forward another year and start having widespread pain, anxiety, IBS went out of control, depression set in. Finally got an appointment with a rheumatologist, my angel, who diagnosed Fibromyalgia. Many people with Fibromyalgia also have IBS. I guess it is the same weird brain/nerve disorders.
IBS sufferers follow an elimination diet to discover what foods bother them, or follow the FODMAP diet which works for many. Basically, eat Paleo and you will be able to manage it better.