My breath test showed >20ppm methane, but my weirdest SIBO symptom was joint pain from fructans

Back pain and joint pain were primary symptoms, learned later that I was coincidentally avoiding the foods most likely to trigger the more common constipation symptom (for me it's triggered by lactose consumption). Have had confirmed >20ppm methane breath tests from multiple labs. Worked with dietician to isolate which FODMAPs I'm sensitive to: everything except GOS, which is nice because that means I can eat some types of nuts while otherwise eating low FODMAP (which is effective for managing my symptoms). The most important thing I discovered though was that my non-intestinal pain, which was pain in my knees, feet, and hands, was specifically caused by fructan consumption.