Subgroup analyses revealed that the beneficial effect of dietary fiber on reducing serum IL-6 was consistent across all subgroups, including study design, race, CKD status, study risk of bias, type, dosage, solubility, and duration of fiber supplementation (p for interaction = 0.96, 0.78, 0.42, 0.84, 0.75, 0.84, 0.75, 0.34, respectively; Table S2). The gene discussed is IL6; the disease is chronic kidney disease.