Inulin Fiber Improves PCOS by Reshaping Gut Bacteria and Reducing Inflammation

Polycystic ovary syndrome (PCOS) affects up to 20% of reproductive-age women, causing irregular periods, hyperandrogenism, and metabolic dysfunction. This comprehensive study reveals how inulin, an affordable prebiotic fiber, can significantly improve PCOS through gut microbiome modulation.

Researchers conducted both human clinical trials and mouse experiments using PCOS models induced by dehydroepiandrosterone and high-fat diet. In the clinical cohort, PCOS patients received inulin supplementation, while mouse studies tested various dosages and included fecal microbiota transplantation experiments to prove causation.

Inulin treatment produced remarkable improvements across multiple PCOS parameters. In mice, it enhanced glucose tolerance, reduced insulin resistance, normalized testosterone levels, restored regular estrous cycles, and improved ovarian morphology. The treatment specifically increased microbial co-abundance group 12, including beneficial Bifidobacterium species and other short-chain fatty acid (SCFA) producers. Fecal SCFA levels increased significantly, while inflammatory markers like lipopolysaccharide-binding protein decreased.

Crucially, fecal microbiota transplantation from inulin-treated patients into antibiotic-treated mice reproduced the beneficial effects, definitively proving the gut microbiome mediates inulin's therapeutic action. When researchers administered lipopolysaccharide to counteract the anti-inflammatory effects, inulin's benefits were reversed, confirming inflammation reduction as a key mechanism.

These findings suggest that targeting gut microbiota represents a promising, accessible therapeutic strategy for PCOS management, potentially offering an alternative to current limited treatment options.