INS and polycystic ovary syndrome: This review systematically summarizes how natural products exert beneficial effects through mechanisms such as improving metabolic homeostasis by enhancing insulin sensitivity and mitigating oxidative stress and chronic inflammation; restoring endocrine balance by modulating the hypothalamic-pituitary-gonadal axis to reduce hyperandrogenemia and promote ovulation; and utilizing emerging pathways including regulating gut microbiota homeostasis and epigenetic modifications as a novel avenue for PCOS drug development.