INS and polycystic ovary syndrome: He et al. assessed the efficacy of antioxidant supplementation in PCOS, and this meta-analysis revealed that the fasting blood glucose levels [standardized mean difference (SMD): −0.31, 95% confidence interval (CI): −0.39 to −0.22, p < 0.00001], the homeostatic model assessment of insulin resistance (SMD: −0.68, 95% CI: −0.87 to −0.50], p < 0.00001), and insulin levels (SMD: −0.68, 95% CI: −0.79 to −0.58, p < 0.00001) were significantly lower in patients with PCOS taking antioxidants than those in the placebo group [54].