Therapeutic effects of chromium supplementation on women with polycystic ovarian syndrome: A systematic review and meta-analysis

Background: Polycystic ovarian syndrome (PCOS) has been treated recently with chromium supplementations. However, it is unknown if this dietary supplement has similar effect to metformin. Aim: The aim of this study was to investigate the efficacy of chromium supplementation in women with PCOS. Methods: A meta-analysis was conducted using relevant articles obtained from searches of PubMed, Scopus, Embase, and Google Scholar. The mean difference and standardized mean difference were employed to determine the effect size for biochemical parameters. Results: A total of 10 randomized controlled trials involving 683 women were included in the analysis. The results indicated that chromium supplementation, as vs a placebo, significantly decreased fasting blood insulin (P = 0.01), triglyceride (P < 0.00001), total cholesterol (P < 0.00001), very low-density lipoprotein (P < 0.00001), low-density lipoprotein (P = 0.0003), high sensitivity C-reactive protein (P = 0.02), malondialdehyde (P = 0.007), follicle stimulating hormone (P = 0.0007), and prolactin (P = 0.01), and increased the Quantitative Insulin Sensitivity Check Index (P = 0.02), total antioxidant capacity (P < 0.0001), and ovulation incidence (P = 0.001). Chromium supplementation was also found to be more effective than metformin in reducing HOMA-IR (P < 0.00001), and luteinizing hormone (P = 0.04). Conclusion: Chromium picolinate supplementation at a dosage of 200 μg may provide benefits similar to metformin with regard to FBG, FBI, ovulation, and pregnancy incidence, with fewer side effects in patients with PCOS. Further experiments are still required to draw effective dietary guidelines related to chromium.