The effectiveness of nutritional supplements in improving polycystic ovary syndrome in women: a systematic review and network meta-analysis.

Background: Nutritional supplements are known to ameliorate polycystic ovary syndrome (PCOS) and have been shown to modulate endocrine and metabolic markers, oxidative stress markers and inflammatory biomarkers in patients with PCOS. A variety of nutritional supplements have been applied in clinics, but a more comprehensive ranking of their efficacy has not yet been investigated.

Objectives: To assess the comparative effectiveness of nutritional supplements in women with PCOS.

Methods: A systematic search was conducted across PubMed, EMBASE, Web of Science, and the Cochrane Library for randomized controlled trials (RCTs) that met the inclusion criteria up to October 12, 2023. We performed a network meta-analysis (NMA) to evaluate the effectiveness of various nutritional supplements on different indicators of PCOS by synthesizing both direct and indirect evidence from the trials.

Results: Seventy-nine RCTs involving 5,501 participants were enrolled in the NMA. It suggested that chromium was notably effective in improving follicle-stimulating hormone levels, total antioxidant capacity, and very low-density lipoprotein levels. Soy isoflavones were more beneficial for enhancing glutathione levels and reducing malondialdehyde levels. Inositol significantly decreased total cholesterol and triglyceride levels, while curcumin was most effective in improving low-density and high-density lipoprotein cholesterol levels. Additionally, Omega-3 was superior in reducing homeostatic model assessment of insulin resistance levels. No significant differences were observed in total testosterone, sex hormone-binding globulin, dehydroepiandrosterone, high-sensitivity C-reactive protein, and plasma nitric oxide levels between the supplements and placebo.

Conclusions: Chromium, inositol, and Omega-3 were found to be beneficial for improving lipid profile. For improving obesity, sex hormone levels, inflammatory factors and oxidative stress indicators of PCOS patients, carnitine, chromium, and soy isoflavones are effective options, respectively. These findings confirm that nutritional supplements can effectively alleviate PCOS symptoms, potentially providing valuable guidance for the clinical selection of appropriate nutritional interventions.

Trial registration: PROSPERO registration number CRD42023483534.