The impact of dietary interventions on polycystic ovary syndrome patients with a BMI ≥25 kg/m2: A systematic review and meta-analysis of randomized controlled trials.

Background: Dietary interventions, recommended as a primary approach globally, benefit women with polycystic ovary syndrome (PCOS) by inducing weight loss and improving clinical symptoms, metabolism, and pregnancy results. However, the impact of diet on PCOS in individuals with BMI ≥ 25 kg/m² is unclear. The aim of this review was to offer dietary guidance for these patients.

Methods: Six databases, CNKI, Wanfang, VIP, PubMed, Cochrane Library, and Web of Science, were searched systematically from inception to December 2023 for clinical randomized controlled trials (RCT) on dietary interventions for PCOS. Two researchers independently screened and extracted data following pre-defined inclusion criteria, with bias assessment using the Cochrane Handbook and Review Manager (version 5.4) software.

Results: Nine RCTs with 559 participants were included. Among women with PCOS and obesity, compared to the control group, individuals who underwent dietary interventions experienced improvements in weight-related Indicators, glycolipid metabolism, hormone-related indicators, and fertility-related outcomes. Subgroup analysis indicated that calorie-restricted diets (CRDs) and low-energy-low-carb combined diets had advantages over other dietary interventions. Moreover, the overweight period was the optimal intervention period.

Conclusions: Dietary interventions can improve the clinical manifestations of PCOS and pregnancy rates in patients with a BMI ≥ 25 kg/m². Particularly, CRDs, low-calorie-low-carb combined diets, and low-calorie-extract combined diets are recommended.