Body composition and basal metabolic rate: A comparative study in women with and without polycystic ovary syndrome

Abstract Background: Polycystic ovarian syndrome (PCOS) is linked to metabolic dysregulation, yet its impact on basal metabolic rate (BMR) remains unclear. This study explores BMR differences between women with and without PCOS and examines key body composition predictors. Methods: This case–control study was conducted on 200 women (100 PCOS and 100 non-PCOS) aged 18–40 years. Body composition, including fat mass, lean body mass (LBM) and fat-free mass index (FFMI), was assessed using bioelectrical impedance analysis. BMR was measured, and multiple regression analysis was performed to identify predictors of BMR. Results: Women with PCOS had significantly higher BMR (1400 ± 136.8 KCal/day) than controls (1327.5 ± 131.7 KCal/day, P < 0.001). LBM strongly predicted BMR in PCOS, while waist circumference and height were keys in non-PCOS. Body composition explained 90% of BMR variance in PCOS and 77% in controls. Conclusions: Despite higher BMR, women with PCOS showed greater adiposity, indicating metabolic inefficiencies. LBM was a key determinant, emphasising the need for body composition-focused interventions in PCOS management.