Bioelectrical impedance analysis and hormonal assessment in adolescents with pubertal gynecomastia

Objectives Gynecomastia is common during adolescence, yet its relationship with body composition remains unclear. This study investigates differences in body composition, fat distribution, and hormonal profiles between adolescents with gynecomastia and healthy controls. Methods This case–control study included 70 adolescents diagnosed with gynecomastia and 67 healthy controls matched for age and Tanner stage. Anthropometric measurements, bioelectrical impedance analysis (BIA), and serum hormonal profiles were assessed. Body composition parameters, including fat mass (FM), fat-free mass (FFM), muscle mass (MM), bone mass (BM), total body water (TBW), muscle-to-fat mass ratio (MFR), and basal metabolic rate (BMR), were measured using the Tanita MC-780 MA device. Results Adolescents with gynecomastia exhibited significantly higher trunk fat mass (trunk fat mass: 20.60 ± 9.48 % vs. 17.64 ± 6.61 %, p=0.0462) and hormonal alterations, including reduced follicle-stimulating hormone (FSH) and free thyroxine (fT4) levels (FSH: 2.7 ± 1.4 vs. 3.5 ± 2.0 IU/L, p=0.0164; fT4 12.4 ± 1.9 vs. 13.1 ± 2.5 p=0.0193). Conclusions These findings highlight the interplay between adiposity and endocrine changes in gynecomastia, warranting further exploration of underlying causative factors.