The Impact of the Menopausal Transition on Body Composition and Abdominal Fat Redistribution

Objective: To evaluate the impact of the menopausal transition on body composition across different body mass categories and to identify menopause-related changes in lean and fat tissue distribution. Methods: This retrospective cross-sectional study included 325 women whose clinical and body composition data were extracted from existing records. Participants were classified as premenopausal (controls), perimenopausal, or postmenopausal and further stratified by body mass index (BMI) into normal-weight, overweight, and obesity groups. Body composition had been assessed using bioelectrical impedance analysis. Results: Across all BMI categories, postmenopausal women demonstrated significantly lower lean body mass, soft lean mass, skeletal muscle mass, total body water, protein, and mineral content compared with premenopausal and perimenopausal women (p < 0.05). Total and visceral fat area (VFA), body fat percentage (BF), and waist-to-hip ratio were significantly higher, indicating a shift toward central adiposity. These changes were most pronounced in normal-weight women (VFA: 36.4 ± 17.0, 48.3 ± 22.3, and 55.7 ± 23.5 cm²; BF: 24.8 ± 5.3%, 27.2 ± 5.2%, and 28.8 ± 4.6% in pre-, peri-, and postmenopause, respectively), and less marked among overweight women (VFA: 91.5 ± 36.3, 106.1 ± 38.2, and 111.7 ± 28.6 cm²; BF: 36.0 ± 3.6%, 36.4 ± 3.9%, and 37.2 ± 3.2%) and with obesity (VFA: 180.3 ± 62.4, 212.6 ± 96.2, and 175.5 ± 54.4 cm²; BF: 44.5 ± 4.5%, 44.5 ± 5.7%, and 41.9 ± 3.3%), suggesting a relative attenuation of muscle loss at higher BMI. Conclusions: Postmenopausal women showed a clear shift toward lower lean mass and greater central adiposity across BMI categories. These patterns indicate a consistent deterioration in body composition during the menopausal transition. Assessment of visceral fat in postmenopausal women is crucial, as its accumulation is closely linked to cardiometabolic risk. Menopause-related hormonal changes favor central adiposity, supporting the use of visceral fat as a key indicator for early risk stratification and preventive interventions in midlife women.