Fat Mass Is Associated with Aging Rather than Menopausal Transition

Background/Objectives: Midlife is associated with changes in body weight and fat distribution in women; however, it remains unclear whether these changes can be attributed to chronological aging, menopause, or associated lifestyle changes. The objective of this study was to compare the possible differences in body fat distribution parameters measured by regional Lunar osteodensitometry scans (DXA) between clinically healthy, BMI-matched pre- and postmenopausal women. Methods: A cross-sectional analysis of body composition parameters, such as total body, android, and gynoid fat percentage, was performed using DXA hip and lumbar scans in 171 women aged 45–55 years. Comparisons were made across 50 premenopausal (median age 47.9 (4.5) years) and 121 postmenopausal women (median age 51.7 (3.7) years), matched for median BMI (25.8 (6.7) vs. 25.6 (7.8) kg/m2). Associations between body fat outcomes and predictors were examined using multivariable linear regression. Results: No significant differences were observed between study groups in body composition parameters, including android fat percentage (%), gynoid fat%, total body fat%, or android/gynoid ratio. Unlike age, menopausal status, or years since menopause, BMI was the only significant predictor of body fat distribution. In the entire cohort, total body fat percentage showed a modest but significant positive correlation with age (ρ = 0.200, 95%CI [0.043, 0.345], p = 0.009), while the menopause onset age was positively correlated with BMI (ρ = 0.195, 95%CI [0.002, 0.369], p = 0.032). Among postmenopausal women within the first two years of menopause, the android/gynoid ratio showed a positive correlation with years of estrogen deprivation (ρ = 0.451, 95%CI [0.144, 0.707], p = 0.007). Conclusions: Age was correlated with higher total body fat %; neither age nor menopausal status was correlated with BMI. In early postmenopause, the android/gynoid ratio increased with years since menopause. The median age at menopause observed in our study was 48 years, which is lower than in other Caucasian studies.