Age-related changes in body composition in a sample of Czech women aged 18–89 years: a cross-sectional study

BACKGROUND The Czech Republic lacks body composition data for women. Therefore, the purpose of the study was to analyze body composition [body fat mass (BFM), fat-free mass (FFM), body fat percentage (%BFM) and visceral adipose tissue (VAT)] and to evaluate the changes that occur with aging in women aged 18-89 years. We also analyzed anthropometric characteristics of study participants and developed age-specific percentile curves for body composition parameters. METHODS A cross-sectional, non-randomized study was conducted with a sample of 1,970 apparently healthy Czech women. Body composition was measured using a direct segmental multi-frequency bioelectrical impedance analysis (BSM-BIA). RESULTS The mean BFM was 19.7 ± 8.9 kg, and BFM reached its peak in women over 70, at 27.6 ± 8.8 kg. There was a strong correlation between BFM and age (r = 0.61; r (2) = 0.37). Fifty percent of the women in the study had a BFM between 13.0 and 25.0 kg. The %BFM (r = 0.69; r (2) = 0.47) and VAT (r = 0.88; r (2) = 0.77) were also significantly associated with age. The reference range for %BFM was 22.0-35.6 % (25th-75th percentile). The mean FFM was 45.8 ± 5.5 kg, and FFM decreased with age (r = -0.27; r (2) = 0.07). CONCLUSIONS The results presented in this study showed a statistically significant increase in BFM, %BFM and VFA as age increased, and the values reached their peak in women over 70. Even when FFM decreased slightly with age, body weight increased because of the increase in BFM.