ORIGINAL CONTRIBUTION 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 partici-pants 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 analy-sis (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; r2 = 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; r2 = 0.47) and VAT (r = 0.88; r2 = 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; r2 = 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 i