Dual-energy x-ray absorptiometry (DXA) is considered to be the gold standard for assessment of the body composition (BC). BC dependence on body mass index (BMI) increase was assessed with DXA in 88 women, divided in 4 groups according to their BMI (kg/m2): gr.1<25; gr.2 (25-29.9); gr.3 (30-34.9) and gr.4 (35-40). Fat mass (FM) and FM% were determined as well as lean body mass (LBM), fat free mass (FFM) and bone mineral content (BMC). Body weight (BW) values in gr.1 (58.73±5.78kg), gr. 2 (69.14±5.58kg), gr.3 (80.58±6.16kg) and gr.4 (90.67±8.53kg), were significantly different between the groups and correlated with BMI (p<0.0001). FM progressively and significantly increased from the 1stgr. (19.79±4.89kg), to the 2nd gr. (28.7±3.87kg), 3rdgr (36.49±4.71kg) and 4thgr. (43.91±6.36kg). Android FM (AFM) increased progressively, and percentage of its increase was higher compared to gynoid FM (GFM) increase in all groups. LBM in the 1stgr was (35.71±3.79kg) and 2ndgr. (37.01±2.84kg), but in the 3rdgr. (40.51±3.98kg) and 4thgr. (43.27±3.09kg) were significantly higher. LBM/FM ratio was significantly higher in the 1stgr. compared to the other groups in which it progressively lowered, showing higher FM compared to LBM increase in obese women. BMI correlated significantly with BW, FM and FM%. BMC was not significantly different among the groups. BMI increase in obese women was characterized with no significant increase of BMC, lower LBM increase compared to FM increase, significant BW and FM increase in all compartments, significant trunk FM increase as a result of dominant AFM increase, and lower legFM increase. DXA provided accurate and precise BC assessment.
