Applied nutritional investigationA 360-degree overview of body composition in healthy people: Relationships among anthropometry, ultrasonography, and dual-energy x-ray absorptiometry

ObjectiveThe aim of this study was to test the relationship between anthropometry, ultrasonography, and dual-energy x-ray absorptiometry (DXA) for the assessment of body composition in clinical practice.MethodsThe study was carried out in Italian blood donor volunteers belonging to five different age groups (18-70 y old; 25 men and 25 women per group; N = 250 participants; n = 125 men, n = 125 women). A complete history was collected and routine blood analyses were performed to confirm healthy status. All participants were submitted to whole-body DXA (tricompartmental analysis, regional, and total body), ultrasonography (abdominal adiposity evaluation), and anthropometric measurements. DXA was used as gold standard and its biomarkers were taken as reference for fat-lean mass balance, central-peripheral fat distribution, central or visceral fat, and subcutaneous fat.ResultsAnthropometric and ultrasound parameters were closely associated with most of DXA parameters. Composite markers representative of central and abdominal visceral fat compartments were significantly correlated with waist circumference, waist-to-hip ratio, and intra-abdominal fat thickness by ultrasound, in both men and women (P < 0.025). As expected, subcutaneous depots were significantly correlated with maximum subcutaneous fat thickness measured by ultrasonography (P < 0.025).ConclusionsBoth anthropometry and ultrasonography provide a reliable estimate of visceral adipose tissue in a non-obese population compared with DXA, whereas anthropometry prediction of subcutaneous adiposity is weak. Physicians should be aware of the limits of these techniques for the assessment of body composition.