Fat-free mass and fat mass reference values by dual-energy X-ray absorptiometry (DEXA) in a 20-80 year-old Italian population

Studying body composition is important in nutritional assessments and, according to the simplest two-compartment model, involves in determining fat-free mass (FFM) and fat mass (FM). FFM is composed of all non-fat tissues and represents the main active component from the metabolic point of view.1 A main function of FM is as an energy reserve, because it consists of triglycerides, which have a high caloric power.