Essay from 2011 in the field of Nutritional Science / Dietetics, Language: German, Abstract: Bioelectrical impedance analysis (BIA) is used in the fields of nutritional science, nutritional medicine, sports medicine, human biology, and increasingly in fitness and lifestyle areas, for example, for weight reduction or to assess muscle gain in athletes. With BIA, the doctor, nutritionist, or fitness trainer determines the composition of the body and thus obtains information about a person's nutritional status. Physical and mental performance, metabolic activities, and immune defense are dependent on a person's nutritional status, which includes the food consumed and the nutrients contained within it. Additionally, non-nutritional factors such as diseases or medications also have an influence.