Physique and body composition: comparisons of methods and results

Body mass is the most investigated measurement for the evaluation of the nutritional and health status of children and adults. To apply it requires consideration of its correlations with sex, height and age, and if possible the type of body shape. It requires also the consideration of body composition, in particular the total body fat content. Here a problem arises. While classic anthropometric techniques are suitable for field investigations with large samples, the investigation of body composition needs the highly technical equipment of a laboratory as a rule. Based on a representative sample of 21,648 males and 21,391 females from all the new federal states of Germany this paper tries to find easily obtained anthropometric measurements which are usable for a type specific estimation of body composition under field conditions. For this reason body mass by sex and height is classified by three different concepts: the skeletal concept with categories of frame size, estimated by the frame index, the whole body concept with categories of corpulence, estimated by the metric index, and the fat concept with categories of subcutaneous fat layer thicknesses. Focussing on a type-specific body mass by height for an assessment of the nutritional status, the skeletal concept is proved to be the best. The summary of body mass and height by the body mass index (BMI), measured in kg/m2, gives the possibility of bringing two measurements into one dimension and to leave the second dimension free for the important variable of age. BMI by sex, age and frame type is found to be a good and practical instrument for the assessment of the nutritional and health status.