Introduction

The measurement of body composition occurs in many branches of biology and medicine. It is measured by the human biologist studying human variation and adaptation and it is being used increasingly in the assessment of nutritional and growth status, fitness, work capacity, disease and its treatment. In human energetics, it is widely used for the standardisation of variables such as basal metabolic rate or physical work capacity in, for example, the investigation of the types and scope of adaptation to chronic energy and nutrient deficiency or excess.

Most determinations of body composition, whether for research or surveillance purposes, are made in the field as opposed to the laboratory or bedside. There is then a clear need for simple, rapid, safe, accurate methods to determine body composition in population studies. For many years anthropometry has, to some extent, met this need. Body composition has properties additional to those of size, i.e. weight and linear dimensions, but weight/height indices have been and continue to be used widely as proxies for body composition measurements. The best known of these is the Body mass index (BMI) or Quetelet's index.

Skinfold thicknesses stand in their own right as indices of fat and fatness and, by difference, of leanness. There are reference data for all ages and both sexes. The practice of estimating body composition from anthropometric variables is fraught with pitfalls as many of the published equations have not been proved to be of general validity.