Understanding normal changes in the body's composition with old age and their health and nutritional implications is important in determining the nutritional status of the elderly. Suitable reference data for anthropometry and body composition obtained from large representative samples of black, white, Hispanic, and Asian elderly persons are needed to improve their nutritional health and care. Distribution statistics for body measurements of persons 65 to 80 years of age are available from national health and nutrition surveys, but for persons older than 80 years, there is little information. Recumbent anthropometric techniques have been developed that are applicable. Underwater weighing continues to be a gold standard for determining body composition in the elderly, but a four-compartment model would improve estimates of body composition in the elderly because of changes in the density of the fat-free mass with old age. Noninvasive methods such as anthropometry and bioelectric impedance could be used to predict body composition if they were validated against direct methods and if appropriate equations become available.