American Journal of Clinical Nutrition, Vol 40, 255-259, Copyright © 1984 by The American Society for Clinical Nutrition, Inc

ORIGINAL RESEARCH COMMUNICATIONS

Improved models for determination of body fat by in vivo neutron activation

SH Cohn, AN Vaswani, S Yasumura, K Yuen and KJ Ellis

In the present study, two different models of body composition, based on data obtained by nuclear techniques are used. Total body nitrogen, calcium, and chlorine were obtained by total body neutron activation. Total body chlorine was used to estimate extracellular water, and total body calcium to determine bone mineral and extracellular solids. Total body potassium was measured by whole body counting to obtain the body cell mass. In addition, total body water was measured by the tritium dilution technique. It was found that either model can be used equally well to measure total body fat in normal subjects. Estimation of body fat as the difference between body weight and the sum of total body nitrogen (protein), total body water, and bone ash (model 1) appears to have an advantage over model 2, which uses body cell mass, extracellular water, and extracellular solids, particularly for patients with metabolic disorders. This advantage is partly due to the fact that the parameter protein (total body nitrogen) is less affected in metabolic disorders than the more labile total body potassium. The closely correlated results obtained with the two models based on nuclear measurements support the conclusion that these techniques provide reliable measurements of total body fat.

This article has been cited by other articles:

				Z. Wang, F X. Pi-Sunyer, D. P Kotler, L. Wielopolski, R. T Withers, R. N Pierson Jr, and S. B Heymsfield Multicomponent methods: evaluation of new and traditional soft tissue mineral models by in vivo neutron activation analysis Am. J. Clinical Nutrition, November 1, 2002; 76(5): 968 - 974. [Abstract] [Full Text] [PDF]

				K. J. Ellis Human Body Composition: In Vivo Methods Physiol Rev, April 1, 2000; 80(2): 649 - 680. [Abstract] [Full Text] [PDF]

				Z. Wang, P. Deurenberg, W. Wang, A. Pietrobelli, R. N. Baumgartner, and S. B. Heymsfield Hydration of fat-free body mass: new physiological modeling approach Am J Physiol Endocrinol Metab, June 1, 1999; 276(6): E995 - E1003. [Abstract] [Full Text] [PDF]

				R. A Richardson, H I. Davidson, A. Hinds, S. Cowan, P. Rae, and O J. Garden Influence of the metabolic sequelae of liver cirrhosis on nutritional intake Am. J. Clinical Nutrition, February 1, 1999; 69(2): 331 - 337. [Abstract] [Full Text] [PDF]

				R. Comizio, A. Pietrobelli, Y. X. Tan, Z. Wang, R. T. Withers, S. B. Heymsfield, and C. N. Boozer Total body lipid and triglyceride response to energy deficit: relevance to body composition models Am J Physiol Endocrinol Metab, May 1, 1998; 274(5): E860 - E866. [Abstract] [Full Text] [PDF]