An improved calibration for the in vivo determination of body nitrogen, hydrogen, and fat
- 1 March 1984
- journal article
- research article
- Published by IOP Publishing in Physics in Medicine & Biology
- Vol. 29 (3), 209-218
- https://doi.org/10.1088/0031-9155/29/3/001
Abstract
Additional investigation of an original technique for measuring total body N by prompt .gamma. neutron activation demonstrated the need for certain changes in the calibration procedures to apply the method to studies of patients with abnormal metabolism. Total body N, hydrogen and fat were derived, simultaneously, from data obtained by neutron capture .gamma.-ray analysis combined with the measurements of body weight, total body weight and total body Ca. In this improved calibration technique, total body N is more accurately measured, not only in normal subjects, but also in obese subjects and in patients with marked changes in hydration, such as cancer patients. The fat values calculated do not rely on a fixed relationship of total body water or total body K when lean body mass as in the previous studies, but are calculated as the difference between body weight and the sum of body water, protein and bone mineral ash. This improved technique was applied to the study of 3 groups of subjects: the general population with a normal weight distribution, and 2 extremes represented by obese and cancer patients.This publication has 13 references indexed in Scilit:
- Effects of caloric restriction on body composition and total body nitrogen as measured by neutron activationMetabolism, 1983
- Changes in body composition of cancer patients following combined nutritional supportNutrition and Cancer, 1982
- Comparison of methods of estimating body fat in normal subjects and cancer patientsThe American Journal of Clinical Nutrition, 1981
- Body composition and dietary intake in neoplastic diseaseThe American Journal of Clinical Nutrition, 1981
- Compartmental body composition of cancer patients by measurement of total body nitrogen, potassium, and waterMetabolism, 1981
- The use of body hydrogen as an internal standard in the measurement of nitrogen in vivo by prompt neutron capture gamma-ray analysisJournal of Radioanalytical and Nuclear Chemistry, 1979
- Fractional charge collection technique for pile-up reduction - counting low intensity radiation in presence of intense gamma-ray and neutron backgroundNuclear Instruments and Methods, 1977
- OBITUARYHealth Physics, 1976
- Changes in body chemical composition with age measured by total-body neutron activationMetabolism, 1976
- Body fat assessed from total body density and its estimation from skinfold thickness: measurements on 481 men and women aged from 16 to 72 YearsBritish Journal of Nutrition, 1974