VALIDATION OF EXPEDIENT METHODS FOR MEASURING BODY-COMPOSITION IN INDIAN ADULTS

The body composition of 99 men and 89 women from south India was estim ated using hydrodensitometry, bioelectrical impedance and skinfold thi ckness. Comparisons of the hydrodensitometry (reference method) and sk infold methods showed that there were no significant differences betwe en the methods, for estimates of fat free mass (FFM) and per cent fat. The mean difference between the estimates FFM (bias), from skinfold m easurement and hydrodensitometry was small for both groups (+0.16 +/- 1.09 kg in men and +0.67 +/- 0.90 kg in women). The same trend was obs erved in per cent fat estimates (-0.37 +/- 2.04 in men and -1.49 +/- 2 .28 in women), showing that the skinfold method can be used as an accu rate and expedient method to determine body composition. The bioelectr ical impedance method obtained a significantly lower FFM and higher bo dy fat than the reference (hydrodensitometry) method. This could have been due to the use of an inappropriate equation derived from Western population studies. Hence, a new predictive equation, for the measurem ent of FFM by the bioelectrical impedance method was derived for this population, using the variables of height(2)/impedance and FFM measure d by underwater weighing. The new equation for the bioelectrical imped ance method then gave values of body composition which compared well ( 0.26 +/- 2.32 kg) in men and (0.36 +/- 2.49 kg) in women with the hydr odensitometry method.