MEASUREMENT OF NUTRITIONAL-STATUS USING CONVENTIONAL ANTHROPOMETRY AND D2O IN SARAWAK, MALAYSIA

Objective: To evaluate the effect of different methods (plateau or bac k extrapolation) of calculating total body water (TBW) from deuterium dilution in an environment characterised by high water turnover. The b ack extrapolation model is assumed to be more accurate when water turn over is high. Design: Cross-sectional study with measurement of body c omposition by deuterium dilution and conventional anthropometry. Setti ng: Rural Sarawak, Malaysia. Subjects: 24 adults of the Iban populatio n. Results: TBW was significantly different by method of calculation ( P < 0.0001), and mean fat free mass was lower by 1.3 kg using the back extrapolation technique, equivalent to a mean 3.1 (s.d. 0.8)% reducti on. The same 1.3 kg difference was equivalent to a mean 16.6 (s.d. 12. 3)% increase in fat mass using the back extrapolation technique. Back extrapolation values were used in subsequent analyses. Percentage fat correlated significantly with BMI and skinfold thicknesses in females, but only with BMI in males. Fat mass was significantly correlated wit h skinfolds and BMI in both sexes. Fat free mass was correlated with B MI in both sexes. Conclusions: The back extrapolation method produced values for fat mass that differed substantially from those obtained by the plateau method. The difference between calculation methods could be lessened by using saliva samples in place of urine. Back extrapolat ion values for body fat correlated well with anthropometric measuremen ts in females, less well in males. This difference is due to character istics of the study population.