An anthropometric model for determination of total body water (TBW) consisting of specific equations previously proposed by the authors: Men TBW (1) = 9.349 + 0.617Weight (kg) - 0.931Mid arm circunference (cm) + 0.122Dynamometry (kg), and women TBW (1) = −5.531 + 0.343Weight (kg) - 0.213Triceps Skinfold (mm) + 0.148Dynamometry (kg) + 3.424Wrist diameter (cm) was validated by comparing with deuterium dilution technique TBW measurement. The study was conducted in 41 healthy subjects, 20 men and 21 women, selected to assure comparability with the previous study. The required anthropometric measurements for the model were done.Average TBW measured with anthropometric models was 29.4 (95% CI 27.6,31.2) for women and 34.5 (95% CI 32.5, 36.5) for men and TBW values measured with isotopic dilution were 29.8 (95% CI 27.9,31.7) in women and 34.8 (95% CI32.9,36.7). Bland and Altman analysis was used to compare both methods. The mean difference (1) between measurements is 0.4 (95% CI −6.46,7.26) in women and 0.3 (95% CI −6.36,+ 6.96) in men.The excellent agreement between the model based on anthropometric variables and the isotope dilution technique for body composition allows its utilization in the evaluation of nutritional status in the elderly. Furthermore, the validated model can be useful for clinical and epidemiological studies considering its low cost and easiness. Copyright © 1996 Elsevier Science Inc.