Comparison of predicted body fat percentage from anthropometric methods and from impedance in university students

The objective of the present study was to compare different methods for evaluating body fat percentage (BF%) (anthropometric methods and bioelectrical impedance analysis) in university students. Subjects were 653 healthy students whose mean age, body height, body weight and BMI were 21.1 (SD 2.5) years, 166.0 (SD 8.4) cm, 62.8 (SD 11.0) kg and 22.7 (SD 3.1) kg/m(2), respectively. Results showed that BMI is a poor predictor of body fatness since the sensitivity was low in comparison with the reference method (Siri equation). The lowest values of BF% were obtained using the reference method (Siri equation) (21.8 (SD 6.8)%). The two methods with the highest agreement were Siri and Lean (mean difference, -0.5), followed by Brozek (mean difference, -1.4) and Deurenberg (mean difference, -1.5). The largest mean difference for BF% was between Siri and impedance (-4.5). Although the methods and/or equations used in the present study have been commonly utilised to estimate BF% in young adults, the results must be interpreted with caution in the diagnosis and monitoring of overweight and obesity.