Comparison of Effectiveness of Body Mass Index and Bioelectrical Impedance Methods in Assessment of Obesity

Objective: Obesity is a common public health problem in both developed and developing countries nowadays. Due to health risks associated with obesity, easy, precise, reliable, cost-effective, and broadly applicable methods are necessary for its assessment in population based studies and in clinical practice. The purpose of this study was to determine the prevalence of obesity in university students according to the international standards of body mass index and body fat percentage obtained by bioelectrical impedance and to compare these two different methods for defining obesity. Material and Methods: A cross-sectional study was carried out among 400 undergraduate students from Ankara University, Ankara, the capital of Turkey. Body height was measured with a portable stadiometer (Holtain Ltd. Harpenden). Body weight, body fat mass, body fat percent, fat free mass and total body water were obtained using BIA method by Tanita BC-418 MA (Tanita Corporation of America, Inc., Arlington Heights, IL). Results: Mean body fat percent assessed by bioelectrical impedance was 25.3 ± 7.2% in women and 15.99 ± 5.6% in men. This study demonstrated a lower prevalence of overweight and obesity in university students compared with Turkish general population. Our observation has also established that there is significant correlation between body fat and body mass index in both sexes (p=0.000). Furthermore, this correlation was greater in women compared with men. Conclusion: Our results show that bioelectrical impedance is more useful than body mass index in assessment of obesity in population based studies.