Weight status among Iranian adolescents: Comparison of four different criteria

Obesity or being overweight is a major health problem in Iran. Only few studies are available that compare the obesity prevalence by four different available criteria. The aim of this study was to determine the prevalence of overweight and obesity among Isfahani adolescents based on four different definitions. This cross-sectional study was conducted on 3002 Isfahani students (1377 males; 1625 females) aged 11-18 years. Anthropometric measurements including weight and height were measured and body mass index (BMI) was calculated. Sex-specific BMI-for-age reference data of the Iranian national data, Center for Disease Control data (CDC2000), International Obesity taskforce data (IOTF), and recent World Health Organization (WHO) data was used to define overweight and obesity. The mean age of the studied population was 14.8 years and the mean BMI was 20.3 kg/m2. Girls were on an average 1.4 years older and had almost one unit higher BMI than boys. Underweight was prevalent among almost 38.5% and 25.5% of adolescents as per WHO2007 and national Iranian cut-off points, respectively. The prevalence rates reached 39.5% and 45.8% by IOTF and CDC2000 criteria, respectively. The highest prevalence of overweight was obtained by IOTF cut-points (30.5%), while CDC2000 criteria, WHO2007, and national Iranian cut-points gave similar prevalence results (4.7%, 4.0%, and 4.4%); 2.4% of the studied population were found to be obese by WHO2007 definition, while this rate was 0.8%, 0.5%, and 0.8% by IOTF, CDC2000, and national Iranian cut-points. Almost all definitions revealed coexistence of underweight, overweight, and obesity among Isfahani adolescents. Huge differences exist between different criteria for assessing weight status among children. To understand the best appropriate criteria for Iranian adolescents, future studies should focus on the predictability of obesity related co-morbidities by these criteria.