Introduction: the use of body mass index to assess obesity in children

The International Obesity Task Force (IOTF) was established in 1994 to address the increase in the worldwide prevalence of obesity. The goals of the IOTF are to 1) raise awareness in the population and among governments that obesity is a serious medical condition, 2) develop policy recommendations for a coherent and effective global approach to the management and prevention of obesity, and 3) implement appropriate strategies to manage and prevent obesity on a population basis worldwide. To assess the global prevalence of obesity in children and adolescents, the IOTF convened a workshop on childhood obesity to determine the most appropriate measurement to assess obesity in populations of and adolescents around the world. At the workshop, a variety of issues related to this problem were considered--including the best measure of fatness, the effect of application of a variety of existing standards on the prevalence of obesity in the same population, and the role of factors such as visceral adiposity and natural history in the definition of obesity. This article and those that follow represent the information presented at the workshop. The workshop concluded that the body mass index (BMI; in kg/m2) offered a reasonable measure with which to assess fatness in children and adolescents and that the standards used to identify overweight and obesity in children and adolescents should agree with the standards used to identify grade 1 and grade 2 overweight (BMI of 25 and 30, respectively) in adults.