The aim of this study is to estimate the prevalence of overweight and obesity in a current, nationally representative, random sample of pre-school-aged children in Poland and to compare their overweight and obesity rates with their peers from the US and Norway.
Material and methods: The height and weight were measured in a total of 5026 randomly sampled children aged 2-6 years and their Body Mass Index was calculated. The prevalence of overweight including obesity was determined using three definitions, i.e. those formulated by the International Obesity Task Force (IOTF), the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC).
Results: The overall prevalence of overweight including obesity in boys was 12.2%, 12.2%, 17.2% and in girls 15.0%, 10.0%, 19.1% according to the IOTF, WHO, CDC definition, respectively, and did not significantly differ in comparison with their US and Norwegian peers. The overall prevalence of obesity in boys was: 4.4%, 4.9%, 8.9% and in girls: 3.8%, 3.4%, 7.6%, according to the IOTF, WHO, CDC definition, respectively. Among Polish girls the obesity rate was higher compared to the female US peers. The obesity rate was higher in Polish boys compared to their Norwegian peers.
Conclusion: The estimates of the prevalence of overweight and obesity varied substantially by age group, gender and depending on the definition used. Obesity rates among Polish girls and boys were higher compared to their American and Norwegian peers. The influence of overweight definitions should be taken into account when studying childhood overweight and obesity. Overweight and obesity preventive programs should be implemented at preschool age.
Keywords: childhood; obesity; overweight; prevalence.