Nutritional state of Polish prepubertal children assessed by population-specific and international standards.

OBJECTIVE: To assess the frequency of obesity, overweight and underweight (thinness) in Polish 7-9-year-old children using a population specific definition as compared to the French, US and IOTF references based on body mass index (BMI).

DESIGN: Height and weight were measured and BMI was calculated in a randomly selected representative sample of 7-9-year-old Polish children (N = 2916; 1445 girls; 1471 boys) to define their nutritional status. Overweight (including obesity) was estimated according to four and underweight (thinness) according to three definitions Polish national references; French references; United States references and International Obesity Task Force references.

RESULTS: According to Polish, French, U.S. and IOTF references overweight (including obesity) was found in 12.1, 14.3, 20.7 and 15.4% of children, respectively; 3.5, 9.4 and 3.6% of children were obese according to national, U.S. and IOTF references, respectively while underweight (thinness) was present in 6.9, 2.6 and 4.2% of children according to Polish, French and U.S. references, respectively. A trend of decreasing overweight and increasing underweight through age classes was observed.

CONCLUSION: The rates of underweight (thinness), overweight and obesity in Polish 7-9-year-old children calculated according to the national, French, U.S. and IOTF references were significantly different. Therefore even if the IOTF reference is considered superior for international epidemiological studies, population specific standards should probably coexist for clinical practice.