COMPARISON OF THE BODY MASS INDEX TO OTHER METHODS OF BODY FAT ASSESSMENT IN BULGARIAN CHILDREN AND ADOLESCENT

摘要

The purpose of this study is to assess the body composition and body nutritional status of children and adolescents with the values of BMI and the percentage of body fat. We transversally examined 2269 children and adolescents from South Bulgaria /1114 boys and 1155 girls/, aged 7 to 17 during 2008-2009. We applied the anthropometric and bioimpedance-metric methods. The results show that throughout the observed age period, boys have a bigger amount of fat-free body mass per unit height, and girls accumulate greater amount of fat mass per unit height. According to the BMI data, the average frequency of occurrence of underweight is 5% higher in girls, while the frequency of occurrence of overweight is on average 9% higher in boys. The comparison of the results for body nutritional status from both methodical approaches shows that according to the percentage of body fat, the average frequency of underweight occurrence is higher than the average frequency of overweight and obesity occurrences, but according to the discriminatory BMI values, the frequency of overweight occurrence is much higher. This is probably due to the fact that the discriminatory values of BMI were developed for each age and gender groups, while those for the percentage of body fat, although developed for both sexes, were the same for the entire age period. The results obtained confirm the need the body nutritional status of children and adolescents to be assessed through at least the two components of the body weight.