In the literature there is not available a uniformly accepted method for assessing the degree of obesity.
Aim: To determine how far insulin resistance, serum levels of leptin and resistin are altered in persons categorized on the basis of body-mass index (BMI), body fat percentage, and abdominal circumference.
Methods: 101 volunteer boys and 115 girls participated in the studies. Body height was measured, body mass, abdominal circumference, and body composition were determined by InBody3 bioimpedance instrument. Body mass index and body fat percentage were calculated by the instrument. Concentrations of serum glucose, insulin, leptin, and resistin were determined. Insulin resistance was calculated using the homeostasis model: HOMA IR .
Results: Body fat percentage, serum levels of leptin and resistin were significantly higher in girls than in boys. Increases in BMI, body fat percentage, and abdominal circumference were associated with the significant elevation of both HOMA IR and serum leptin concentrations. In overweight boys categorized by body fat percentage as obese the serum leptin concentrations were significantly higher than in their non-obese counterparts.
Conclusion: Determination of body composition would be important concerning the follow-up of biochemical changes occurring in the body during the course of both epidemiological studies and nutritional interventions.