Comparison of BMI and % BF determined by bioimpedance analysis for obesity screening in young women

The body mass index (BMI) is used as the most common and simplest measure to predict obesity. The aim of the study was to compare the BMI method and % BF (body fat) determined by bioimpedance analysis for obesity screening and to evaluate the correlation between these methods. 200 women aged 18-25 years were included in the study. BMI ≥ 25/ ≥ 30 kg/m² was the criterion for assessment of overweight/obesity. Body fat (BF) in % and kg was determined by bioimpedance analysis. For assessment of obesity by % BF, the criterion was ≥ 30% fat. Based on BMI, 4.5% of women were obese, 14.5% were overweight. According to % BF, up to 30% of women were obese. The largest differences between BMI and % BF categorization were found in the underweight and overweight groups. According to the BMI 43% of women in the underweight category and 34.5% in the overweight category had a % BF in the normal range. By correlation analysis, we found a strong positive statistically significant correlation in women between BMI and BF (%) (rs = 0.782, p < 0.01) and also between BMI and BF (kg) (rs = 0.880, p < 0.01). Both of these methods assess body composition in their own specific way, complement each other, and other combining them, we achieve more accurate results for determining the overall health status of an individual.