Body mass index (BMI) is a reliable index to estimate obesity as a risk factor for deteriorating health

The objective of this study was to find out what index is appropriate to evaluate obesity, by measuring body fat using bioelectrical impedance analysis (BIA). Subjects in this study were 74 women, aged 44 to 73, living in Tokushima prefecture. The means +/- standard deviation (SD) of Broca index, Body mass index (BMI) and body fat were 103 +/- 14.3%, 23.0 +/- 2.8 kg/m2 and 28.1 +/- 5.5%, respectively. In addition, their clinical data such as blood pressure, glutamate-pyruvate transaminase activity (GPT), triglycerides (TG) and fasting blood sugar (FBS) were within normal ranges. When compared with correlation between obesity indices (Broca index or BMI) and height, there was a negative correlation between Broca index and height (= -0.447). Furthermore, the number of obese subjects estimated by Broca index was less than that of obese subjects estimated by BMI. Although both Broca index and BMI showed higher correlations with body fat estimated by BIA, BMI (r = 0.927) showed a higher correlation compared to that of Broca index (r = 0.875). These results suggest that BMI is a reliable index to evaluate the body fat.