Body Mass Index or body fat! Which is a better obesity scale for Pakistani population?

Objective: To compare two methods of classifying obesity based on body mass index and body fat percentage. Methods: The cross-sectional study was conducted from November 2012 to August 2013 at Jinnah Postgraduate Medical Centre, Karachi. Male and female volunteers between the ages 15-65 years were selected using simple random sampling. They were classified into different groups for body mass index and body fat percentage measured through bioelectrical impedance scale. The subjects were sub-grouped into underweight, normal weight, overweight and obese. SPSS 11 was used for statistical analysis. Results: The mean age of the 828 healthy volunteers was 25.67±10.10 years. A total of 552(66.6%) subjects had a higher body fat percentage and were misclassified by body mass index. Only 276(33.3%) subjects had body fat percentage values corresponding to the body mass index classification. The difference in terms of categorising obesity was highly significant (p 0.001).Both body mass index and body fat percentage showed positive correlation with age (r=0.144; p=0.001) (r=0.261; p=0.001) and weight (r=0.578; p=0.001) (r=0.444; p=0.001) respectively. Moreover body fat percentage showed a significant positive association with gender (r=0.109; p=0.027) whereas BMI did not. Conclusions: Body fat percentage should be incorporated for a better understanding as well as categorising of obesity.