Body Mass Index and Waist Circumference Rather Than Body Adiposity Index Are Better Surrogates for Body Adiposity in a Chinese Population

Background: Several studies have found that body adiposity index (BAI) is a better index of body adiposity than body mass index (BMI) in African and Mexican American adults. This study aims to evaluate the ability of BAI to predict body adiposity in Chinese children and adults. Materials and Methods: In total, 2425 children and 5726 adults were recruited from rural China. All participants completed whole-body dual-energy X-ray absorptiometry (DXA) and anthropometric measures. The correlation of BMI, BAI, and waist circumference (WC) to DXA adiposity indexes was performed across sex-specific adult and age-and sex-specific child cohorts, using Spearman correlation and linear regression models, respectively. Results: Both BMI and WC had a higher correlation with all adiposity indexes (whole body fat, percent body fat [Bfat%], trunk fat, and percent trunk fat [Tfat%]) measured by DXA than did BAI in both adults and children. Meanwhile, most of the linear regression model associations for BMI with Bfat% and Tfat% had a greater adjusted R-2 than those for BAI among both children and adults. Conclusion: This study indicates that BMI and WC are better tools than BAI for estimating whole body fat and central body fat in a Chinese population.