Evaluation of body adiposity index (BAI) to estimate percent body fat in an indigenous population.

Background & Aims: The aim of this study was to evaluate the usefulness of Body Adiposity Index (BAI) as a predictor of body fat in Xavante Indians and to investigate which anthropometric measures of adiposity best correlate with body fat in this population.

Methods: We evaluated 974 individuals (476 male), aged 42.3 ± 19.5 years. Percentage of body fat (%BF) determined by bioimpedance analysis (BIA) was used as the reference measure of adiposity. Bland-Altman analysis was used to assess the agreement between the two methods: BAI and BIA. Associations between anthropometric measures of adiposity were investigated by Pearson correlation analysis.

Results: BAI overestimates %BF (mean difference: 4.10%), mainly at lower levels of adiposity. Significant correlations were found between %BF and all measurements, being the strongest correlation with BAI. However, stratified analyses according to gender showed that among men waist circumference has the strongest correlation (r = 0.73, p < 0.001) and among women BAI (r = 0.71, p < 0.001), BMI (r = 0.69, p < 0.001) and waist circumference (r = 0.70, p < 0.001) performed similarly.

Conclusion: BAI can be a useful tool to predict %BF in Xavante Indians, although it has some limitations. However, it is not a better predictor of adiposity than waist circumference in men or BMI and waist circumference in women.