Body adiposity index

The body adiposity index (BAI) is a method of measuring the amount of body fat in humans. The BAI is calculated without using body weight, unlike the body mass index (BMI). Instead, it uses the size of the hips compared to the person's height.

Based on population studies, the BAI is approximately equal to the percentage of body fat for adult men and women of differing ethnicities.

The BAI is calculated as:

${\displaystyle {\frac {100\times {\text{hip circumference in m}}}{{\text{height in m}}\times {\sqrt {\text{height}}}}}-18}$

Hip circumference (R = 0.602) and height (R = −0.524) are strongly correlated with percentage of body fat. Comparing BAI with "gold standard" dual-energy X-ray absorptiometry (DXA) results, the correlation between DXA-derived percentage of adiposity and the BAI in a target population was R = 0.85, with a concordance of C_b = 0.95.

The BAI could be a good tool to measure adiposity due, at least in part, to the advantages over other more complex mechanical or electrical systems. Probably, the most important advantage of BAI over BMI is that weight is not needed. However, in general it seems that the BAI does not overcome the limitations of BMI.

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