Body shape index

The inclusion of WC is believed to make the BSI a better indicator of risk of mortality from excess weight than the standard body mass index.

[2][3] ABSI correlates only slightly with height, weight and BMI, indicating that it is independent of other anthropometric variables in predicting mortality.

[5] A high ABSI appears to correspond to a higher proportion of central obesity, or abdominal fat.

In a sample of Americans in the National Health and Nutrition Examination Survey, death rates in some subjects were high for both high and low BMI and WC, a familiar conundrum associated with BMI.

The linear relationship was unaffected by adjustments for other risk factors including smoking, diabetes, elevated blood pressure and serum cholesterol.

The equation for ABSI is based on statistical analysis and is derived from an allometric regression.

The ABSI means and standard deviations are age- and sex-dependent empirically determined and tabulated.

The following diagram shows the progression of risk groups as a function of weight and waist circumference using the example of a 35-year-old man.