Relationships between body roundness with body fat and visceral adipose tissue emerging from a new geometrical model

TLDR

The study develops a new geometrical index combining height, waist, and hip circumference to predict total and visceral body fat. Using two elliptical body models, the authors compute a body roundness index from eccentricity and regress it against DXA and MRI measures to estimate %body fat and %VAT. The body roundness index modestly improves prediction of %body fat and %VAT over BMI, WC, or HC, defines healthy ranges, and is available as an automated graphical tool.

Abstract

To develop a new geometrical index that combines height, waist circumference (WC), and hip circumference (HC) and relate this index to total and visceral body fat.Subject data were pooled from three databases that contained demographic, anthropometric, dual energy X-ray absorptiometry (DXA) measured fat mass, and magnetic resonance imaging measured visceral adipose tissue (VAT) volume. Two elliptical models of the human body were developed. Body roundness was calculated from the model using a well-established constant arising from the theory. Regression models based on eccentricity and other variables were used to predict %body fat and %VAT.A body roundness index (BRI) was derived to quantify the individual body shape in a height-independent manner. Body roundness slightly improved predictions of %body fat and %VAT compared to the traditional metrics of body mass index (BMI), WC, or HC. On this basis, healthy body roundness ranges were established. An automated graphical program simulating study results was placed at http://www.pbrc.edu/bodyroundness.BRI, a new shape measure, is a predictor of %body fat and %VAT and can be applied as a visual tool for health status evaluations.