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Body Metrics

Body Roundness Index Calculator

Geometric eccentricity model predicting visceral adiposity and all-cause mortality

Input Parameters
Real-time calculation updates dynamically as you adjust inputs. Values remain strictly local on your device.
Body Roundness Index (BRI)Healthy Roundness (Lowest mortality)
2.8

Lowest mortality risk observed clinically between 3.0 and 5.0

Waist-to-Height Ratio
0.47
Clinical Responsibility Note: This calculation provides statistical estimations for informational and educational purposes only. It is not an individualized medical diagnosis or clinical prescription.

Mathematical Formula & Scientific Methodology

Formula: Thomas Body Roundness Index (BRI)

BRI = 364.2 - 365.5 × √[1 - (waist / 2π)² / (0.5 × height)²]

Estimates the eccentricity of human body cross-section, with higher values reflecting spherical roundness driven by visceral fat accumulation.

Model Assumptions

  • Torso cross-section conforms to an elliptical cylinder

Variables & Standard Units

SymbolPhysiological MeaningUnit
waistWaist circumferencecm
heightStanding heightcm

Scientific Limitations

  • Valid for adult statures

Peer-Reviewed Scientific Citations

Relationships between body roundness with body fat and visceral adipose tissue (2013)

Thomas DM, Bredlau C, Bosy-Westphal A, et al. (2013) — Obesity, 21(11), 2264-2273

Key Finding: Body Roundness Index (BRI) models human body as an ellipse using waist and height, outperforming BMI in estimating visceral adiposity and all-cause mortality risk.

Frequently Asked Questions

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