BRI vs height (vertical axis) vs waist circumference (horizontal axis).
BRI is a calculated geometric index used to quantify a person’s individual body shape, that provides a rapid visual and anthropometric tool for health evaluation.
The BRI models the human body shape as an ellipse, with the intent to relate body girth with height to determine body roundness.
With BRI weight isn’t part of the equation.
It uses a tape measure to obtain waist circumference and height, which are then combined with an ellipse factor before computation by an automatic calculator.
Waist circumference and, optionally, hip circumference are measured, along with height, and plugged into a formula to estimate visceral adipose tissue, the abdominal fat that is associated with cardiovascular disease, diabetes, and hypertension.
The BRI calculation can be used to estimate total and visceral body fat.
It accurately classify people with healthy fat mass (weight) compared to obese people who are at risk for morbidities.
Compared to body mass index (BMI), which uses only two metrics (weight and height), BRI may improve predictions of the amount of body fat and the volume of visceral adipose tissue.
BMI can misclassify individuals as obese because it does not distinguish between a person’s lean body mass and fat mass.
By comparison with BMI, BRI quantifies body girth in relation to height, potentially providing more accurate estimates of fat mass.
BMI does not account for variations based on age sex, race or ethnicity and doesn’t differentiate between body composition changes between pre-and post menopausal status, and Asian populations tend to have obesity related health problems at lower BMI‘s.
BRI scores range from 1 to 16, with most people between 1 and 10.
People with scores of 6.9 and up – indicating wider, rounder bodies – were found to have a risk of all-cause mortality that was increased by up to 49% compared to people having a medium BRI of 5.
High BRI was associated with increased risk of metabolic syndrome.
American adult BRI values range from 3 or less with midsection leanness to 7 or more with midsection roundness, with a medium index of about 5.
With BRI the human body shape is visualized as an egg or ellipse rather than as a cylinder envisioned in the concept of the BMI.
The degree of circularity of an ellipse is quantified by eccentricity, mapping eccentricity in a range of 1 to 20.
Body roundness shapes vary across a range of people who are lean (BRI less than 3) to severely obese (BRI more than 12).
The only device needed to determine BRI is a measuring tape: circumference of waist and determination of height.
These values are factored with an eccentricity equation in a calculator.
Human body and fat mass data from the United States National Health and Nutrition Examination Survey (NHANES) database found that BRI never was a negative value, and that larger BRI values are associated with people having a round shape, while shape values closer to 1 were related to people with narrow, lean bodies.
The maximum observed BRI value in the NHANES data was 16.
BRI had similar accuracy in predicting percentage body fat and percentage fat volume as the BMI.
The BMI has numerous drawbacks, as it is unable to distinguish between muscle and fat, is inaccurate in predicting body fat percentage, and has poor ability to predict the risk of heart attack, stroke or death.
The BRI and abdominal value index are most effective at predicting risk of developing nonalcoholic fatty liver disease (NAFLD).
The BRI has proved effective in identifying risk of death from different diseases, disorders of metabolic syndrome, liver disease, cardiovascular diseases in association with sarcopenia, and bone mineral density.
BRI s a better indicator than the BMI and body shape index for predicting the risk of hypertension, dyslipidemia, and hyperuricemia in Chinese women.
The 2 measurements of the BRI – waist circumference and hip circumference – are subject to high variability in standing obese people.
Such variability may indicate differences in fat distribution in people with excessive visceral fat, causing errors in BRI.
Diagnostic factors for diseases associated with obesity, such as ethnicity, family history, dietary habits, and physical activity, are not factored into the BRI. Place on site BRI