The well-known BMI or Body Mass Index, which is calculated as weight in kilograms divided by height in meters squared, or as [weight(pounds)/ height (inches) Squared] x 703, has been used as a measure of obesity and a correlate of metabolic diseases (diabetes, hypertension, cardiovascular disease, etc.). Using this table, my BMI is 22, which is in a good range.
But the type of fat which is a strong risk factor with metabolic disease and mortality is the visceral fat or technically- and euphemistically-speaking “intraabdominal adipose depot.” The more visceral fat we have, the more egg-shaped we become and the father we are from the hypothetical cylindrical shape used in BMI calculations. Also, as seen in the image, three people having the same exact BMIs and heights could have very different body shapes and visceral fat.
With the obesity on the rise, researchers have developed a new indicator of visceral fat which takes into account the oval (elliptical or egg) shape of modern humans. Body Roundness Index (BRI) is an innovative health metric that helps determine the roundness of your body shape from your height, waist and hip circumference, and calculated as:
364.2 − 365.5 × √(1 − [waist circumference in centimeters / 2π]2 / [0.5 × height in meters]2)
The BRI ranges between 1 to 20 (1 = narrow body, 20 = more round) and was found to correlate well with measurements taken by Bioelectrical Impedance Analysis.
The following from a recent JAMA paper describes the concept and trends:
Numerous studies have demonstrated that obesity as defined by BMI was significantly associated with high risk of all-cause mortality compared with BMI within the reference range. With the extensive investigation of body composition, more attention has been paid to the association between visceral obesity and mortality. It is widely recognized that body fat content cannot be characterized by BMI. For instance, among individuals with the same BMI, fat distribution and body composition varied dramatically. A health check-up cohort study of 36 656 participants by Lee et al found that body fat distribution as reflected by visceral-to-subcutaneous fat area ratio was more consistently associated with of all-cause mortality than overall adiposity as reflected by BMI..
To better embody fat distribution, a newer anthropometric measure, body roundness index (BRI), was coined by Thomas et al, who developed elliptical models based on human body shape to calculate body roundness and used eccentricity to estimate visceral fat and total body fat percentages. Besides weight and height, BRI additionally considers waist circumference, and hence it can more comprehensively reflect visceral fat distribution. BRI was found to be superior over other anthropometric indicators in estimating the risk for various clinical end points, including cardiometabolic disease, kidney disease, and cancer. Furthermore, longitudinal studies have shown that high BRI was associated with the significantly increased risk of all-cause mortality and cardiovascular disease-specific mortality…
Data collected between 1999 and 2018 show that mean BRI increased from 4.80 to 5.62 and the trend was more obvious among women, elderly individuals, and individuals who identified as Mexican American. By race and ethnicity, BRI was highest among Mexican American participants, followed by non-Hispanic Black participants and non-Hispanic White participants. By education, adults with college graduate degree or above had the lowest BRI, and in a sharp contrast, the highest BRI was consistently seen for adults with education less than 9th grade.
![The Association Between Body Roundness Index and All-Cause Mortality Risk After Full Adjustment The Association Between Body Roundness Index and All-Cause Mortality Risk After Full Adjustment](https://substackcdn.com/image/fetch/w_1456,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F7667c24b-bfea-4d0d-abb2-d5bffb85bb5c_810x756.png)
By cigarette smoking, mean BRIs were comparable before 2009, but increased significantly in smokers compared with nonsmokers afterwards. It is not known what caused this major shift. One possibility is the increasing weight of teenagers and adolescents who have adopted smoking since 2009.
But Lower BRI Does not Mean Lower All-Cause Mortality
Interestingly, although BRI seems to be helpful in estimating the onset of diabetes or the risk for incident cardiovascular events, all-cause mortality risks do not have a linear relationship with BRI, as they increase for BRIs lower than 3.4 and higher than 6.9. It appears that being too slender is a risk factor if it is accompanied with low muscle mass, as in in elderly populations. According to the article:
In this national cohort, we noticed that very low BRI was associated with a significantly increased risk of all-cause mortality, especially in individuals aged 65 years and older. This association seems plausible, as BRI was identified as a potential proxy measure associated with nutritional status, and very low BRI can be accompanied with malnutrition, fatigue, reduced activity tolerance, and muscle atrophy. The reasons behind the association between BRI and mortality may be epidemiologically and clinically plausible. From epidemiological aspects, elevated BRI was significantly associated with an increased risk of cardiovascular and metabolic disorders, and even cancer, which might serve as the culprits responsible for all-cause mortality. From clinical aspects, the accumulation of visceral fat was associated with more profound insulin resistance and an increased risk of cardiometabolic diseases, even among participants with weight within reference range.
You can use websites like this one to calculate your BRI. The BRI outputs a graph of body shape with reference to a healthy zone.
Thank you for this... it is like the lipogram's interpretation.