BMI vs BRI what's the difference

BMI or body mass index has so far been a popular measure to classify people in the categories of obese, underweight, and normal weight. However, this health measure may not accurately predict many health risks. Simple to measure, Body mass index (BMI) is calculated by dividing your weight by your height squared. While this can be quite helpful in assessing whether a person is of the right weight or not to a great extent, it may not assess all the health risks accurately.For instance many people with normal BMI may still be at risk of a range of chronic diseases from diabetes to high cholesterol. Wonder why? They may be having unhealthy visceral fat despite having a normal weight. A person with higher BMI may be healthier on the other hand, as they may have more muscle weight. This can be true in case of athletes.

BMI vs BRI

What if there is a more accurate measure to assess mortality risk by way of distinguishing muscle weight and unhealthy fat. BRI or body roundness index is emerging as a more scientific way to estimate obesity and assess whether or not a person would develop metabolic disorders, hypertension and high cholesterol. A new study published in JAMA Network Open, talks about body roundness index, a more precise way to estimate obesity.

While BMI takes into account a person’s body fat using just two measurements, height and weight, BRI also considers hip and waist circumferences to estimate one’s total fat and visceral fat.

Visceral fat or abdominal fat is touted as the most dangerous kind of fat as it is a deep belly fat that even surrounds internal organs.

The problem with BMI

According to a Wall Street Journal report, one of BMI’s biggest flaws is that it doesn’t distinguish between two types of fat—subcutaneous and visceral. It doesn’t identify accurately where the fat is located, something which is essential to understand not just your size but your health.
The World Health Organisation (WHO) established obesity using the anthropometry index as Body Mass Index (BMI) equal to 30 kg/m2 or greater. However, this has its limitations as it cannot truly reflect an individual’s fat distribution and cannot differentiate between fat mass and muscle weight.
Visceral fat can increase risk of diabetes, blood pressure and eventually heart disease.

What is BRI, ABSI and conicity index?

According to International Journal of Environmental Research and Public Health, recent studies have highlighted the association of two new anthropometric indices, the Body Roundness Index (BRI) and A Body Shape Index (ABSI), with the risk of premature death. ABSI is linked to abdominal adipose tissue, with higher values indicating a greater accumulation of fat in the abdominal region, which poses significant health risks. BRI, on the other hand, is associated with visceral adipose tissue and body fat percentage. Although these indices were found to relate to premature death, their connection to cardiovascular diseases (CVDs) was not as strong when compared to traditional measures like BMI and waist circumference.
Another anthropometric index, the Conicity Index, was developed to assess obesity and fat distribution. This index suggests that individuals with higher abdominal fat exhibit a double cone shape, while those with less fat have a cylindrical shape. Incorporating variables like weight, height, and waist circumference, the Conicity Index has been established as an important tool for assessing the risk of heart disease in populations, alongside BRI, by indicating the build-up of fat in the abdominal region.

How to calculate BRI

BRI = 365.2 − 365.5 × √(1 − (((wc/2π)2)/[(0.5 × height)]^2))