Should we abandon BMI and use body roundness index instead?

The Body Mass Index (better known as BMI) has long been used to quickly and easily get a snapshot of a person’s body fat levels. To calculate a person’s BMI, divide their weight in kilograms by their height in meters times themselves. The resulting number is used to determine a person’s health risk.

Nevertheless, there are much better ways Obtaining an accurate measurement of a person’s body fat levels – such as using dual-energy x-ray absorptiometry (Dexa) or magnetic resonance imaging (MRI) – is very resource-intensive. This could explain why BMI has remained the most widely used method for measuring health since it was first used in the latter part of the years. 20th century.

But many health experts believe BMI does significant limitationsespecially for children and young people (whose body fat levels change as they grow), athletic people (who have high muscle mass) and people from ethnic minority groups (who may develop health problems at lower body fat levels).

BMI was never created for healthcare use and was developed from data collected from European people in the 19th century. although child- and ethnicity-specific adjusted BMI and alternative length and weight Ratios have been proposed, but none have made sufficient progress to improve BMI’s reputation.

Several alternatives to BMI have also been proposed, such as use waist to hip ratio (waist circumference divided by hip circumference) or body volume index (which uses 3D body scanners to estimate total body fat distribution).

But one recent research suggests that instead of BMI we should use something called ‘ body roundness index (BRI) to get a more accurate picture of a person’s body fat levels and predict health risks.

What is the body roundness index?

BRI was developed by American researchers in 2013 in response to criticism of BMI. Instead of looking at height and weight, BRI quantifies body fat level mathematically by looking at height and waist circumference. This produces a value that typically ranges from one to 20. It is the lowest and highest values ​​that suggest the highest health risk.

Numerous studies have shown that BRI may be better than BMI at predicting the health risks associated with different levels of body fat. This includes predicting the risk of weight-related diseases, such as cardiovascular disease, diabetes, kidney disease And cancerlike death from any cause.

This latest study, which surveyed 32,995 U.S. adults between 1999 and 2018, found a link between BRI and death from any cause. Specifically, they also found that people with the lowest and highest BRI scores had the greatest health risks.

They also found that BRI was better than BMI at accurately detecting this risk. This is because BRI takes into account the fat retained around the abdomen, which is related to it greater risk of health problems. This is different from BMI, which only takes total weight into account.

BRI vs BMI

Because BRI only requires a tape measure and a mathematical equation, this means it is as easy to use and accessible as BMI. But assuming the BRI is measured manually, it remains as subject to human error as the BMI.

In fact, one study found that eight out of 10 trained health professionals demonstrated this high levels of human error when manually measuring the abdomen, they did not notice an increase of 3 cm the second time they took the measurement. This margin of error is likely to be even greater for people who take their own measurements at home.

As a new measure, BRI also does not yet have the kind of extensive data supporting its use that exists for BMI. This makes it harder to know how effective and reliable it is compared to these more established methods.

And just like BMI, BRI is a composite measure– meaning it combines multiple closely related measures into a single index. This makes it very difficult to tease out the impact that different body fat levels can have on health – and can lead to misleading interpretations of the results.

Although BRI can improve some of the shortcomings of BMI, it is not immune to misclassification. For example, people with high muscle mass may still experience inaccuracies in their assessment of health risks if their body fat distribution does not match “typical” patterns around the abdomen. Research also shows that BRI’s accuracy in predicting health risks may vary depending on a person’s ethnicity, age and gender.

BRI certainly represents an advancement in the hunt for a more accurate alternative to BMI by focusing more on body shape and fat distribution rather than just body size. But it still has its limitations. While this latest study gives us more data on BRI’s accuracy, more research is still needed before we can be confident that it is better than BMI and should replace it.

Perhaps an even better way to get a picture of a person’s health is to use 3D body surface imaging. This creates a scaled 3D digital image of the human body that allows healthcare professionals to explore all potential existing body measurements, including both BRI and BMI, and allows us to explore new digital alternatives.

But regardless of which body measurement you or a doctor may use to assess your health, it’s important to remember that each person is unique, and our bodies always come in a wide range of shapes and sizes (and should).

This article is republished from The conversation under a Creative Commons license. Read the original article.