Forget BMI. Doctors want to use new BRI system to measure how ’round’ you are – here’s how it works
Experts are recommending a new way to determine your health risks based on your body size – and it has nothing to do with weight.
The measurement, called body roundness index (BRI), is calculated using someone’s height and waist circumference.
Researchers have found that people with the roundest body types may be as much as 163 percent more likely to develop heart disease than their peers who have slimmer waists.
They say BRI may be a more accurate predictor of heart disease and death than using body mass index (BMI).
The body roundness index calculates one’s body size by including their waist circumference and height, unlike the body mass index which uses height and weight. This can give researchers a better idea of the fat distribution in the body, and may be more useful in doctor’s offices, experts say
BMI is a widely used, but recently controversial, measurement that uses someone’s height and weight to determine whether they are underweight, normal weight, overweight, obese or extremely obese.
There’s widespread criticism of BMI as a measurement – mainly that it was developed by studying the wealthy white men, who have different average masses than other demographics.
In addition, studies have shown that where your fat is located on your body may be a bigger influence on your health than the total amount of fat you carry.
BMI can’t account for where fat is located on the body.
Fat that is clustered around your midsection and vital organs has been linked to an increased risk for diabetes, high blood pressure and heart disease.
But fat stored just under the skin, in regions like the legs and buttocks, hasn’t been linked to health risks.
Dr Wenquan Niu, a BRI researcher at the Capital Institute of Pediatrics in Beijing, told The New York Times, abdominal fat is ‘like a silent killer lurking in our body, which can sneak up on a person over years with few noticeable symptoms, especially among apparently lean people: ‘
Dr Niu and his colleague’s research was posted in the Journal of the American Medical Association and it evaluated how well BRI predicted mortality by looking at data from more than 320,900 US adults over a 20 year period.
They sorted the participants into five groups based on their height, weight and waist circumference. Group five had the roundest bodies, group three was the average, and group one had the leanest bodies.
They ruled out the influence of other factors like age, sex, ethnicity, income, tobacco and alcohol use, family history and diabetes.
Even after accounting for these, when looking at the number of deaths in each group – they found that those in the roundest group were 49 percent more likely to have died than those in the average group.
Subcutaneous fat is more visible outside of the body, padding the outer layers of muscle just underneath the skin, and isn’t linked to particular health concerns. Visceral fat, which lies deep amongst the organs, is more dangerous but less noticeable.
Interestingly, those in group one and four were 25 percent more likely to have died than the average group.
Similarly, a study from Nanjing Medical University that was posted in the Journal of the American Heart Association found that having a consistently high BRI over a six year period increased the risk of cardiovascular disease – like heart attack and stroke – by as much as 163 percent.
Study author Dr Yun Qian said that this could be because obesity, and high abdominal fat levels, have been linked to a number of conditions that make someone more likely to develop heart disease, like high blood pressure.
Dr Qian added: ‘BRI measurements may potentially be used as a predictive factor for cardiovascular disease incidence’.
Body Mass Index (BMI) places people into one of five categories based on their height and weight alone. Critics say this measure is imprecise, and can’t account for things like fat distribution and muscle mass – suggesting BRI might be better
The tide began turning against BMI in recent years.
In 2023, the American Medical Association recommended against using it widely in doctors offices.
The organization said there are: ‘issues with using BMI as a measurement due to its historical harm, its use for racist exclusion, and because BMI is based primarily on data collected from previous generations of non-Hispanic white populations.’
This, critics say, is because the tool was built only using data from wealthy white men. Yet it is applied to measure people of all demographics – which critics say makes it imprecise.
Carrie Dennett, a registered dietitian nutritionist with a clinic in the Pacific Northwest, wrote for the Seattle Times: ‘As a measure of individual health, BMI has always been nonsense.’
They point out that BMI also can’t distinguish between weight from muscle and fat. Because of that, you get misleading results, like highly-muscled athletes being ranked as obese, Ms Dennett said.
Still, BRI isn’t perfect, she said: ‘BRI is “better” than BMI, but it still perpetuates weight-centric health care.’
