Obesity and BMI: Experts want to branch out from controversial metric
Global News
A group of global experts is proposing a new way to define and diagnose obesity, reducing the emphasis on the controversial body mass index.
A group of global experts is proposing a new way to define and diagnose obesity, reducing the emphasis on the controversial body mass index and hoping to better identify people who need treatment for the disease caused by excess body fat.
Under recommendations released Tuesday night, obesity would no longer be defined solely by BMI, a calculation of height and weight, but combined with other measurements, such as waist circumference, plus evidence of health problems tied to extra pounds.
Obesity is estimated to affect more than one billion people worldwide. In the U.S., about 40 per cent of adults have obesity, according to the U.S. Centers for Disease Control and Prevention.
“The whole goal of this is to get a more precise definition so that we are targeting the people who actually need the help most,” said Dr. David Cummings, an obesity expert at the University of Washington and one of the 58 authors of the report published in The Lancet Diabetes & Endocrinology journal.
The report introduces two new diagnostic categories: clinical obesity and pre-clinical obesity.
People with clinical obesity meet BMI and other markers of obesity and have evidence of organ, tissue or other problems caused by excess weight. That could include heart disease, high blood pressure, liver or kidney disease or chronic severe knee or hip pain. These people would be eligible for treatments, including diet and exercise interventions and obesity medications.
People with pre-clinical obesity are at risk for those conditions, but have no ongoing illness, the report says.
BMI has long been considered a flawed measure that can over-diagnose or underdiagnose obesity, which is currently defined as a BMI of 30 or more. But people with excess body fat do not always have a BMI above 30, the report notes. And people with high muscle mass — football players or other athletes — may have a high BMI despite normal fat mass.
