The American Medical Association (AMA) has voted to move away from using the Body Mass Index (BMI) as the sole determinant of health.
One of the nation’s largest professional organizations representing physicians ushered in a new policy this month that takes a more comprehensive approach to assessing weight and health.
BMI readings have long been a standard method used by physicians to determine whether an individual is of a healthy weight by dividing their weight by the square of their height.
“The BMI is just a very poor measure of general health,” explained Dr. Scott Hagan, an assistant professor at the University of Washington and expert in obesity, according to The New York Times. “Someone with an elevated BMI may be perfectly healthy.”
For instance, two different individuals might share the same BMI despite one being obese and the other having a high amount of muscle.
For a more accurate understanding of an individual’s weight, AMA now recommends that healthcare providers take other measurements into consideration.
One of these is the body adiposity index, which looks at an individual’s height in relation to their hip circumference to help calculate body fat.
Another factor AMA says is important to consider is an individual’s amount of visceral fat, which is a fatty tissue that tends to be stored in the midsection and around the organs.
Having a high percentage of visceral fat — which is common for those who are obese — carries a heightened risk of a metabolic disorder like type 2 diabetes, heart disease, cancer, dementia, and more.
Obesity is a growing problem worldwide, with experts like the World Obesity Atlas predicting that 51% of people — over 4 billion — will be obese by 2035, as covered in The Dallas Express.
While AMA’s vote only carries a recommendation for other health professionals to follow, the shift away from using BMI alone to prescribe weight loss solutions for individuals is significant.
Noting that BMI is “not this magic or powerful number that dictates how healthy or sick you’re going to be,” a professor at the University of California, Los Angeles, A. Janet Tomiyama told the NYT she had long wondered “why really smart physicians continue to rely on something that was so clearly flawed.”
Yet some experts were quick to precise that while the shortcomings of BMI should be taken into consideration by practitioners, the metric can be useful in some cases.
For instance, Iliya Gutin, a research affiliate at the University of Texas at Austin, noted it was an inexpensive and systematic way to assess large numbers of people, according to the NYT.
It also remains deeply embedded in health standards and guidelines, meaning displacing it won’t be easy, Gutin added.
Nevertheless, the metric has seen some recent tweaks.
As covered in The Dallas Express, BMI growth charts for children were expanded by the Centers for Disease Control and Prevention late last year.
Compared with the U.S. surveys conducted from 1963 to 1994 that were previously based on, the surging rates of childhood obesity have necessitated the revision.