Call to end 'flawed' use of BMI to diagnose obesity

Doctors are proposing a "radical overhaul" of obesity diagnosis worldwide amid concerns that a reliance on body mass index may be causing millions of people to be misdiagnosed.

- Andrew Gregory Health editor

More than 1 billion people are thought to be living with a condition that for decades has been diagnosed by measuring a person's body mass index (BMI) - their ratio of height to weight - to estimate body fat.

However, the use of BMI alone as a "reliable measure" of an individual's health is being questioned amid fears it could be resulting in both under and overdiagnosis, with "negative consequences" for those affected and wider society.

Dozens of leading experts around the world across a range of medical specialties, including endocrinology, internal medicine, surgery, biology, nutrition and public health, are calling for a "reframing" of a condition causing major harm on every continent and costing countries billions.

Relying only on BMI is "ineffective" because it is not a direct measure of fat, fails to reflect fat distribution around the body and does not provide information about a person's health, according to a report published by the experts in the Lancet Diabetes & Endocrinology journal.