Research: Body mass index alone is not sufficient in the definition of obesity

A joint study by researchers from China, Britain, the US, and Spain, published in the journal Nature, revealed that relying solely on body mass index (BMI) in diagnosing obesity is insufficient and can lead to incorrect classifications.

Examining data from 844,108 adults across four countries, the research emphasized that obesity cannot be determined solely by a BMI of 30 kg/m2 or higher. The study evaluated the condition in two separate categories: "clinical obesity," which causes impairment in organ functions, and "pre-clinical obesity." The data showed that using only BMI led to 1.2% to 3.1% of participants being overclassified as obese, and 5.2% to 8.6% being underclassified. When waist circumference and waist-to-height ratio were evaluated, the prevalence of obesity was found to increase by 3.3% to 7.4% depending on the country.

Researchers recommended evaluating body fat percentage through measurements such as waist circumference in addition to BMI during the diagnosis stage, and taking weight-related organ dysfunctions such as heart or liver problems into account. Evaluating the issue, Prof. Dr. Francesco Rubino stated that body mass index alone cannot show whether a person is sick or what kind of care they need, noting that this situation can lead to individuals receiving both insufficient and excessive treatment.