ISTANBUL

A new study has suggested that redefining obesity could dramatically reshape how widespread the condition appears in the US.

ABC News reported on Monday that the research published in JAMA Network Open found that more than 75% of US adults may meet criteria for obesity when waist-based measurements are added to body mass index (BMI), compared with about 40% under BMI alone.

The analysis was conducted by researchers from Beth Israel Deaconess Medical Center, Harvard University, Yale University, and Yale New Haven Health, using federal health data collected between 2017 and 2023.

“BMI is the standard measure for determining criteria for obesity. It’s the most widely known metric,” said Dr. Erica Spatz, a cardiologist at Yale School of Medicine and a co-author of the study, in comments to ABC News.

She warned that BMI overlooks adipose tissue, which she said “is more associated with high blood pressure, diabetes, and heart disease.”

‘Most significant chronic disease’

The findings draw on a revised obesity definition proposed earlier this year by The Lancet Diabetes & Endocrinology Commission, which incorporates waist circumference and related ratios and has been endorsed by more than 70 medical organizations worldwide.

Applying those criteria to data from over 14,000 participants representing nearly 238 million US adults, researchers estimated that 75.2% would qualify as having obesity.

Dr. Fatima Cody Stanford of Massachusetts General Hospital and Harvard Medical School, who was not involved in the study, said the results underscore the scale of the issue.

“We do have a major problem. Obesity is by far the most significant chronic disease in human history,” she told ABC News.

The authors cautioned that broader adoption of the new definition will require further research, noting limitations in the data and the need for age-specific thresholds, particularly for older adults.