Prevalence of obese US adults could nearly double in percentage under new definition: Study

A team of researchers from Beth Israel Deaconess Medical Center, Harvard University, Yale University and Yale New Haven Health, found that BMI alone may significantly underestimate how many U.S adults have obesity. The new study has revealed that more than 75% of US adults may meet the criteria for obesity under new conditions. The rise is almost double in percentage because when BMI is considered, only 40% of US adults fall under obese category. The new definition uses a waist-based measurement and includes waist circumference, waist-to-hip ratio and waist-to-height ratio. For the study, published in JAMA Network Open, the team used data from the National Health and Nutrition Examination Survey, a national survey run by the Centers for Disease Control and Prevention that measures the health and nutrition of adults and children in the U.S. The team looked at data from more than 14,000 participants representing 237.7 million adults between 2017 and 2023, applying the Lancet Commission's proposed obesity criteria along with BMI.They found an estimated 75.2% of U.S. adults met criteria for obesity using BMI and additional body measurements compared to 40% when BMI alone was reviewed.The authors noted that the study has limitations. And because nearly all adults age 50 and older were classified as having obesity under the new definition, age-specific thresholds are needed as well.The authors did highlight the limitations of BMI as a standalone screening tool and suggest that incorporating waist measurements could improve obesity detection.They also stressed that because the new criteria will likely raise the current obesity estimates, more research should be done before broadly adopting the new definition.