New Criteria for Obesity
Researchers at Mass General Brigham have proposed a major update to the definition of obesity that would classify nearly 70% of U.S. adults as obese. The new benchmark adds waist and body fat measurements to BMI, showing body fat locations rather than just total body weight.
The Impact of New Criteria
With these new criteria, the estimated U.S. obesity rate increases from 42.9% to nearly 70% after studying 300,000 people. This means that a number of people who may once have been considered healthy are actually at higher risk for conditions such as heart disease and diabetes. The increase was highest among older adults, with nearly 80% of participants over 70 reaching the obesity mark.
Limitations of BMI-Based Approach
The study highlights the limitations of a BMI-based approach that doesn’t take into account how fat stored throughout the body can predict overall health. Co-first author of the study noted that the findings are significant, and that with 70% of the adult population now estimated to have excess fat, there is a need to better understand which treatment approaches to prioritize.
Risks Associated with Abdominal Fat
The accumulation of abdominal fat, known as visceral fat, has long been considered metabolically detrimental. It is also associated with an increased risk of conditions such as diabetes, dyslipidemia, hypertension, and cardiovascular disease. Redefining obesity to include patients with a high-risk fat distribution could help focus more clinical attention and resources on this vulnerable group.
Importance of Body Composition
Experts suggest that focusing solely on weight can obscure who is really at risk, and contributes to stigma while distracting from the real problem of metabolic health. Tools that assess body composition, waist circumference, and markers of insulin resistance give a far more accurate picture than the scale ever could. It is essential to shift the discussion from weight alone to body composition and fat distribution to provide more personalized and effective care.
Future Implications
As GLP-1 drugs expand, the obese population is likely to improve. However, if the discussion does not shift from weight alone to body composition and fat distribution, there will be a continued misjudgment of risks and missed opportunities for more personalized care. It is crucial to consider the distribution of body fat, rather than just the total body weight, to accurately assess health risks and provide effective treatment.
