Understanding obesity in middle-aged and older adults
A recent study presented at the European Congress on Obesity proposes a shift in the standard classification of obesity for people over 40. Traditionally defined by a body mass index (BMI) of 30, researchers suggest that obesity could be identified with a BMI over 27 for this age group.
The flaws of BMI as a health indicator
The study, which analyzed body fat percentage and BMI of adults in Italy, revealed that many individuals over 40 had obesity based on body fat despite not meeting the traditional BMI threshold. As people age, their body composition and fat-to-muscle ratio change, making BMI a less accurate measure of obesity.
Proposed new BMI standards for older adults
Marwan El Ghoch, MD, and his team found that the most suitable BMI cut off for identifying obesity in middle-aged and older adults was 27.08 kg/m² for women and 27.36 kg/m² for men. This new threshold could potentially redefine obesity status for a larger portion of the population, particularly in the U.S., where approximately 45% of adults aged 40 to 59 and 43% over 60 are estimated to have obesity.
Limitations and broader implications
While the study’s findings are compelling, they are not without limitations, including the need for broader research across different populations. Moreover, the study did not consider factors like diet, physical activity, and sleep health, which can influence obesity risk.
Alternatives to BMI
Experts suggest that other methods, such as waist circumference measurements, physical fitness assessments, and body composition analyses, provide a more comprehensive view of an individual’s health. These alternatives could better reflect the changes in body composition that occur with aging.
Conclusion
Although BMI has been criticized, it remains a useful tool for assessing health risks. The study contributes to the ongoing discussion about BMI’s limitations and the need for additional measures to assess health, particularly in older adults.
