At the Annual Meeting of the American Medical Association (AMA) House of Delegates, a policy was adopted to provide clarity on the use of body mass index (BMI) as a measure in medicine. The policy addresses limitations and flaws of BMI and encourages doctors to use additional factors to assess health in patients.
“This official statement is that the BMI metric is a flawed indicator of overall health,” says Dr. Samer Mattar, a bariatric surgeon at the Weight Loss and Metabolic Center at Baylor Medicine. “The report recommends clinicians should consider other factors, in addition to the BMI, when assessing a patient’s risk for obesity-related diseases.”
This new policy was developed as part of the AMA Council on Science and Public Health report, which examined the problematic history of BMI and explored alternative approaches. The report highlighted the limitations and benefits of using BMI, emphasizing that it is an imperfect method for measuring body fat across different racial/ethnic groups, genders, sexes and age groups. Because of the downfalls of using BMI, the policy aims to educate physicians about the shortcomings of BMI and alternative measures for diagnosing obesity.
Under the newly adopted policy, the AMA acknowledges the issues associated with relying solely on BMI as a measurement. It recognizes the historical harm caused by BMI, its use in perpetuating racist exclusion and its reliance on data primarily collected from non-Hispanic white populations.
The AMA recommends using it in conjunction with other valid risk measures, such as visceral fat measurements, body adiposity index, body composition assessments, relative fat mass, waist circumference and genetic/metabolic factors.
The policy acknowledges that BMI is generally correlated with fat mass in the overall population, but its predictability diminishes when applied to individuals. The AMA also acknowledges the importance of considering relative body shape and composition differences among different racial/ethnic groups, genders, sexes and age groups when using BMI as a measure of adiposity. Finally, the policy emphasizes that BMI should not be the sole criterion for denying insurance reimbursement.
“Obesity, similar to other diseases, is a multifaceted condition that cannot be fully assessed using a single measurement,” Mattar says. “Some individuals with a higher BMI may not exhibit any signs of diseases commonly associated with excess weight, such as hypertension, obstructive sleep apnea or type 2 diabetes. However certain individuals with only slightly elevated BMI levels may have these and other underlying metabolic disorders that could potentially be improved through weight loss. That’s why it’s so important to consider more factors than just BMI.”
By Tiffany Harston, communications associate with the Michael E. DeBakey Department of Surgery