Why The CDC Just Updated Its BMI Chart For Kids And Teens

Categorized across three different classes, a 2018 scientific review published in Endotext highlights that obesity is a chronic disease. Obesity has been linked with an increased risk for certain health conditions, including heart disease and type 2 diabetes. Although it cannot exclusively determine a patient's health status (via U.S. Centers for Disease Control and Prevention), many clinicians utilize body mass index (BMI) charts as a tool to calculate a patient's growth over time based on their weight and height in comparison to those of the same gender or age group, reports Healthline.

On December 15, the CDC released a media statement announcing that they had extended BMI growth charts for children and teens ages 2 through 19 to include higher BMI percentiles to account for severe obesity. Those with severe obesity are defined as having a BMI of 120% (or more) of the 95th percentile. "Childhood obesity is a serious and increasing problem in the United States," director of the CDC's National Center for Chronic Disease Prevention and Health Promotion, Dr. Karen Hacker, said via the statement. "Intervening early is critical to improving the health of our children as they grow into adults." By extending the growth charts, the CDC states they will be better able to provide treatment specific to children and adolescents with severe obesity.

Dr. Elizabeth Davis, Pediatric Sports Medicine Physician at Orlando Health Arnold Palmer Hospital for Children, explained to Healthline the ways in which BMI growth charts as a screening tool can be beneficial for physicians. "BMI growth charts serve a role for overall growth tracking during childhood and adolescence, and can be useful to know when to screen for potential health problems such as diabetes and high blood pressure," she told the publication.

However, experts stress that a multi-faceted approach is needed to adequately assess a patient's health status and state that BMI growth charts do not give us a full comprehensive picture alone. For instance, BMI charts do not factor in muscle mass, societal influences, or genetics, notes Healthline. Additionally, as outlined in the previously mentioned 2018 scientific review, obesity is defined as "when excess fat accumulation (regionally, globally, or both) increases risk to health." Yet researchers specify that the point at which obesity poses a risk to one's health varies across demographic groups. 

Furthermore, researchers from a 2019 case study published in Transgender Health point out that determining a healthy BMI based on factors, such as gender, can potentially lead to the misdiagnoses of weight-related disorders in transgender youth. For this reason, the researchers stress the importance of factoring in a patient's affirmed gender and sex assigned at birth in the creation of BMI growth charts.