BMI Measurement in Schools: Relevant or Not?

With growing obesity rates among U.S. children, many schools have sought to implement programs and policies that promote healthy eating and physical activity. Much attention has also focused on the benefits of school involvement with body mass index (BMI) measurement programs. 

With guidance from an expert panel, the Centers for Disease Control and Prevention (CDC) developed a report on BMI measurement programs to help inform decision-making.  The report raises important questions, such as:

1) What is the main purpose of BMI measurement programs?;

2) What have been the outcomes of BMI measurement programs in schools?;

3) Should it be done or not? What are some current recommendations?; and

4) What are some of the concerns being raised due to BMI measurement programs?

According to the report, BMI measurement programs in schools may be conducted for surveillance and screening purposes.  BMI surveillance data, which are typically anonymous, can be used to assess the weight status of a specific population to identify the percentage of students who are potentially at risk for weight-related health problems as well as to help monitor the outcomes of interventions.  Conversely, BMI screenings identify those at risk and provide parents with information to help them take appropriate action. 

Currently, there is no consensus on the value of BMI measurements.  According to the report, the U.S. Preventive Services Task Force concluded that insufficient evidence exists to recommend for or against BMI screening programs as a means to prevent adverse health outcomes; nevertheless, the American Academy of Pediatrics (AAP) recommends that BMI should be calculated annually on all youth as part of normal health supervision, and the Institute of Medicine recommends annual school-based screening. 

There are some concerns surrounding BMI measurement programs.  More research is needed to determine whether these programs are a promising approach for addressing obesity among children and adolescents.  In addition, some believe that BMI screening programs might stigmatize students and lead to harmful behaviors, or that they might be ineffective, waste scarce health promotion resources, and distract attention from other school-based obesity prevention activities.

The report recommends that schools that initiate BMI measurement programs have a safe and supportive environment for students of all body sizes and strategies to promote healthy eating and physical activity.  In addition, schools should ensure that parents receive a clear and respectful explanation of results of BMI screening programs and appropriate follow-up actions.  Other recommendations to reduce the risk of harming students are available in the report. 

The report was published in the December 2007 issue of the Journal of School Health.  The full journal article is available online at: http://www.ashaweb.org/pdfs/joshfinal_249_07nov27.pdf. To access the report’s Executive Summary, please visit http://www.cdc.gov/HealthyYouth/overweight/BMI/pdf/BMI_execsumm.pdf.

Source: "Body Mass Index Measurement in Schools - BMI, Executive Summary," CDC, December 2007.