Study: BMI Reports Don’t Improve Student Health

Schools across the nation track students’ body mass index (BMI) and report those figures to the students’ parents. But the results of randomized controlled trial, the Fit Study, conducted by the UC Berkeley School of Public Health, show that sending BMI reports to parents does not improve students’ weight status and may increase students’ body dissatisfaction.

Click image to download PDF of Fit Study Policy Brief.

Twenty-five states require schools to measure BMI of students and nine states require those BMIs to be reported to parents. Elevated BMI is a risk for developing diabetes and heart disease.

“Our study was designed to help schools make evidence-based decisions about conducting BMI screening and reporting,” Kristine Madsen, lead author on the study and public health nutrition and community health sciences professor at the Berkeley Public Health, said. “It’s clear that there is no value in sending BMI reports to parents, and the practice of weighing students at school does have unintended consequences.”

The Fit Study, is the first of its kind, looked at what types of impacts BMI screenings might have. Over the course of three years, researchers surveyed 30,000 elementary and middle school children in California. These students were split into three groups, one in which children had a BMI screening with a report sent to their families; another in which children only had the screening; and the final group in which there were no screenings at all. 

Researchers found that BMI reports did not reduce obesity rates in students between 3rd and 8th grade. Most families either forgot the report or simply learned nothing new from it. However, one-third of students were uncomfortable with being weighed at school. Students also reported increased body dissatisfaction, although there were no increases in weight-based bullying or efforts to control weight, such as skipping meals. 

The study found that students preferred to be weighed by nurses in private, rather than by teachers surrounded by other students. Researchers called for changes in BMI screening that prioritized privacy and an end to BMI reports sent home. They also emphasized the use of effective strategies that center on physical activity and eating healthy.

Read more at the Fit Study website or the JAMA Network website.