Body Mass Index Reporting at School: Helpful or Harmful?

Childhood obesity is currently recognized as one of America’s most serious health problems, with serious repercussions for disease and disability later in life. As a result, some authorities have recommended identifying children at risk through school-based measurement and reporting of body mass index (BMI, kg/m²). In 2003, Arkansas became the first state to require annual BMI screening in their public schools. Similar legislation is now in place in 20 states.

Maria G. Portilla, MD, writing in the Journal of the American Dietetic Association (2011; 3:442) notes that although organizations such as the American Academy of Pediatrics (AAP) have recommended annual BMI measurements, these measurements were never meant to be done in schools, but by primary care physicians as part of regular annual exams. In 2009, the AAP raised the possibility that BMI screening programs might worsen stigma about weight and body image problems already experienced by obese children and teens, leading to inappropriate weight loss practices that could result in an eating disorder (Pediatrics 2009; 124[suppl]:S89).

Two cases

Dr. Portilla reported two cases of students treated at a tertiary children’s hospital who reported disordered eating and excessive exercise after getting the results of their BMI screening at school. One student was a 14-year-old male whose BMI screening was done in spring 2006. After he was teased by other students and became concerned about his elevated BMI (31.4), the boy began dieting, purging, and exercising excessively to lose weight over the summer. He lost 41.8 lb over the summer, and presented at an eating disorders clinic that fall. He had dizziness upon standing, chest pain on exertion, cold intolerance, and lethargy. He was admitted to the hospital for medical stabilization and refeeding, and after 20 days was discharged and followed up with therapy and medical/nutritional management in the eating disorder clinic for 6 months. There was no follow-up by the school system regarding the BMI report because state law does not mandate this. The boy’s disordered eating resolved and he was referred to his family doctor for follow-up.

A second student, a 13-year old female, began dieting and exercising excessively after learning about her “elevated” BMI (20.8) on a report card in spring 2004. She avoided “junk foods” and greatly increased her exercise; her mother attributed these new behaviors to her daughter’s concerns about her BMI. After treatment by a counselor and nutritionist for 6 to 8 months, the girl had some improvement, but then began to restrict her diet when school began in the fall. The girl had body image distortion but denied any bulimic behavior. She was depressed and had thoughts of harming herself. She presented at the eating disorder clinic the next year, with weakness, dizziness, fatigue and syncope. The “only” physical finding was malnutrition; a mental health professional diagnosed her as having an eating disorder not otherwise specified and depression with suicidal ideation and recommended that the girl be admitted for treatment. The parents refused. The girl was followed-up in the eating disorders clinic, where she had regular therapy and medical/nutritional monitoring. She gradually improved, gaining weight to a normal range; she had her first menstrual period 14 months after starting therapy. She was discharged from the program nearly 2 years after her initial presentation and was referred back to her primary care physician.

Short-term effects of the Arkansas program

Dr. Portilla points out that among students who received BMI assessments in Arkansas during 2007, 72% reported an increase in physical activity, 11% indicated they were embarrassed by their BMI measurements, 27% started dieting after learning their BMIs, and 5% began taking diet pills (MMWR Morbid Mortal 2008;122e682). And, as a result of the school health report cards, 19% of parents reported they had considered putting their children on diets, even though the reports suggested that a pediatrician should evaluate the child first. The Youth Risk Behavior Survey data noted that in 2007, Arkansas students, when compared with students at a national level, were more likely to practice unhealthy eating behaviors, such as taking diet pills, vomiting, or taking laxatives to control their weight. Some states are now re-thinking the value and impact of BMI screening at school, and some legislators have introduced legislation to overturn BMI screening by schools.

The author agrees that childhood overweight and obesity are paramount health problems in the U.S. School and state governments are attempting to inform parents about this problem, but she suggests that if schools are to include such programs, a better tactic should be to include specific steps to encourage healthy lifestyles and efforts to avoid potential harm. Other suggestions are to include a registered dietitian in the school’s process of obtaining BMI assessments and notifying parents, as well as providing a healthy eating environment at school, says Dr. Portilla.