Many children in public schools have their height and weight measured annually. This information is then used to calculate their body mass index (BMI). BMI is a screening tool used to determine whether a child is overweight or underweight. A child’s BMI is based on the ratio of height to weight. BMI is reported as a percentile ranking based on the child’s age and gender. The Centers for Disease Control (CDC) created the percentile ranges to identify children who may be at risk for serious health conditions such as insulin resistance (a precursor to diabetes) and heart disease.
Like all screening tools, BMI can produce some false positives or negatives. For example, a student may have an artificially high BMI due to a high level of lean body tissue or muscle, as may be found in a well-conditioned athlete. Checking a child’s growth over time is more important than a one time measurement. If A child’s weight is not in the healthy weight category, it is recommended that they visit a healthcare provider to discuss the results.