BMI Calculator Especially for Kids

By Alfredo Flores
January 28, 2004

Agricultural Research Service scientists at the Children's Nutrition Research Center (CNRC) in Houston, Texas, have developed an interactive computer tool to help parents keep their growing children's weight on track.

Based on a revised growth chart from the U.S. Centers for Disease Control and Prevention (CDC), the Children's BMI (Body Mass Index) and Percentile Graph Calculator provides a number that corresponds with a child's weight and height for age.

The BMI is a relationship between weight and height that is associated with body fat and health risk. The CDC has provided BMI ranges for those at risk of being overweight. A BMI of more than 25 is considered overweight.

The new computer tool also plots the child's BMI percentile on a chart that is age-appropriate, giving parents an important aid for determining the proper weight for their child.

Traditionally, the BMI has been used as a measure of body fat based on height and weight that has been applied to adult men and women. Unlike adults, the average BMI of children changes as they grow. Therefore, a BMI percentile value has more meaning than just the BMI value.

Roman Shypailo, an instructor of pediatrics at the Houston-based Baylor College of Medicine and a CNRC body composition expert, is the project's principal architect. Parents should watch out for significant "drifting" in their child's readings, either up or down, when using the BMI percentile calculator over time, according to Shypailo.

Monitoring a child's BMI percentile could help parents catch potentially unhealthy changes in the child's weight at an early age, so they could more easily make changes in the child's diet and exercise to correct the problem sooner.

The CNRC is operated by the Baylor College of Medicine in cooperation with Texas Children's Hospital and ARS, the U.S. Department of Agriculture's chief scientific research agency.