Does a child's height affect their future risk of obesity?

Children who are relatively tall for their age have a higher risk of developing obesity, according to a new study published in Obesity.

In the study, investigators examined the health records of 2.8 million children who were initially examined between 2 and 13 years of age. When they were re-examined an average of 4 years later (but up to 13 years later), taller children were more likely to have a higher body mass index than shorter children.

For example, among the thinnest children at the start, the prevalence of obesity at the second exam was 5-fold higher in the tallest children than in the shortest children (3.1% versus 0.6%). Among the heaviest children at the start, the respective prevalence rates of obesity were 89.5% versus 53.4%.

The association between taller height and obesity at the second exam was strongest in children who were initially examined when they were younger than 7 years old.

"As about half of this association is independent of the initial body mass index of the child, the use of height may be a simple way to more accurately classify which children will become obese," said lead author David S. Freedman, Ph.D., of the Centers for Disease Control and Prevention.