Tall and overweight children face increase risk of obesity in later years, says new study

American Journal of Preventive MedicineDec 1 2009

Being tall and overweight, or just being tall, might be a marker in children for an increased risk of being overweight or obese in later years.

These findings come from 2,800 children who participated in a larger study of cardiovascular risk factors. As third-graders and later as twelfth-graders, they were measured for height and weight, from which their body mass index (BMI) was calculated.

Seventy-nine percent of children who were overweight or obese in third grade were still overweight as high school seniors. However, overweight children who were in the top 25th percentile for height had an 85 percent probability of being overweight as seniors, compared with a 67 percent probability for overweight children who were shorter.

Even tall, normal-weight children had a higher risk, with a 25 percent chance of becoming overweight or obese as seniors compared with 17 percent for shorter, normal-weight children.

The study appears online and in the January issue of the American Journal of Preventive Medicine.

Parents and clinicians might tend to view tallness in children as protective against future obesity, said lead study author Steven Stovitz, M.D. "We may notice the extra weight but assume tall children will continue in their height-growth path," said Stovitz, an associate professor in the department of family medicine and community health at the University of Minnesota. In fact, he said, "Heavier kids tend to be taller."

"We should not just assume that a child of any height will grow out of excess weight," said Alice Ammerman, Dr.P.H., director of the Center for Health Promotion and Disease Prevention at the University of North Carolina at Chapel Hill. She noted that environmental or genetic factors associated with early weight gain may persist over time.

If both parents are tall, the child is likely to be tall due to genetics, Stovitz said. However, "if the parents are below average in height, then I think that parents and clinicians should consider that the increased height of the child who is also overweight may be due to early skeletal maturation, likely from excessive calorie intake."