January 22, 2007

Excess Pounds on Pre-Teen Girls Pose Future Health Risks

Two young African American girls smiling at each other

Girls in their “tween” years—the ages of 9-12—are particularly vulnerable to excess weight gain and related health risks that may continue into adulthood, according to a recent study. Researchers suggest that interventions targeted to this susceptible age group may help prevent weight-related problems in the years to come.

Childhood obesity is a growing concern in the U.S. Since 1980, the percentage of overweight youth and adolescents, ages 6-19, has more than tripled. Several studies are under way to better understand how and when childhood weight gain arises.

The latest findings come from the NIH's National Heart, Lung, and Blood Institute Growth and Health Study, launched in 1985. This multi-center study enrolled more than 2,300 girls, 9- to 10-years old, and followed them for more than a decade. Slightly over half of the girls were African American, the rest Caucasian.

The girls received 10 annual health evaluations, with clinicians measuring height, weight, blood pressure and cholesterol levels.The girls were considered overweight if they were in the 95th percentile on standardized growth charts. Later, as young adults (21-23 years old), the participants reported their own weight to the researchers. Young adult obesity was defined as a body mass index (a ratio of weight to height) of at least 30.

In the January 2007 Journal of Pediatrics, Dr. Douglas R. Thompson of the Maryland Medical Research Institute in Baltimore and his colleagues reported that girls 9-12 years of age were especially vulnerable to weight gain and related risk factors. The girls were far more likely to become overweight at 9-12 years than in later adolescence. Excess weight brought cardiovascular risk factors, like increased blood pressure and cholesterol levels, even in some 9-year-old girls.

The scientists also found that weight problems were likely to persist. Compared to their non-overweight counterparts, girls who were overweight during childhood were 11-30 times more likely to be obese as young adults. In addition, there were differences between African American and Caucasian girls, with black girls 1.5 times more likely to become overweight at any given age than white girls.

This study highlights the importance of helping girls as young as nine maintain a healthy weight. Because African American girls were at greater risk for weight gain, which can lead to other health problems, the results also suggest that obesity prevention efforts need to take into account cultural differences.

Related Links