The first community-based weight control study to succeed for up to two years in reducing the prevalence of obesity in children was presented by researchers at St. Jude Children’s Research Hospital in November. The study, called GEMS, the Girls Health Enrichment Multi-site Studies, demonstrated a significant reduction in the prevalence of obesity among a group of 8-to-10-year-old African-American girls two years after the beginning of a program designed to reduce their body mass index (BMI).

The program’s success is important because obesity in children has risen from less than 5 percent in the 1960s to more than 15 percent today, according to the Centers for Disease Control and Prevention.

“Childhood obesity has tripled in the last 30 years,” reiterated Robert Klesges, PhD, a member of the St. Jude Department of Epidemiology and Cancer Control and professor of preventive medicine at the University of Tennessee Health Science Center. “Obesity is the second leading cause of cancer. I would argue it’s a catastrophic disease illness in children.”

The GEMS study recruited 303 parent-daughter pairs at 10 community centers in Memphis. The researchers randomly assigned 153 pairs to the active intervention group, which focused on weight-gain prevention; and 150 to the alternative group that emphasized self-esteem and social skills. A total of 41 percent of the girls were already overweight, and 25 percent came from households with an annual income of less than $20,000.

The GEMS program emphasized weight-gain prevention and weight loss during 14 weekly and 20 monthly meetings that were 90 minutes long. The objectives of these sessions included reducing participants’ intake of high-fat foods, increasing water intake, reducing intake of sweetened beverages, increasing fruit and vegetable intake, increasing frequency of moderate-to-vigorous physical activity and avoiding unhealthy behaviors.

“Children from low income families are at high risk for obesity because they have access to fewer health services,” Klesges said. “The educational materials developed for GEMS can be easily shared with other healthcare professionals and represent a tool for disseminating this program nationwide.”

Although girls in both the GEMS group and the comparison group gained weight since they were still growing, the prevalence of girls who remained overweight and obese throughout the study dropped by 40 percent in the GEMS intervention group by the end of the first year, compared to a drop of 21 percent among obese girls in the comparison group. By the end of the second year, the prevalence of obesity among the girls in the GEMS group was about 30 percent less than the prevalence at the start of the study, compared to a drop of 15 percent in the alternative intervention group.

This positive effect in the GEMS group occurred as a result of changes in dietary intake, particularly in the reduction of consumption of sweetened beverages such as soda. The GEMS girls did not appear to significantly increase their physical activity, which suggests that even without increased exercise, a proper diet can control weight gain in high-risk young girls, Klesges explained.

St. Jude plans to collaborate with other community partners dedicated to preventing childhood obesity in order to expand the program.

Until GEMS, there was no research to document how using prevention programs long term can prevent weight gain.



January 2008