A community-based weight control program designed by investigators now at St. Jude Children’s Research Hospital is the first such intervention to succeed for up to two years in reducing the prevalence of overweight children, according to a report presented at the American Heart Association meeting in Orlando, Florida.
The study, begun at the University of Memphis (Tennessee) and called Girls health Enrichment Multisite Studies (GEMS), 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). BMI is a measure of body fat based on a calculation using height and weight. Prevalence is a measure of how common a condition or disease is in a given population.
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 Robert Klesges, Ph.D., a member of the St. Jude Department of Epidemiology and Cancer Control and a professor of preventive medicine at the University of Tennessee Health Science Center. “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 health care professionals and represent a tool for disseminating this program nationwide.”
Klesges presented the results of the GEMS study at the annual American Heart Association conference this week as part of “The Best of Scientific Sessions 2007” program, which is broadcast to cardiovascular and stroke clinicians and investigators at more than 1,100 medical centers and institutions.
The GEMS study recruited 303 parent-daughter pairs at 10 community centers in Memphis, Tenn. The researchers randomly assigned 153 pairs into 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 about 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.
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 (e.g., 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 said.
“Increasing exercising might further reduce weight gain,” he said. “The long-term goal is to help girls avoid obesity in the first place and therefore avoid the health problems caused by obesity. One important thing we found is that we can increase the success rate if we don’t give up on these girls.”
Other authors of this study include Eva Obarzanek (National Heart, Lung, and Blood Institute), Lisa Klesges (St. Jude), Bettina Beech (Vanderbilt University, Tenn.), Shiriki Kumanyika (University of Pennsylvania), Barbara McClanahan (University of Memphis) and David Murray (The Ohio State University).
This work was supported by a grant from the National Heart, Lung, and Blood Institute of the National Institutes of Health and ALSAC.
St. Jude Children's Research Hospital
St. Jude Children's Research Hospital is internationally recognized for its pioneering work in finding cures and saving children with cancer and other catastrophic diseases. Founded by late entertainer Danny Thomas and based in Memphis, Tenn., St. Jude freely shares its discoveries with scientific and medical communities around the world. No family ever pays for treatments not covered by insurance, and families without insurance are never asked to pay. St. Jude is financially supported by ALSAC, its fundraising organization. For more information, please visit www.stjude.org.