December 19, 2011

Teens pick water when sugary beverage calorie count is more understandable

Thirsty? If you’re a teen, you may be more inclined to reach for plain old H2O if you knew how many calories were in sugar-sweetened beverages—this according to a new study led by researchers at the Johns Hopkins Bloomberg School of Public Health.

The researchers examined the effect of providing clear and visible caloric information about sugar-sweetened beverages such as soda, sport drinks, energy drinks and fruit juice at neighborhood stores, and found that providing easily understandable caloric information, specifically in the form of a physical-activity equivalent, may reduce the likelihood of sugar-sweetened beverage purchases among adolescents by as much as half. The results are featured in a recent issue of the American Journal of Public Health.

Consumption of sugar-sweetened beverages has been associated with obesity and is highest among minority and lower-income adolescents. The study was conducted at four corner stores located in low-income, predominantly black neighborhoods in Baltimore.

“People generally underestimate the number of calories in the foods and beverages they consume,” said Sara Bleich, an assistant professor in the Bloomberg School’s Department of Health Policy and Management. “Providing easily understandable caloric information—particularly in the form of a physical-activity equivalent, such as running—may reduce calorie intake from sugar-sweetened beverages and increase water consumption among low-income black adolescents.”

For the intervention, one of three signs was randomly posted with the following caloric information: “Did you know that a bottle of soda or fruit juice has about 250 calories?” (absolute caloric count), “Did you know that a bottle of soda or fruit juice has about 10 percent of your daily calories?” (percentage of total recommended daily intake) or “Did you know that working off a bottle of soda or fruit juice takes about 50 minutes of running?” (physical activity equivalent). The researchers collected data for 1,600 beverage sales—400 during a baseline period and 400 for each of the three caloric-condition interventions—sold to black adolescents, ages 12 to 18. They found that providing any caloric information significantly reduced the odds of sugar-sweetened beverage purchases by 40 percent relative to the baseline of no information. Of the three caloric-condition interventions, the physical activity equivalent was most effective, reducing the odds of black adolescents’ purchasing a sugar-sweetened beverage by 50 percent.

According to the Centers for Disease Control and Prevention, more than one-third of adults and 17 percent of children in the United States are obese. Obesity increases the risk of many adverse health conditions including type 2 diabetes, coronary heart disease, stroke and high blood pressure.

“Because of the inclusion of mandatory calorie labeling in the recent health reform bill, it is critical to explore the most-effective strategies for presenting caloric information to consumers on fast food restaurant menu boards,” suggest the study’s authors.

The study was written by Bleich, Bradley J. Herring, Desmond D. Flagg and Tiffany L. Gary-Webb.

The research was supported by grants from the Robert Wood Johnson Foundation and the National Heart, Lung and Blood Institute.