BALTIMORE -- Teenagers from lower-income, predominately black neighborhoods in Baltimore purchased fewer sodas, energy drinks and other sugar-sweetened beverages after seeing calorie information on signs posted in convenience stores, according to a study published last week in the American Journal of Public Health.
The study, which was supported by the Robert Wood Johnson Foundation through its Healthy Eating Research program, evaluated three different ways of providing adolescents with calorie information. One poster noted that a typical bottle of soda or fruit drink contains 250 calories. Another sign told customers that a bottle of soda or fruit drink contains 10% of their daily recommended calories. The third sign informed teens that they would have to jog for 50 minutes to burn off the calories in a single bottle of soda or fruit drink.
To translate calories into a physical activity equivalent, researchers calculated that a 15-year-old who weighs 110 pounds would need to replace sitting with running for 50 minutes to burn off the 250 calories in a bottle of soda.
Researchers discovered that providing any calorie information reduced the odds that teenagers would purchase a sugary drink by approximately 40% compared with providing no information. Calorie information provided as a physical activity equivalent was most effective, reducing the odds of the Black adolescents purchasing a sugar-sweetened beverage by 50%. This is the first study to examine whether different presentations of calorie information for sugar-sweetened beverages might influence customers' purchases.
"Teenagers were less likely to purchase a sugar-sweetened beverage and more likely to select a healthier choice like water after they saw the calorie information signs," said lead researcher Sara Bleich, PhD, assistant professor at the Johns Hopkins Bloomberg School of Public Health. The study noted that nonsugar-sweetened beverages, such as water or diet soda, accounted for 6.7% of all purchases at the beginning of the study. After calorie posting, those purchases roughly doubled, rising to 12% to 14%--depending on the sign used to present caloric information.
"This study showed that black teenagers will use calorie information, especially when presented in an easy- to-understand format, such as a physical activity equivalent, to make healthier choices when it comes to buying a drink at the local corner store," said Bleich. "Most consumers underestimate the number of calories in a can of soda, and they often do not realize that such calories can add up quickly."
Bleich and her colleagues focused on four corner stores within walking distance of middle and high schools in lower-income, mostly black neighborhoods in Baltimore city. The team randomly posted the three types of caloric information on brightly colored signs on beverage cases and then kept track of beverage sales at each corner store.
Previous research shows that the average American teenager consumes roughly 300 calories per day from sugar-sweetened beverages.
In response to "Reduction in Purchases of Sugar-Sweetened Beverages Among Low-Income Black Adolescents After Exposure to Caloric Information," the American Beverage Association issued the following statement: "With our 'Clear on Calories' initiative, the beverage industry is already providing calorie information at the fingertips of consumers. We agree that consumers should be armed with information about the calories contained in the foods and beverages they choose. By placing new calorie labels on the front of every bottle, can and pack we produce, we're helping consumers--especially parents--choose the beverage that is best for them and their families. This is an effort that supports First Lady Michelle Obama's 'Let's Move!' campaign."