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Does calorie information help consumers make healthier choices Not always. But a new study finds that when calorie counts are presented in an easily understandable way, even teenagers--those experts in never listening to useful advice-can be persuaded to avoid high-sugar choices.
For the new study, researchers from the Johns Hopkins Bloomberg School of Public Health went to corner stores in predominantly black neighborhoods of Baltimore and posted signs showing calorie information about sugary drinks on refrigerated beverage cases.
The researchers tested three different signs, each brightly colored, in four corner stores. They collected data for 1,600 beverage purchases by black teens including 400 sales during a no-sign baseline period.
Overall,they found, teens were 40% less likely to buy a sugary drink after seeing any of the posted calorie counts than when they were given no information. They were even less inclined to buy a soda or a fruit drink after viewing the sign that presented the exercise equivalent.
Previous studies on calorie counts and buying behavior have been conflicting. A NYU School of Medicine study demonstrated that caloric labeling did not change the number of calories teenagers and parents purchased at fast food chains in the city, with teens buying a whopping (巨大的)725 calories on average even after the labeling.
The failures may have to do with how the information was presented. Calorie information works best when it is displayed clearly and visibly alongside the items and prices listed on menus. But even then,it may not matter if consumers don’t know how to interpret it,for instance, how many calories they’re supposed to eat in a day.
"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,"lead researcher Sara Bleich at the Johns Hopkins Bloomberg School of Public Health said.
With American teenagers consuming an average 300 calories per day from sugary drinks alone--a significant contributing factor to children’s overweight and obesity rates--adding calorie-information posters could help.

What was the finding of the researchers from the Johns Hopkins Bloomberg School of Public Health（）

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