To turn some Americans away from fast food, it’s going to take more than posting calorie counts on the menus, according to a study published in the International Journal of Obesity and reported on NPR’s “Shots” health blog.

New York City passed a 2008 law requiring fast food eateries, and many other restaurants, to label and post the calorie content of their menu items. But before the law took affect, researchers polled 427 low-income, mostly minority parents and adolescents who regularly eat fast food about their eating habits. After the laws were enacted, researchers interviewed more people of similar ethnicity and economic status before they entered fast food eateries—and checked their receipts when they left.

Additionally, scientists also surveyed a comparable control group of people who dined at fast food restaurants in Newark, New Jersey, where there aren’t any calorie labeling laws.

Many of the study participants were adolescents who purchased their own food. Of those teens, about half said they saw the calorie counts and 9 percent said the information influenced their dining choices.

What researchers didn’t find was a significant difference in calorie intake before and after the labeling law took effect. In addition, scientists saw similar results when parents bought food for their kids.

Wondering why the calorie labeling laws seemed ineffective? Well, the closeness of the restaurants to the neighborhood, lack of healthier meal choices in the area, food price, peer pressure and advertising could be influencing teens’ choices, said Brian Elbel, PhD, MPH, an assistant professor of medical and health policy at New York University, and the study’s lead researcher.

While this was only a small, targeted study, Elbel said, it showed that more public policy work is needed to help educate people about calorie counts and what they mean for better health.

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