(CNN) - A recent study finds that letting people know how many calories are in fast food doesn't mean they make healthier choices.
Researchers surveyed more than 15,000 customers of fast food restaurants in New York City before and after the city's enactment of calorie labeling regulation, requiring fast food chains to list calorie information on menus or menu boards.
In 2007, scientists spent several weeks monitoring what the lunch crowd was eating at 168 locations of 11 fast food companies.
They compared those choices to what people ordered two years later, after the new law went into effect.
Overall, people did not eat better or consume fewer calories when given this new health information, and only one in six people appeared to notice and make better food choices.
The customers who ate healthier consumed about 100 less calories per meal, but others actually took in more calories eating larger portion sizes that some restaurants had added during the two year period.
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