In this photo taken April 3, 2013, nutrition scholar Prof. Barry Popkin, head of the University of North Carolina Food Research Program, discusses his study, what foods Americans are purchasing in ... more 
In this photo taken April 3, 2013, nutrition scholar Prof. Barry Popkin, head of the University of North Carolina Food Research Program, discusses his study, what foods Americans are purchasing in stores and eating, in his office at UNC-Chapel Hill. Popkin is leading a massive project of researchers who are creating a gargantuan map, something he calls "mapping the food genome." "We're interested in improving the public's health and it really takes this kind of knowledge," he says. (AP Photo/Gerry Broome) less 
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Associated Press | Photo By Gerry Broome
Sun, May 19, 2013 1:44 PM EDT