Cityfile: New York's Most Notable and Influential

One doesn't think of New Yorkers as particularly gullible or naive, but when it comes to food, we're totally clueless and assume that anything labeled low-fat is automatically low-calorie—at least according to marketing guru Pierre Chandon, who's turned his attention to discovering why Americans, despite being so rich and well-informed, are still such fatties. The Times took his questionnaires out into the field and discovered that "health halos"—ideas about which foods are virtuous based on health campaigns and restaurant advertising—meant that even the know-it-alls in Park Slope embarrassed themselves when it came to guessing calorie content.More