Would you think twice about that 20-ounce soda if you were informed that it would take 5 miles of walking — or 50 minutes of running — to burn it off? Justin Sullivan/Getty Images hide caption

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A sign displaying calorie counts is seen in a Subway restaurant in New York City in 2008. A yet-to-be-finalized federal rule requiring big chain restaurants to post calorie counts has likely led eateries to tweak their menus. Mario Tama/Getty Images hide caption

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One of Huddle House's signature dishes is the Philly Cheese Steak Tots: steak covered with cheddar cheese sauce and shredded cheese, on an open-faced omelet with Tater Tots. Huddle House hide caption

itoggle caption Huddle House

Teen boys are far less likely than girls to check out calorie counts before biting into that burger, researchers say. iStockphoto.com hide caption

itoggle caption iStockphoto.com