At NPR's Sound Bites Cafe, all food gets coded with one of three circles: Green is reserved for the most healthful dishes; yellow flags the "good choices;" and red signals the high-calorie foods to grab "on occasion." NPR hide caption

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A Safeway customer browses in the fruit and vegetable section at Safeway in Livermore, Calif. Justin Sullivan/Getty Images hide caption

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How a wealthy table set with a second course in the month of January would look, according to Mary Smith of Newcastle, in her 1772 book, The complete house-keeper and professed cook. British Library hide caption

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Dried beans and legumes are healthy and cheap. iStockphoto.com hide caption

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