One recent study found that people were able to burn up an extra 450 calories a day with one hour of moderate exercise. That can include walking briskly, biking or swimming. hide caption

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Brain researchers say the big fluctuations in IQ performance they found in teens were not random — or a fluke. hide caption

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Even with a strong maternal relationship, teenage boys who watch a lot of TV acquire their attitudes toward sex from gender stereotypes seen on the tube, a new study says.

Andrea K. Gingerich/ hide caption

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Victims of the plague are consigned to a communal burial during the Plague of London in 1665.

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