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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Bacteroides are microbes that dominate the guts of people who eat more animal protein and fat. National Institute of Environmental Health Sciences hide caption

itoggle caption National Institute of Environmental Health Sciences