Angelina Jolie took a genetic test to find out her risk of breast cancer, and had a preventive double mastectomy. Alastair Grant/PA Photos /Landov hide caption

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Bartender Matt Carucci told NPR in 2012 that he rarely feels safe biking in the city but often rides without a helmet anyway. "There are a lot of other ways to hurt yourself," he said. John Rose/NPR hide caption

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The U.S. ranks first in the world at stopping brain cancers, epidemiologists reported Monday. Here neurosurgeon Dr. Roger Hudgins and his assistant, Holly Zeller of Akron, Ohio, look at an MRI scan before performing surgery to remove a brain tumor. Mike Cardew/MCT /Landov hide caption

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A competitor stops for a cigarette after he broke down during the Enduropale race at Le Touquet Beach on February 22, 2009 in Le Touquet, France. Paul Gilham/Getty Images hide caption

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If you're overweight, the best way to spend your limited time exercising is aerobic activity, a researcher says. Rhodes ludovic/iStockphoto.com hide caption

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