Some men take testosterone hoping to boost energy and libido, or to build strength. But at what risk? iStockphoto hide caption

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There's more than one reason to aim for a good night's sleep. Charles Taylor/iStockphoto.com hide caption

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The active ingredient in Propecia, a baldness remedy approved by the Food and Drug Administration in 1997, is showing new promise as a way to prevent some prostate cancers. AP hide caption

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A billboard advertising robotic surgery hangs outside Boston's Fenway Park in 2009. Hospitals and doctors have heavily promoted robotic surgery. Charles Krupa/AP hide caption

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Prescriptions for testosterone medications, such as Testim and AndroGel, to men 40 and older rose threefold over the decade ending in 2011 MICHAEL BRYANT/MCT/Landov hide caption

itoggle caption MICHAEL BRYANT/MCT/Landov

A man smokes a cigarette as he takes a break at a fruit market in Hyderabad, India. Smoking tobacco is eight times more prevalent among Indian men than women. Noah Seelam/AFP/Getty Images hide caption

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If you're interested in buying Viagra, Pfizer, the drug's maker, will now sell it to you from its official website. William Vazquez/AP hide caption

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Terry Dyroff, of Silver Spring, Md., had a PSA blood test that led to a prostate biopsy. The biopsy found no cancer but did give him a life-threatening infection. Jose Luis Magana/AP hide caption

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A rabbi holds up a pillow used during ritual circumcision at a synagogue in Berlin. Markus Schreiber/AP hide caption

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