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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Aspirin has been prescribed for decades as a simple way to reduce heart disease risk, but doctors still aren't sure how it works. iStockphoto.com hide caption

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Insomnia, feeling isolated, and bursts of anger are symptoms of the anxiety disorder known as PTSD. iStockphoto.com hide caption

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The danger of death by heart attack or suicide is greatest in the first week after a cancer diagnosis. Max Delson Martins Santos/iStockphoto.com hide caption

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