For all the good aspirin can do in preventing second heart attacks and strokes, taking it daily can boost some risks, too — of ulcers, for example, and of bleeding in the brain or gut. 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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Aspirin helps reduce the risk of cardiovascular disease, but the jury's still out on cancer. iStockphoto.com hide caption

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