Though some people might need more of specific vitamins, multivitamins don't help most people, studies say. iStockphoto hide caption

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If only it was as simple as popping a supplement and being set for life. But alas, no. iStockphoto.com hide caption

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Ads often tout dietary supplements and vitamins as "natural" remedies. But studies show megadoses of some vitamins can actually boost the risk of heart disease and cancer, warns Dr. Paul Offit. iStockphoto.com hide caption

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In Washington's Columbia Heights neighborhood, Claire Robertson, a grad student, talks with Scott Hensley about retail health clinics. David Schultz/NPR hide caption

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