I told him he would break his arm if he did that. But he did it anyway. iStockphoto.com hide caption

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Whether or not you'll someday get cancer or any disease can feel like a roll of hundreds of dice. Calculating the odds --€” and knowing what they mean --€” is tricky. Katie Harbath/Flickr hide caption

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Kids who can't resist temptation early on may have trouble with it throughout their lives. iStockphoto.com hide caption

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