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President Barack Obama will turn 50 on August 4, 2011. Is his job cutting his life shorter?

Thursday, President Obama turns 50. He'll start celebrating Wednesday at a DNC fundraiser in his home town of Chicago, where musical acts like OK Go and Herbie Hancock will play. But are the stresses of the presidency taking years off his life? Professor Howard Friedman of UC Riverside co-authored a book called "The Longevity Project" which explores the factors leading to a long life. He shared some tips for the president, and others who are getting older.