Oprah discovered Dr. Mehmet Oz, a telegenic young cardiothoracic surgeon at New York City's Columbia University, after she appeared as a guest on a Discovery Health Channel show he hosted in 2003. A best-selling author who moonlights as an Esquire magazine columnist, Oz was a success well before Oprah anointed him her health expert. But after five years and 55 episodes with the Queen of Talk — his tenure as a regular guest ended in May — it's safe to say she boosted his star. In September 2009 Oz launched his own syndicated program, The Dr. Oz Show.