MARC SIEGEL, M.D., is a practicing internist, an associate professor at the New York University School of Medicine, and a Fellow in the Master Scholars Society at New York University. He is a columnist for the New York Daily News and Tribune Media Services, a member of USA Today's Board of Contributors, and a frequent contributor to the New York Times, Los Angeles Times, New York Post, Family Circle, and the Washington Post. Siegel has appeared regularly on the Today show, The Early Show on CBS, FOX News Channel, ABC News, CNN, and NPR.