Ian K. Smith is an author, physician, and television personality best known for his New York Times bestsellers such as Shred: The Revolutionary Diet, The 4 Day Diet, and Extreme Fat Smash Diet. He is the host of the nationally syndicated radio show HealthWatch and the Emmy-nominated television show The Dr. Ian Smith Show. He is also the medical contributor for NBC's Today Show and the founder of the 50 Million Pound Challenge.