Ian K. Smith, M.D. is the #1 New York Times bestselling author of The Clean 20, SHRED, SUPER SHRED, The SHRED Power Cleanse, and Blast the Sugar Out.

He has created two national health initiatives - the 50 Million Pound Challenge and the Makeover Mile - and has served two terms on the President's Council on Fitness, Sports, and Nutrition. A graduate of Harvard, Columbia, and the University of Chicago's Pritzker School of Medicine, Smith is an avid fitness enthusiast and sportsman.

Jared C. Wilson is the director of content strategy at Midwestern Baptist Theological Seminary in Kansas City, Missouri, and managing editor of the seminary's website for gospel-centered resources, For the Church.

He is a popular author and conference speaker, and also blogs regularly at the Gospel Coalition. His books include Your Jesus Is Too Safe, Gospel Wakefulness, The Story of Everything, Unparalleled, and The Imperfect Disciple.