BOB HARPER is a world-renowned fitness trainer and the longest-reigning star of the NBC reality series The Biggest Loser, which finished its sixteenth season in 2015. He has released several popular fitness DVDs and is the author of the number one New York Times bestselling books The Skinny Rules, Jumpstart to Skinny, and Skinny Meals. Harper lives in Los Angeles with his dog, Karl.
GREG CRITSER is a longtime science and medical journalist. The author of the international bestseller Fat Land: How Americans Became the Fattest People in the World, he lives in Pasadena, California.