David Zinczenko is the #1 New York Times bestselling author of Zero Belly Diet, Zero Belly Cookbook, Zero Belly Smoothies, and Zero Belly Breakfasts, and the co-author of the Eat This, Not That! franchise (which has sold more than eight million copies worldwide) and the Abs Diet book series. He is a health and wellness contributor at NBC News and has appeared on Today, Good Morning America, The Oprah Winfrey Show, and Rachael Ray and is the award-winning former editor in chief of Men's Health and editorial director of Women's Health, Prevention, and Best Life magazines. Zinczenko is also the founder and chief executive of Galvanized Media, where he oversees a number of life-changing wellness brands. He lives in New York City.

Stephen Perrine is also the author of The Men's Health Diet and The New American Diet. The former publisher of Rodale Books and editor in chief of Best Life, he has edited and published dozens of New York Times bestsellers and has appeared as an expert on health and nutrition on The Dr. Oz Show, Today, Good Morning America, and numerous other television shows. He lives with his family in New York City.