The 3-Week Diet is a revolutionary, rapid weight loss program that has been proven to melt away 23 pounds of stubborn body fat in just 21-days. The diet program was created by fitness guru, Brian Flatt of REV Fitness, a personal training studio in southern California.

The 3-Week Diet program began as an in-house 3-week program but due to the surge in popularity, the diet had been made into a "do-it-yourself" home-based system that achieves the same results.