The name "Flat Belly Diet" made me suspicious. But the program seems for real. I don't know if people will really be able to stick to a diet of 4 meals, 400 calories each, each meal including a "MUFA" food, plus 8 glasses of "Sassy Water" per day. But if someone can stay disciplined, I imagine that this plan could work.
By the way, here's the Flat Belly Diet website.