Caveat emptor. This is only my experience, but in my uncredentialed and completely unqualified opinion, it's probably applicable to most otherwise healthy people.
Before Thanksgiving 2010, I was listening this "The Skeptics Guide to the Universe" podcast, and mentioned among the stories was one called The Twinkie Diet about this nutritionist who held a premise that challenges most of the weight-loss industry's fad diets-du-jour: that you can lose weight on any diet, because it is calories that count. To drive home the point, he set for himself the challenge of losing significant weight on a diet consisting almost entirely of convenience store junk food. Two months and many cans of pop, packets of Doritos, and Twinkie wrappers later he'd done it, down 27 pounds.