The Beverly Hills Diet Experience
My mom and I went on the Beverly Hills Diet when I was a teenager. I actually liked it, and it's the only diet plan that I have ever been on that I was actually able to lose the weight I needed to.
You could eat as much as you wanted for most things, and the things that were a specific amount you had to eat all of it.
The only real "rule" that there was to follow was that you had to wait certain time periods between changing from one group to another. That and you were supposed to weigh yourself every day at the same time.
The reason being was that this way you could get an idea of what foods you can eat and what you should stay away from. This is also why you would add "normal" foods back into your eating habits gradually.
The motto was "nothing is fattening if you plan for it."
Certain foods (fruits) were eaten to burn off certain foods. You would eat pineapple or papaya to burn off proteins, etc.
The entire diet was only six weeks long, then you would adjust as needed. It was the one and only time I have ever been able to get down to 135 lbs. I had started at 185 lbs.
I gained 10 lbs and went up to 145 and stayed at that weight for 5 years. The thing that made me gain the weight back was pregnancy, not fad dieting.
The one and only drawback that I saw to the diet was COST. It is very expensive to eat fresh exotic fruits everyday, as much as you want.