In short, NO. I've tried some of the most popular fad diets, and what the experts say is true -- I gained back more weight than I lost and slowed my metabolism little by little after each attempt.
First, the Master Cleanse, a.k.a, the Lemonade Diet. This one promises that you'll shed weight quickly as a "byproduct" of this 10-day "cleanse." Who can resist that, right? The recipe calls for about a gallon of water, juice of 12 lemons, 12 ounces of Grade B maple syrup and cayenne pepper. You make this concoction daily for 10 days, and this is ALL you ingest. No food, no other drinks, just lemonade. It also includes a daily salt flush and laxative tea every night. A horrible experience and I'll spare you the details. Surprisingly, the lemonade part isn't bad -- it tastes ok, I had plenty of energy, and I really didn't need food. I did lose 10 pounds in 10 days. My husband lost close to 20. To come off the cleanse, you have a day of nothing but orange juice followed by a couple days of vegetable soup. Then guess what? The day I started back on solid foods, the weight came back with it. And since I didn't "eat" for 10 days, my metabolism was slower than before. This one may sound like a quick fix, but don't do it!
Slimfast is not much more than a shake full of nutrients and sugar that simply cuts your daily caloric intake drastically. Of course you'll lose weight, same as if you starved yourself. But the drawbacks to your metabolism are something to consider.
Perhaps the healthiest one I've tried is the South Beach diet. The first two weeks of this plan cut all carbs, relying on lean protein and vegetables. Then you slowly add back only whole grain carbs. The South Beach diet calls for a lifestyle change to lean protein and only whole grains. It has worked for millions of people who have the willpower to regularly pass on white bread, cookies, potatoes and pasta. I, however, do not.
In short, losing weight and staying healthy is mathematical -- if your calories in are more than your calories out, you will gain weight. If the calories you ingest are less than the calories you burn, you will lose weight. If you add 3500 calories, you will gain one pound. If you reduce your diet by 3500 calories, you will lose one pound. Simple as that. What I've found is that you can eat anything in moderation, as long as you keep track of it and don't go overboard. One bad day means being careful the next. I keep a food log and it helps me to track what I'm eating -- it also makes me rethink that 180 calorie cookie!