Just go down the diet aisle of your local book store or library and you'll be overwhelmed with different diets all promising to give you the body you've always wanted. Some are truthful and say it will take a lot of work while some lie and claim that you don't have to work hard at all.
There are lots of outrageous statements made in these books and sifting through the truths and lies can be a challenge. The only way a diet can work is by reducing the amount of calories you intake to go under the amount of calories you burn.
There is not other way a diet can work. Special blood types,
drinking vinegar or other unusual diets will not work. There are diets such as low carb ones that will help you lose weight but aren't necessarily healthy.
If you are losing weight while on a diet, it means that you are burning more than you eat. It doesn't mean you are losing the weight in a healthy way. Use common sense. If the diet promises too much for the amount of work it requires, you might get disappointed at the results.