If you want to get into shape, make sure you're keeping a good balanced diet. You want to make sure your body is getting all the right nutrients and enough calories so that it can exercise and build muscle properly. If you're not getting enough calories, you won't have the energy you need to exercise.
Fad diets may seem like the best way to lose weight fast. Of course, if fad diets were actually effective, they would cease to become fads and become mainstream. A fad diet that focuses on a certain set of foods may sound interesting at first, but the novelty soon wears off. Fad diets teach you nothing when it comes to nutrition. Instead, try to choose a diet that will help you learn how to eat healthier foods.