No fast weight loss plans work. They usually cause increased, not reduced weight. If you permanently want to reduce your weight by five kilos, then you must be prepared to change your eating habits for the rest of your life.
The weight of the body is a direct result of your daily intake of food. No quick weight loss cure will have any effect except for a very short time, and will not change your weight permanently.
Before you decide to lose weight, you have to decide if the target is reasonable. A target weight which is less than what is normal for your body is difficult to achieve and can cause serious illnesses.