Miracle diets are typically starvation or low calorie diets. They cannot allow a person to lose fat regardless of advertisements to the contrary.2 A diet like the grapefruit or cabbage soup diet merely reduces your calorie intake. Sure, you might lose a few pounds however most of the weight loss on these plans comes from water, not fat.3
Fad diets are an unhealthy way to lose weight. Most fad diets are based on personal testimony, not scientific research though they may try to make you believe the contrary. These diets have not been approved nor regulated so you follow them at your own risk. Any diet on which you eat fewer calories than you need to get through the day is dangerous. Calories create fuel for your body without enough fuel your body will eventually run on empty. A person may experience symptoms of this with a headache, feeling of fatigue, dizziness, nausea, feeling faint or passing out. A person will only be able to lose weight with low calorie or starvation type diets because when the body is not fed it believes it is going through a period of true starvation and thus will hold onto its body fat tissue for future energy needs. In other words, the body does not understand that the dieter is simply trying to lose fat and does not know if and when it will be fed again. This holds true for grapefruit, celery and cabbage soup diets amongst others based on low calorie intake. When this happens a person will only be able to lose weight because instead of using carbohydrates and stored body fat tissue for energy as