We cannot have only one definition of a fad diet, and we have to make a difference between some good and some very bad and dangerous fad diets. Many refer to this diet as the ones that don't actually work, but fad simply means something that is popular, and something that quickly falls out of favor. Some call these diets fad because they are either dangerous or not effective. But it is not fair to enlist all diets as fad diets. So here we will be talking about the side effects of a bad and dangerous fad diet.
The dangerous sides of all of these fad diets are that they restrict you to eating just one kind of food. This is completely wrong. Even eating only veggies and fruit is not healthy. Your body needs natural fat, proteins, carbs and vitamins. Your metabolism cannot work without them. But the good thing is that it makes you get rid of all that junk food and soda. These are the things that your body never will have any good need from.
The other misconception that these diets promise is that you can lose in a very short period of time. This is impossible since it took you a long time to get all that and it will take you a lot more time to lose it. These diets claim things like you can lose 10 pounds in one day, which is completely unrealistic. Some people get tricked into believing because they do lose pounds during the first week. But there is one thing that must be clears. You are not losing fat, more likely that you have lost some additional water, toxins but not any body fat. No matter how much you hate exercise, they are the only ones to help you burn all that excessive body fat while helping you speed up your metabolism.
Third negative side to these fad diets is the yo-yo effect. People that finish with this diet tend to gain all their back after just a short period of time. This happens because your body is in constant need for all those necessary items to keep your metabolism running. After you are done with fasting, you start eating more then before to indulge in all that hunger and all that food you were craving for. While listing some dangers of fad diets, I should mention that diets that allow you to indulge every once in a while in your cravings, and have a balanced meal, are good diets.
At the end fad diets are bad because they offer results that they cannot back up. All the results achieved will have grave negative effects on your health. Moreover, all are just some short-term loss plans, not something to consider in the long run. So that ends the list of dangers in fad diets.