Most diets don’t work. While you may initially lose weight on a diet, that weight will probably return once the diet ends. Also, the more extreme the diet is (e.g., Grapefruit Diet), the more likely you are to not only gain back the lost weight, but to gain a few additional pounds too.
A diet that requires you to fast will slow down your body’s metabolism. When this happens, you burn calories more slowly because your body enters into a starvation mode. When you finally break your fast and eat, your body extracts all the energy that it can out of your food, resulting in weight gain. Whatever amount of weight was lost during your diet comes back almost immediately.
Alternately, a diet that requires you to eat only one type of food is also bound to fail. While eating one type of food initially causes weight loss (primarily by limiting your food intake), it is inevitable that boredom will eventually set in. Likewise, the diet may result in a vitamin or mineral deficiency. Once such a diet ends, you may start overeating the foods that were restricted by your diet plan. This can easily lead to weight gain.
Ideally, diets should be long-term programs that focus on gradual weight reduction. They should encourage changes in eating habits that are life-long rather than temporary. In this way, you avoid the yo-yo effect of most diet plans and actually maintain your weight loss long-term.
1