He started out just like most people do when they start a diet, consuming fewer calories each day than he originally consumed before the diet. He worked hard in the gym and carried out this plan for a few months. Once she was happy with her weight, she started eating like she did before starting the diet and within a few weeks she gained all the weight back. The question is: why? Well, dieting may seem like the answer, but the truth is that dieting will lead to failure and cause a person's health to worsen. You can follow your diet plan perfectly, so how is it possible for someone to gain all their weight back and sometimes even more? One of the reasons it's difficult to keep weight off is because there is metabolic overcompensation for weight loss. If you reduce your body mass by 10%, you would expect your metabolic rate to decrease by 10%, but it actually slows down by more, by about 11-15% (Gretchen 2). To put it in simpler terms, dieting lowers your basic metabolic rate, meaning you can live on less food. Therefore, when you return to your normal food intake, which was already too high, you will gain weight even faster than before and will probably end up weighing more than you did before the diet. This explains why people who diet more often fail to lose weight