Yes, I have friends who lost a lot of weight on a diet. But they also told me that being on a diet is not the only reason why they were able to maintain their lean bodies. They were able to keep the weight off by also doing exercise every day, may it be running, walking, jogging, or just going to the gym. They all have different opinions in terms of the effects of diet, but they all agree on this:
The effect of diet is only short term. They said that as people begin to age, the body’s metabolism becomes slower thus, making it impossible to lose a lot of weight even if they stick with their diet. The majority of thes people, however, were able to keep their weight off by a diet coupled with exercise.