Some people do not have difficulties in staying trim, bust for most of us regardless our age it is not easy to manage weight and always stint yourself in food. The reason is that getting used to small portions requires a lot of stamina, effort and time, especially if you are not often at home. It might lead to cravings and ultimately induces caving.
The great message is that there are foods that do not contain much energy per gram, but at the same time are rich in nutrients, fiber, and water. We can eat them without fearing that we gain weight; it will be actually the other way round.