Many might have noticed that becoming aged is a slow but steady process. But many might not have noticed that those who eat more and in large quantities become aged early.

The calorific intake of our body should be equal to the amount of work we do. If it is equal, then aging will be slow and not at a very early age. Research has shown that more secretion of thyroid hormone increases metabolism rate and with it increases the aging. So, one should reduce the amount of the hormone that gets secreted.
To reduce the amount of the hormone, consuming lesser amount of food is essential. From this itself we may note that a less eating slows down aging process. It can also be considered this way. More eating will make our cells to work more to digest them and to store the amount of energy. As a result of it, the workload on cells increases. So it initiates the wear in cell and with it degradation and aging. Also the intake energy is more and the metabolism is not balanced. So our body would increase the metabolism rate to cope with increasing amount of energy.
Increase in the amount of metabolism will result in increased secretion on thyroid hormone and as a result aging occurs. Several researches have been done on this and have shown the similar results. So as a conclusion from these researches, we can declare that eating less will reduce aging. But one should not eat very less as it may result in malnutrition. So one should have a balance between these two eat a small and nutritious diet to keep them young.