There is no need for you to take the vitamins, as vegetables, fruits and nuts contain adequate natural vitamins. Additional synthetic vitamins have not proved to be of any potential in the world literature. As far as nap after lunch is concerned, the scientific reasoning is very simple. After having lunch or dinner, one should not be involved in a strenuous physical or mental activity as there is more pooling of blood circulation towards the stomach to digest the food and there is relatively lesser circulation in the brain and heart. That is why one feels sleepy after meals. When the circulation in the heart is already compromised, napping has tremendous potential in maintaining the vital health of the brain and heart together.