First of all,it goes down to the tradition of blending with nature.All those things that are associated or that which lives off Nature is part and parcel of our heritage. A few among those are
Worshipping the cow-using cow dung to clean because it has cleansing properties and because the cow is revered as Gomatha and is a repository of goodness and nourishment because it it the next to one's own mother.
The second is using a plantain leaf.
It is a sign of auspiciousness. When a person buys bundles of plantian leaves,we can know that there is a celebration in his house.
That is why it is called 'Thala vazhai illai' where a lot of traditional foods are served.
Whatever customs our ancients followed had some reason. The plantain leaf has a lot of essential vitamins and minerals. But it would be asking for too much if we decide to eat a plantain leaf because it is good for health.
So we eat from it and not eat it.
When you serve very hot rice on the leaf, you can notice how the color of the leaf under the rice changes.
It turns to a brownish green color. It means that the hot rice has absorbed the essence of the leaf. And when we eat this rice,the nutrients from the leaf gets into our system.
The culimation of a meal on a plantain leaf is chewing the betel leaf,which is again full of nutrients. The betel leaf has vitamins A and C and accompanied by chunam or limestone which has vitamin C,the paan aids in digestion.