In the south of India, meals were traditionally eaten on banana leaves, while sitting cross-legged on the floor. Even today, this is how meals are served at weddings and other celebrations.
It is believed that this practice has several benefits. Ayurveda gives a great deal of importance to banana leaves, and uses it in many of their treatments. When hot rice is placed on the leaf, it absorbs the chlorophyll from the leaf. Sitting cross-legged on the floor while eating helps in digestion, and ensures that one doesn't eat too much.
Here is an extract from .com/culturebuy
Our hands and feet are said to be the conduits of the five elements. The Ayurvedic texts teach that each finger is an extension of one of the five elements. The thumb is agni (fire) -- you might have seen children sucking their thumb, this is nature's way of aiding the digestion at an age when they are unable to chew; the forefinger is vayu (air), the middle finger is akash (ether -- the tiny intercellular spaces in the human body), the ring finger is prithvi (earth) and the little finger is jal (water).