Pilu Paka

Pilu paka is the subtle transformation of food at the atomic level that takes place through the cell membrane into the cytoplasm, outside the cell nucleus. After jathara agni and bhuta agni split food into its finer elemental components of Ether, Air, Fire, Water, and Earth, these elements circulate in ahara rasa through what is called the law of irrigation. Pilu agni, the fire residing in the cell membrane, then applies the law of selectivity by choosing which elemental molecules will enter the cell.

Digested molecules of food, water, and air enter the cell with the help of prana, while cellular waste is expelled with the help of apana. Pilu agni then transforms these elements from the asthayi (immature) form into the sthayi (mature) cellular components, nourishing the cytoplasm of every cell in the body.

The rishi Kanada, founder of Vaisheshika philosophy, described this process in detail. He discovered the atom, which he called anu, and pilu is another word for atom. His description of anu vaha srotas — the pathway of atoms — corresponds precisely to what modern science calls the cell, each with its own agni, ojas, tejas, and prana.

Pilu paka is the process of cellular digestion and nutrition that occurs at the cell membrane and in the cytoplasm outside the nucleus. It is the cellular counterpart of jathara agni's work in the gut.